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Tag: the Brontë Society
Coming Home To Haworth: Charlotte Brontë's 'little book'.
Screenshot of the crowdfunding campaign to buy Charlotte's book
Last Monday, November 18th, a little book came up for auction in Paris; a VERY little book, one and a half by two and a half inches. The author was Charlotte Brontë, aged 14, and the tiny volume is one of six miniatures written in the Yorkshire parsonage where the Brontë children grew up. A campaign was launched by The Brontë Society to buy it, and a huge wellspring of public goodwill enabled the organisers to reach, and go beyond, the crowdfunding target of £80,000 showing just how much value we still place on the world of books and literature, and how the amazing Brontë story resonates not only for locals but also for readers all over the world.
Haworth Station
'Go, litel book!' Go back to Haworth and do homage to thy mistress. According to the latest news it is still in Paris, but has its passport (!) and will head off shortly, hopefully going on display in February 2020 after renovations at the Museum are completed. 2020 will also celebrate the bicentenary of Anne.
You can find out more about the Brontës and even join the society (one of the oldest literary societies in the world) here. There are also numerous videos on YouTube about them (one I particularly like is listed in the links at the end of the blog). But as part of my own personal homage to those sisters, in 2017 I wrote a novella, The Passage of Desire, set in Haworth in the early 1990s. It's FREE to download this weekend, Saturday 23rd and Sunday 24th November, here and here. (Kind) reviewers have commented:
'I loved the rich descriptions of the Yorkshire countryside and how the passion evoked in Wuthering Heights is intertwined with the story.
…the Brontë landscape is beautifully described; clearly the writer knows it very well. There are some pleasing literary references which Brontë fans will enjoy…..
…the Brontës float in and out of the story, both literally and metaphorically, and the tale is something of a homage to romanticism.'
I hope those floating Brontë spirits, wherever they may be, are celebrating this weekend. Youpee!
The moors "long swells of amethyst-tinted hills…"
Read on for an extract from The Passage of Desire, in which 7-year-old Caroline, one of the narrators, visits the parsonage museum for the first time with her mother, Alexandra, and their hosts, Juliet and Oliver, and is struck by the miniature booklets.
Chapter 13 The Brontë Museum
The churchyard, Haworth
"Caroline had been pestering for a visit to the museum. And so, one bright morning, they found themselves in the shade of the village churchyard on their way to the parsonage. The tower of St Michael and All Angels was just visible as they stepped into a forest of graves, wedged into every available inch of space, the headstones standing shoulder to shoulder like chessmen, some with pointed tops, some shaped like mitres, others representing stars or fleur-de-lys, or crowned with ornate pediments. Some were upright, others listed to the side. Moss and lichen had blurred the blackened inscriptions but it was possible to make out the words if you looked closely. Thousands of bodies, it was said as many as forty thousand, lay together in this confined space, a reminder that the now pretty village of Haworth had once been a grim and insalubrious place, home to workers in the textile mills that spread across the valley, fed by the plentiful water pouring down from the rain-soaked moors. Tuberculosis and other diseases stalked the village streets, carrying off the weak. Sometimes, stopping to look, you would see the names of entire families marked on the headstones. Juliet always got the shivers when she passed through.
Caroline danced from one grave to another squatting down to decipher the words.
'Here lies Martha, be…love…beloved daughter of James and Eliza…died in the ten, the tenth, year of her age…Luke, in the 2nd year of his age, Mary, in the 6th year of her age.'
She stopped short and slid her hand into Alexandra's.
'Why did all these children die, Mummy?'
Alexandra too was feeling uncomfortable. This was not a peaceful resting place, like some she had visited. In spite of the fine day it was dark and chilly under the tall trees where rooks cawed. The graveyard was full of rustlings as the wind passed through the high branches and shook the stands of yew and ibex. White dandelion clocks floated in the unkempt grass.
'Remember what Daddy told you? In those days, that was Victorian England, the people who lived here were very poor, they didn't have warm houses and good food. They worked long hours in the mills. Remember when Juliet told you about Wuthering Heights? How cold it gets in winter? People got sick, children died, babies died.'
'Come on, let's go look at the museum,' said Juliet, taking Caroline's other hand. 'I bet you'd like to see the room where those sisters used to write their stories, wouldn't you? And the kitchen where they sat by the fire on winter evenings when the wind was wuthering and shaking the window panes.'
She gave a scary 'whoo' and Caroline's anxious frown was replaced by a tentative smile.
'Whoo,' she echoed and gave a little skip, swinging her arms between the two women.
Oliver brought up the rear.
The Parsonage. the Bronte Society brochure, cover
The parsonage reminded Caroline of Juliet and Alan's house, it had the same big windows with twelve panes of glass exactly the same size surrounded by white painted frames. It stood on a small rise, with grass and flower beds sloping down from the foundations into a flat garden planted with shrubs and flowers.
'See these?' said Juliet. 'They're called Canterbury bells. And these are hosta. They're all plants you could find when the Brontës lived here.'
'That was when Victoria was the Queen?'
'That's right.'
They climbed the steps and passed into the hallway. The furniture was old and the walls were hung with dark oil paintings. A grandfather clock ticked. A curved staircase with a polished wooden banister rose to the upper floor.
The first room they visited was Reverend Brontë's study.
'Patrick Brontë came to work here as curate in 1820.' Oliver took over as guide, pointing to a desk covered in books and papers. 'So, Princess Whatwhyhow, how many years ago was that?'
Caroline's lips moved silently.
'Quite a lot,' she said, eventually.
'Good answer,' said Oliver.
'Patrick was a good man in many ways,' said Juliet, 'He did a lot of things for the village, worked hard for the people of his parish, set up a Sunday school, tried to improve their standard of living and health care.'
'Was he a saint?'
'Well I suppose some people called him that. But it was hard on his children. Because he had a lot of work, they were usually left to their own devices. Which was lonely for them, but lucky for us, because this house is where the sisters wrote their books. Maybe, if they'd lived in a big city with lots to do and people to visit, Jane Eyre and Wuthering Heights would never have seen the light of day.'
In the dining room stood the table where the three sisters sat to write.
'Charlotte and Emily were the famous ones, but Anne wrote two fine books as well. They were all talented. They used to sit here and work together, then walk round the table reading out what they'd written that day.'
'They really loved each other, didn't they?'
'They did. And their brother too, in spite of his problems. He was a talented artist and a poet. We're going to see some of his paintings.'
Juliet decided to omit the part of the story where three of the siblings had died in quick succession, Branwell and Anne in 1848, Emily in 1849. Nor was she going to recount the sad reminiscences of Tabby, their faithful servant, describing how, after the other three were dead and buried, she used to listen with an aching heart to the footsteps of Charlotte in the room above, 'walking, walking on alone'.
'Right. The kitchen.'
Juliet ushered Caroline towards the door. Alexandra paused in front of a sofa that stood against one wall.
Oliver came across to stand behind her.
'This is where she died, Emily. According to Charlotte. She'd been having pains in her chest for several weeks but wouldn't see the doctor.'
She turned to look at him.
'How old was she?'
'Thirty. Only a few years younger than Mum.' He shook his head. 'Charlotte was devastated. She wrote 'moments so dark as these I have never known'. She's my favourite one of the sisters, Emily.'
'Because she died so tragically?'
'Huh, there was no shortage of tragic deaths. But she was the most solitary of all of the children, shy, didn't get on easily with people though apparently she was very kind-hearted. She was a creature of the moors. There are stories about how she could talk to animals, she used to bring them home, rabbits, birds, tend to their injuries. Like a vet. She reminds me a bit of our Cath, she used to be out of doors all the time when she was younger, we both did. Mum and Dad named her after Catherine, in Wuthering Heights, did you know that? Along with hundreds of other parents round here. Lots of Cathys in Yorkshire.'
nothing like a good book
'I've got a copy of Emily's poems back at the house if you want to read them?'
'I'd like that. It's a while since I've read any poetry. I used to be quite a fan. Wordsworth, Shelley, Keats.'
'Really?'
He hesitated, then began to recite, his voice little more than a whisper:
"…I am not doomed to wear
Year after year in gloom and desolate despair;
A messenger of Hope comes every night to me,
And offers, for short life, eternal liberty.
He comes with western winds, with evening's wandering airs,
With that clear dusk of heaven that brings the thickest stars;
Winds take a pensive tone, and stars a tender fire,
And visions rise and change which kill me with desire.'
He stopped, flushed, gave an embarrassed shrug.
'She called that one The Prisoner.'
'The Prisoner?'
'Yes…are you OK?'
Alexandra had gone deathly pale. She stared at Oliver. In the dimness of the room his eyes were a blazing blue. His jaw was shadowed by stubble, his curly hair sprang up from his head in darkly gleaming spirals. His face could have adorned a Renaissance painting, an angel bending over the manger, a nobleman hunting with his hawk in the Tuscan hills.
As though in a dream, she reached up and gently touched his cheek. The contact lasted less than a second, then she turned abruptly and left the room.
Oliver stood quite still.
Juliet and Caroline were in the kitchen. Caroline was frowning at the table where Emily used to bake at the same time as she studied her German lessons and made notes for her poems. She decided when she got back to school she was going to learn lots of foreign languages and write poetry.
Tree near Top Withens
'Over here there used to be a window,' said Oliver, coming up behind her and pointing. 'It's blocked up now, but you could look out of it, across the moors. Imagine what it was like on a winter's night, everything outdoors covered in snow, the fire crackling in the hearth, Emily making bread, Tabby telling stories.'
'Did they have a cat?'
'Ah,' said Juliet, looking helplessly at her son. 'I'm sure they did. Maybe Alan knows, lovey, we'll ask him when we get back.'
Caroline's favourite room was the children's study where they played when they were little. Branwell had a box of toy soldiers that looked like old-fashioned pegs painted red, blue and black. The four children used to make up fantastical stories about them, inventing an imaginary kingdom called Angria where the Duke of Wellington was the hero, fighting wars with different enemies. He and other characters had lots of adventures which the children wrote about in tiny books, using even tinier writing which needed a magnifying glass to read. It must have been nice to have sisters and a brother. But Teresa Knowles had three sisters and two brothers and they were always fighting with one another and getting punished by Mrs Knowles who sometimes ran after them with a rolling pin.
