re xv problems in article apr nessie mcc ac uk c c lilley mcc ac uk writes in article rohjc avt cc tut fi jk lehtori cc tut fi kouhia juhana writes i wrote something about making color modifications quickly with bit quantized images and only at the saving the image to file process we have to make the modifications to the bit image this makes sense because the main use of xv is only viewing images doing many changes to image we should keep all modifications in a buffer and then before making the operations to bit image we should simplify the operation list for unnecessary operations think about what you are saying here the bit image is quantised down to bits so many similar colours are mapped onto a single palette colour this colour gets modified in fairly arbitrary ways you then want to apply these modifications back to the bit file so you have to find which colours mapped to this one palette colour i suppose you don t know what about we have discussed we discussed about error s in xv which shows images only as bit and my suggestion above works perfectly with it so far i have seen a colormap editing window in xv that is there must be a colormap anyway the problems you present are exist anyway and i didn t tried to solve them at all because i would not make such problems to my programs in the first place gamma and color corrections are easily done to bit image as i presented there s no need make tricks from bit quantized image back to bit image how would you suggest doing colour editing on a bit file how would you group related colours to edit them together only global changes could be done unless the software were very different and much more complicated ok you re writing about situation that user want edit images as bit and user want edit individual colors your questions by the way jumps off the discussion a bit my solution doesn t work because there s no colormap withing real bit image you see user see bit image going back to bit is silly about changing individual colors in bit quantized rasterized image changing individual colors in colormap is useless in most cases if the image is quantized and rasterized small change may make serious errors to anywhere in the image xv allows this feature but i don t recommend to use it with the mentioned type images moreover xv is not a paint program you can only make those global changes in full bit xv changing individual colors sounds like paint program job if person have bit screen there s need for tricks to get the original bit image modified because user don t see full bit image there s need to make approximations and it is not possible to modify individual colors but individual pixels or pixel groups if image is rasterized to select indiavidual color there could be x cursor window which shows true color image in cursor window area selecting individual color is possible from that ok i don t have thought very much bit painting programs never seen such in good view and are not planned to make such not to mention bit painting program in bit screen yes again what is was wrong with xv it saved bit quantized rasterized images as bit jpegs jpeg is not designed for that also human expect that bit will be saved as bit image say person would like to crop part of the image and save it then it is expected that the image still is the same so xv were designed without thinking about human interface and how human expect the program work design error i have heard xv were designed first for bit images files but it were not good idea to take full bit images without making major change to the original design so even all screen images are bit the processed images and saved images could have been bit very easily instead of bit before anybody will make a note yes i may as well make a lift where up means that the lift goes down and down means that the lift goes up and put a note on this design solution to the manuals however even the manuals tells the correct situation it doesn t solve the problem americans the lift is just an example well my text may be a bit hard reading hopefully you suggeeded to read it juhana kouhia
