![]() ![]() The user can upload flv files and mp4 files, both of which play fine in the Flash UI before publishing. Vary the CRF between around 18 and 24 - the lower, the higher the bitrate.įfmpeg -i input.mp4 -vcodec libx264 -crf 20 output. We have a flash web-app that created interactive video, and are using ffmpeg to do some compression/resizing when a user 'publishes' their project. For example for a target size of 1 GB (one gigabyte, which is 8 gigabits) and 10 000 seconds of video (2 h 46 min 40 s), use a bitrate of 800 000 bit/s (800 kbit/s):Īdditional options that might be worth considering is setting the Constant Rate Factor, which lowers the average bit rate, but retains better quality. To see this technique applied using the older H.264 format, see this answer, quoted below for convenience:Ĭalculate the bitrate you need by dividing your target size (in bits) by the video length (in seconds). Note that lower CRF values correspond to higher bitrates, and hence produce higher quality videos.įfmpeg -i input.mp4 -vcodec libx265 -crf 28 output.mp4 To use it, replace the libx264 codec with libx265, and push the compression lever further by increasing the CRF value - add, say, 4 or 6, since a reasonable range for H.265 may be 24 to 30. Edit: H.265 (HEVC) is even better at compression (50 of H. To convert it and also compress the result, you can run: ffmpeg -i my-video.mov -vcodec h264 -acodec mp2 my-video. Note: This didn’t work with the ffmpeg version I had on my machine, so it’s best to always keep the program up to date.Since 2013 a video format much better than H.264 is widely available, namely H.265 (better in that it compresses more for the same quality, or gives higher quality for the same size). if you are targeting a certain output file size the best way is to use H.264 and Two-Pass encoding. A simple one-liner with ffmpeg to convert a Quicktime MOV file to MP4. In the example below, we generate output.mp4 which is twenty times the length of input.mp4.įfmpeg -stream_loop 20 -i input.mp4 -c copy output.mp4 Hardware accelerated ffmpeg compression using NVENC/QuickSync to decode and encode. The -stream_loop N option lets you loop (concatenate) the input video N times. FFmpeg-devel,v2,00/10 make QSV works with Intels oneVPL. ffmpeg -i inputfullhd.mp4 -vcodec libx265 -crf 28 -vsync 0 -vf scale800:-1 -preset medium output.mp4. My current working settings which get me to 500MB size in 20 minutes. Here’s the fun part: seeing the real magic of ffmpeg. ![]() See also this article from GIPHY Engineering. It is important for the videos to be completely in sync, so frame x in the input video matches frame x in output. This gist walks you through creating a GIF with ffmpeg and gifsicle. Ffmpeg mp4 compression how to#A more complicated solution is explained in this answer on the Super User StackExchange, along with an article detailing how to obtain better-looking GIFs from ffmpeg. ![]() For example, try the following command line: ffmpeg -i. This method tends to output poorer-quality GIFs. You can use FFmpeg to resize video to compress MP4/MOV/WebM etc. ![]() For some reason I couldn’t apply the setpts filter in a direct MOV to GIF pipeline, so I’m first making a sped-up MP4, then converting that to a GIF. The command above makes an MP4 video at twice the speed of the original MOV. Ffmpeg -i my-recording.mov -filter:v "setpts=0.5*PTS" my-recording-sped-up.mp4 ![]()
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