She was still thinking about brothers and sisters later that day. Picking up her pen she began to write in her notebook:
'Today we visited the Bronte Museum. It is in the old Parsnidge next to the graveyard. There are a lot of babies and other children buried in the churchyard. It was the Victorian age. You could die at any moment. The toilet was outside and you had to queue even if it was snowing. The best thing was the childrens notebooks. Aunt Juliet bought me a postcard of the Bronte sisters in the museum shop like the picture that you showed me. It was painted by Branwell he was not just a drunkerd but also a nice person. Everybody had a lot of brothers and sisters in those days. If I had a brother I would like him to be the same as Oliver. Arnie is a very nice baby but we haven't seen him this week. On Sunday Frank was cruel to him and pulled his arm and made him cry. Cath has promised to come over and put some desperate damson on my nails. She has rings on all her fingers even her thumb and in her nose and ears and is pretty. I would quite like her for a sister. The problem with having a brother and sister is they could get a disease and die at any minute. Perhaps it is better just to have a dog or a cat. I am really missing Rusty. Thank you for getting me this notebook Daddy.'
The Passage of Desire
Other blogs of mine relating to the Brontës can be found in the archives: March 2015, April 2016, January 2018 and July 2018.
Also on the same subject, check out author Helena Fairfax's November 21 blog, which links to another blog 😉 by Annika Perry. Let's hear it for the Brontës and their fans!
Here's a video (in spite of lots of background 'wuthering' at the beginning, all adds to the atmosphere !) by LucyTheReader, showing the moors, the churchyard and the museum.
Have a great reading weekend!
Posted on 23 November 2019 Categories ThoughtsTags Charlotte's little book, Haworth, the Brontë Society, the Brontes, The Passage of Desire, Yorkshire6 Comments
Keeping The Literary Lights Burning: Emily Bronte 30 July 1818–19 December 1848.
Happy birthday, Emily!
This weekend my feet may be in the Tarn but my head (and heart) is in northern England, more particularly in West Yorkshire where, 200 years ago, one of the greatest British writers was born. Wuthering Heights, her only novel, marked me profoundly as an adolescent and has continued to mark me ever since. She was one of the first feminist writers I read, along with her sisters, and George Eliot and Elizabeth Gaskell; she was an unrepentant rebel (Wuthering Heights hit the literary scene like a bad smell, it 'revolted many readers', was criticised for its 'coarseness of tone') and she wrote a stunning, tempestuous, enigmatic love story with the kick of a triple Moscow Mule on an empty stomach. Simone de Beauvoir famously wrote that when Cathy cries 'I am Heathcliff!' she is uttering the cry of every woman in love.
"I am Heathcliff!" (Learn 😉 )
In January this year I wrote :
'For many born in Yorkshire's West Riding, the Brontë legend enters our lives as naturally as the air we breathe.'
Inseparable from the Brontës and their writing are the moors:
It's hard to explain the fascination of these 'high, wild, desolate' places, chillingly bleak in winter when 'the four winds of heaven seemed to meet and rage together', but which, in late summer, are transformed into 'long swells of amethyst-tinted hills', 'all glorious with the purple bloom of the heather' contrasting with 'the tawny golden light…of summer evenings'.
After the death of all her siblings, Charlotte suffered from acute loneliness. Writing of her solitary walks across the moors, she said 'everything reminds me of the times when (the) others were with me… My sister Emily had a particular love for them, and there is not a knoll of heather, not a branch of fern, not a young bilberry leaf, not a fluttering lark or linnet, but reminds me of her. The distant prospects were Anne's delight, when I look round, she is in the blue tints, the pale mists, the waves and shadows of the horizon.'*
Haworth churchyard
In my last book, The Passage of Desire, there's a scene where Juliet and her son Oliver take their guests, Alexandra and seven-year-old daughter Caroline, to visit the Brontë Museum
"Caroline had been pestering for a visit to the museum. And so, one bright morning, they found themselves in the shade of the village churchyard on their way to the parsonage. The tower of St Michael and All Angels was just visible as they stepped into a forest of graves, wedged into every available inch of space, the headstones standing shoulder to shoulder like chessmen, some with pointed tops, some shaped like mitres, others representing stars or fleur-de-lys, or crowned with ornate pediments…..Thousands of bodies, it was said as many as forty thousand, lay together in this confined space, a reminder that the now pretty village of Haworth had once been a grim and insalubrious place, home to workers in the textile mills that spread across the valley, fed by the plentiful water pouring down from the rain-soaked moors.
This was not a peaceful resting place, like some (Alexandra) had visited. In spite of the fine day it was dark and chilly under the tall trees where rooks cawed. The graveyard was full of rustlings as the wind passed through the high branches and shook the stands of yew and ibex. White dandelion clocks floated in the unkempt grass. "
The Bronte Parsonage Museum
Fortunately, beyond the churchyard is the parsonage itself. It may seem rather cramped and primitive by today's standards, but it is a magical place, full of history, enchantment, inspiration, compassion, imbued by the spirit of those children who lived there and who gathered in the dining room to create their own imaginary universe.
They inhabited a self-contained world, mixing rarely with others, drawing, sketching, inventing plays and fantasy worlds. Voracious readers of whatever they could lay their hands on, from contemporary magazines to the poetry of Wordsworth and Byron and the novels of Sir Walter Scott, they created stories and poems of their own, their fertile imaginations fed by the written word and the 'purple-black' moors…
When Branwell's decline into alcoholism and dementia forced the three sisters to find a way to maintain the family finances, it was in this same room that they sat to work on the novels of Currer, Ellis and Acton Bell:
Juliet decided to omit the part of the story where three of the siblings had died in quick succession, Branwell and Anne in 1848, Emily in 1849. Nor was she going to recount (to seven-year-old Caroline) the sad reminiscences of Tabby, their faithful servant, describing how, after the other three were dead and buried, she used to listen with an aching heart to the footsteps of Charlotte in the room above, 'walking, walking on alone'."
The Brontë Society
Today the memory of the Brontës burns bright through the work they left behind, but also through the remarkable efforts of one of the world's oldest and proudest literary societies, the Brontë Society, celebrating its 125 birthday this year, responsible among other things for running the fascinating 91-year-old Brontë Parsonage Museum.
This year the focus is on 'Brontë 200: Emily 1818-1848', with a rich and diverse programme of literature, music, visual art, exhibitions, talks, children's activities, workshops, author interviews, walks, films and numerous other events.
And so, dear readers and fellow-passionates, to finish today's blog, I'm going to put on my commercial hat and invite book lovers and especially Brontë lovers to think about joining The Brontë Society (no, I don't get a discount or a free bag of chips), and of taking advantage of the numerous perks that membership confers: free admission to the Museum for one year, regular issues of the members' magazine, priority booking for events, access to the dedicated area of the website and access to many Brontë-related documents (not to mention a warm glow as you sign the cheque). Yearly membership is between £12.50 and £25 depending on age… how many skinny lattes is that exactly? ) And if you're feeling generous you can add a donation and the glow gets brighter.
Best of all, take a trip to those 'glorious wild moors, which in after days (the children) loved so passionately' and see for yourself what it's all about.
"long swells of amethyst-tinted hills…"
Let's keep those literary lights burning!
*many quotations in the January blog exerpts (in blue) are from the wonderful Elizabeth Gaskell
The Passage of Desire is the prequel to The French Summer Novels, and is set in Haworth.
http://tinyurl.com/gmno7uy
http://tinyurl.com/j269qsy
Posted on 28 July 2018 Categories ThoughtsTags bicentenary, Elizabeth Gaskell, Emily Bronte, Haworth, the Brontë sisters, the Brontë Society, The Passage of Desire, the Yorkshire moors4 Comments


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Hadamard single-pixel imaging versus Fourier single-pixel imaging
Zibang Zhang, Xueying Wang, Guoan Zheng, and Jingang Zhong
Zibang Zhang,1 Xueying Wang,1 Guoan Zheng,2 and Jingang Zhong1,3,*
1Department of Optoelectronic Engineering, Jinan University, Guangzhou 510632, China
2Biomedical Engineering, University of Connecticut, Storrs, CT, 06269, USA
3Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications, Jinan University, Guangzhou 510632, China
*Corresponding author: tzjg@jnu.edu.cn
Z Zhang
X Wang
G Zheng
J Zhong
Zibang Zhang, Xueying Wang, Guoan Zheng, and Jingang Zhong, "Hadamard single-pixel imaging versus Fourier single-pixel imaging," Opt. Express 25, 19619-19639 (2017)
Get PDF (11045 KB)
Computational-weighted Fourier single-pixel imaging via binary illumination (OE)
Deringing and denoising in extremely under-sampled Fourier single pixel imaging (OE)
Projector-defocusing rectification for Fourier single-pixel imaging (OE)
Imaging Systems and Displays
Computational imaging
Spatial light modulators
Microscopy (110.0180)
Photography (110.5200)
Computational imaging (110.1758)
Image reconstruction techniques (110.3010)
Original Manuscript: June 26, 2017
Revised Manuscript: July 31, 2017
Manuscript Accepted: July 31, 2017
2. Comparison of theory
3. Comparison of experiment
Figures (17)
Equations (12)
Single-pixel imaging which employs active illumination to acquire spatial information is an innovative imaging scheme and has received increasing attentions in recent years. It is applicable to imaging at non-visible wavelengths and imaging under low light conditions. However, single-pixel imaging has once encountered problems of low reconstruction quality and long data-acquisition time. Hadamard single-pixel imaging (HSI) and Fourier single-pixel imaging (FSI) are two representative deterministic model based techniques. Both techniques are able to achieve high-quality and efficient imaging, remarkably improving the applicability of single-pixel imaging scheme. In this paper, we compare the performances of HSI and FSI with theoretical analysis and experiments. The results show that FSI is more efficient than HSI while HSI is more noise-robust than FSI. Our work may provide a guideline for researchers to choose suitable single-pixel imaging technique for their applications.
© 2017 Optical Society of America
The earliest example of single-pixel imaging might be the flying-spot camera patented by Paul Nipkow in 1884. P. Nipkow provided a method for encoding and transmitting image information using a rotating Nipkow disk. Laser confocal scanning microscopy [1], optical coherence tomography [2], ultrasonic endoscope [3], and scanning electron microscopy [4] are also examples of single-pixel imaging which perform raster scanning in the spatial domain. Contemporary single-pixel imaging, which uses a time-varying structured illumination and an appropriate computer algorithm, originates from ghost imaging [5–17]. Ghost imaging was initially considered as a quantum effect [5] but later Bennink et al. demonstrated that it can be implemented with a classical source [6]. Computational ghost imaging [7–17] allows one to capture a scene using a single-pixel (or bucket) detector. Objects to be imaged are under spatially and temporally varying illuminations. The illumination patterns are typically generated using a spatial light modulator (SLM). The single-pixel detector is used to collect the corresponding light signal for each illumination pattern. The desired image is computationally reconstructed by correlating the illumination patterns with the detected signals.
