[FFmpeg-user] Questions about "Cannot allocate memory"

[Moritz Barsnick]

On Sun, Jan 31, 2021 at 20:28:46 -0500, Mark Filipak (ffmpeg) wrote:
> In lines like this:
> "frame= 1588 fps=0.5 q=22.4 size=   23296kB time=00:01:06.02 bitrate=2890.3kbits/s speed=0.0225x"
> Regarding "frame=":
>   Why are many frame numbers repeated?
>   Why are many frame numbers skipped?
>   How can a particular frame number appear twice with 2 different PTSs?
> Regarding "size=...kB":
>   Why does "size=...kB" only increase?
>   If it is cummulative, why is it cummulative?
>   If it is cummulative to indicate buffering, why doesn't it ever decrease?
>   If it is important, why isn't it in 'bytes' instead of 'kB'?

It's a report/statics line for convenience. It's written to standard
out, and can be written to file, in regular periods, default 0.5s,
controlled by option "stats_period".

>   Why are many frame numbers repeated?

Presumably because your encoding is so slow (0.0225x) and you don't get
a new frame every interval.

>   Why are many frame numbers skipped?

It's a periodic report.

>   How can a particular frame number appear twice with 2 different PTSs?

Presumably because one input frame corresponds to various output
frames? (You're converting from 24/1.001 to 60/1.001, AFAICT.)

Who says it's PTS?

>   Why does "size=...kB" only increase?

Because it's the total amount of encoded (or muxed?) data. It must be
monotonic.

>   If it is cummulative, why is it cummulative?

Because that's a design decision, presumably.

(If you claim the stats can be confusing and not well explained, I tend
to agree.)

Cheers,
Moritz.