[FFmpeg-devel] [PATCH 11/17] avformat/mxfenc: Store locally whether DNXHD profile is interlaced

[Andreas Rheinhardt]

Tomas Härdin:
> tis 2021-11-09 klockan 19:01 +0100 skrev Andreas Rheinhardt:
>> It is just a flag per supported CID. So there is no reason to use
>> an avpriv function for this purpose.
> 
> This is data duplication. Honestly these ULs should probably live in
> dnxhddata.c.
> 

But aren't these ULs mxf-specific? So the right place for them is here
in libavformat.
And the amount of data duplicated is trivial; furthermore adding a new
DNXHD profile then and now requires modifications in two tables, so I
don't see a maintenance burden either.

>>
>> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
>> ---
>>  libavformat/mxfenc.c | 47 ++++++++++++++++++++++--------------------
>> --
>>  1 file changed, 23 insertions(+), 24 deletions(-)
>>
>> diff --git a/libavformat/mxfenc.c b/libavformat/mxfenc.c
>> index aa9857fcff..326ec6a7d6 100644
>> --- a/libavformat/mxfenc.c
>> +++ b/libavformat/mxfenc.c
>> @@ -2036,29 +2036,30 @@ static int
>> mxf_parse_prores_frame(AVFormatContext *s, AVStream *st, AVPacket *pk
>>  }
>>  
>>  static const struct {
>> -    int cid;
>> +    uint16_t cid;
>> +    uint8_t  interlaced;
>>      UID codec_ul;
>>  } mxf_dnxhd_codec_uls[] = {
> 
> Not sure if the narrowing of types here does any good. You might need
> to put cid and interlaced after codec_ul. On the other hand UID is
> uint8_t[] so perhaps it works out.
> 
The narrowing is irrelevant, as all cid values in use fit into an uint16_t.
Why would I need to put it at the end? Do you worry about padding
between interlaced and codec_ul? In this case it doesn't matter: It
would just be a matter of whether the padding is in the middle or at the
end of the structure.

- Andreas