[FFmpeg-devel] Merging AV_CODEC_ID_IFF_ILBM and AV_CODEC_ID_IFF_BYTERUN1

[Paul B Mahol]

On 11/21/12, Peter Ross <pross at xvid.org> wrote:
> On Wed, Nov 21, 2012 at 09:40:59AM +0000, Paul B Mahol wrote:
>> On 11/21/12, Peter Ross <pross at xvid.org> wrote:
>> > Currently the IFF bitmap decoder is split across two AV_CODEC_IDs.
>> > Bitmaps with compression type 0 got to AV_CODEC_ID_IFF_ILBM, and
>> > compression type 1 goes to AV_CODEC_ID_BYTERUN1.
>> >
>> > The compression type value is passed to the decoder via an extra-data
>> > structure, so the separate AV_CODEC_IDs are not required. (Early
>> > on this wasn't the case).
>> >
>> > How could the decoders be merged without breaking API compatibility.
>> > There is at least one more compression type that I would like to add to
>> > the IFF bitmap. Adding yet another AV_CODEC_ID for this would seem
>> > silly.
>>
>> And would make supporting ANIMs that may change (from one compression type
>> to
>> another impossible - like ilbm <-> byterun1 but I yet have to find such
>> sample).
>>
>> Proposed solution: add new codec id and use it in our lavf, others keep
>> just
>> for compatibility sake.
>
> Okay. The compression data structure could be sent via
> AVPacket.side_data[].
> That would, in theory, support the ANIM use case.

Not needed, it could be just put at beginning of packet.