Answers.Body: <p>I don't own this scanner, but <a href="https://www.wolverinedata.com/assets/downloads/MovieMaker_PRO_V_3.0_Manual_.pdf" rel="nofollow noreferrer">looking at the specs</a>, it appears to record in MJPEG mode, scanning one frame at a time.</p>
  <p>The MJPEG codec records each frame of video as a JPEG image.  So each frame is compressed using JPEG, which is a lossy compression process.</p>
  <p>It then (I think?) has some software which can take the large MJPEG files and compress them further using mp4 h264? compression.</p>
  <p>MJPEG is a bit like a flick book of JPEG images - each one is compressed individually - there is no compression across multiple frames.  This means it takes up more space than mpeg-4 compression which does analyse across frames, and so can compress videos further.</p>
  <p>With all lossy compression systems, the more detail there is an image, the harder it is to compress it efficiently.  So if an image has lots of speckles and noise on it (like old film often does), this will either make the file much larger, or if the compressor is trying to target a given file size, the areas of low detail will become blocky.</p>
  <p>What <em>doesn't</em> tend to happen with video compression is added noise.  By noise, I mean randomised pixels at different brightnesses or colours to the desired signal.  Noise tends to be an analogue artefact (e.g. <a href="https://en.wikipedia.org/wiki/Film_grain" rel="nofollow noreferrer">grain in film</a> or <a href="https://en.wikipedia.org/wiki/Noise_(video)" rel="nofollow noreferrer">transmission noise</a> (&quot;snow&quot;) in an analogue tv picture).  Digital compression systems are terrible at compressing noisy images because every pixel is different (look at <a href="https://www.youtube.com/watch?v=P_Oh7HizY5I&amp;ab_channel=bstore" rel="nofollow noreferrer">this HBO logo</a> as a good example).</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-02T07:37:16.770Z
Answers.Text: Thank you so much for answering, I wasn't sure anybody would. According to [this](https://forum.videohelp.com/threads/390464-Restoring-8mm-and-Super-8mm-transfers) user who bought the exact same scanner and had one of his MP4 files analyzed (its the 5th post down) using an automated service, the scanner uses the AVC codec aka h.264. However, according to the link of the user manual you posted, if you look on page 3 of the PDF, under features, it simply says that it encodes using "MPEG-4."
Answers.UserDisplayName: Friedrich Bauer
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-02T07:37:26.793Z
Answers.Text: When the manual says "MPEG-4," do they really mean h.264 given that h.264 is sometimes called MPEG-4 Part 10?
Answers.UserDisplayName: Friedrich Bauer
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-02T07:41:32.210Z
Answers.Text: Video files have wrappers and codecs. The .mp4 part of the file name refers to the wrapper. You can have many different codecs inside a video file- eg different ones for audio and video tracks. But mp4 files most commonly use h264 as the codec.
Answers.UserDisplayName: tomh
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-02T07:43:28.537Z
Answers.Text: A lot of other things will affect the quality of the transfer, not least the optical quality of the signal path - eg the size and quality of the lens and the sensor. The bandwidth limitation of how the files are encoded will also affect the quality. Without having one to play with it’s tricky to offer any more advice.
Answers.UserDisplayName: tomh
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-02T08:49:02.597Z
Answers.Text: Help me understand your 4th paragraph. I thought MJPEG and MPEG-4 were two opposing compression standards, and so it wouldn't be advisable to use them both together, but the scanner's manual clearly states that the machine uses MPEG-4, with no mention of MJPEG, and in your reply you state that the scanner uses MJPEG, so which is it? Are you saying that this particular scanner uses both MJPEG _and_ MPEG-4 compression together?
Answers.UserDisplayName: Friedrich Bauer
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-02T09:53:53.647Z
Answers.Text: I may be wrong about that - initially I thought I saw MJPEG mentioned on the amazon page, but looking now I can only see mp4 mentioned
Answers.UserDisplayName: tomh
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-03T05:18:20.800Z
Answers.Text: I just have a few more questions. Correct me if I'm wrong, but assuming this device encodes video using h.264, isn't h.264 mainly a delivery codec, rather than a codec meant to allow for editing in post? For instance, I already know this device doesn't allow you to turn off auto-white balance, although it does allow you to adjust exposure somewhat, so if I ever wanted to adjust the white balance in post, wouldn't the use of this codec make it hard to adjust things like white balance, exposure, or even do any kind of color correction without the whole process being destructive to the MP4 file?
Answers.UserDisplayName: Friedrich Bauer
