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I need convert MP4 to webm with ffmpeg. So, i use :
ffmpeg -i input.mp4 -c:v libvpx -crf 10 -b:v 1M -c:a libvorbis output.webm
But it's very long.
Is there faster ?
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If your CPU usage is still low after FFmpeg has managed to seek to the defined point in the video, it's likely due to one or more of the filters you're using. Some filters may not be able to use all the available CPU threads, and some filters aren't even multi-threaded.
Use the -speed number (e.g. 8), not the -preset setting (e.g. ultrafast ). The latter is for x264/x265 encoding. A Higher number means faster encoding, so ultrafast would map to 8 or so.
If you need to turn your files from . mp4 to . webm, all you need is an appropriate piece of software – like Movavi Video Converter. This is the best MP4-to-WebM converter for Mac.
WebM vs MP4: File Size and Quality But since WebM is specially designed for Internet, the compression ratio of WebM is generally higher than MP4 in theory, which leads to more original quality loss than MP4. And the file size of WebM is a little bit smaller than MP4.
libvpx is a relatively slow encoder. According to the VP8 Encode Parameter Guide: Encode Quality vs. Speed, you can use the -cpu-used option to increase encoding speed. A higher value results in faster encoding but lower quality:
Setting a value of 0 will give the best quality output but is extremely slow. Using 1 (default) or 2 will give further significant boosts to encode speed, but will start to have a more noticeable impact on quality and may also start to effect the accuracy of the data rate control. Setting a value of 4 or 5 will turn off "rate distortion optimisation" which has a big impact on quality, but also greatly speeds up the encoder.
Alternatively, it appears that VA-API can be utilized for hardware accelerated VP8 encoding, but I have no experience with this.
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