Comment 5 for bug 1436296

In the meanwhile FFmpeg 2.5.6 with some more fixes has been released.

version 2.5.6
- avcodec/atrac3plusdsp: fix on stack alignment
- ac3: validate end in ff_ac3_bit_alloc_calc_mask
- aacpsy: avoid psy_band->threshold becoming NaN
- aasc: return correct buffer size from aasc_decode_frame
- msrledec: use signed pixel_ptr in msrle_decode_pal4
- swresample: Allow reinitialization without ever setting channel layouts (cherry picked from commit 80a28c7509a11114e1aea5b208d56c6646d69c07)
- swresample: Allow reinitialization without ever setting channel counts
- avcodec/h264: Do not fail with randomly truncated VUIs
- avcodec/h264_ps: Move truncation check from VUI to SPS
- avcodec/h264: Be more tolerant to changing pps id between slices
- avcodec/aacdec: Fix storing state before PCE decode
- avcodec/h264: reset the counts in the correct context
- avcodec/h264_slice: Do not reset mb_aff_frame per slice
- avcodec/h264: finish previous slices before switching to single thread mode
- avcodec/h264: Fix race between slices where one overwrites data from the next
- avcodec/h264_refs: Do not set reference to things which do not exist
- avcodec/h264: Fail for invalid mixed IDR / non IDR frames in slice threading mode
- h264: avoid unnecessary calls to get_format
- avcodec/msrledec: restructure msrle_decode_pal4() based on the line number instead of the pixel pointer

I updated the vivid branch on Alioth [1].

It builds fine in a vivid chroot, including build time tests.
Attached is a debdiff from 2.5.4-1.

1: https://anonscm.debian.org/cgit/collab-maint/ffmpeg.git/log/?h=vivid