On Fri, Aug 09, 2019 at 07:29:46PM +0300, Nick Renieris wrote: > From: Nick Renieris <velocit...@gmail.com> > > Main image data in DNGs is usually comprised of tiles, each of which is a > Huffman-encoded lossless JPEG. > > Tested for ljpeg regressions with: > `ffmpeg -f lavfi -i testsrc=d=1 -vcodec ljpeg test.avi` > `ffmpeg test.avi out.avi` > The modified code in ljpeg_decode_rgb_scan runs without issues. > > Signed-off-by: Nick Renieris <velocit...@gmail.com> > --- > libavcodec/mjpegdec.c | 52 +++++++++++++++++++++++++++++++++++++------ > libavcodec/mjpegdec.h | 1 + > 2 files changed, 46 insertions(+), 7 deletions(-) [...]
> @@ -1102,12 +1128,19 @@ static int ljpeg_decode_rgb_scan(MJpegDecodeContext
> *s, int nb_components, int p
> topleft[i] = top[i];
> top[i] = buffer[mb_x][i];
>
> - PREDICT(pred, topleft[i], top[i], left[i],
> modified_predictor);
> -
> dc = mjpeg_decode_dc(s, s->dc_index[i]);
> if(dc == 0xFFFFF)
> return -1;
>
> + if (!s->bayer || mb_x) {
> + pred = left[i];
> + } else { /* This path runs only for the first line in bayer
> images */
> + vpred[i] += dc;
> + pred = vpred[i] - dc;
> + }
> +
> + PREDICT(pred, topleft[i], top[i], pred, modified_predictor);
> +
> left[i] = buffer[mb_x][i] =
> mask & (pred + (unsigned)(dc * (1 << point_transform)));
> }
This should be done outside the width*height sample loop
The special handling of the left pixel for other ljpeg is also done
outside that loop
[...]
--
Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB
What does censorship reveal? It reveals fear. -- Julian Assange
signature.asc
Description: PGP signature
_______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
