I have cached preview files from Capture One (a photo processing program, similar to Lightroom) where I have lost the originals. Capture One saves previews in their proprietary .cop format and I'm not sure how to go about identifying what's what in there.
There are the strings ETIFFTagInteropIFD and JPEG Embedded TIFF Tags seen in the HEX view which suggests that they are somehow embedding a TIFF in there.
I do have original JPEG files with their corresponding COP-file, but when comparing them there isn't much that's similar - which makes sense I guess, since the preview COP-file is roughly half the size of the original.
What conclusions can I draw from this and what are some good tools for going further?
Related
Anyone knows why the image, shown below, is partially gray while loading? I assume it has something to do with progressive JPG, but I haven't seen the grayscale effect before. Is there some kind of a JPG export setting that enables that? How is it called? Can I disable it?
Direct image link
Edit:
The problem could either be the problem described in #KonradDzwinel answer OR my answer, both could look identical:
What is the problem
For some reason the file is saved or produced in way that make the file we call it Lossless JPEG.
I am not sure which software, tool or how this problem is was produced, but that won’t change the fact that your file had have some issues or even corrupted.
How to find the problem in the file
Your file was saved in way that it works identical but it had issues. To check whether your file is healthy or not, it requires a tool to scan/analysis the image file. I use a very nice and easy to use tool (software) called JPEGsnoop (link for download). This tool is free and I used it to scan and analysis your image files for problems.
Your file comes up with few places with following note, (the screen-shot btw shows only one note, but there were more):
NOTE: Scan parsing doesn’t support this SOF mode.
After I have re-saved the file correctly and analysis it again, it does not show any problems or notes:
What I did to create a problem FREE image file
For testing I have used Photoshop 5.5 to open the Lossless file and save it with new name with default jpeg (since I don't have the original file). But correctly I assume you have the original file, and I assume you have Photoshop any version does not matter OR any other image tool. Try to optimize your jpeg file best possible, analysis it and remember/note the saving setting for future wise image saving.
Here is an example of my Photoshop save settings, which result in problem FREE file:
How can I learn more about Lossless JPEG
I won’t go in details of this problem but I will leave some link that explain it in details, I hope also you find this is useful to solve your issue:
http://www.impulseadventure.com/photo/fix-corrupt-jpeg-photo.html
http://fileformats.archiveteam.org/wiki/JPEG
http://fileformats.archiveteam.org/wiki/Lossless_JPEG_%28original%29
http://www.howtogeek.com/142174/what-lossless-file-formats-are-why-you-shouldnt-convert-lossy-to-lossless/
Software JPEGsnoop
http://www.impulseadventure.com/photo/jpeg-snoop.html
Progressively encoded JPEGs contain ten scan layers by default. That means ten iterative layers of image information build on each other to deliver the final visual quality of the image. The first visible scan layer of a progressive JPEG is always highly pixelated and often black & white because it saves on color channel information.
Source (emphasis mine)
Another resource that explores this issue in lengh: http://cloudinary.com/blog/progressive_jpegs_and_green_martians
Since Adobe has declared Fireworks dead, it is apparent that many of us are potentially locked into Fireworks in terms of the proprietary layered PNG format that they have used. I have been hunting for options to extract / convert my documents over to either PSD's or some other layered SVG structure (perhaps similar to what Sketch does on OS X).
Anyone have any ideas for extracting the contents of Fireworks' PNGs programmatically? So far I haven't seen any libraries to make this feasible and really no discussion of how the metadata is structured in a Fireworks PNG in a format that would help to reverse engineer this format for proper conversion and extraction.
I am developing a game in j2me. How to handle images in .dat format.
I downloaded some games and extracted jar , found some dat format images and not able to open that images and images size also very less.. what tools I need to use?
Ref link
enter link description here
Not able to find solution?
A dat file could be anything. Depends what the developer felt like doing.
Some developers chose to strip PNG files of their header, and added the header back in the code. This was partly done in order to save a few bytes (because they mattered back then), and partly because of the challenge in doing it like that, and partly because it ensured all images used the exact same palette.
So that's one possibility, but it really could be anything.
As stated by mr_lou, there really isn't anything special about a .dat extension.
The steps to re-compile a file usually start with opening the file up in a hex editor and then looking at the first bits of information in the file. You then basically work from there to re-compile the data necessary for a 'normal' program to interpret the file. In particular, the first 8-16 bytes are often very helpful for determining what type of file it is "supposed" to be.
If you are looking at a png file (that's what I usually prefer to use for art assets) then you can reference http://en.wikipedia.org/wiki/Portable_Network_Graphics to see how a 'normal' png might look. When you're tweaking to save bytes you often strip unnecessary fields from png headers (things like the ancillary chunks) and using a common palette.
However, remember that it's not necessarily image data. It could be things like level data, sound, default stats or any particular amount of stuff.
Is there a direct and fast way to convert XPS (XML Paper Specification) files to SVG format?
I can convert XPS to PDF and then using inkscape to convert them to SVG.
But the PDF->SVG step is very time consuming though this process seems is not CPU consuming.
My understanding is that be cause XPS is a vector based format, converting it to another vector based format like SVG must be feasible and much faster than converting raster based format (though i'm not entirely sure pdf is just raster base) to vector based formats.
BTW, the goal is to display vector based images in browser, and I've XPS files.
libgxps reads XPS and can create SVG files.
I tried it on Cygwin with the xpstosvg command and worked fine.
I tried xpstosvg from the answer above to convert an XPS document with about 100 pages. Unfortunately, the tool produced only one large SVG image with about 90 MB file size, which was not exactly what I was looking for, since the file could not be viewed and I needed one image per page.
Also the manual of the program did not give any hint how to get one image per page. In the end I used an online XPS converter, which really created a SVG image for each page.
I'm working with C# and a usb webcam that supports YUY2 or MJPG image formats. Thus far I've always had it in YUY2 mode and that works fine. Recently I tried changing the format to MJPG thinking that it would then feed my program one JPEG image per frame capture. It appears to almost do that. When I try to display the buffer, my app always takes an exception which is vague, but seems to indicate that the stream is invalid. I then copied one of the buffers to a file and tried to view it with IrfanView and it tells me that there is no huffman table. Looking at the buffer with a binary editor, I see it does have the SOI and EOF JPEG markers (and several others); however, it doesn't contain a huffman table marker. Any ideas what I'm doing wrong here? I've read a bit about JPEG and apparently there are cases where images can use a standard huffman table to reduce file size; however, if that's the case, how do I insert this into the image (if appropriate)?
This is with reference to Microsoft Lifecam by the way.
Part of the Motion-JPEG standard for AVI files is that a fixed Huffman table will be used so that it doesn't have to be stored in every frame.