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-03T08:31:22.343Z
Answers.Text: Yes you are right. It’s definitely not designed for use by editors or anyone who wants to manipulate footage afterwards.
Answers.UserDisplayName: tomh
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-04T05:17:36.683Z
Answers.Text: Part 1: OK, h.264 is not a codec designed for editing, but if the scanner gets the auto-white balance wrong, is it even worth trying to edit the files in post, or do you consider it a hopeless endeavor?
Answers.UserDisplayName: Friedrich Bauer
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-04T05:18:02.567Z
Answers.Text: Part 2: Also, since the term bitrate is a relatively new term in my vocabulary, could you clarify what that forum member, in the passage that I quoted, meant when he said that this device creates MP4 files that are "bitrate-starved"? I know from software that allows you to rip audio CDs to create MP3 files that you can often specify the bitrate at which you want to rip those CDs, anywhere from 65kps (low-quality) up to 245kbps (high-quality), and I'm assuming, that in this case, "bitrate" is synonymous with the level of MP3 lossy compression. Is that correct?
Answers.UserDisplayName: Friedrich Bauer
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-04T05:18:59.280Z
Answers.Text: Part 3: If so, then when the forum member, in the passage that I quoted, claims that the compression artifacts that can be seen in the resulting video file are the result of the too-low bitrate that these devices use, does that mean that once the scanner has captured the information in a frame, when the scanner, finally, decides to encode that information as a video file using h.264, that the reason so many compression artifacts can be seen are the direct result of these devices using a higher-than-normal level of lossy compression, or, in other words, a low bitrate?
Answers.UserDisplayName: Friedrich Bauer
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-04T05:27:44.287Z
Answers.Text: Part 4: Is that what the term bitrate means, low bitrate=high level of compression, high bitrate=low level of compression? I'm just trying to understand what the term bitrate means. Correct me if I'm wrong but the information in the frames has been captured, it's just that a lot of that information is being thrown out because of lossy compression (low bitrate) in order to create a more-manageable file size, right?
Answers.UserDisplayName: Friedrich Bauer
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-04T06:23:02.953Z
Answers.Text: Yes exactly. High bitrate = less compression, so more of the original image is retained. You can still colour correct lossy images, but you will quickly start to see artefacts from the compression as soon as you adjust the colours even a small amount from the original. This is because the algorithms to reduce the image were throwing away much of the details that you are now trying to reintroduce when you adjust the image through colour correction.
Answers.UserDisplayName: tomh
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-04T08:50:09.887Z
Answers.Text: I think I got it. So, when that forum member wrote, "Yes you can make [the compression artifacts] look a little bit better but that does not fix the actual underlying problem: that detail was never captured by the wolverine in the first place--it's permanently lost," that's not entirely true. The information was captured, it's just that a lot of the information got thrown out because of the low bitrate setting.
Answers.UserDisplayName: Friedrich Bauer
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-05T05:58:13.867Z
Answers.Text: Last question and then I'll let you go. What do you think is the reason for the low bitrate encoding? According to the Amazon product listing page for the machine, the first [person](https://www.amazon.com/ask/questions/Tx15LE47VLK8CF4/ref=ask_dp_dpmw_al_hza) who answered this question about the machine suggested that it has to do with the speed at which the machine has to encode (20 fps). Is that a plausible explanation?
Answers.UserDisplayName: Friedrich Bauer
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-05T06:48:56.383Z
Answers.Text: Don’t know. Cost, I guess? Maybe simplicity for users who want small files as they’re easier to deal with.
Answers.UserDisplayName: tomh
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-09-01T16:57:06.877Z
Answers.LastActivityDate: 2021-09-01T16:57:06.877Z
Answers.UserDisplayName: tomh
Body: <p>I'm looking to digitize a couple of Super 8 film reels using what's called a <a href="https://rads.stackoverflow.com/amzn/click/com/B0785H3FGN" rel="nofollow noreferrer" rel="nofollow noreferrer">Wolverine</a> digitizer/converter, which is a device that allows a person to digitize Super 8 film. However, while researching what the reviews had to say, I stumbled upon this paragraph:</p>
  <blockquote>
