[FFmpeg-user] ffmpeg reported fps different than actual file's

[James Girotti]

On Wed, Aug 2, 2017 at 3:09 PM, tasos <tasoss at trigonongroup.com> wrote:

> Hello again.
> A lot of information and i'm trying to process them.
> I know a few basic things about video processing in general.
> Anyway,the specific dvb source channel is quite strange or at least this
> is how it looks
> to me.
>
>> Is this the ffprobe output from the file or your DVB capture device? I
>> politely request you provide full command lines and output in the future.
>>
>
> That was from the file.
>
>
> Can you dump directly from the device to file without using ffmpeg? I.E.:
>>
> Yes i can.
>

That should make troubleshooting much easier! Glad you're able to do that.


>
> ffprobe -v error -select_streams v:0 -show_entries  \
>> stream=r_frame_rate,avg_frame_rate -of default=nw=1 ./foo.ts
>>
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] SPS unavailable in decode_picture_timing
>> [h264 @ 0x4088420] non-existing PPS 0 referenced
>> [h264 @ 0x4088420] decode_slice_header error
>> [h264 @ 0x4088420] no frame!
>> [h264 @ 0x4088420] mmco: unref short failure
>> r_frame_rate=25/1repeated 1 times
>> avg_frame_rate=25/1
>> r_frame_rate=25/1
>> avg_frame_rate=25/1
>>
> Vlc reports 25fps! And btw the video is interlaced.
>

Based on that it appears that your device is outputting an h264 video
stream @ exactly 25 fps, did you run the other command I recommended to get
the time base values?


> The fact that i used avi doesn't matter.I mean i could use something else.
> Do you recommend mkv ?
>

I personally use MKV as much as possible, it supports the widest range of
audio/video/subtitle formats. I can always remux to another container if
absolutely needed. The only negative I have come across is the metadata
implementation/specification. From what I've read different programs tend
to use slightly different metadata tags for the same piece of data. Not
really a problem for me though, haven't run into it.


> Moreover,is the above raw output from the device the best way to be sure
> about the fps etc ?
>

I think it's likely the best and most accurate. You might want to research
the exact device and v4l driver (I'm assuming you're on Linux) on
capabilities/expected output.


> Thanks for the long reply and the time you spent on this. Of course
> i have understood a few things better but i should read it again a few
> more times
> in order to completely get it :)
>

It was fun and I learned how to get output from ffprobe that I can
understand better! Hopefully, it will help others too.


> This whole thing about fps started when i had audio delay problems.
> The problem appeared only when i was using -c:v h264_cuvid .
> And then,i somehow thought about fps and audio.
> But i should post another question about the audio delay problem...


Yes, start another question/thread. I already have some ideas there too,
based on my own personal struggles.

-JG