[FFmpeg-devel] [PATCH 1/3] spherical: Add tiled equirectangular type and projection-specific properties

[James Almer]

On 2/14/2017 5:52 PM, Vittorio Giovara wrote:
> On Fri, Feb 10, 2017 at 6:25 PM, Michael Niedermayer
> <michael at niedermayer.cc> wrote:
>> On Fri, Feb 10, 2017 at 04:11:43PM -0500, Vittorio Giovara wrote:
>>> Signed-off-by: Vittorio Giovara <vittorio.giovara at gmail.com>
>>> ---
>>> This should help not losing details over muxing and allows
>>> callers to get additional information in a clean manner.
>>>
>>> Please keep me in CC.
>>> Vittorio
>>>
>>>  doc/APIchanges        |  5 +++++
>>>  ffprobe.c             | 11 ++++++++--
>>>  libavformat/dump.c    | 10 +++++++++
>>>  libavutil/spherical.h | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++
>>>  libavutil/version.h   |  2 +-
>>>  5 files changed, 81 insertions(+), 3 deletions(-)
>>
>> breaks fate
>>
>> --- ./tests/ref/fate/matroska-spherical-mono    2017-02-10 23:43:51.993432371 +0100
>> +++ tests/data/fate/matroska-spherical-mono     2017-02-11 00:24:10.297483318 +0100
>> @@ -7,7 +7,7 @@
>>  [/SIDE_DATA]
>>  [SIDE_DATA]
>>  side_data_type=Spherical Mapping
>> -side_data_size=16
>> +side_data_size=56
>>  projection=equirectangular
>>  yaw=45
>>  pitch=30
>> Test matroska-spherical-mono failed. Look at tests/data/fate/matroska-spherical-mono.err for details.
>> make: *** [fate-matroska-spherical-mono] Error 1
> 
> Ah I didn't notice, it is fixed in the next commit, but I'll amend this one too.
> 
> 
> I didn't see any comment/discussion, should I assume it is ok?
> Please CC, thank you.

These are a lot of projection specific fields. It worries me as the
spec may change in the future with new fields added or existing
fields changing purpose. Not to mention the Mesh projection, which
has like fifty specific fields of its own.

Wouldn't it be a better idea to export the binary data of the
equi/cbmp/mesh boxes into an extradata-like field in the
AVSphericalMapping struct, and let the downstream application parse
it instead?

That way you can skip adding the extra Equirectangular enum, and
also add the Mesh one.