  <p>[In regard to the image posted by <a href="https://8mmforum.film-tech.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=011395;p=12" rel="nofollow noreferrer">user</a> Laurent Bellier on 8mm Forum regarding the Wolverine device] Neat Video and other software plugins can help lessen the prominence
  of the compression artifacts. But they can never recover the detail
  lost to those artifacts in the first place. It's a garbage in-&gt;garbage
  out type situation. The problem with these machines is they produce
  mp4 files that are bitrate-starved. Compression artifacts are the
  result when there is too much detail for the capture settings to
  reproduce accurately. Yes you can make them look a little bit better
  but that does not fix the actual underlying problem: that detail was
  never captured by the wolverine in the first place--it's permanently
  lost.</p>
  </blockquote>
  <p>I'm already somewhat familiar with the concept of bitrate. Bitrate, if I understand correctly, is the amount of information from a video that is being shown on the screen per second. That is why it is generally better to watch a movie on Blu-ray rather than on Netflix because Netflix uses compression algorithms that are much more aggressive since internet speeds are a limiting factors. By watching the Blu-ray version, you are experiencing the movie at a higher &quot;fidelity,&quot; since it's being shown at a higher bitrate. In other words, the Blu-ray offers a &quot;truer&quot; version of the movie compared to the Netflix version.</p>
  <p>But what I don't understand is what bitrate has to do with MP4 compression artifacts.</p>
  <p>Also, what is meant by bitrate in the above case?</p>
  <p>The way the above paragraph uses the word &quot;bitrate,&quot; isn't bitrate the amount of information that is being captured per second from each frame <em>before</em> the video file is created <em>before</em> applying MP4 compression?</p>
  <p>If my understanding of the way the word bitrate is used in the above paragraph is correct, what does the person mean when the person says that the Wolverine device creates MP4 files that are &quot;bitrate-starved&quot;? Does the phrase &quot;bitrate-starved&quot; mean that the device is recording each frame <em>at a low bitrate</em>?</p>
  <p>If bitrate-starved means that the device is recording each frame at a low bitrate, what is the cause of this? Is a low bitrate caused by the machine scanning each frame too quickly, resulting in a low bitrate? Is a low bitrate caused by the light source not being bright enough to capture all of the information in each frame resulting in a low bitrate?</p>
  <p>And, finally, what do MP4 compression artifacts have to do with a low bitrate of an uncompressed video file? Does it have to do with there being too little information (low bitrate) in each frame? Is that what the person means by &quot;bitrate-starved&quot;?</p>
  <p>I really need help with this. I need to know the pros/cons of buying a consumer device vs. going with a professional service. The consumer device is cheaper but riskier as it uses the sprockets to move the film frame by frame, which can further damage old film.</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2021-09-04T06:27:25.830Z
Comments.Text: There’s also the issue of colour depth. A lot of consumer devices only use 8 bits of data to define the colour of each pixel. Some use less data to define red and blue pixels compared to green pixels as a way of reducing the amount of information that needs to be stored. This also reduces the ability to do image correction afterwards, regardless of overall bandwidth of the file.
Comments.UserDisplayName: tomh
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2021-09-04T08:44:47.453Z
Comments.Text: Yep, I'm already familiar with the concept of color depth. I have a scanner that I plan to use to scan a bunch of old family photographs. Assuming the device does not use less data for the red or blue pixels, 8 bits means 2^8 possible colors per channel. Since there are 3 channels that's 2^8*2^8*2^8 colors. But what I don't understand is that even if I could find a device that stored more than 8 bits per channel, wouldn't there be no way of even representing those added colors on a computer monitor? So, if your computer monitor can't show these colors, what's the point of scanning >8 bits?
Comments.UserDisplayName: Friedrich Bauer
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2021-09-04T08:48:07.243Z
Comments.Text: Because the image’s colour is defined with greater precision. So you as the grader get to decide what information is shown on screen and what is discarded when you grade your image. Eg you can pull more detail out of darker shadows if you need to make the image brighter, even though you couldn’t see that detail in the original ungraded image on your screen.
Comments.UserDisplayName: tomh
Tags: <digitisation>
Title: Why would MP4 compression show up as noise because of a low bitrate when digitizing a Super 8 film reel to digital?
UserDisplayName: Friedrich Bauer
ThreadText: # Why would MP4 compression show up as noise because of a low bitrate when digitizing a Super 8 film reel to digital?
  
