The ffmpeg project has four major applications: You'll find it used for transcoding, simple editing, video scaling, video post-production effects and standards compliance. It is command-line based and lets you handle video, audio, multimedia files, and streams. It's an opensource software project for working with audio and video. You may even have heard of it before you know exactly what it does, but it's used everywhere in video projects. If you work with video, you've heard of ffmpeg. The guide is to help ease you into using ffmpeg by explaining some basics about how scripts are structured, provide resources that will help you, walk you through some popular commands, and describe some common pitfalls you might encounter. If the sections for Mac and then Python don't apply to you, you may need to supplement this beginner's primer with other online content. Proceeding this way, I was able to have an efficient and robust way to split the video at key frames.Before we dive in, this beginner's manual will contain some general purpose information and then some information that's specific to Mac users and Python users.įfmpeg is an amazing set of tools, but it's also available in a variety of flavors. ffprobe -show_frames -select_streams v -print_format json=c=1 0001.wmvįrom the output of ffprobe get the pkt_dts_time of the frame just before that key frame.įfmpeg on the exported chunk of step 1, specifying the same input and output file, and specifying -ss 00:00:00 and -t. Choose closest keyframe after desired chunk size. Use ffprobe to find where the keyframes are. Because ffprobe is very verbose and can take several seconds or even minutes to output all key frames and there is no way to scope the range of frames we want from a lengthy video, I proceed into 5 steps:Įxport a video chunk from the original file, around the double of the desired chunk size. Here is the solution that I could get to work:Īs suggested by av501 and d33pika, I used ffprobe to find where the key frames are. In my own testing, it's worked well, although I haven't used it on anything longer than a few minutes and only in MP4 format.Īs stated on the official FFMPEG Docs, it has worked better for me to specify -ss timestart before -i input_file.ext, because it sets (or so I understand) the beginning of the generated video to the nearest keyframe found before your specified timestamp.Ĭhange your example to: ffmpeg.exe -ss 00:00:00 -i "C:\test.wmv" -t 00:00:05 -acodec copy -vcodec copy -async 1 -y "0000.wmv" This produces a series of numbered output files which are split into segments based on Key Frames. The latest builds of FFMPEG include a new option "segment" which does exactly what I think you need.įfmpeg -i INPUT.mp4 -acodec copy -f segment -vcodec copy -reset_timestamps 1 -map 0 OUTPUT%d.mp4 = extension of source video (e.g., mp4, mkv).Use the keyframes output above as input to ffmpeg.įfmpeg -i -codec copy -map 0 -f segment \.The output is comma-delimited string of keyframes. Use ffprobe and awk to identify the keyframes as close as possibleįfprobe -show_frames -select_streams v:0 \Īwk 'BEGIN print str. Using a newer build of ffmpeg, can achieve this by using ffprobe and the ffmpeg segment muxer.
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