shithub: dav1d

Info  •  Files  •  Log  •  Branches

Check frame IDs for reference and "show_existing" frames

--- a/src/obu.c

+++ b/src/obu.c

@@ -374,8 +374,11 @@

         hdr->existing_frame_idx = dav1d_get_bits(gb, 3);

         if (seqhdr->decoder_model_info_present && !seqhdr->equal_picture_interval)

             hdr->frame_presentation_delay = dav1d_get_bits(gb, seqhdr->frame_presentation_delay_length);

-        if (seqhdr->frame_id_numbers_present)

+        if (seqhdr->frame_id_numbers_present) {

             hdr->frame_id = dav1d_get_bits(gb, seqhdr->frame_id_n_bits);

+            Dav1dFrameHeader *const ref_frame_hdr = c->refs[hdr->existing_frame_idx].p.p.frame_hdr;

+            if (!ref_frame_hdr || ref_frame_hdr->frame_id != hdr->frame_id) return DAV1D_ERR(EINVAL);

+        }

         return 0;

     }

@@ -550,8 +553,12 @@

         for (int i = 0; i < 7; i++) {

             if (!hdr->frame_ref_short_signaling)

                 hdr->refidx[i] = dav1d_get_bits(gb, 3);

-            if (seqhdr->frame_id_numbers_present)

-                dav1d_get_bits(gb, seqhdr->delta_frame_id_n_bits);

+            if (seqhdr->frame_id_numbers_present) {

+                const int delta_ref_frame_id_minus_1 = dav1d_get_bits(gb, seqhdr->delta_frame_id_n_bits);

+                const int ref_frame_id = (hdr->frame_id + (1 << seqhdr->frame_id_n_bits) - delta_ref_frame_id_minus_1 - 1) & ((1 << seqhdr->frame_id_n_bits) - 1);

+                Dav1dFrameHeader *const ref_frame_hdr = c->refs[hdr->refidx[i]].p.p.frame_hdr;

+                if (!ref_frame_hdr || ref_frame_hdr->frame_id != ref_frame_id) goto error;

+            }

         }

         const int use_ref = !hdr->error_resilient_mode &&

                             hdr->frame_size_override;