  (Asked by: username_0 on 2021-08-31)
  
  I'm looking to digitize a couple of Super 8 film reels using what's called a [Wolverine](https://rads.stackoverflow.com/amzn/click/com/B0785H3FGN) digitizer/converter, which is a device that allows a person to digitize Super 8 film. However, while researching what the reviews had to say, I stumbled upon this paragraph:
  
  > [In regard to the image posted by [user](https://8mmforum.film-tech.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=1;t=011395;p=12) Laurent Bellier on 8mm Forum regarding the Wolverine device] Neat Video and other software plugins can help lessen the prominence
  > of the compression artifacts. But they can never recover the detail
  > lost to those artifacts in the first place. It's a garbage in->garbage
  > out type situation. The problem with these machines is they produce
  > mp4 files that are bitrate-starved. Compression artifacts are the
  > result when there is too much detail for the capture settings to
  > reproduce accurately. Yes you can make them look a little bit better
  > but that does not fix the actual underlying problem: that detail was
  > never captured by the wolverine in the first place--it's permanently
  > lost.
  
  I'm already somewhat familiar with the concept of bitrate. Bitrate, if I understand correctly, is the amount of information from a video that is being shown on the screen per second. That is why it is generally better to watch a movie on Blu-ray rather than on Netflix because Netflix uses compression algorithms that are much more aggressive since internet speeds are a limiting factors. By watching the Blu-ray version, you are experiencing the movie at a higher "fidelity," since it's being shown at a higher bitrate. In other words, the Blu-ray offers a "truer" version of the movie compared to the Netflix version.
  
  But what I don't understand is what bitrate has to do with MP4 compression artifacts.
  
  Also, what is meant by bitrate in the above case?
  
  The way the above paragraph uses the word "bitrate," isn't bitrate the amount of information that is being captured per second from each frame *before* the video file is created *before* applying MP4 compression?
  
  If my understanding of the way the word bitrate is used in the above paragraph is correct, what does the person mean when the person says that the Wolverine device creates MP4 files that are "bitrate-starved"? Does the phrase "bitrate-starved" mean that the device is recording each frame *at a low bitrate*?
  
  If bitrate-starved means that the device is recording each frame at a low bitrate, what is the cause of this? Is a low bitrate caused by the machine scanning each frame too quickly, resulting in a low bitrate? Is a low bitrate caused by the light source not being bright enough to capture all of the information in each frame resulting in a low bitrate?
  
  And, finally, what do MP4 compression artifacts have to do with a low bitrate of an uncompressed video file? Does it have to do with there being too little information (low bitrate) in each frame? Is that what the person means by "bitrate-starved"?
  
