[FFmpeg-cvslog] Support decoding yuv442 and yuv421 jpeg images.
Carl Eugen Hoyos
git at videolan.org
Tue Dec 27 18:32:46 CET 2011
ffmpeg | branch: master | Carl Eugen Hoyos <cehoyos at ag.or.at> | Tue Dec 27 18:21:38 2011 +0100| [387d86077f5237e53cec7a4ed31f5531224feebf] | committer: Carl Eugen Hoyos
Support decoding yuv442 and yuv421 jpeg images.
Fixes ticket #787.
> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=387d86077f5237e53cec7a4ed31f5531224feebf
---
libavcodec/mjpegdec.c | 28 ++++++++++++++++++++++++++++
libavcodec/mjpegdec.h | 2 ++
2 files changed, 30 insertions(+), 0 deletions(-)
diff --git a/libavcodec/mjpegdec.c b/libavcodec/mjpegdec.c
index e082147..19438ce 100644
--- a/libavcodec/mjpegdec.c
+++ b/libavcodec/mjpegdec.c
@@ -337,12 +337,19 @@ int ff_mjpeg_decode_sof(MJpegDecodeContext *s)
}
assert(s->nb_components==3);
break;
+ case 0x12121100:
+ s->avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV444P : PIX_FMT_YUVJ444P;
+ s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
+ s->yuv442 = 1;
+ break;
case 0x11000000:
s->avctx->pix_fmt = PIX_FMT_GRAY8;
break;
case 0x12111100:
+ case 0x22211100:
s->avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV440P : PIX_FMT_YUVJ440P;
s->avctx->color_range = s->cs_itu601 ? AVCOL_RANGE_MPEG : AVCOL_RANGE_JPEG;
+ s->yuv421 = pix_fmt_id == 0x22211100;
break;
case 0x21111100:
s->avctx->pix_fmt = s->cs_itu601 ? PIX_FMT_YUV422P : PIX_FMT_YUVJ422P;
@@ -1091,6 +1098,27 @@ int ff_mjpeg_decode_sos(MJpegDecodeContext *s,
return -1;
}
}
+ if (s->yuv421) {
+ uint8_t *line = s->picture_ptr->data[2];
+ for (i = 0; i < s->height / 2; i++) {
+ for (index = s->width - 1; index; index--)
+ line[index] = (line[index / 2] + line[(index + 1) / 2]) >> 1;
+ line += s->linesize[2];
+ }
+ } else if (s->yuv442) {
+ uint8_t *dst = &((uint8_t *)s->picture_ptr->data[2])[(s->height - 1) * s->linesize[2]];
+ for (i = s->height - 1; i; i--) {
+ uint8_t *src1 = &((uint8_t *)s->picture_ptr->data[2])[i / 2 * s->linesize[2]];
+ uint8_t *src2 = &((uint8_t *)s->picture_ptr->data[2])[(i + 1) / 2 * s->linesize[2]];
+ if (src1 == src2) {
+ memcpy(dst, src1, s->width);
+ } else {
+ for (index = 0; index < s->width; index++)
+ dst[index] = (src1[index] + src2[index]) >> 1;
+ }
+ dst -= s->linesize[2];
+ }
+ }
emms_c();
return 0;
out_of_range:
diff --git a/libavcodec/mjpegdec.h b/libavcodec/mjpegdec.h
index d88ba7b..23bc077 100644
--- a/libavcodec/mjpegdec.h
+++ b/libavcodec/mjpegdec.h
@@ -58,6 +58,8 @@ typedef struct MJpegDecodeContext {
int ls;
int progressive;
int rgb;
+ int yuv421;
+ int yuv442;
int rct; /* standard rct */
int pegasus_rct; /* pegasus reversible colorspace transform */
int bits; /* bits per component */
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