![]() My extracted color matrices are equal in every digit to the dcraw matrices. Should LibRaw store all (possibly copyrighted) Adobe color data in source code? I don't think so. > * The 'DNG processing model' (quoting from Adobe staff member in dpreview forums) introduced in DNG 1.2 is much more complex, than in DNG 1.0/1.1. Until now all open source raw converters are based on dcraw and I think it's wrong to use only one matrix just because dcraw doesn't implement the full DNG standard. ![]() You can only know about open source raw converters. If you already use Adobe programs, you can also use free Adobe DNG converter. > * the only programs that needs/uses two color matrices in DNG file are Adobe programs (Lightroom and Camera Raw). I've added cam_xyz field to LibRaw interface only because it was a very small step (2 lines of code and 5 lines in documentation). In my thoughts, the only place to store DNG-related color data is in DNG converter itself. We (LibRaw team) dislike 'DNG processing model' because of very poor image quality produced by Adobe products (try compare with Raw Photo Processor): high noise levels (produced by mixing low noise Green with high noise Red channels), false colors (produced by using ProPhoto as internal space) and poor quality of color profiles (produced by small gamut of color targed used). * The 'DNG processing model' (quoting from Adobe staff member in dpreview forums) introduced in DNG 1.2 is much more complex, than in DNG 1.0/1.1. * the only programs that needs/uses two color matrices in DNG file are Adobe programs (Lightroom and Camera Raw). In this case we rely on Coffin's copyright clearance and free status of dcraw itself. LibRaw already have one set of DNG ColorMatrix tables derived from dcraw code. LibRaw will not store _additional_ DNG-related data due to three reasons: It will be fine to use the same file format. xml is the right way to store these values. I hope that Adobe will publish a future version using a real open source license such as BSD (ie, in the same way as the XMP SDK is published). To conclude: DNG SDK is not perfect, but not too bad. The plan for the future is to improve the DNG tags creation following special makernotes entries, to support new RAW file formats, and to add a new option to backup the original RAW file within the DNG. The generated is a valid DNG file, which is checked by Adobe DNGValidate tool. The tool transfers RAW data to DNG, creates a JPEG preview and a thumbnail, sets a lots of TIFF-EP/DNG tags with original raw files metadata, does a backup of all Exif metadata and makernotes, and creates a set of XMP tags, accordingly. See below for a screenshot of this tool in action. After a lots of conversions tests using official Adobe DNG converter and my program, a new kipi-plugin is born. I would like to Alex Tutubalin from LibRaw for pointing this out.Īfter few weeks of studying the DNG SDK code to learn the API and the code from this little application dedicated to convert Canon Powershoot RAW files to DNG, I have finally found the way to write the first RAW to DNG converter for Linux, which support a lots of major RAW camera formats, as NEF, CR2, MRW, PAF, etc.Ī DNG codec has been written around the DNG SDK and a command line tool to perform unit-tests. By chance, after the port of libkdcraw to LibRaw, I have found an easy way to extract these data, plus lots of relevant meta-information, fully suitable for the DNG SDK. My first problem with DNG is to be able to extract un-demosaiced RAW image data to pass to DNG sdk. ![]() But after having found this nice web site from Barry Pearson which provides a huge collection of papers about DNG, I had a second look at the DNG SDK. My first viewpoint about DNG SDK from Adobe has been wrong: missing tutorials, weird API documentation, wrong source code licence, etc. I have already talked about DNG in another ticket. Why should one support DNG under Linux? To improve interoperability with other photo-management programs such as Adobe tools, and to improve Digital Asset Management (DAM), as Gerhard Kulzer discusses in this nice tutorial and in particular in Part 2. For a long time, many people asked me to implement a RAW camera image converter to Digital NeGative (DNG). ![]()
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