  I really need help with this. I need to know the pros/cons of buying a consumer device vs. going with a professional service. The consumer device is cheaper but riskier as it uses the sprockets to move the film frame by frame, which can further damage old film.
  
  **Tags:** digitisation
  
  > **Comments:**
  > **username_1**: There’s also the issue of colour depth. A lot of consumer devices only use 8 bits of data to define the colour of each pixel. Some use less data to define red and blue pixels compared to green pixels as a way of reducing the amount of information that needs to be stored. This also reduces the ability to do image correction afterwards, regardless of overall bandwidth of the file.  
  > **username_0**: Yep, I'm already familiar with the concept of color depth. I have a scanner that I plan to use to scan a bunch of old family photographs. Assuming the device does not use less data for the red or blue pixels, 8 bits means 2^8 possible colors per channel. Since there are 3 channels that's 2^8*2^8*2^8 colors. But what I don't understand is that even if I could find a device that stored more than 8 bits per channel, wouldn't there be no way of even representing those added colors on a computer monitor? So, if your computer monitor can't show these colors, what's the point of scanning >8 bits?  
  > **username_1**: Because the image’s colour is defined with greater precision. So you as the grader get to decide what information is shown on screen and what is discarded when you grade your image. Eg you can pull more detail out of darker shadows if you need to make the image brighter, even though you couldn’t see that detail in the original ungraded image on your screen.  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2021-09-01. Score: 2
  
  I don't own this scanner, but [looking at the specs](https://www.wolverinedata.com/assets/downloads/MovieMaker_PRO_V_3.0_Manual_.pdf), it appears to record in MJPEG mode, scanning one frame at a time.
  
  The MJPEG codec records each frame of video as a JPEG image. So each frame is compressed using JPEG, which is a lossy compression process.
  
  It then (I think?) has some software which can take the large MJPEG files and compress them further using mp4 h264? compression.
  
  MJPEG is a bit like a flick book of JPEG images - each one is compressed individually - there is no compression across multiple frames. This means it takes up more space than mpeg-4 compression which does analyse across frames, and so can compress videos further.
  
  With all lossy compression systems, the more detail there is an image, the harder it is to compress it efficiently. So if an image has lots of speckles and noise on it (like old film often does), this will either make the file much larger, or if the compressor is trying to target a given file size, the areas of low detail will become blocky.
  
  What *doesn't* tend to happen with video compression is added noise. By noise, I mean randomised pixels at different brightnesses or colours to the desired signal. Noise tends to be an analogue artefact (e.g. [grain in film](https://en.wikipedia.org/wiki/Film_grain) or [transmission noise](https://en.wikipedia.org/wiki/Noise_(video)) ("snow") in an analogue tv picture). Digital compression systems are terrible at compressing noisy images because every pixel is different (look at [this HBO logo](https://www.youtube.com/watch?v=P_Oh7HizY5I&ab_channel=bstore) as a good example).
  
