h264_ps: export actual height in MBs as SPS.mb_height

Currently, SPS.mb_height is actually what the spec calls
PicHeightInMapUnits, which is half the frame height when interlacing is
allowed. Calling this 'mb_height' is quite confusing, and there are at
least two associated bugs where this field is treated as the actual
frame height - in the h264 parser and in the code computing maximum
reordering buffer size for a given level.

Fix those issues (and avoid possible future ones) by exporting the real
frame height in this field.
This commit is contained in:
Anton Khirnov 2016-07-02 16:48:26 +02:00
parent 99cf943339
commit a8cbe5a0cc
3 changed files with 13 additions and 4 deletions

View File

@ -439,6 +439,15 @@ int ff_h264_decode_seq_parameter_set(GetBitContext *gb, AVCodecContext *avctx,
sps->gaps_in_frame_num_allowed_flag = get_bits1(gb);
sps->mb_width = get_ue_golomb(gb) + 1;
sps->mb_height = get_ue_golomb(gb) + 1;
sps->frame_mbs_only_flag = get_bits1(gb);
if (sps->mb_height >= INT_MAX / 2) {
av_log(avctx, AV_LOG_ERROR, "height overflow\n");
goto fail;
}
sps->mb_height *= 2 - sps->frame_mbs_only_flag;
if ((unsigned)sps->mb_width >= INT_MAX / 16 ||
(unsigned)sps->mb_height >= INT_MAX / 16 ||
av_image_check_size(16 * sps->mb_width,
@ -447,7 +456,6 @@ int ff_h264_decode_seq_parameter_set(GetBitContext *gb, AVCodecContext *avctx,
goto fail;
}
sps->frame_mbs_only_flag = get_bits1(gb);
if (!sps->frame_mbs_only_flag)
sps->mb_aff = get_bits1(gb);
else

View File

@ -56,7 +56,8 @@ typedef struct SPS {
int ref_frame_count; ///< num_ref_frames
int gaps_in_frame_num_allowed_flag;
int mb_width; ///< pic_width_in_mbs_minus1 + 1
int mb_height; ///< pic_height_in_map_units_minus1 + 1
///< (pic_height_in_map_units_minus1 + 1) * (2 - frame_mbs_only_flag)
int mb_height;
int frame_mbs_only_flag;
int mb_aff; ///< mb_adaptive_frame_field_flag
int direct_8x8_inference_flag;

View File

@ -926,11 +926,11 @@ static int h264_init_ps(H264Context *h, const H264SliceContext *sl)
h->avctx->refs = sps->ref_frame_count;
if (h->mb_width != sps->mb_width ||
h->mb_height != sps->mb_height * (2 - sps->frame_mbs_only_flag))
h->mb_height != sps->mb_height)
needs_reinit = 1;
h->mb_width = sps->mb_width;
h->mb_height = sps->mb_height * (2 - sps->frame_mbs_only_flag);
h->mb_height = sps->mb_height;
h->mb_num = h->mb_width * h->mb_height;
h->mb_stride = h->mb_width + 1;