[FFmpeg-devel] [FFMPEG DEVEL] [PATCH v2] fftools/ffprobe: Add S12M Timecode output as side data (such as SEI TC)

[Marton Balint]

On Sat, 18 May 2019, Antonin Gouzer wrote:

> Thank you for your response,
> I don't have any example of such a file.
> I was thinking that GOP timecode was reserved to MPEG2 files and S12M
> to H265/H264 files ?
>
> In every writer the type of timecode is already an attribute: side_data_type.
> With the actual xsd the result should be, with the XML writer:
>
> <side_data_list>
>                <side_data side_data_type="SMPTE 12-1 timecode"
> timecode="00:03:25:03"/>
>                <side_data side_data_type="GOP timecode"
> timecode="00:03:25:03"/>
> </side_data_list>
>
> That should be ok don't you think ?

Ah, OK then.

I see another issue though: what if S12M side data has more than one 
timecode in it? Having the same attirbute multiple times in an XML tag is 
not valid.

>> On Fri, 17 May 2019, Antonin Gouzer wrote:
>>
>> > Thanks in advance.
>> > ---
>> > fftools/ffprobe.c | 8 ++++++++
>> > 1 file changed, 8 insertions(+)
>> >
>> > diff --git a/fftools/ffprobe.c b/fftools/ffprobe.c
>> > index dea489d02e..4763ce6d98 100644
>> > --- a/fftools/ffprobe.c
>> > +++ b/fftools/ffprobe.c
>> > @@ -2199,6 +2199,14 @@ static void show_frame(WriterContext *w, AVFrame *frame, AVStream *stream,
>> >                 char tcbuf[AV_TIMECODE_STR_SIZE];
>> >                 av_timecode_make_mpeg_tc_string(tcbuf, *(int64_t *)(sd->data));
>> >                 print_str("timecode", tcbuf);
>> > +            } else if (sd->type == AV_FRAME_DATA_S12M_TIMECODE && sd->size >= 8) {
>> > +                uint32_t *tc = (uint32_t*)sd->data;

An assert makes sense here to check if tc[0] <= 3.

>> > +                for (int j = 1; j <= tc[0]; j++) {
>> > +                char tcbuf[AV_TIMECODE_STR_SIZE];
>> > +                av_timecode_make_smpte_tc_string(tcbuf, tc[j], 0);
>> > +                print_str("timecode", tcbuf);
>> > +                }
>> > +                break;

Why the break?

Regards,
Marton