Single-pixel imaging techniques [14–35] do not need to use any pixelated detector for light signal detection. This advantage brings single-pixel imaging a potential capability of solving some challenges in conventional imaging. For example, single-pixel imaging scheme allows one to build a low-cost imaging system that can work at non-visible wavelengths. It should be noted that pixelated detectors are commonly expensive or even unavailable at most non-visible wavelengths. Single-pixel imaging may also have the advantage of imaging at low light conditions. This is because, in comparison with pixelated detectors, single-pixel detectors with large active area are easier to fabricate and more sensitive to light.
Inherited from ghost imaging, single-pixel imaging was initially based on a statistical model, which can be evident by the use of random patterns for illumination. The random patterns form an overcomplete non-orthogonal set. Consequently, it requires a great number of measurements (much larger than pixel counts) and long data-acquisition time for recording signals. For instance, Sun et al. used 106 random patterns to reconstruct an image with a resolution of 256×192 pixels [15]. Even with so many measurements, the quality of images reconstructed by single-pixel imaging is hardly comparable with the quality of images obtained by conventional pixelated-detector-based imaging. Long-data acquisition time and low reconstruction quality limit the applicability of this innovative imaging scheme. Compressive sensing [7,9,14,16–18,20,21] has been adopted to reduce measurements, but it is at the expense of computational time.
The recently proposed deterministic model based techniques [18–35] can well tackle these problems of long data acquisition time and low reconstruction quality. These techniques use deterministic orthogonal basis patterns, instead of non-orthogonal random patterns, for illumination. Hadamard single-pixel imaging (HSI) [18–29] and Fourier single-pixel imaging (FSI) [30–34] are two representative single-pixel imaging techniques that use a deterministic model. HSI uses Hadamard basis patterns for illumination while FSI uses Fourier basis patterns. The use of basis patterns for illumination brings two advantages. The first advantage is perfect reconstruction in principle. We refer perfect reconstruction to the ability that allows images to be accurately recovered and the property that an imaging model itself would not introduce errors. Or in other words, a technique that allows perfect reconstruction is able to produce a reconstruction exactly the same as the ground truth in an ideal case (such as noiseless simulation). Illumination using basis patterns enables perfect reconstruction, because the basis patterns form a complete orthogonal set. Basis patterns illumination allows one to acquire the spatial information of object image in a transformation domain and recover the object image via the corresponding inverse transform. In principle, the image can be reconstructed without noticeable difference from the ground truth, when is fully sampled in the transformation domain. This feature solves the problem of low reconstruction quality in ghost imaging. The second advantage is measurement reduction. Natural images give a sparse representation in some transformation domains, such as Hadamard, Fourier, discrete cosine [35] or wavelet [36,37] domain, allowing one to reconstruct a sharp image with under-sampled data. This feature solves the problem of long acquisition time. As such, deterministic model based techniques well tackle the problems that are inherited from ghost imaging.
In this paper, we theoretically and experimentally compare these two representative deterministic model based single-pixel imaging techniques–HSI and FSI, in terms of principles, imaging efficiency, noise robustness, and etc. This comparison shows the commons and the differences between HSI and FSI. The comparison also presents the advantages and disadvantages of the both techniques.
2.1 Principle of HSI and FSI
HSI is based on Hadamard transform [38–40]. HSI acquires the Hadamard spectrum of the object image and reconstructs the object image by applying an inverse Hadamard transform. Hadamard spectrum is composed by a group of Hadamard coefficients. Each coefficient corresponds to a unique Hadamard basis pattern. To obtain a Hadamard coefficient, one can project the corresponding Hadamard basis pattern(s) onto the object and use a single-pixel detector to measure the resultant light intensity. The single-pixel light intensity measurement is mathematically equivalent to the inner product between the Hadamard basis pattern(s) and the object. As such, the Hadamard spectrum can be reconstructed based on the single-pixel measurements. The two-dimensional Hadamard transform H{} of an image I(x,y) is defined as [38]
(1)I˜H(u,v)=H{I(x,y)}=∑x=0M−1∑y=0N−1I(x,y)(−1)q(x,y,u,v),
(x,y) is the coordinate in the spatial domain
(2)q(x,y,u,v)≡∑i=0n−1[gi(u)xi+gi(v)yi],
where (u,v) is the coordinate in the Hadamard domain, n=log2N, and
(3)g0(u)≡un−1g1(u)≡un−1+un−2g2(u)≡un−2+un−3.⋮gn−1(u)≡u1+u0
The terms ui, vi, xi, and yi are the binary representations of u, v, x, and y respectively . For example,
(4)(u)decimal=(un−1un−2⋯u1u0)binary.
A frequency interpretation can be given to the Hadamard spectrum–along each row/column of the Hadamard spectrum the frequency is called the number of changes in sign. However, as Hadamard basis patterns are not strictly periodic, the word "sequency" is used to designate the number of sign changes [38]. Hadamard transform is only applicable for input images of size N-by-N, where N, N/12, or N/20 is a power of 2.
A Hadamard basis pattern PH(x,y) can be obtained by applying an inversed Hadamard transform to a delta function δH(u,v),
(5)PH(x,y)=12[1+H−1{δH(u,v)}],
where H−1{} denotes an inverse Hadamard transform and
(6)δH(u,v)={1,u=u0,v=v00,otherwise.
The sample Hadamard basis pattern shown in Fig. 1 is derived by substituting u=5 and v=5 into Eq. (5). Thus, it has 5 sign changes each row and 5 sign changes each column.
Fig. 1 Illustration of differential HSI, 4-step FSI, and 3-step binary FSI.
Differential HSI is an embodiment of HSI, allowing each Hadamard coefficient H(u,v) to be acquired in a manner of differential measurement [19–27]. Differential HSI is conducive to suppression of noise. As illustrated in Fig. 1, to acquire a coefficient H(u,v), differential HSI takes two measurements. The one measurement is acquired by projecting a Hadamard basis pattern PH(x,y) and the other measurement is by its inverse [1−PH(x,y)]. The coefficient H(u,v) is obtained by using the two corresponding measurements
(7)H(u,v)=D+1−D−1,
where D+1 and D−1 are measurements corresponding to the illuminations of PH(x,y) and [1−PH(x,y)], respectively. Hadamard coefficients are real-valued and the number of Hadamard coefficients is the same as that of image pixels. Fully sampling an N×N-pixel image using differential HSI takes 2N2 measurements.
FSI is based on Fourier transform. FSI acquires the Fourier spectrum the object image and reconstructs the object image by applying an inverse Fourier transform. Fourier spectrum is composed by a group of Fourier coefficients. Each coefficient corresponds to a unique Fourier basis pattern (also known as sinusoidal pattern or fringe pattern). To obtain a Fourier coefficient, one can project the corresponding Fourier basis pattern(s) onto the object and use the single-pixel detector to measure the inner product between Fourier basis patterns and the object. As such, the Fourier spectrum can be reconstructed from the single-pixel measurements. Fourier transform was proposed in the late 1800s by Joseph Fourier and has been widely used in a number of fields. It allows any signal to be decomposed into a set of orthogonal sinusoidal waveforms of different frequencies. For example, images as two-dimensional signals are allowed to be broken down into a combination of sinusoidal intensity patterns. The two-dimensional Fourier transform F{} of an image I(x,y) is defined as
(8)I˜F(u,v)=F{I(x,y)}=∑x=0M−1∑y=0N−1I(x,y)exp[−j2π(uxM+vyN)],
where (x,y) is the coordinate in the spatial domain and (u,v) is the coordinate in the Fourier domain. A Fourier basis pattern PF(x,y) can be obtained by applying an inverse Fourier transform to a delta function δF(u,v,φ),
(9)PF(x,y)=12[1+real{F−1{δF(u,v,φ)}}],
where real{} denotes the real part, F−1{} denotes an inverse Fourier transform, and
(10)δF(u,v,φ)={exp(jφ),u=u0,v=v00,otherwise.
4-step FSI and 3-step FSI are two embodiments of FSI, using the 4-step phase-shifting formula Eq. (11) and the 3-step phase-shifting formula Eq. (12), respectively. Both embodiments allow each Fourier coefficient F(u,v) to be acquired in a manner of differential measurements. As illustrated by Fig. 1, 4-step FSI and 3-step FSI acquire each Fourier coefficient with 4 and 3 measurements, respectively. Please note that Fourier coefficients are complex-valued. 4-step FSI allows one to acquire each complex-valued Fourier coefficient F(u,v) by projecting four patterns PF(x,y,0), PF(x,y,π/2), PF(x,y,π) and PF(x,y,3π/2), and using the corresponding four measurements D0, Dπ/2, Dπ, and D3π/2:
(11)F(u,v)=(Dπ−D0)+j(D3π/2−Dπ/2).
Also note that PF(x,y,π) is the inverse of the pattern PF(x,y,0); PF(x,y,3π/2) is the inverse of the pattern PF(x,y,π/2). The number of Fourier coefficients is the same as that of image pixels (M×N). With the prior knowledge that the Fourier spectrum of any real-valued image is conjugated symmetric, fully sampling an M×N-pixel image using 4-step FSI takes 2×M×N measurements. It can be seen that the 4-step FSI is essentially a differential method of measurement. FSI can also be conducted by employing the 3-step phase-shifting formula. The 3-step FSI acquires each complex-valued Fourier coefficient with 3 measurements,
(12)F(u,v)=(2D0−D2π/3−D4π/3)+3j⋅(D2π/3−D4π/3),
where D0, D2π/3, and D4π/3 are the measurements corresponding to the illumination patterns of PF(x,y,0), PF(x,y,2π/3), and PF(x,y,4π/3), respectively. Evident by Eq. (12), 3-step FSI is also a differential method of measurement, but in an asymmetric form. As the 4-step FSI does, the 3-step FSI has the property of noise suppression, but its performance is not as good as the 4-step FSI. It is because the 4-step FSI is a differential method of measurement in a symmetric manner while the 3-step is in an asymmetric manner. Fully sampling an M×N-pixel image using 3-step FSI takes 1.5×M×N measurements. In comparison with 4-step FSI, 3-step reduces 25% measurements.
In short, FSI and HSI are single-pixel imaging techniques based on basis scan and theoretically allow perfect reconstruction for any images in noiseless situations.
2.2 Basis patterns generation
The core of single-pixel imaging is to employ active illumination to acquire the spatial information of a target object. Instead of using random patterns, basis-scanning single-pixel imaging techniques use deterministic basis patterns for illumination. Figure 1 shows the comparison between the Hadamard and Fourier basis patterns. The difference can be summarized as follows: 1) Hadamard basis patterns are binary and mosaics look-alike while Fourier basis patterns are grayscale and fringes look-alike; 2) Hadamard basis patterns only have horizontal and vertical features while Fourier basis patterns have horizontal, vertical, and oblique features; 3) Fourier basis patterns are strictly periodical while Hadamard basis patterns are not.
