[FFmpeg-devel] [PATCH] lavc/h2645_parse: Don't automatically remove nuh_layer_id > 0 packets

[James Almer]

On 12/2/2019 12:07 AM, James Almer wrote:
> On 12/1/2019 11:48 PM, Andriy Gelman wrote:
>> From: Andriy Gelman <andriy.gelman at gmail.com>
>>
>> HEVC standard supports multi-layer streams (ITU-T H.265 02/2018 Annex
>> F). Each NAL unit belongs to a particular layer defined by nuh_layer_id
>> in the header.
>>
>> Currently, all NAL units that do not belong to a base layer are
>> automatically removed in ff_h2645_packet_split(). Some data may
>> therefore be lost when future filters/decoders are designed to support
>> multi-layer streams.
>>
>> A better approach is to forward nuh_layer_id > 0 packets and let blocks
>> down the chain decide how to process them. The condition to remove
>> packets has been moved to hevcdec and cbs bsf where such packets are
>> currently not supported.
>> ---
>>  libavcodec/cbs_h2645.c   | 3 +++
>>  libavcodec/h2645_parse.c | 7 +++----
>>  libavcodec/h2645_parse.h | 5 +++++
>>  libavcodec/hevc_parse.c  | 2 ++
>>  libavcodec/hevc_parser.c | 2 ++
>>  libavcodec/hevcdec.c     | 2 +-
>>  6 files changed, 16 insertions(+), 5 deletions(-)
> 
> Missing changes to extract_extradata_bsf.

Actually, probably not. Skipping them there may result in lost data in
the output packet.