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avcodec: Use get_ue_golomb_long() when needed

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get_ue_golomb() cannot decode values larger than 8190 (the maximum
value that can be golomb encoded in 25 bits) and produces the error
"Invalid UE golomb code" if a larger value is encountered.  Use
get_ue_golomb_long() instead (which supports 63 bits, up to 4294967294)
when valid h264/hevc values can exceed 8190.

This updates decoding of the following values:   (maximum)
  first_mb_in_slice                                36863* for level 5.2
  abs_diff_pic_num_minus1                         131071
  difference_of_pic_nums_minus1                   131071
  idr_pic_id                                       65535
  recovery_frame_cnt                               65535
  frame_packing_arrangement_id                4294967294
  frame_packing_arrangement_repetition_period      16384
  display_orientation_repetition_period            16384

An alternative would be to modify get_ue_golomb() to handle encoded
values of up to 49 bits as was done for get_se_golomb() in a92816c.
In that case get_ue_golomb() could continue to be used for all of
these except frame_packing_arrangement_id.

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit is contained in:
Mark Harris
2015-12-28 23:04:08 -08:00
committed by Michael Niedermayer
parent efa666e0da
commit c51c08e0e7
7 changed files with 14 additions and 14 deletions
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2
libavcodec/h264_slice.c
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@@ -1688,7 +1688,7 @@ int ff_h264_decode_slice_header(H264Context *h, H264SliceContext *sl)
}
if (h->nal_unit_type == NAL_IDR_SLICE)
get_ue_golomb(&sl->gb); /* idr_pic_id */
get_ue_golomb_long(&sl->gb); /* idr_pic_id */
if (h->sps.poc_type == 0) {
int poc_lsb = get_bits(&sl->gb, h->sps.log2_max_poc_lsb);