The applicability and the performance of these basis-scanning single-pixel imaging techniques rely on the effectiveness and efficiency of basis patterns generation. Thus, it is necessary to discuss the methods of basis patterns generation for HSI and FSI. Hadamard basis patterns are binary (black-and-white), which makes HSI naturally suitable for single-pixel imaging systems based on a digital micro-mirror device (DMD). As DMD is a binary device, HSI can benefit from the high-speed binary illumination ability given by a DMD. Additionally, binary Hadamard basis patterns would not lead to quantization errors or gamma (nonlinear) distortion. However, to our best knowledge, Hadamard transform does not carry clear physical meaning, which makes Hadamard basis patterns almost impossible to be generated by a physical means. The applicability of HSI relies on the use of SLM. In other words, HSI would likely have difficulties when SLMs are unavailable at certain spectral regions.
On the other hand, Fourier basis patterns are naturally grayscale. It leads to the fact that FSI is not able to take the benefit of a high-speed SLM directly. For instance, DMDs work much slower in the grayscale mode. A state-of-art DMD can display ~20,000 binary patterns per second but can only display ~250 8-bit (256 quantization levels) grayscale patterns per second. Thus, FSI suffers from slower illumination rate and therefore longer data-acquisition time than HSI. In addition, using any digital device to generate Fourier basis patterns would cause quantization errors. When the number of quantization levels is too low, the resulting quantization errors would lead to pronounced image quality degradation. Recently, Zhang et al. proposed binary FSI [29], a workaround that uses binary Fourier basis patterns for illumination. Binary Fourier basis patterns are generated by upsampling and then dithering the grayscale Fourier basis patterns. The shortcoming of this approach is at the expense of reduced spatial resolution. Although Fourier basis patterns are not perfectly compatible with DMDs, fortunately Fourier transform is a natural operator and has physical meaning, which enables Fourier basis pattern to be generated by some physical means. For example, an ideal thin lens can be used as a Fourier transform engine with which the Fourier transform of an object image can be obtained at the back focal plane of the thin lens. Even without a thin lens, the Fourier transform of an object image can be approximately obtained by the far-field diffraction pattern, which is subject to Fraunhofer diffraction. Thus, one can generate Fourier basis patterns by using the interference of two plane waves, which adds applicability to FSI, especially for the cases that SLMs are expensive or even not available.
In short, FSI is more flexible and variant than HSI in terms of illumination patterns generation while HSI can benefit much more from the high-speed binary DMDs.
2.3 Robustness to noise
Both HSI and FSI are robust to dark noise and read-out noise in principle, because, as evident by Eq. (1) and Eq. (8), Hadamard transform and Fourier transform are global transformation. Global transformation has a property that each point (coefficient) in the transformation domain is a weighted sum of all points in the spatial domain and each point (image pixel) in the spatial domain is also a weighted sum of all points in the transformation domain. In other words, global transformation implies that each pixel in a reconstructed image is contributed by all measurements and such an averaging process allows evening out errors in measurement. Additionally, the average flux per each Hadamard/Fourier pattern is independent of the number of pixels, and each measurement collects on average half of the total flux.
In terms of quantization errors, HSI outperforms FSI. It is because Fourier basis patterns continuously vary in space and magnitude. Thus, quantization errors will be caused when using digital devices [such as DMD or Liquid Crystal on Silicon (LCoS)] to generate Fourier basis patterns. Such errors would degenerate the quality of final reconstruction. On the other hand, Hadamard basis patterns are naturally in a discrete manner. Digital devices are able to generate quantization error-free Hadamard basis patterns.
2.4 Efficiency
We refer efficient single-pixel imaging to a technique that allows one to reconstruct a sharp image with a small number of measurements. Additionally, highly efficient single-pixel imaging enables time-lapse imaging. Since the throughput of a single-pixel imaging system is inherently limited by the readout rate of the single-pixel detector, it is of critical importance to improving the efficiency of single-pixel imaging techniques.
The efficiency of a basis-scanning single-pixel imaging technique depends on how well the utilized transformation concentrates the image energy. If a transformation is able to highly concentrate the image energy within a waveband (i.e., a small number of coefficients have large magnitudes), one can simply measure those large-magnitude coefficients and omit the rest to improve efficiency.
For natural images, energy is usually uniformly distributed in the spatial domain. Both Hadamard transform and Fourier transform have the ability to concentrate the image energy near the origin of their transformation domain. Thus, both HSI and FSI are able to reconstruct an imaging under Nyquist conditions by sampling coefficients with large magnitude. As will be quantitatively demonstrated in the following experimental comparison section, for natural images, Fourier transform gives a more condensed representation than Hadamard transform does. In other words, FSI outperforms HSI in terms of energy concentration.
Moreover, the physical meaning of Fourier transform gives it the capability of characterizing the impulse-response of some optical system. Optical transfer function (OTF), defined as the Fourier transform of the point spread function, shows how different spatial frequencies are handled by the system. For most optical systems, the OTF is an equivalent low-pass spatial filter. As a result, the spatial information that an imaging system can collect is low-pass filtered.
It can be seen that the characteristics of natural images and optical imaging system concentrate the image energy at the lower frequencies range of the Fourier domain. As such, it leads to rapid convergence in terms of reconstruction quality for FSI to sample the Fourier spectrum along the increment of spatial frequency.
In some diffraction-limited situations such as microscopy, the achievable spatial resolution is determined by the cut-off spatial frequency given by the diffraction limit. In this case, the optical system acts as a low-pass filter with a finite ability to resolve details. In mathematical terms, a diffracted-limited system sets a spatial cutoff frequency f0 in the Fourier domain. Only the spatial information that falls into the circular low-frequency band with a radius of f0 can be acquired through the system. Thus, the approach that FSI samples the Fourier spectrum along a circular path and stops at the cutoff frequency is the most effective for a diffraction-limited system in principle. If the spatial cut-off frequency of the system is given, FSI allows one to sample the circular low-frequency band only. Even if the spatial cut-off frequency is not given, FSI allows one to sample the Fourier domain along a circular path until the sampled energy is lower than a certain threshold. On the contrast, Hadamard basis patterns are actually step functions whose bandwidth is infinite. The diffraction-limited system applies low-pass filtering to the Hadamard basis patterns, resulting in blur. Consequently, undersampled reconstructions in HSI would be degraded. For HSI, the lower cut-off frequency is, the more remarkable degradation will be.
Lower spatial frequency components are typically of much larger magnitude than higher spatial frequency components, as shown in Fig. 1. This prior knowledge implies a simple but efficient sampling strategy that only low-frequency components are needed to be sampled in the data-acquisition process.
3.1 Numerical simulations
We firstly compare the performance of both techniques through numerical simulations using MATLAB. In the presented simulations, we focus on the quality of reconstructed images by using both techniques, especially when the images are undersampled. It should be emphasized that the throughput of single-pixel imaging systems is, in general, lower than conventional imaging systems and undersampling is a straightforward approach to reduce the number of measurements. Undersampling refers to acquire only the low-frequency coefficients and omit the high-frequency ones, given the prior knowledge that most energy of natural images is concentrated in low-frequency bands. Since sampling strategies may change the quality of the reconstructed images, we use three different sampling strategies for HSI and FSI without losing generality. The sampling strategies refer to the path along which coefficients are to be acquired. The sampling strategies in comparison are shown in Fig. 2. We note that the origin for Fourier spectra is located at the center of the pictures while the origin for Hadamard spectra is located at the left-top corner of the pictures. Therefore, Fourier spiral path is equivalent to Hadamard square path; Fourier diamond path is equivalent to Hadamard zig-zag path; Fourier circular path is equivalent to Hadamard circular path. The resolution of all reconstructed images in the presented numerical simulations is 64×64 pixels.
Fig. 2 Illustration of six sampling strategies used in our simulations. The pictures in the first row are sampling paths, according to which coefficients are acquired from low-frequency bands (blue) to high-frequency bands (red). The pictures in the second row are sample spectra acquired along the corresponding path. Spectra shown are with the sampling ratio of 50%.
Three different and characterized input images are used in the comparison, the 1951 USAF test chart pattern, 'Siemens star' target pattern, and the Lena image. The 1951 USAF test chart pattern is a binary pattern consisting of groups of three bars with dimensions from big to small. The bars are along vertical and horizontal directions. The 'Siemens star' target pattern is also a binary pattern. It provides multiple contrast measurements from a wide range of spatial frequencies. Different from the USAF 1951 test chart pattern, the 'Siemens star' target pattern has many oblique features. The Lena image is one of the most widely used natural image in imaging system tests and has multiple gray levels. We use peak signal-to-noise ratio (PSNR), structural similarity index (SSIM), and power ratio to quantitatively evaluate the quality of reconstructed images. Power ratio is a quantity which can evaluate the energy concentration ability, defined as power of the acquired spectrum to that of the complete spectrum ratio. Please note that, for Tables 1–3, the data in bold are the overall best results.
Table 1. Quantitative comparison results for USAF 1951 test chart
Table 2. Quantitative comparison results for 'Siemens star'
Table 3. Quantitative comparison results for 'Lena'
As the results shown in Fig. 3 and Table 1, FSI with the diamond path gives the best reconstruction for the USAF 1951 test chart pattern. With the diamond path, Fourier coefficients on both spatial frequency axes are acquired preferentially. Those Fourier coefficients corresponding to horizontal and vertical fringe patterns highly correlate with the features of the resolution target (that is, horizontal and vertical bars). Thus, FSI with diamond sampling strategy achieves better reconstruction than the others for the same sampling ratio.
Fig. 3 Comparison results for USAF 1951 test chart pattern reconstruction by HSI and FSI for different sampling ratios.
As the results shown in Fig. 4 and Table 2, FSI with the circular path gives the best reconstruction for the 'Simens star' image. The results by HSI, as they present, are with mosaic artifacts, especially for the oblique features. It is because, Hadamard basis patterns are mosaic look-alike, but lack of oblique features.
Fig. 4 Comparison results for "Siemens star" target pattern reconstruction by HSI and FSI for different sampling ratios.
As the results shown in Fig. 5 and Table 3, FSI outperforms HSI for the 'Lena' image which is a natural image. However, both techniques introduce observable artifacts when sampling ratio is too low. HSI introduces mosaic artifacts while FSI introduces ringing artifacts.
Fig. 5 Comparison results for 'Lena' image reconstruction by HSI and FSI for different sampling ratios.
