From: Nick Renieris <velocit...@gmail.com>
Signed-off-by: Nick Renieris <velocit...@gmail.com>
---
libavcodec/mjpegdec.c | 35 ++++++++++++++++++++++++-----------
1 file changed, 24 insertions(+), 11 deletions(-)
diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
index 6391107f78..94cf73549d 100644
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@ -412,13 +412,21 @@ int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
return AVERROR_PATCHWELCOME;
}
- /* Lossless JPEGs encoded in DNGs are commonly bayer-encoded. They contain
2
- interleaved components and the width stored in their SOF3 markers is the
- width of each one. We only output a single component, therefore we need
- to adjust the output image width. */
- if (s->lossless == 1 && nb_components == 2) {
- s->bayer = 1;
- width *= 2;
+ /* Lossless JPEGs encoded in DNGs are commonly bayer-encoded. */
+ if (s->lossless) {
+ if (nb_components == 1) {
+ /* They can contain 1 component, which is double the width and
half the height
+ of the final image (rows are interleaved). We don't handle the
decoding in
+ this file, but leave that to the DNG decoder. */
+ s->bayer = 1;
+ } else if (nb_components == 2) {
+ /* Or they can contain 2 interleaved components and the width
stored in their
+ SOF3 markers is the width of each one. We only output a single
component,
+ therefore we need to adjust the output image width. We handle
the
+ deinterleaving (but not the debayering) in this file. */
+ s->bayer = 1;
+ width *= 2;
+ }
}
/* if different size, realloc/alloc picture */
@@ -1184,10 +1192,15 @@ static int ljpeg_decode_rgb_scan(MJpegDecodeContext *s,
int nb_components, int p
ptr[3*mb_x + 0] = buffer[mb_x][1] + ptr[3*mb_x + 1];
ptr[3*mb_x + 2] = buffer[mb_x][2] + ptr[3*mb_x + 1];
}
- } else if (s->bayer && nb_components == 2) {
- for (mb_x = 0; mb_x < width; mb_x++) {
- ((uint16_t*)ptr)[2*mb_x + 0] = buffer[mb_x][0];
- ((uint16_t*)ptr)[2*mb_x + 1] = buffer[mb_x][1];
+ } else if (s->bayer) {
+ if (nb_components == 1) {
+ for (mb_x = 0; mb_x < width; mb_x++)
+ ((uint16_t*)ptr)[mb_x] = buffer[mb_x][0];
+ } else if (nb_components == 2) {
+ for (mb_x = 0; mb_x < width; mb_x++) {
+ ((uint16_t*)ptr)[2*mb_x + 0] = buffer[mb_x][0];
+ ((uint16_t*)ptr)[2*mb_x + 1] = buffer[mb_x][1];
+ }
}
} else {
for(i=0; i<nb_components; i++) {
--
2.21.0.windows.1
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