On date Tuesday 2007-08-28 13:00:06 -0400, hari jayaram encoded:

Hi I was wondering how to get at the bitrate and fps numbers for an input video to fine tune the transcode process. I know that ffmpeg writes these numbers to stdout when you run it. But is there a way to just query this information without doing a mock transcode.

Also I am curious how do you get the statistics like the one Stefano sabatini mentioned in a post related to an mov file

Stefano Sabatini said

In the case of the original file you have: I frames mean size: 4208.91472868217 I frames number: 129 P frames mean size: 2713.66288017589 P frames number: 2729

With the FLV encoded by ffmpeg you get: I frames mean size: 9357.03571428572 I frames number: 140 P frames mean size: 3458.86428834131 P frames number: 2719

Attached there is the last working version of a project of mine, named ffprobe, which is actually implemented as a patch to FFmpeg (but maybe would be a better idea to release it as a stand-alone project). It's a work in progress, thus is way far from perfection and there is a number of problems which need to be fixed. It basically works by outputting on stdout a series of statistics, then a textual filter (like tools/plot-video-frames-stats.pl in the patch) is supposed to parse it and print out something meaningful. I started to hack it because I need to analyze some media files and couldn't find anything which already did this and was sufficiently general (many formats supported), and the FF-mpeg libraries seem the ideal candidate to perform such analysis in a general way. If someone can get it compiling and try it I'll be grateful for any feedback.

I want to really understand the transcode process so any inputs I can get will be very helpful

Cheers. -- ffmpeg-user random tip #4 ffmpeg -i FILE prints information about the container format and the streams in a file.