From b654794d0970cacdf9d9e44d3a30c84a6879461c Mon Sep 17 00:00:00 2001 From: Wan-Teh Chang Date: Mon, 8 Apr 2024 15:22:20 -0700 Subject: [PATCH] Downgrade two new requirements to recommendations For backward compatibility, downgrade the following two new requirements in commit 86fb0ac OBUs that are not layer-specific must have the obu_extension_flag set to 0. ..., it is a requirement of bitstream conformance that obu_extension_flag is equal to 1 for all layer-specific OBUs in the coded video sequence. to recommendations OBUs that are not layer-specific should have the obu_extension_flag set to 0. ..., obu_extension_flag should be equal to 1 for all layer-specific OBUs in the coded video sequence. --- 07.bitstream.semantics.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/07.bitstream.semantics.md b/07.bitstream.semantics.md index dceec2a0..04a1db49 100644 --- a/07.bitstream.semantics.md +++ b/07.bitstream.semantics.md @@ -81,7 +81,7 @@ possible by preventing emulation of MPEG2 transport stream ids. Reserved units are for future use and shall be ignored by AV1 decoder. The column “Layer-specific” indicates if the corresponding OBU type is considered to be associated with -a specific layer ("Y"), or not ("N"). OBUs that are not layer-specific must have the obu_extension_flag set to 0. +a specific layer ("Y"), or not ("N"). OBUs that are not layer-specific should have the obu_extension_flag set to 0. Metadata OBU types may or may not be layer-specific, depending on the metadata type. The table in Section 6.7.1 specifies which types of metadata OBUs are layer-specific and which are not. @@ -195,7 +195,7 @@ It is a requirement of bitstream conformance that operating_point_idc[ i ] is no **Note:** This constraint means it is not allowed for two operating points to have the same value of operating_point_idc. {:.alert .alert-info } -If operating_point_idc[ op ] is not equal to 0 for any value of op from 0 to operating_points_cnt_minus_1, it is a requirement of bitstream conformance that obu_extension_flag is equal to 1 for all layer-specific OBUs in the coded video sequence. +If operating_point_idc[ op ] is not equal to 0 for any value of op from 0 to operating_points_cnt_minus_1, obu_extension_flag should be equal to 1 for all layer-specific OBUs in the coded video sequence. **seq_level_idx[ i ]** specifies the level that the coded video sequence conforms to when operating point i is selected.