Darktable unable to process DNG from Panasonic LX1

darix · June 20, 2018, 10:53pm

is this in DT master already?

LebedevRI · June 21, 2018, 6:23am

github.com/darktable-org/darktable

RawSpeed submodule update: LJpegDecompressor: support degenerate raws with width % 2 != 0

committed 02:13PM - 20 Jun 18 UTC

LebedevRI

+1 -1

This is needed e.g for DNG's converted from Panasonic DMC-LX1 raws. I have no w…ords. What were they (Adobe) thinking. They discard padding columns, that were garbage, and end up with such an odd raw, where the tiles (LJPEG-compressed) still have padding, yet the DNG image sizes specify that it has to be discarded. What is even worse, the image width is not multiple of two, and the LJPEG's components-per-pixel is 2, so we have to very-special-handle this case, to not completely discard that last required block (then we'd be producing nondeterministic garbage in those last few columns), but also not fully decode it, because we don't have anywhere to write it, We could, of course, introduce something like "internal padding columnts", in fact we already pad the rows to be 16-byte aligned, but that padding is used for ASAN overflow detection. So right now i'm not seeing any more reasonable fix. :/ Fixes #12239

darix · June 21, 2018, 11:09am

So @Luemmel can test with our master snapshot packages

Luemmel · June 21, 2018, 11:53am

I would love to do so, @darix, but the snapshots are Linux only, aren’t they? I’m on Windows, I thus will have to wait until next release, I guess.

Luemmel · June 21, 2018, 2:07pm

Just set up a virtual machine with Ubuntu and tried the snapshot: Works great! Thank you, @LebedevRI und @darix. Can’t wait for the Windows build.