h265parser/bitwriter: add some comments for ceil_log2 use

Validate that the length of field must be calculate with
ceil_logs2 and not bit storage.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/7429>
This commit is contained in:
Stéphane Cerveau 2024-10-09 13:47:41 -04:00 committed by GStreamer Marge Bot
parent 8f9ed667cd
commit ff9100eb4d
2 changed files with 8 additions and 2 deletions

View file

@ -1437,6 +1437,7 @@ _h265_slice_bit_writer_ref_pic_list_modification (const GstH265SliceHdr *
if (rpl_mod->ref_pic_list_modification_flag_l0) { if (rpl_mod->ref_pic_list_modification_flag_l0) {
for (i = 0; i <= slice->num_ref_idx_l0_active_minus1; i++) { for (i = 0; i <= slice->num_ref_idx_l0_active_minus1; i++) {
/* 7.4.7.2 list_entry_l0 */
WRITE_BITS (bw, rpl_mod->list_entry_l0[i], n); WRITE_BITS (bw, rpl_mod->list_entry_l0[i], n);
} }
} }
@ -1575,7 +1576,7 @@ _h265_bit_writer_slice_header (const GstH265SliceHdr * slice,
if (slice->pps->dependent_slice_segments_enabled_flag) if (slice->pps->dependent_slice_segments_enabled_flag)
WRITE_BITS (bw, slice->dependent_slice_segment_flag, 1); WRITE_BITS (bw, slice->dependent_slice_segment_flag, 1);
/* sice_segment_address parsing */ /* 7.4.7.1 slice_segment_address parsing */
WRITE_BITS (bw, slice->segment_address, n); WRITE_BITS (bw, slice->segment_address, n);
} }
@ -1610,6 +1611,7 @@ _h265_bit_writer_slice_header (const GstH265SliceHdr * slice,
sps->num_short_term_ref_pic_sets - 1) sps->num_short_term_ref_pic_sets - 1)
goto error; goto error;
/* 7.4.7.1 short_term_ref_pic_set_idx */
WRITE_BITS (bw, slice->short_term_ref_pic_set_idx, n); WRITE_BITS (bw, slice->short_term_ref_pic_set_idx, n);
} }
@ -1625,6 +1627,7 @@ _h265_bit_writer_slice_header (const GstH265SliceHdr * slice,
for (i = 0; i < limit; i++) { for (i = 0; i < limit; i++) {
if (i < slice->num_long_term_sps) { if (i < slice->num_long_term_sps) {
if (sps->num_long_term_ref_pics_sps > 1) { if (sps->num_long_term_ref_pics_sps > 1) {
/* 7.4.7.1 lt_idx_sps */
const guint n = const guint n =
gst_util_ceil_log2 (sps->num_long_term_ref_pics_sps); gst_util_ceil_log2 (sps->num_long_term_ref_pics_sps);
WRITE_BITS (bw, slice->lt_idx_sps[i], n); WRITE_BITS (bw, slice->lt_idx_sps[i], n);

View file

@ -926,6 +926,7 @@ gst_h265_slice_parse_ref_pic_list_modification (GstH265SliceHdr * slice,
if (rpl_mod->ref_pic_list_modification_flag_l0) { if (rpl_mod->ref_pic_list_modification_flag_l0) {
for (i = 0; i <= slice->num_ref_idx_l0_active_minus1; i++) { for (i = 0; i <= slice->num_ref_idx_l0_active_minus1; i++) {
/* 7.4.7.2 list_entry_l0 */
READ_UINT32 (nr, rpl_mod->list_entry_l0[i], n); READ_UINT32 (nr, rpl_mod->list_entry_l0[i], n);
CHECK_ALLOWED_MAX (rpl_mod->list_entry_l0[i], (NumPocTotalCurr - 1)); CHECK_ALLOWED_MAX (rpl_mod->list_entry_l0[i], (NumPocTotalCurr - 1));
} }
@ -2801,7 +2802,7 @@ gst_h265_parser_parse_slice_hdr (GstH265Parser * parser,
if (pps->dependent_slice_segments_enabled_flag) if (pps->dependent_slice_segments_enabled_flag)
READ_UINT8 (&nr, slice->dependent_slice_segment_flag, 1); READ_UINT8 (&nr, slice->dependent_slice_segment_flag, 1);
/* sice_segment_address parsing */ /* 7.4.7.1 slice_segment_address parsing */
READ_UINT32 (&nr, slice->segment_address, n); READ_UINT32 (&nr, slice->segment_address, n);
} }
@ -2835,6 +2836,7 @@ gst_h265_parser_parse_slice_hdr (GstH265Parser * parser,
(nal_reader_get_pos (&nr) - pos) - (nal_reader_get_pos (&nr) - pos) -
(8 * (nal_reader_get_epb_count (&nr) - epb_pos)); (8 * (nal_reader_get_epb_count (&nr) - epb_pos));
} else if (sps->num_short_term_ref_pic_sets > 1) { } else if (sps->num_short_term_ref_pic_sets > 1) {
/* 7.4.7.1 short_term_ref_pic_set_idx */
const guint n = gst_util_ceil_log2 (sps->num_short_term_ref_pic_sets); const guint n = gst_util_ceil_log2 (sps->num_short_term_ref_pic_sets);
READ_UINT8 (&nr, slice->short_term_ref_pic_set_idx, n); READ_UINT8 (&nr, slice->short_term_ref_pic_set_idx, n);
CHECK_ALLOWED_MAX (slice->short_term_ref_pic_set_idx, CHECK_ALLOWED_MAX (slice->short_term_ref_pic_set_idx,
@ -2855,6 +2857,7 @@ gst_h265_parser_parse_slice_hdr (GstH265Parser * parser,
for (i = 0; i < limit; i++) { for (i = 0; i < limit; i++) {
if (i < slice->num_long_term_sps) { if (i < slice->num_long_term_sps) {
if (sps->num_long_term_ref_pics_sps > 1) { if (sps->num_long_term_ref_pics_sps > 1) {
/* 7.4.7.1 lt_idx_sps */
const guint n = const guint n =
gst_util_ceil_log2 (sps->num_long_term_ref_pics_sps); gst_util_ceil_log2 (sps->num_long_term_ref_pics_sps);
READ_UINT8 (&nr, slice->lt_idx_sps[i], n); READ_UINT8 (&nr, slice->lt_idx_sps[i], n);