FFmpeg's isaTTY check makes programatically parsing stderr impossible
|Reported by:||tommedema||Owned by:||michael|
|Version:||git-master||Keywords:||console tty loglevel programming interaction debug progress|
|Blocking:||Reproduced by developer:||no|
|Analyzed by developer:||no|
What you were trying to accomplish (e.g., "I am trying to transcode from this format to that format...")
I am programatically spawning FFmpeg, trying to parse "progress" info from stderr using the following regular expression:
An example entry:
52kB time=00:00:11.43 bitrate= 37.4kbits/s
These entries are displayed just fine when I run ffmpeg in the console (TTY).
The problem you encountered (e.g., "ffmpeg crashed" or "The output video was all green")
When I spawn a ffmpeg process programatically, ffmpeg refuces to listen to the -loglevel command because it performs a is-a-tty check and seems to not provide as much debug information when it is not a TTY (which is the case when spawning programatically and piping stderr data to certain streams).