Without loss of generality, we test all images in the USC-SIPI image database [41]. The database consists of 632 images and all the images are categorized into four groups—textures, aerials, miscellaneous, and sequences. Similarly, for every single image, we evaluate reconstruction quality of the six sampling strategies using PSNR, SSIM, and power ratio. The statistical comparison results are derived by counting the overall best for each image. The results are shown in Fig. 6. Based on the comparison results, it is found that FSI has better performance than HSI in terms of reconstruction quality in the situations of undersampling. It is also found that for natural images reconstruction circular path is the best sampling strategy for FSI and zig-zag path is the best sampling strategy for HSI.
Fig. 6 Statistical comparison results for all four different kinds of images in the USC-SIPI Image Database by HSI and FSI. (a) aerials, (b) miscellaneous, (c) sequences, and (d) textures. The bars indicate the image count of overall best for six different sampling strategies.
Furthermore, we consider the case that the imaging system is diffraction-limited. We assume that the OTF of the system is an ideal low-pass filter whose cut-off frequency is f0=0.25 pixel−1, indicated by the dash circles in Fig. 7. The 'Baboon' image is used as the ground truth and we reconstruct the image by HSI and FSI under different sampling ratios. HSI employs the zig-zag sampling path while FSI employs the circular sampling path. As OTF is commonly represented in the Fourier space, we give the Fourier spectrum for all reconstructions, even for those by HSI, so as to show how the OTF affects the reconstruction. As the results shown in Fig. 7, the quality of reconstructions by FSI converges after the sampling zone reaches the boundary set by the cut-off frequency. For the results by HSI, although the recovered spatial information fills up the low-pass band, the value of the recovered Fourier coefficients is inaccurate when undersampled. The coefficients are corrected gradually as the sampling ratio increases. As indicated by the curves of PSNR, SSIM, and RMSE, the convergence of HSI is lower than that of FSI.
Fig. 7 Results of diffraction-limited system simulation. The OTF is assumed to be an ideal low-pass filter whose cut-off frequency is f0.
The simulations above demonstrate that quality of sub-Nyquist sampled images depends on the energy concentration ability of the utilized transformation and the sampling strategy. For natural images, Fourier transform has better energy concentration ability than Hadamard transform, because the correlation between a Fourier basis pattern and a natural image is larger than that between a Hadamard pattern and a natural image. Or in other words, Fourier basis patterns are more similar to the natural images than Hadamard basis patterns. Thus, FSI outperforms HSI in terms of reconstruction quality under sub-Nyquist sampling conditions.
We further compare the both techniques in terms of robustness to noise. Without loss of generality, we use both the 'Lena' and the 'Cameraman' images for the test. To simulate cases of different noise levels, we add white Gaussian noise to the raw data (that is, measurements D) resulting in different SNRs. The addition of white Gaussian noise is implemented by using the built-in function awgn() of MATLAB. We jointly use PSNR, SSIM, and root mean square error (RMSE) to evaluate the reconstruction quality. The PSNRs, SSIMs and RMSEs are computed with the ground truth as reference. The results are shown in Figs. 8 and 9 and highly consistent. According to the results, HSI is more robust to FSI. It turns out that there's a tradeoff between energy concentration and robustness against noise.
Fig. 8 Noise-robustness comparison using the 'Lena' image. (a) PSNR, (b) SSIM, (c) RMSE, and (d) reconstructed images under different SNRs.
Fig. 9 Noise-robustness comparison using the 'Cameraman' image. (a) PSNR, (b) SSIM, (c) RMSE, and (d) reconstructed images under different SNRs.
Furthermore, we examine the effect of quantization error on the quality of reconstructed image in FSI. We quantize the Fourier basis patterns under different levels. For instance, for quantization levels Q, the Fourier basis patterns are quantized by round[Q⋅PF(x,y)]/Q. The input image used in this simulation is the 'Pepper' image. Figure 10 shows the reconstruction for quantization levels 2, 4, 8, 16, …, 512. As the figure shows, when the number of quantization levels is 2, which equivalent to binarize the Fourier basis patterns by thresholding, it would make the reconstruction drenched into periodic artifacts. When the number of quantization levels is 4, the quantization errors result in a grid overlay on the reconstruction. The grid fades away as the number of quantization levels increases and becomes unnoticeable when the number of quantization levels is 64. It should be noted that SLMs commonly have 256 quantization levels
Fig. 10 Quantization errors test for FSI. The reconstruction results for different quantization levels (a) 2, (b) 4, (c) 8, (d) 16, (e) 32, (f) 64, (g) 128, (h) 256, and (i) 512. (j) shows the ground truth.
3.2 Experiments
We further compare HSI and FSI with experimental data. The first experiment is single-pixel photography using a commercial digital projector (Acer K750) for spatial light illumination. The experimental set-up is shown in Fig. 11. The projector switches pattern every 0.2 seconds. A photodiode (HAMAMATSU S1227-1010BR) is used as a single-pixel detector. The active area of the photodiode is 1 × 1 cm2. The photodiode is driven by a customized amplifier circuit. We don't use any lenses in front of the photodiode for light coupling and the photodiode detects the back-scattered light from the scene directly. The resultant electric signals are delivered to a data acquisition board [National Instruments USB-6343 (BNC)]. The digitalized data is finally collected by the computer. The methods in comparison are differential HSI and 4-step FSI.
Fig. 11 Experimental set-up for single-pixel photography where a commercial digital projector is used for illumination.
The results are shown in Fig. 12. The resolution of the reconstructed images is 256 × 256 pixels. As the figure shows, the FSI presents more clear and sharp reconstructions than HSI does in the case of undersampling. The advantage of FSI is relatively observable for the sampling ratio lower than 10%. The results in this experiment coincide with those derived in the numerical simulations.
Fig. 12 Comparison results of single-pixel photography. Scale bar = 4 cm.
The second experiment is fast single-pixel imaging. As the experimental set-up shown in Fig. 13, we employ a DLP development kit to achieve high-speed illumination. The DLP development kit is equipped with a 0.7-inch DMD. The DMD has 1024 × 768 micro mirrors, each of which is 13.6 × 13.6 μm2 in size. The light source is a 3-watt white LED. The DMD operates at 2,000 Hz, allowing 2,000 binary patterns projection per second. The patterns generated by the DMD are projected onto the scene through a lenses system. The lenses system is removed from a commercial digital projector (Toshiba T-95). The back-scattered light is detected using a photomultipliers tube (Thorlabs PMM01). The photomultipliers tube has a self-owned collecting lens for better light coupling. The resultant electronic signals are transferred to the computer via a data acquisition board [National Instruments USB-6343 (BNC)]. The object to be imaged is some stationery and a piece of A4 paper printed an enlarged 1951 USAF resolution test pattern. The object is under illumination by basis patterns. The methods in comparison are differential HSI 3-step binary FSI, and 4-step binary FSI. The reason why we use binary FSI in this experiment for comparison is that the original FSI is not able to directly use a high-speed DMD for high-speed imaging. It is because the original FSI uses grayscale patterns for illumination, while even an edge-cutting DMD can only display ~250 8-bit grayscale patterns per second, which is a shortcoming of the original FSI.
Fig. 13 Experimental set-up for fast single-pixel photography where a DMD development kit is used for illumination.
The resolution of illumination patterns is 256 × 256 pixels. For binary FSI, the patterns are upsampled using 'bicubic' interpolation so that the resolution of the images becomes 512 × 512 pixels, twice of the original. Floyd-Steinberg dithering is then applied to the upsampled Fourier basis patterns. For HSI, the Hadamard basis patterns are upsampled to be 512 × 512 pixels using 'nearest' interpolation. The comparison results are presented in Fig. 14.
Fig. 14 Comparison results for fast single-pixel photography. Scale bar = 4 cm.
Based on the comparison results, binary FSI outperforms HSI in terms of reconstruction quality in the case of a small number of measurements. In the case of 1,000 measurements, heavy ringing artifacts present in the results of FSI while HSI gives a mosaic reconstruction. 3-step FSI is the only technique that can reconstruct the horizontal lines on the pencil holder, showing its advantage in extremely undersampled cases. In the case of 4,000 measurements, 3-step binary FSI gives better reconstruction, which is evident by that all five pencils in the holder on the right become distinguishable. In the case of 8,000, the results by both FSI techniques are satisfactory, except that there still ringing artifacts on the background while the result by HSI is of mosaic, especially for the oblique structures such as the pencil in the left pencil holder. HSI outperforms FSI in terms of uniform pattern reconstruction. The background in the reconstruction by HSI is free of artifacts or noises. In the case of 30,000 measurements, the result by HSI looks as good as those by FSI. In the case of 98,304, the result by HSI is even better than those by FSI in terms of noise level. The noise on the background of the results by FSI becomes noticeable, which is due to the quantization errors.
In short, in the case of a small number of measurements, FSI outperforms HSI for FSI has better energy concentration ability than HSI. In the case of a large number of measurements, HSI has better reconstruction quality than binary FSI. It is because binary FSI introduces quantization errors when generates binary Fourier basis patterns using dithering.
The third experiment is microscopy where we use a digital light projector (Texas Instruments LightCrafter Display 4710 evaluation module) along with a tube lens and an objective lens [Olympus 10X objective (NA = 0.4)] for illumination patterns generation. The experiment set-up is shown in Fig. 15. The DMD of the projector consists of 1920×1080 micro mirrors whose pitch is 5.4 microns. A Si amplified photodetector (Thorlabs PDA-100A) is used as a single-pixel detector that collects the transmitted light through the object. The model of the data acquisition board used in this experiment is National Instruments USB-6363 (BNC). The object to be imaged is a USAF1951 resolution target (Ready Optics #2015A). Please note that to make full use of the area the DMD, we use 4 × 4-pixel binning in this experiment. The resolution of illuminations patterns is 256 × 256 pixels and each pattern uses 1024 × 1024 mirrors for illumination. The illumination patterns switch every 0.2 seconds.
Fig. 15 Comparison results for single-pixel microscopy.
Figures 16 and 17 show the comparison results for single-pixel microscopy. Please note that Fig. 17 shows the partial enlargement of the results in Fig. 16.
Fig. 16 Comparison results for single-pixel microscopy. The enlarged partial image (in the red box) are shown in Fig. 17.
Fig. 17 The partial enlargement of the images shown in Fig. 16.
As the results shown, FSI presents clearer and sharper reconstruction than HSI in the case of undersampling, especially when the sampling ratio is under 10%. For instance, the digits and the bars of the 6th group become distinguishable for the results by FSI. For the full-sampled cases, HSI presents as good results as FSI does.
We present a systematic comparison between the HSI and the FSI in principle and experiments. The overall comparison is summarized in Table 4. According to the principle analysis and the experimental results, we conclude that the FSI is more efficient than the HSI as Fourier transform better concentrates image energy than Hadamard transform does. Additionally, the 3-step FSI allows measurement reduction in the case of differential measurement. Thus, for applications where efficiency is concerned, the FSI is the primary selection. We also conclude that the HSI has better noise robustness than the FSI and is perfectly suitable for DMD-based single-pixel imaging systems. Therefore, for applications where image quality or accuracy is concerned, the HSI is the primary selection.
