[FFmpeg-devel] [PATCH] avformat/mxfenc: support XAVC long gop

[Thomas Mundt]

Am Sa., 30. März 2019 um 17:52 Uhr schrieb Baptiste Coudurier <
baptiste.coudurier at gmail.com>:

> Hi Thomas,
>
> > On Mar 29, 2019, at 1:11 PM, Thomas Mundt <tmundt75 at gmail.com> wrote:
> >
> >
> > […]
> >
> >>
> 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x0a,0x04,0x01,0x02,0x02,0x01,0x32,0x31,0x04
> >> }, 568832, 122, 0,  1 }, // AVC High 422 Intra RP2027 Class 100 1080/25p
> >> +    {{
> >>
> 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x0a,0x04,0x01,0x02,0x02,0x01,0x32,0x31,0x08
> >> }, 236544, 122, 0,  1 }, // AVC High 422 Intra RP2027 Class 100
> 720/59.94p
> >> +    {{
> >>
> 0x06,0x0E,0x2B,0x34,0x04,0x01,0x01,0x0a,0x04,0x01,0x02,0x02,0x01,0x32,0x31,0x09
> >> }, 284672, 122, 0,  1 }, // AVC High 422 Intra RP2027 Class 100 720/50p
> >>
> >
> > Maybe i miss something, but doesn´t the setting of the profile for all
> AVC
> > Intra codec ULs make the for-loop to always select the last AVC Intra
> > codec UL (720/50p) for AVC High 422 Intra?
>
> The frame size check prevents that.
>

The frame size check in the first condition of the for-loop works for fixed
frame size RP2027. However, with free frame size AVC High 422 Intra, the
second condition in the for-loop only checks for profile and intra-only.
Since the second condition doesn´t break the for-loop, the last UL with
matching profile and intra-only flag is set.

I wanted to test this behavior, so I applied this patch to
cf81284b1c14ef28d3f94e6d28c46188ba4e82f2, which is the last one that can be
compiled.
Unfortunately I was not able to produce any h264 mxf with this patch.
E.g. the following command works perfect without this patch:
ffmpeg -f lavfi -i testsrc=size=3840x2160:rate=50 -c:v libx264 -pix_fmt
yuv422p10 -x264-params keyint=1 -t 1 avc.mxf
With this patch I get errors: h264 profile not supported, could not get
h264 profile.
Same with other formats or long gop.
RP2027 Class 100 1080/50i shows the following error: frame size does not
match index unit size, 568832 != 0

Regards,
Thomas