avcodec/hevc_ps: improve check for missing default display window bitstream

Fixes ticket #6644

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: James Almer <jamrial@gmail.com>
This commit is contained in:
James Almer 2017-09-07 21:23:04 -03:00
parent 4ce99e96d6
commit c9a1cd08ea

View File

@ -550,7 +550,7 @@ err:
static void decode_vui(GetBitContext *gb, AVCodecContext *avctx,
int apply_defdispwin, HEVCSPS *sps)
{
VUI *vui = &sps->vui;
VUI backup_vui, *vui = &sps->vui;
GetBitContext backup;
int sar_present, alt = 0;
@ -618,13 +618,14 @@ static void decode_vui(GetBitContext *gb, AVCodecContext *avctx,
vui->field_seq_flag = get_bits1(gb);
vui->frame_field_info_present_flag = get_bits1(gb);
// Backup context in case an alternate header is detected
memcpy(&backup, gb, sizeof(backup));
memcpy(&backup_vui, vui, sizeof(backup_vui));
if (get_bits_left(gb) >= 68 && show_bits_long(gb, 21) == 0x100000) {
vui->default_display_window_flag = 0;
av_log(avctx, AV_LOG_WARNING, "Invalid default display window\n");
} else
vui->default_display_window_flag = get_bits1(gb);
// Backup context in case an alternate header is detected
memcpy(&backup, gb, sizeof(backup));
if (vui->default_display_window_flag) {
int vert_mult = 1 + (sps->chroma_format_idc < 2);
@ -651,18 +652,19 @@ static void decode_vui(GetBitContext *gb, AVCodecContext *avctx,
}
}
timing_info:
vui->vui_timing_info_present_flag = get_bits1(gb);
if (vui->vui_timing_info_present_flag) {
if( get_bits_left(gb) < 66) {
if( get_bits_left(gb) < 66 && !alt) {
// The alternate syntax seem to have timing info located
// at where def_disp_win is normally located
av_log(avctx, AV_LOG_WARNING,
"Strange VUI timing information, retrying...\n");
vui->default_display_window_flag = 0;
memset(&vui->def_disp_win, 0, sizeof(vui->def_disp_win));
memcpy(vui, &backup_vui, sizeof(backup_vui));
memcpy(gb, &backup, sizeof(backup));
alt = 1;
goto timing_info;
}
vui->vui_num_units_in_tick = get_bits_long(gb, 32);
vui->vui_time_scale = get_bits_long(gb, 32);
@ -680,6 +682,15 @@ static void decode_vui(GetBitContext *gb, AVCodecContext *avctx,
vui->bitstream_restriction_flag = get_bits1(gb);
if (vui->bitstream_restriction_flag) {
if (get_bits_left(gb) < 8 && !alt) {
av_log(avctx, AV_LOG_WARNING,
"Strange VUI bitstream restriction information, retrying"
" from timing information...\n");
memcpy(vui, &backup_vui, sizeof(backup_vui));
memcpy(gb, &backup, sizeof(backup));
alt = 1;
goto timing_info;
}
vui->tiles_fixed_structure_flag = get_bits1(gb);
vui->motion_vectors_over_pic_boundaries_flag = get_bits1(gb);
vui->restricted_ref_pic_lists_flag = get_bits1(gb);
@ -689,6 +700,16 @@ static void decode_vui(GetBitContext *gb, AVCodecContext *avctx,
vui->log2_max_mv_length_horizontal = get_ue_golomb_long(gb);
vui->log2_max_mv_length_vertical = get_ue_golomb_long(gb);
}
if (get_bits_left(gb) < 1 && !alt) {
// XXX: Alternate syntax when sps_range_extension_flag != 0?
av_log(avctx, AV_LOG_WARNING,
"Overread in VUI, retrying from timing information...\n");
memcpy(vui, &backup_vui, sizeof(backup_vui));
memcpy(gb, &backup, sizeof(backup));
alt = 1;
goto timing_info;
}
}
static void set_default_scaling_list_data(ScalingList *sl)