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Why would you want your videos in the .3gp container to begin with? Its a very irrelevant format nowadays, there is practically no device that supports the 3gp container but not MP4 at the same time. Its nothing but a close derivative of MP4, they are very similar container formats holding the same codec. If you want to support a lot of devices using h264 in ...


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Just to add a bit to AJ Henderson correct answer. You do can compress in a lossless way with h264, this is the lossless predictive profile and is achieved by encoding with a CRF setting of 0. Though while you get lossless h264 compression that way you will endup with a larger file than your source file. Lossy compression cant be done twice without loosing ...


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You have a misunderstanding of how compression works. In all but a few specialized types of lossy compression, when you compress something a second time, even in a much higher quality level than previous encodings, you still lose additional quality. Using a slower encoding from the same original source with constant quality will often produce a smaller ...


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-preset Use the slowest preset that is fast enough that it does not drop frames. You can see if ffmpeg is dropping frames in the console output (if I recall correctly). Presets are: ultrafast, superfast, veryfast, faster, fast, medium, slow, slower, veryslow. -crf Use the highest -crf value that still provides an acceptable quality level. Range is 0-51. 0 ...


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You specify a preset and a quality value at the same time and by that overriding the preset. I would also recommend you don't encode with ffmpeg while capturing as this would be pretty slow on most PCs. The "error" in your ffmpeg commandline is the option -crf 1. CRF is a quality setting of x264 and the lower the value the higher the bitrate of the video ...


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The first thing I would try is to add -force_key_frames to your original command, drop the preset and lower the -crf value. The following example sets a key frame every second. ffmpg -i input.mov -c:v libx264 -profile main \ -force_key_frames expr:gte(t,n_forced*1) \ -crf 15 -pix_fmt yuv420p -an output.mp4 As a second resort I would use a series ...


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Although I am not sure if stderr will really help here because of the way that ffmpeg does its reporting, I can recommend the following pattern. Use the -progress [url] flag and parse it with the tool of your choice every 100ms or so. Here is something to get you started that (with a little tweaking) might do what you want: #!/bin/bash touch ...



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