Table 4. Comparison between HSI and FSI
National Natural Science Foundation of China (NSFC) (61475064); National Science Foundation (NSF) DBI 1555986; National Institutes of Health (NIH) R21EB022378 and R03EB022144.
The authors thank Dr. Shiping Li for her help with the experimental equipment preparation, and Qinqiu Fang for linguistic assistance.
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26. M. J. Sun, M. P. Edgar, D. B. Phillips, G. M. Gibson, and M. J. Padgett, "Improving the signal-to-noise ratio of single-pixel imaging using digital microscanning," Opt. Express 24(10), 10476–10485 (2016). [CrossRef] [PubMed]
27. N. Huynh, E. Zhang, M. Betcke, S. Arridge, P. Beard, and B. Cox, "Single-pixel optical camera for video rate ultrasonic imaging," Optica 3(1), 26–29 (2016). [CrossRef]
28. B. Lochocki, A. Gambín, S. Manzanera, E. Irles, E. Tajahuerce, J. Lancis, and P. Artal, "Single pixel camera ophthalmoscope," Optica 3(10), 1056–1059 (2016). [CrossRef]
29. L. Martínez-León, P. Clemente, Y. Mori, V. Climent, J. Lancis, and E. Tajahuerce, "Single-pixel digital holography with phase-encoded illumination," Opt. Express 25(5), 4975–4984 (2017). [CrossRef] [PubMed]
30. Z. Zhang, X. Ma, and J. Zhong, "Single-pixel imaging by means of Fourier spectrum acquisition," Nat. Commun. 6, 6225 (2015). [CrossRef] [PubMed]
31. Z. Zhang and J. Zhong, "Three-dimensional single-pixel imaging with far fewer measurements than effective image pixels," Opt. Lett. 41(11), 2497–2500 (2016). [CrossRef] [PubMed]
32. Z. Zhang, X. Wang, and J. Zhong, "Fast Fourier single-pixel imaging using binary illumination," arXiv preprint arXiv:1612.02880 (2016).
33. L. Bian, J. Suo, X. Hu, F. Chen, and Q. Dai, "Efficient single pixel imaging in Fourier space," J. Opt. 18(8), 085704 (2016). [CrossRef]
34. H. Jiang, S. Zhu, H. Zhao, B. Xu, and X. Li, "Adaptive regional single-pixel imaging based on the Fourier slice theorem," Opt. Express 25(13), 15118–15130 (2017). [CrossRef]
35. B. L. Liu, Z. H. Yang, X. Liu, and L. A. Wu, "Coloured computational imaging with single-pixel detectors based on a 2D discrete cosine transform," J. Mod. Opt. 64(3), 259–264 (2017). [CrossRef]
36. M. Alemohammad, J. R. Stroud, B. T. Bosworth, and M. A. Foster, "High-speed all-optical Haar wavelet transform for real-time image compression," Opt. Express 25(9), 9802–9811 (2017). [CrossRef] [PubMed]
37. S. Mallat, A Wavelet Tour of Signal Processing: The Sparse Way (Academic, 2008).
38. W. K. Pratt, J. Kane, and H. C. Andrews, "Hadamard transform image coding," Proc. IEEE 57(1), 58–68 (1969). [CrossRef]
39. J. A. Decker Jr., "Hadamard-Transform Image Scanning," Appl. Opt. 9(6), 1392–1395 (1970). [CrossRef] [PubMed]
40. J. Gourlay, P. McOwan, D. G. Vass, I. Underwood, and M. Worboys, "Time-multiplexed optical Hadamard image transforms with ferroelectric-liquid-crystal-over-silicon spatial light modulators," Opt. Lett. 18(20), 1745–1747 (1993). [CrossRef] [PubMed]
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J. H. Shapiro, "Computational ghost imaging," Phys. Rev. A 78(6), 061802 (2008).
W. L. Chan, K. Charan, D. Takhar, K. F. Kelly, R. G. Baraniuk, and D. M. Mittleman, "A single-pixel terahertz imaging system based on compressed sensing," Appl. Phys. Lett. 93(12), 121105 (2008).
J. H. Shapiro and B. I. Erkmen, "Ghost imaging: from quantum to classical to computational," Adv. Opt. Photonics 2(4), 405–450 (2009).
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F. Ferri, D. Magatti, L. A. Lugiato, and A. Gatti, "Differential ghost imaging," Phys. Rev. Lett. 104(25), 253603 (2010).
B. Sun, S. S. Welsh, M. P. Edgar, J. H. Shapiro, and M. J. Padgett, "Normalized ghost imaging," Opt. Express 20(15), 16892–16901 (2012).
S. S. Welsh, M. P. Edgar, R. Bowman, P. Jonathan, B. Sun, and M. J. Padgett, "Fast full-color computational imaging with single-pixel detectors," Opt. Express 21(20), 23068–23074 (2013).
B. Sun, M. P. Edgar, R. Bowman, L. E. Vittert, S. Welsh, A. Bowman, and M. J. Padgett, "3-D Computational imaging with single-pixel detectors," Science 340(6134), 844–847 (2013).
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M. F. Duarte, M. A. Davenport, D. Takhar, J. N. Laska, T. Sun, K. F. Kelly, and R. G. Baraniuk, "Single-pixel imaging via compressive sampling," IEEE Signal Process. Mag. 25(2), 83–91 (2008).
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N. Radwell, K. J. Mitchell, G. M. Gibson, M. P. Edgar, R. Bowman, and M. J. Padgett, "Single-pixel infrared and visible microscope," Optica 1(5), 285–289 (2014).
M. P. Edgar, G. M. Gibson, R. W. Bowman, B. Sun, N. Radwell, K. J. Mitchell, S. S. Welsh, and M. J. Padgett, "Simultaneous real-time visible and infrared video with single-pixel detectors," Sci. Rep. 5(1), 10669 (2015).
S. S. Welsh, M. P. Edgar, R. Bowman, B. Sun, and M. J. Padgett, "Near video-rate linear Stokes imaging with single-pixel detectors," J. Opt. 17(2), 025705 (2015).
M. J. Sun, M. P. Edgar, G. M. Gibson, B. Sun, N. Radwell, R. Lamb, and M. J. Padgett, "Single-pixel three-dimensional imaging with time-based depth resolution," Nat. Commun. 7, 12010 (2016).
M. J. Sun, M. P. Edgar, D. B. Phillips, G. M. Gibson, and M. J. Padgett, "Improving the signal-to-noise ratio of single-pixel imaging using digital microscanning," Opt. Express 24(10), 10476–10485 (2016).
N. Huynh, E. Zhang, M. Betcke, S. Arridge, P. Beard, and B. Cox, "Single-pixel optical camera for video rate ultrasonic imaging," Optica 3(1), 26–29 (2016).
B. Lochocki, A. Gambín, S. Manzanera, E. Irles, E. Tajahuerce, J. Lancis, and P. Artal, "Single pixel camera ophthalmoscope," Optica 3(10), 1056–1059 (2016).
L. Martínez-León, P. Clemente, Y. Mori, V. Climent, J. Lancis, and E. Tajahuerce, "Single-pixel digital holography with phase-encoded illumination," Opt. Express 25(5), 4975–4984 (2017).
Z. Zhang, X. Ma, and J. Zhong, "Single-pixel imaging by means of Fourier spectrum acquisition," Nat. Commun. 6, 6225 (2015).
Z. Zhang and J. Zhong, "Three-dimensional single-pixel imaging with far fewer measurements than effective image pixels," Opt. Lett. 41(11), 2497–2500 (2016).
Z. Zhang, X. Wang, and J. Zhong, "Fast Fourier single-pixel imaging using binary illumination," arXiv preprint arXiv:1612.02880 (2016).
L. Bian, J. Suo, X. Hu, F. Chen, and Q. Dai, "Efficient single pixel imaging in Fourier space," J. Opt. 18(8), 085704 (2016).
H. Jiang, S. Zhu, H. Zhao, B. Xu, and X. Li, "Adaptive regional single-pixel imaging based on the Fourier slice theorem," Opt. Express 25(13), 15118–15130 (2017).
B. L. Liu, Z. H. Yang, X. Liu, and L. A. Wu, "Coloured computational imaging with single-pixel detectors based on a 2D discrete cosine transform," J. Mod. Opt. 64(3), 259–264 (2017).
M. Alemohammad, J. R. Stroud, B. T. Bosworth, and M. A. Foster, "High-speed all-optical Haar wavelet transform for real-time image compression," Opt. Express 25(9), 9802–9811 (2017).
S. Mallat, A Wavelet Tour of Signal Processing: The Sparse Way (Academic, 2008).
W. K. Pratt, J. Kane, and H. C. Andrews, "Hadamard transform image coding," Proc. IEEE 57(1), 58–68 (1969).
J. A. Decker., "Hadamard-Transform Image Scanning," Appl. Opt. 9(6), 1392–1395 (1970).
J. Gourlay, P. McOwan, D. G. Vass, I. Underwood, and M. Worboys, "Time-multiplexed optical Hadamard image transforms with ferroelectric-liquid-crystal-over-silicon spatial light modulators," Opt. Lett. 18(20), 1745–1747 (1993).
http://sipi.usc.edu/database/
Alemohammad, M.
Andrés, P.
Andrews, H. C.
Arridge, S.
Artal, P.
Baraniuk, R. G.
Baron, D.
Beard, P.
Bennink, R. S.
Bentley, S. J.
Betcke, M.
Bian, L.
Bosworth, B. T.
Bowman, A.
Bowman, R.
Bowman, R. W.
Boyd, R. W.
Buxton, J. L.
Chan, W. L.
Chang, W.
Charan, K.
Chen, F.
Clemente, P.
Climent, V.
Cox, B.
Dai, Q.
Davenport, M. A.
Decker, J. A.
DiMagno, E. P.
Duarte, M. F.
Durán, V.
Edgar, M. P.
Egami, R.
Erkmen, B. I.
Fernández-Alonso, M.
Ferri, F.
Flotte, T.
Foster, M. A.
Fujimoto, J. G.
Gambín, A.
Gatti, A.
Gibson, G. M.
Gourlay, J.
Green, P. S.
Gregory, K.
Hattery, R. R.
Hee, M. R.
Horisaki, R.
Hu, X.
Huang, D.
Hunt, J.
Huynh, N.
Irles, E.
Jiang, H.
Jonathan, P.
Kane, J.
Kelly, K. F.
Krishna, S.
Lamb, R.
Lancis, J.
Laska, J. N.
Li, X.
