shithub: dav1d

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obu: add support for OBUs with no size field

--- a/src/obu.c

+++ b/src/obu.c

@@ -1042,7 +1042,6 @@

     const enum ObuType type = dav1d_get_bits(&gb, 4);

     const int has_extension = dav1d_get_bits(&gb, 1);

     const int has_length_field = dav1d_get_bits(&gb, 1);

-    if (!has_length_field) goto error;

     dav1d_get_bits(&gb, 1); // reserved

     if (has_extension) {

         dav1d_get_bits(&gb, 3); // temporal_layer_id

@@ -1052,15 +1051,18 @@

     // obu length field

     unsigned len = 0, more, i = 0;

-    do {

-        more = dav1d_get_bits(&gb, 1);

-        unsigned bits = dav1d_get_bits(&gb, 7);

-        if (i <= 3 || (i == 4 && bits < (1 << 4)))

-            len |= bits << (i * 7);

-        else if (bits)

-            goto error;

-        if (more && ++i == 8) goto error;

-    } while (more);

+    if (has_length_field)

+        do {

+            more = dav1d_get_bits(&gb, 1);

+            unsigned bits = dav1d_get_bits(&gb, 7);

+            if (i <= 3 || (i == 4 && bits < (1 << 4)))

+                len |= bits << (i * 7);

+            else if (bits)

+                goto error;

+            if (more && ++i == 8) goto error;

+        } while (more);

+    else

+        len = in->sz - 1 - has_extension;

     if (gb.error) goto error;

     const unsigned init_bit_pos = dav1d_get_bits_pos(&gb);