img_format: take care of pixfmts that declare padding

A format could declare that some or all LSBs in a component are padding
bits by setting a non-0 AVComponentDescriptor.shift value. This means we
would interpret it incorrectly, because until now we always assumed all
regular formats have the padding in the MSBs.

Not a single format that does this actually exists, though. But a NV12
variant will be added later in FFmpeg.
This commit is contained in:
wm4 2016-01-07 16:00:38 +01:00
parent c19f634e6c
commit e2d90b383b
1 changed files with 9 additions and 2 deletions

View File

@ -148,6 +148,7 @@ struct mp_imgfmt_desc mp_imgfmt_get_desc(int mpfmt)
int planedepth[4] = {0};
int el_size = (pd->flags & AV_PIX_FMT_FLAG_BITSTREAM) ? 1 : 8;
bool need_endian = false; // single component is spread over >1 bytes
int shift = -1; // shift for all components, or -1 if not uniform
for (int c = 0; c < pd->nb_components; c++) {
AVComponentDescriptor d = pd->comp[c];
#if HAVE_AV_NEW_PIXDESC
@ -166,6 +167,10 @@ struct mp_imgfmt_desc mp_imgfmt_get_desc(int mpfmt)
desc.component_bits = depth;
if (depth != desc.component_bits)
desc.component_bits = 0;
if (c == 0)
shift = d.shift;
if (shift != d.shift)
shift = -1;
}
for (int p = 0; p < 4; p++) {
@ -234,7 +239,8 @@ struct mp_imgfmt_desc mp_imgfmt_get_desc(int mpfmt)
if ((desc.flags & (MP_IMGFLAG_YUV | MP_IMGFLAG_RGB))
&& (desc.flags & MP_IMGFLAG_BYTE_ALIGNED)
&& !(pd->flags & AV_PIX_FMT_FLAG_PAL))
&& !(pd->flags & AV_PIX_FMT_FLAG_PAL)
&& shift >= 0)
{
bool same_depth = true;
for (int p = 0; p < desc.num_planes; p++) {
@ -242,7 +248,8 @@ struct mp_imgfmt_desc mp_imgfmt_get_desc(int mpfmt)
desc.bpp[p] == desc.bpp[0];
}
if (same_depth && pd->nb_components == desc.num_planes) {
desc.component_full_bits = (desc.component_bits + 7) / 8 * 8;
desc.component_bits += shift;
desc.component_full_bits = (desc.component_bits + shift + 7) / 8 * 8;
if (desc.flags & MP_IMGFLAG_YUV) {
desc.flags |= MP_IMGFLAG_YUV_P;
} else {