Lin, C. P.
Lipworth, G.
Liu, B. L.
Liu, X.
Lochocki, B.
Lugiato, L. A.
Ma, X.
Magatti, D.
Manzanera, S.
Martínez-León, L.
Matsui, H.
McOwan, P.
Mitchell, K. J.
Mittleman, D. M.
Montoya, J.
Mori, Y.
Nixon, W. C.
Oatley, C. W.
Padgett, M. J.
Pease, R. F. W.
Phillips, D. B.
Pittman, T. B.
Pratt, W. K.
Puliafito, C. A.
Radwell, N.
Regan, P. T.
Sarvotham, S.
Schuman, J. S.
Sergienko, A. V.
Shapiro, J. H.
Shih, Y. H.
Shrekenhamer, D.
Sleasman, T.
Stinson, W. G.
Strekalov, D. V.
Stroud, J. R.
Suarez, J. R.
Sun, B.
Sun, M. J.
Sun, T.
Suo, J.
Swanson, E. A.
Tajahuerce, E.
Takhar, D.
Tanida, J.
Torres-Company, V.
Underwood, I.
Vass, D. G.
Vittert, L. E.
Wakin, M. B.
Watts, C. M.
Webb, R. H.
Welsh, S.
Welsh, S. S.
Wilson, D. A.
Worboys, M.
Wu, L. A.
Xu, B.
Yang, Z. H.
Zhang, E.
Zhang, Z.
Zhao, H.
Zhong, J.
Zhu, S.
Adv. Electron. Electron Phys. (1)
Adv. Opt. Photonics (1)
Appl. Opt. (3)
IEEE Signal Process. Mag. (1)
J. Mod. Opt. (1)
J. Opt. (2)
Nat. Commun. (2)
Nat. Photonics (1)
Optica (3)
Phys. Rev. A (2)
Proc. IEEE (1)
Proc. SPIE (1)
Rep. Prog. Phys. (1)
Sci. Rep. (1)
Fig. 7 Results of diffraction-limited system simulation. The OTF is assumed to be an ideal low-pass filter whose cut-off frequency is f 0 .
Table 1 Quantitative comparison results for USAF 1951 test chart
Table 2 Quantitative comparison results for 'Siemens star'
Table 3 Quantitative comparison results for 'Lena'
Table 4 Comparison between HSI and FSI
(1) I ˜ H ( u,v )=H{ I( x,y ) }= ∑ x=0 M−1 ∑ y=0 N−1 I( x,y ) ( −1 ) q( x,y,u,v ) ,
(2) q( x,y,u,v )≡ ∑ i=0 n−1 [ g i ( u ) x i + g i ( v ) y i ] ,
(3) g 0 ( u )≡ u n−1 g 1 ( u )≡ u n−1 + u n−2 g 2 ( u )≡ u n−2 + u n−3 . ⋮ g n−1 ( u )≡ u 1 + u 0
(4) ( u ) decimal = ( u n−1 u n−2 ⋯ u 1 u 0 ) binary .
(5) P H ( x,y )= 1 2 [ 1+ H −1 { δ H ( u,v ) } ],
(6) δ H ( u,v )={ 1, u= u 0 ,v= v 0 0, otherwise .
(7) H( u,v )= D +1 − D −1 ,
(8) I ˜ F ( u,v )=F{ I( x,y ) }= ∑ x=0 M−1 ∑ y=0 N−1 I( x,y )exp[ −j2π( ux M + vy N ) ] ,
(9) P F ( x,y )= 1 2 [ 1+real{ F −1 { δ F ( u,v,φ ) } } ],
(10) δ F ( u,v,φ )={ exp( jφ ), u= u 0 ,v= v 0 0, otherwise .
(11) F( u,v )=( D π − D 0 )+j( D 3π/2 − D π/2 ).
(12) F( u,v )=( 2 D 0 − D 2π/3 − D 4π/3 )+ 3 j⋅( D 2π/3 − D 4π/3 ),
Quantitative comparison results for USAF 1951 test chart
Sampling ratio
PNSR (dB)
Hadamard
circular 11.00 12.45 13.17 13.64 14.25 15.45 19.42 27.24
square 10.93 12.39 13.04 13.49 13.84 15.09 16.68 20.94
spiral 11.37 12.66 13.28 13.91 14.51 18.48 22.19 26.59
SSIM (%)
circular 7.2 30.0 41.1 48.3 57.2 67.2 83.1 93.2
square 9.3 28.4 39.7 48.5 51.4 69.0 74.8 86.4
spiral 9.9 31.8 44.3 54.8 62.7 84.1 91.6 95.9
Power (%) Hadamard
Fourier circular 7.7 20.0 29.2 36.6 45.1 69.0 84.2 95.1
diamond 8.3 20.7 30.6 40.4 48.7 73.1 86.9 95.2
Quantitative comparison results for 'Siemens star'
circular 8.01 10.24 11.12 12.21 14.02 16.17 18.21 23.70
square 7.98 9.94 10.83 11.55 13.84 15.29 17.36 20.98
spiral 8.07 11.84 14.46 15.93 17.07 21.28 24.91 30.11
circular 10.0 43.1 52.4 62.2 72.2 82.1 87.0 93.2
square 10.3 38.4 49.2 59.3 71.3 82.5 84.9 91.4
spiral 11.0 54.0 75.0 81.3 84.3 93.9 97.1 98.7
Quantitative comparison results for 'Lena'
Fourier circular 17.6 35.3 46.3 53.6 59.8 76.8 87.8 95.3
diamond 18.1 35.4 46.4 53.8 59.4 76.6 87.7 95.1
Comparison between HSI and FSI
Original FSI
Binary FSI
Perfect reconstruction Yes Yes No
Measurements for each coefficient (direct sampling) 1 1 1
Measurements for each coefficient (differential sampling) 2 1.5 (3-step); 2 (4-step) 1.5 (3-step); 2 (4-step)
Grayscale levels Binary Multiple Binary
Robust to dark / read-out noise Yes Yes Yes
Robust to quantization errors Yes No Yes
Reconstruction for arbitrary-size image No Yes Yes
Patterns generation methods Spatial light modulator Spatial light modulator / Interference of planar waves Spatial light modulator

redpajama_set_name: RedPajamaCommonCrawl


text:
TransDigm completes acquisition of DART Aerospace
TransDigm Group Incorporated announced today it has successfully completed its acquisition of DART Aerospace ("DART" or "the Company"), a portfolio company of Greenbriar Equity Group, L.P., for approximately $360 million. TransDigm financed the acquisition with cash on hand. The acquisition of DART was previously announced on March 14, 2022.
DART is headquartered in Montreal, Quebec. The Company is a leading provider of highly engineered, unique helicopter mission equipment solutions that predominantly service civilian aircraft. The Company is expected to generate approximately $100 million in pro forma revenues for the calendar year ending December 31, 2022. Approximately 95% of DART's revenues are derived from proprietary products and about 80% of DART's revenues comes from the aftermarket. The products have a strong presence across major commercial rotary-wing platforms as well as select applications for defense and safety services. The Company employs approximately 400 people and operates from four primary facilities in Hawkesbury, Ontario; Portland, Oregon; Fort Collins, Colorado and Chihuahua, Mexico.
Contact details from our directory:
Dart Aerospace Limited Design Services, Aerial Firefighting Equipment, Fabricating Services, Helicopter Assemblies, Machining Services, Air Filters, Air Conditioning Equipment, Cable Cutters, Aircraft Security Equipment, Cargo Liners, Cushioning Foam, Evacuation Systems, Floor Coverings, Helicopter Floats, Helicopter Landing Gear, Life Rafts, Mirrors, Passenger Seating, Seat Belts, Windshields
TransDigm Group Incorporated
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text:
Home / Books / NWS Welcomes Our New Contributor – Center for Security Policy
NWS Welcomes Our New Contributor – Center for Security Policy
By Yikes on March 9, 2010
… (The ground rules of the meeting were off the record; the book will be out soon, though, so stay tuned for much more about it.) The author underscored that for the sort of improved GOP we need, "national security must be Job #1."
Unfortunately, as noted in this space two weeks ago, it seems that for some prominent Republican/conservatives, to paraphrase the "Open Borders" crowd, national security is a job Americans don't want to do anymore.
Consider the scant and mostly euphemistic treatment of the issue in the new Conservative Action Project manifesto dubbed the Mount Vernon Statement, released with much fanfare on February 17. Not particularly objectionable, but a pale comparison to the principled and robust opposition to the totalitarian ideology of the day, Soviet Communism, enunciated fifty years before by William F. Buckley, Jr. and other founders of the modern conservative movement in America.
Then, there was the Conservative Political Action Conference (CPAC) in which, apart from several noteworthy addresses, the official agenda was largely bereft of any discussion of the threats to our nation, constitution and society arising from today's totalitarian ideology – what authoritative Islam calls "Shariah."
Most immediately, the final selection is underway for the Tea Party-inspired "Contract from America." The idea is that activists and ordinary citizens are being polled to fashion a list of priorities for their elected officials. The only problem is that not one of the twenty options from which the public is being asked to chose addresses national security, Shariah-inspired jihad, terrorism, homeland security or any other aspect of the common defense. For people who are supposed to be attached to the Constitution– which gives priority to that federal responsibility– this seems to be a most curious oversight.
Another explanation for the low-balling, or outright ignoring, of national security is the influence of some of the more libertarian members of the conservative movement. Their sentiments are exemplified and aggressively advanced, mostly behind the scenes, by Grover Norquist. Norquist is best known for his anti-tax activism as president of Americans for Tax Reform but, over the past 12 years, he has become increasingly associated with policies and initiatives that are strikingly at odds with the national security convictions and practices of the man he – and virtually all other conservatives – so admire: Ronald Reagan.
For example, Norquist recently wrote an open letter that charged with "scaremongering" those who opposed the Obama administration's efforts to close Guantanamo Bay, move terrorist mastermind Khalid Sheikh Mohammed and his fellow 9/11 conspirators to trial in New York City and open a new Gitmo North in Illinois. He has inveighed for years against the Patriot Act, promoted "open borders" and sponsored a neo-isolationist organization called the American Conservative Defense Alliance. One of the Alliance's fellows, a disgruntled ex-CIA officer named Philip Giraldi, presented a paper at a 2010 CPAC panel entitled "Why Real Conservatives are Against the War on Terror." Giraldi told the audience that, "Fear has been the key to the door for expansion of government and government powers and the people in charge in Washington have seized the opportunity. It has also eroded the liberties that have defined us as a nation."
