mpegvideo: allocate edges when encoding.

Allocating edges will be removed from generic code, so the encoder must
handle this explicitly.
Merge commit '024db24912a39316b0ef0b7d793307d62da038f4'

* commit '024db24912a39316b0ef0b7d793307d62da038f4':
  mpegvideo: allocate edges when encoding.

Merged-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/diracdec: allocate edges internally instead of depending on CODEC_FLAG_EMU_EDGE being not set

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/vmnc: Check  that rectangles are within the picture

Prevents out of array accesses with CODEC_FLAG_EMU_EDGE

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/jpeg2000dec: calculate planar and pixelsize from pixel format descriptor

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/jpeg2000dec: fix error detection in pix_fmt_match()

Fixes out of array accesses with CODEC_FLAG_EMU_EDGE

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>