[FFmpeg-devel] [RFC] image2 and filename patterns

[Stefano Sabatini]

Hi,

I'm trying to address ticket #1969 and I'm collecting a few ideas and
seeing some (minor) nuisances.

My idea is to implement something like this:
ffmpeg INPUT -f image2 -pattern_type sequence_ts foo-%06d.png

which would force to encode the timestamps in microseconds (or
selectable) in the output files.

-pattern_type would be based on the image2 demuxer homonymous option,
values could be for example:
sequence
sequence_ts

Currently file overwrite is implemented through the not very intuitive
option named 'updatefirst', a possibly cleaner solution would be to
adopt another pattern like '-pattern_type file' (which would also
avoid pattern escaping on the user side).

The 'file' and 'sequence_ts' could be ported to the image2 demuxer
(the first would avoid the need for a -loop option at the application
level, for example in ffmpeg or in the movie filter).

In the mentioned ticket a pattern of the form '%pts' was suggested,
but I'm opposed to this for various reasons (need to convert %t
sequence to an av_get_frame_filename() pattern, impredictability in
case of arbitrary filenames provided by the user).
-- 
FFmpeg = Fast & Faithless Most Pitiful Evangelical Gadget