As bloggers Michelle Malkin and Pamela Geller, among others, have noted, Norquist has also been a sponsor of efforts to promote in the name of GOP "inclusion" individuals and organizations associated with the Muslim Brotherhood. He seems indifferent to the Brotherhood's self-declared mission to "destroy Western civilization from within" or the close alignment between many of his policy recommendations and the interests of the Brothers and other Shariah adherents who seek such an outcome.
As it happens, Grover Norquist has lately taken to promoting more debates in American politics. He has done so together with such prominent Leftists as Katrina vanden Heuvel, publisher of the Nation magazine and co-author of Taking Back America – and Taking Down the Radical Right. As he put it recently in a pas de deux with her on NPR, "In a debate, both sides make their case in real time. Debates are better than speeches; debates are competition….Debates are alive; arguments are tested and honed."
Well, it seems to me the Republican Party and the conservative movement urgently need a debate about whether the sorts of views Norquist espouses should be those adopted by the Right – or even simply allowed to suppress the adoption of more sensible, Reaganesque policies – rather than making the latters' pursuit Job #1.
Therefore, I challenge Grover Norquist to engage in such a public debate, as soon as possible, in the interest of ensuring that the sorts of arguments about the common defense that he has made, both publicly and privately, about the direction of the GOP and America are tested and, if found wanting, repudiated before they do further, real harm to both.
Frank J. Gaffney, Jr. is the President of the Center for Security Policy, a columnist for the Washington Times and host of the nationally syndicated program, "Secure Freedom Radio," heard in Washington at 9 p.m. weeknights on WTNT 570 AM.
To access the embedded links please go to:
http://www.centerforsecuritypolicy.org/p18325.xml
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This July Jealous and Charming Baker will be heading to the fields of Suffolk for Latitude festival 2018. The Jealous team will be live printing in the Faraway Forest and Charming Baker is holding a talk in the Music and Film Arena.
Jealous were thrilled to be invited back to Rokesly Junior School for our annual Art Week Project with the kids of Year 4.
With previous projects including a protest in the school playground, a giant jigsaw and finally collaborating with Ai Wei Wei.
So who better to call in for our 2018 project, than our long-time collaborator and friend, Mr Ben Eine.
For this project, we created a 1 colour screenprint in Eine's iconic Circus font which read 'Imagination'. We then armed the kids with every colour of Sharpie to collaborate with Eine to add handfinished colour.
And best of all? We got to have our annual school dinner! Huge thanks to all the kids and staff at Rokesly for a brilliant day!
Ben Eine and Kaspersky Lab are holding the two day Pop-Up 'The Data Dollar Store' at Old Street Station where you will be able to get the new Ben Eine' 'K' screenprint edition along with other Ben Eine exclusive merchandise.


On July 27th, Seneca Falls Police arrested Rachael R. Winfield, age 34, of Seneca Falls, for criminal possession of controlled substance in the 7 degree(4 Counts), criminal use of paraphernalia in the 2 degree, and aggravated unlicensed operation in the 2 degree following a traffic stop on SR 414 in the Town of Seneca Falls.
During the stop, it was discovered that Winfield's driving privileges in NYS were suspended for failure to answer summons. Winfield was also found to be in possession of various controlled substances inside the vehicle.
Winfield was arraigned in the Town of Seneca Falls Court and remanded to Seneca County Correctional Facility in lieu of $500 cash/$1,000 insurance bond. She is to reappear in the Town of Seneca Falls Court at a later date and time.


Here at FIAT of Vancouver, we like to help our customers and other drivers take good care of their vehicle safety systems. One safety system that is absolutely essential is the brake system. Well cared for and provisioned brakes can make the difference between drivers staying in control of their vehicles or losing it.
Brakes are special devices that mount on each vehicle tire. They come in two major varieties that include disc brakes and drum brakes. Disc brakes are considered to be the superior brake technology, and vehicles that use disc brakes on all wheels often indeed have greater stopping power.
In order to keep brakes in proper operating condition, they need regular service from professional personnel. That said, brakes can and do fail at any time, and drivers should keep a close eye out for some telltale signs. The signs include unexplained leakage of brake fluid, the brake pedal going all the way to the floor when pressed, and strange noises emanating from the wheel area. Also, any loss of braking force or sponginess in pedals should set off warning signs.


Good morning. We are here in Victoria, Texas where we spent the night in a Walmart parking lot. This is a huge parking lot. We had no problem finding a spot away from the crowds. We are also along the curb where we were able to put the bedroom slide out without any problems. That's always nice.
We only drove 304 miles yesterday, but it was steady rain almost the entire day. Plus, driving through Houston during that rain didn't help, nor did the construction cement blocks, which Clyde hates with a passion, that went on for miles and miles. It is still raining this morning. Hopefully it will have had enough by the time we are ready to leave. I know I have.
We also tried to fill up with propane again. We stopped at a Flying J, pulled up to the propane tank and Clyde went in to inquire about filling us up. When he came back he said you won't believe this, the guy won't come out in the rain. So no propane again. I'm not sure if it was a safety issue or if he just didn't want to get wet. Thankfully our friend told us where to get our needed propane when we get down to Harlingen. He says it's an easy in and easy out. That's one less thing to worry about.


One of the common rebuttals we see to Lyoness' Ponzi scheme is the cashback side of the business.
Originally offered through Lyoness itself, the cashback scheme was rebranded as CashBack World last year.
Following the Gaming Board's decision to ban and then uphold Lyoness' ban in Norway, the company has filed a second appeal.
In their second appeal, Lyoness reveals some interesting statistics regarding Cashback World card adoption and use.
Since inception, the cashback side of Lyoness has served to facilitate the core of the business, that is affiliates investing in units and then recruiting others who do the same.
Bundled with that is cashback, which here and there generates additional units, which allows affiliates to receive ROI payments slightly faster.
Ask anyone in Lyoness working the unit Ponzi though, and they'd be lying if they didn't confirm affiliate investor recruitment generates ROI much faster than shopping.
Which is important, considering that for 2017 Lyoness claimed to have 175,000 Cashback World members to 17,000 affiliates.
In most MLM companies that'd be an impressive retail to affiliate ratio. But bear in mind Cashback World membership is free and there's no obligation to spend.
Indeed, many merchants who have signed on as affiliates hand Cashback World cards out like candy, in an attempt to push through their own units toward a ROI payout faster.
Lyoness has not stated how many times each individual member used their benefit card 2017, and it is unclear how many Cashback World members are still active.
2017 saw significant growth of Lyoness' Ponzi across Italy, which began to taper off around April this year.
No doubt 2018 figures for Cashback World card usage among non-affiliates would tell a very different story, which is what the Gaming Board is getting at.
In any event, without knowing the total spend of non-affiliates on shopping, one can't calculate how much retail money was pumped into Shopping Units.
Typically Lyoness affiliates who sign up believing they'll be able to generate ROIs through shopping, soon realize that takes years.
It is far quicker to convince others to sign up as affiliates and invest, leading to the majority of revenue paid out on Shopping Units ROIs being sourced from new affiliates (hence the Ponzi nature of the business).
As part of their investigation the Gaming Board also requested a revenue breakdown.
Lyoness refused to provide the data and failed to 'provide sufficient reasons for not being able to supply current accounting for the company'.
Received figures from Lyoness show that revenue from loyalty cashback shopping does not provide the 17,000 Norwegian affiliates the number of shopping points they need to receive ROI payments.
With all signs pointing to Lyoness being a pyramid/Ponzi hybrid, this is precisely what the Gaming Board concluded in their initial investigation and upheld against Lyoness' first appeal.
According to the Lottery Authority's assessment, the number of participants in Cashback World and Lyconet is less important in the assessment of whether Lyoness is an illegal pyramid-like sales system.
Our assessment revealed Lyoness is a pyramid-like sales system in which remuneration is paid to qualify for the opportunity to earn income, due in part to the fact that others are recruited into the sales system, and not the sale or consumption of goods, services or other benefits.
Data received from Lyoness shows that revenue from Cashback World in 2016 was limited and that revenues came from selling discount coupons and shares (units) in Lyconet.
Remember, the Gaming Board's analysis is based on data submitted by Lyoness itself.
The Gaming Board rejected Lyoness' first appeal on May 31st.
A second appeal was filed and again rejected by the Gaming Board on July 19th.
As per internal procedures, Lyoness' second appeal has been forwarded to the Complaints Board for review and final decision.
Update 13th February 2019 – On February 12th, 2019, the Norwegian Lottery Board announced it had rejected Lyoness' second appeal.
As of January 26th, 2019, Lyoness has been permanently banned in Norway.
Cashback World card usage is low because very few retailers have signed up to it. The big name retailers that are listed on the CBW site like TESCO, M&S, BOOTS, B&Q, JOHN LEWIS, NIKE, HARRODS, COSTA, etc, are NOT merchants of CBW and do not accept their cards.
CBW buy the Love2shop giftcards (and others) at a discount, resell them back to their members at FULL price and then give back a tiny percentage of that discount as 'cashback'.
The cards can then be SPENT at any of the big retailers listed, but CBW omit that tiny detail – not to mention the fact that they're breaking Love2shops etc T&C's by reselling!
The smaller retailers are signing up to CBW – which costs them hundreds of pounds- because they think the big stores are members. So they are indirectly contributing to the giftcards that are spent in the BIG stores, taking away business from them!
Woking Council are still operating this scam and refuse to discuss it. The local MP has written to tell me that Woking can't possibly be involved in a scam and to write to the council!
In their second appeal Lyoness tried to raise the "OMG look at our partnerships!" nonsense, and they even rattled off a few retailers in Norway (presumably well-known locally).
The Gaming Board dismissed the claims because there was zero evidence of official partnerships provided.
Can't provide evidence of partnerships when all you're doing is shucking discounted gift cards at full price to your affiliates.
Lyoness – promising business model or snowball system?
Anyone who recruits himself as a "marketer" at his next contact person pays 100, 800 or 2500 € depending on the "starter package"!
As a marketer himself, you have the task of recruiting new members with these starter packages.
Otherwise, this system has no sense, except people (or friends = not a good idea) to pull money out of your pocket.
If you remain unsuccessful, you never see your own invested money again, so you have lost your nerves and valuable time!
P.S. Who denies this is itself the victim or a cheater!
The second video is from the German TV station ZDF and warns against snowball systems, gift circles and pyramid schemes. The lawyer also gives tips there on how Germans who joined Lyoness can get out of their contract.
The print run of BILD in the second quarter of 2018 was around 2.24 million copies. Of these, 1.64 million copies were sold.
The BILD newspaper is published by Axel-Springer-Verlag and, despite a decline in circulation, is still the daily newspaper with the largest circulation in Germany.


text:
FactoryGirl.define do
  factory :activity do
    content "MyText"
user nil
  end

end

redpajama_set_name: RedPajamaGithub