[0] install ffmpeg
// Linux system installed
sudo the Add-APT-Repository ppa: kirillshkrogalev / ffmpeg- the Next sudo APT- GET Update sudo APT-GET install ffmpeg
// check the version number
ffmpeg -version
// installation under win10 1 download 2 install 3 bin directory configured into the system environment variables 4 win R to enter DOS, enter ffmpeg to see if the installation was successful
[1] compressed video / audio
-i FFmpeg " oldFile.mp3 " -b: A 128K -acodec MP3 - Ar 44100 -ac . 1 " newFile.mp3 "
// -b: A 128K rate, 128/192 / 320. Kbp / S
// - MP3 acodec encoding
// - ar 44100 sample rate, default 44100HZ
[2] for video watermarking
[3] The combined video / audio
[4] capture video / audio
[5] format conversion
https://www.cnblogs.com/xiaofengfeng/p/3573025.html
[6] separating the video / audio
-i input_file -vcodec Copy -an FFmpeg output_file_video // separates a video stream FFmpeg -i input_file -acodec Copy -vn output_file_audio // separate audio stream
[7] set the frame rate
FPS -r // set the default frame rate of 25
-b: A 128K // set rate
Related Bowen: https://www.cnblogs.com/tyqing/p/6040288.html