[FFmpeg-devel] [PATCH] libopenjpeg: support decoding with bits per pixel greater than 8
Jean First
jeanfirst at gmail.com
Thu Dec 22 22:26:21 CET 2011
> lets see what the code path would be for PIX_FMT_RGB24
> in check_image_attributes
> the compRatio should be anything but 0111111/0112121/0112222, which means
> non-equal component size rgb24 (haven't heard of one yet)
>
> or if it's equal component size - precision is checked to be 8 to return
> rgb24:
> switch (c0.prec) {
> case 8: return PIX_FMT_RGB24;
>
> i'm fine with applying the patch, there's nothing wrong with it, but to me
> it's a bit of premature optimization.
> isnt it mostly a matter of taste?
> to my taste i'd just wait to see if someone finds an example where error is
> triggered.
>
> On Thu, Dec 22, 2011 at 10:27 AM, Jean First <jeanfirst at gmail.com> wrote:
>
> > On Wed Dec 21 21:26:45 2011, Alex Zhukov wrote:
> >
> >> from the top of my head: copyto8 expects the 8bit precision therefore no
> >> ">>adjust" should be needed
> >> can you provide an example video where this is not the case?
> >>
> >> On Wed, Dec 21, 2011 at 5:33 AM, Jean First<jeanfirst at gmail.com> wrote:
> >>
> >> Hi,
> >>>
> >>> attached patch fixes a regression introduced with commit eb511ef6.
> >>> maybe libopenjpeg_copyto8 and libopenjpeg_copyto16 need this fix too.
> >>> Alex Zhukov, can you please check this ?
> >>>
> >>> Jean
> >>>
> >>> ---
> >>>
> >>
> > Hi Alex,
> > No atm not. I suggest to apply the patch until we have a sample that
> > triggers the error.
> > Jean
Well it's not an optimisation - it is a fix for a regression. We might wait
a long time for that sample - in the meantime this is fixed.
I added PIX_FMT_48 decoding, although the conversion from <16 bit to 16 bit
might not be the best solution. Everything above 8 bit will be treated as
16 bit.
And should I start top posting - or will you start bottom posting ;)
Jean
---
libavcodec/libopenjpegdec.c | 32 +++++++++++++++++++++++++++++++-
1 files changed, 31 insertions(+), 1 deletions(-)
diff --git a/libavcodec/libopenjpegdec.c b/libavcodec/libopenjpegdec.c
index baa516b..1f904da 100644
--- a/libavcodec/libopenjpegdec.c
+++ b/libavcodec/libopenjpegdec.c
@@ -54,7 +54,7 @@ static enum PixelFormat check_image_attributes(AVCodecContext *avctx, opj_image_
case 0111111: goto libopenjpeg_yuv444_rgb;
case 0112121: goto libopenjpeg_yuv422;
case 0112222: goto libopenjpeg_yuv420;
- default: return PIX_FMT_RGB24;
+ default: goto libopenjpeg_rgb;
}
libopenjpeg_yuv420:
@@ -80,6 +80,13 @@ libopenjpeg_yuv444_rgb:
case 10: return PIX_FMT_YUV444P10;
case 16: return PIX_FMT_YUV444P16;
}
+
+libopenjpeg_rgb:
+ switch (c0.prec) {
+ case 8: return PIX_FMT_RGB24;
+ default: return PIX_FMT_RGB48;
+ }
+
return PIX_FMT_RGB24;
}
@@ -107,6 +114,24 @@ static inline void libopenjpeg_copy_to_packed8(AVFrame *picture, opj_image_t *im
}
}
+static inline void libopenjpeg_copy_to_packed16(AVFrame *picture, opj_image_t *image) {
+ uint16_t *img_ptr;
+ int index, x, y, c;
+ int adjust[4];
+ for (x = 0; x < image->numcomps; x++) {
+ adjust[x] = FFMAX(FFMIN(16 - image->comps[x].prec, 8), 0);
+ }
+ for (y = 0; y < picture->height; y++) {
+ index = y*picture->width;
+ img_ptr = (uint16_t*) (picture->data[0] + y*picture->linesize[0]);
+ for (x = 0; x < picture->width; x++, index++) {
+ for (c = 0; c < image->numcomps; c++) {
+ *img_ptr++ = image->comps[c].data[index] << adjust[c];
+ }
+ }
+ }
+}
+
static inline void libopenjpeg_copyto8(AVFrame *picture, opj_image_t *image) {
int *comp_data;
uint8_t *img_ptr;
@@ -277,6 +302,11 @@ static int libopenjpeg_decode_frame(AVCodecContext *avctx,
libopenjpeg_copy_to_packed8(picture, image);
}
break;
+ case 6:
+ if (ispacked) {
+ libopenjpeg_copy_to_packed16(picture, image);
+ }
+ break;
default:
av_log(avctx, AV_LOG_ERROR, "unsupported pixel size %d\n", pixel_size);
goto done;
--
1.7.6.1
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