Added support for RLE compressed images. This patch makes the player almost complete allowing to read all type 1,2 and 3 RAS files. Only types 4 and 5 are missing which are images converted from TIFF and IFF.
As a base I used the reference implementation found on the official site at https://qoiformat.org/ (MIT license).
I added a class to convert scan lines in scanlineconverter.cpp. The class takes advantage of the QImage conversion and contrary to what one might expect, with large images it improves performance (compared to converting the whole image) 😄
In progressive mode, for each line, the following conversions (only if needed) are made before saving:
1. If the icc profile is set, the line is converted to sRGB or sRGB Linear.
2. The line is scaled to 8 bits with RGBA order.
- Progressive load from file
- Added support for 1-bit image
- Images with palette are now Index (instead of RGB32)
- Added options support (Size, Format)
- Added some test cases
- Improved performance by directly accessing the scanline
- Support for more RAS extension (taken from GIMP)
The code should works "as is" also on KF5.
- Support for images with transparency
- Precise colorspace conversion using QT color spaces
- Set the correct resolution
- Set useful metadata
- Support for RGBX16FPx4 format in Qt 6
- Speed improvements

This is a patch over MR !108 by @sandsmark. Martin has done a great job implementing support and I find it a shame not to use it.
I made sure that the results are the same as the current version and fixed the problems of pixels with wrong colors with color depth grater than 8 bits. I also fixed conversion errors on mask and gray images (16/32 bits).
Unfortunately the internal rendering engine of the original code is 8-bit so I always forced the output of 8-bit images to correct the problems (see image below). Since it is a plugin with a "rendering engine", the tests to seriously validate it are potentially endless (as the original version is not perfect).
Errors of the original version of the MR (right) which should no longer occur:

- fix buffer overflow with corrupted images without image data
- fix unable to read very small images (e.g. 1x1 px)
- new test cases added
- detect incomplete files by checking the end of streams as written in the specs
- 1-bit writer: checks where is black and use NOT operator only if needed
- Fix images with witdh == 65536(*)
- Checks result of disk writes and reads on all formats
(*) PCX formats support images with with of 65536 but only if the header field bytesPerLine is valid (no overflow). This means that the width 65536 is supported on 1bpp images only.
The previous version of the plugins wrote an image with width of 65536px in the wrong way and it was unable to read it (wrong image returned). I verified that Photoshop and Gimp weren't able to read the image either.
- Fix wrong RGB channel order if image format is other than (A)RGB32
- Write right resolution
- Set right resolution on image load
- Return false on write error
- Save images with depth greater than 24-bits
PSD files are saved with as alpha premultiplied. The problem is that alpha refers to white instead of black so it requires transformation formulas. Then, to conver PS premultiplied to QImage premultiplied you have to use the following formula:
* V = Alpha + Vps - Max (C, M, Y, K, R, G, B, Gray, L\* components)
* V = Vps + (Alpha - Max + 1) / 2 (a\*, b\* components)
Where Max is the maximum value depending on the image depth and Vps is the valued read from the file.
Plugin to read RAW camera images based on LibRAW.
- Supersedes MR !86
- Support to LibRaw 0.20 and 0.21-Beta
- Support to multi-shot images: use imageCount(), jumpToImage() to select the wanted shot
- By default generates 16-bits sRGB images using camera white balance and interpolation AHD
- Should fix CCBUG: 454208: on my Debian with KF5.96 and the pulgin installed, I see the preview of all my RAW files (ARW included) in Dolphin
News compared to V1 (MR !86)
- Fix possible stack overflow due to the huge size of LibRaw class
- Fix image allocation with Qt 6 (make use of QImageIOHandler::allocateImage())
- Support to XMP metapacket
- Support to quality option. For e.g. you can focus on quality (q = 10) or speed (q = 1)
- oss-fuzz available [here](https://github.com/mircomir/oss-fuzz/tree/raw_fuzz/projects/kimageformats)
- Fix parasite "gimp-comment" not set due to null QImage
- Support to parasite "icc-profile" using Qt 5.14+ API
- Added parasite "gimp-image-metadata" as QImage metadata "XML:org.gimp.xml"
- Added a XCF with XML metadata and icc prifile embedded in autotest folder (generated by GIMP 2.10.30)
- Tested with Qt 5.15.2 and Qt 6.2.3 under Windows and Qt 6.2.3 under macOS
Unfortunately none of them pass since it seems they can't load a png,
save it to their format with loseless quality and read it back and get
exactly the same contents than the png
The HDR QImageIOHandler plugin only supports the default image orientation (-Y +X) in .hdr files. It mixes up the width and height however, resulting in non-square images not loading.
This fix adds a check for the standard image orientation in the file and returns false (with error message) if that fails.
If it succeeds, it takes the height from the -Y component, and the width from the +X component, resulting in successful loading of the image.
Add autotest images for landscape and portrait HDR (Radiance RGBE) loader
BUGS: 433877