-quality good Sets encoding speed for the VP8 encoder. -codec:v Specifies the video encoder to be used, in our case that is libvpx VP8 library. 
High-quality SD video for archive/storage (PAL at 1Mbit/s in high profile): 1įfmpeg -i inputfile.avi -codec:v libx264 -profile:v high -preset slower -b:v 1000k -vf scale=-1:576 -threads 0 -codec:a libfdk_aac -b:a 196k output.mp4
-an | disables audio, audio processing has no effect on first pass so it’s best to disable it to not waste CPUįfmpeg -i input_file.avi -codec:v libx264 -profile: high -preset slow -b:v 500k -maxrate 500k -bufsize 1000k -vf scale=-1:480 -threads 0 -codec:a libfdk_aac -b:a 128k output_file.mp4ģ60p video for older mobile phones (360p at 250kbit/s in baseline profile) 1įfmpeg -i inputfile.avi -codec:v libx264 -profile:v baseline -preset slow -b:v 250k -maxrate 250k -bufsize 500k -vf scale=-1:360 -threads 0 -codec:a libfdk_aac -b:a 96k output.mp4Ĥ80p video for iPads and tablets (480p at 400kbit/s in main profile): 1įfmpeg -i inputfile.avi -codec:v libx264 -profile:v main -preset slow -b:v 400k -maxrate 400k -bufsize 800k -vf scale=-1:480 -threads 0 -codec:a libfdk_aac -b:a 128k output.mp4. -pass | tells FFmpeg to process video in multiple passes and sets the current pass. -codec:a libfdk_aac | tells FFmpeg to encode audio to AAC using libfdk-aac library. -threads 0 | tells libx264 to choose optimal number of threads to encode, which will make sure all your processor cores in the computer are used. “720:480” would resize video to 720x480, “-1” means “resize so the aspect ratio is same.” Usually you set only height of the video, so for 380p you set “scale=-1:380”, for 720p “scale=-1:720” etc. -vf scale | applies “scale” filter, which resizes video to desired resolution. Very useful for web - setting this to bitrate and 2x bitrate gives good results. -maxrate and -bufsize | forces libx264 to build video in a way, that it could be streamed over 500kbit/s line considering device buffer of 1000kbits. 
Other valid options are: ultrafast, superfast, veryfast, faster, fast, medium, slow, slower, veryslow, placebo (never use this one) “slow” is a good balance between encoding time and quality.
-preset slow | sets encoding preset for x264 – slower presets give more quality at same bitrate, but need more time to encode. 
-profile:v high | sets H.264 profile to “High” as per Step 2. -codec:v libx264 | tells FFmpeg to encode video to H.264 using libx264 library. -i | this specifies the name of input file. Brew install ffmpeg -with-libvpx -with 生成 mp4 参数说明
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