  > **Comments:**
  > **username_0**: Thank you so much for answering, I wasn't sure anybody would. According to [this](https://forum.videohelp.com/threads/390464-Restoring-8mm-and-Super-8mm-transfers) user who bought the exact same scanner and had one of his MP4 files analyzed (its the 5th post down) using an automated service, the scanner uses the AVC codec aka h.264. However, according to the link of the user manual you posted, if you look on page 3 of the PDF, under features, it simply says that it encodes using "MPEG-4."  
  > **username_0**: When the manual says "MPEG-4," do they really mean h.264 given that h.264 is sometimes called MPEG-4 Part 10?  
  > **username_1**: Video files have wrappers and codecs. The .mp4 part of the file name refers to the wrapper. You can have many different codecs inside a video file- eg different ones for audio and video tracks. But mp4 files most commonly use h264 as the codec.  
  > **username_1**: A lot of other things will affect the quality of the transfer, not least the optical quality of the signal path - eg the size and quality of the lens and the sensor. The bandwidth limitation of how the files are encoded will also affect the quality. Without having one to play with it’s tricky to offer any more advice.  
  > **username_0**: Help me understand your 4th paragraph. I thought MJPEG and MPEG-4 were two opposing compression standards, and so it wouldn't be advisable to use them both together, but the scanner's manual clearly states that the machine uses MPEG-4, with no mention of MJPEG, and in your reply you state that the scanner uses MJPEG, so which is it? Are you saying that this particular scanner uses both MJPEG _and_ MPEG-4 compression together?  
  > **username_1**: I may be wrong about that - initially I thought I saw MJPEG mentioned on the amazon page, but looking now I can only see mp4 mentioned  
  > **username_0**: I just have a few more questions. Correct me if I'm wrong, but assuming this device encodes video using h.264, isn't h.264 mainly a delivery codec, rather than a codec meant to allow for editing in post? For instance, I already know this device doesn't allow you to turn off auto-white balance, although it does allow you to adjust exposure somewhat, so if I ever wanted to adjust the white balance in post, wouldn't the use of this codec make it hard to adjust things like white balance, exposure, or even do any kind of color correction without the whole process being destructive to the MP4 file?  
  > **username_1**: Yes you are right. It’s definitely not designed for use by editors or anyone who wants to manipulate footage afterwards.  
  > **username_0**: Part 1: OK, h.264 is not a codec designed for editing, but if the scanner gets the auto-white balance wrong, is it even worth trying to edit the files in post, or do you consider it a hopeless endeavor?  
  > **username_0**: Part 2: Also, since the term bitrate is a relatively new term in my vocabulary, could you clarify what that forum member, in the passage that I quoted, meant when he said that this device creates MP4 files that are "bitrate-starved"? I know from software that allows you to rip audio CDs to create MP3 files that you can often specify the bitrate at which you want to rip those CDs, anywhere from 65kps (low-quality) up to 245kbps (high-quality), and I'm assuming, that in this case, "bitrate" is synonymous with the level of MP3 lossy compression. Is that correct?  
  > **username_0**: Part 3: If so, then when the forum member, in the passage that I quoted, claims that the compression artifacts that can be seen in the resulting video file are the result of the too-low bitrate that these devices use, does that mean that once the scanner has captured the information in a frame, when the scanner, finally, decides to encode that information as a video file using h.264, that the reason so many compression artifacts can be seen are the direct result of these devices using a higher-than-normal level of lossy compression, or, in other words, a low bitrate?  
  > **username_0**: Part 4: Is that what the term bitrate means, low bitrate=high level of compression, high bitrate=low level of compression? I'm just trying to understand what the term bitrate means. Correct me if I'm wrong but the information in the frames has been captured, it's just that a lot of that information is being thrown out because of lossy compression (low bitrate) in order to create a more-manageable file size, right?  
  > **username_1**: Yes exactly. High bitrate = less compression, so more of the original image is retained. You can still colour correct lossy images, but you will quickly start to see artefacts from the compression as soon as you adjust the colours even a small amount from the original. This is because the algorithms to reduce the image were throwing away much of the details that you are now trying to reintroduce when you adjust the image through colour correction.  
  > **username_0**: I think I got it. So, when that forum member wrote, "Yes you can make [the compression artifacts] look a little bit better but that does not fix the actual underlying problem: that detail was never captured by the wolverine in the first place--it's permanently lost," that's not entirely true. The information was captured, it's just that a lot of the information got thrown out because of the low bitrate setting.  
  > **username_0**: Last question and then I'll let you go. What do you think is the reason for the low bitrate encoding? According to the Amazon product listing page for the machine, the first [person](https://www.amazon.com/ask/questions/Tx15LE47VLK8CF4/ref=ask_dp_dpmw_al_hza) who answered this question about the machine suggested that it has to do with the speed at which the machine has to encode (20 fps). Is that a plausible explanation?  
  > **username_1**: Don’t know. Cost, I guess? Maybe simplicity for users who want small files as they’re easier to deal with.  
  
  ---
  
  