[Yunxiang book club No. 13] Chapter V ffmpeg common methods for viewing media information and processing audio and video files

FFmpeg The engineering plan of

• Audio files and video files transcoding Processing is generally called Multimedia processing .
• Huawei cloud also has corresponding media processing services ——Media Processing Center, abbreviation MPC
• MPC It is a multimedia data processing service , Build based on Huawei cloud computing services , To solve the inevitable high investment cost of customers' self built audio and video processing capacity 、 High technical barriers , Help customers focus on building business capabilities , Fast delivery online .

FFmpeg Video processing engineering scheme

• Video coding ： Support H264 and H265, Default H264
• The resolution of the （ Video width * Video height ）： Both width and height are zero , Then transcoding is output according to the original resolution ; If one of them is 0, Then compress according to the original size ratio
• Frame rate ：5~30 or 0
• Bit rate （ Bit rate ）：40~30000
• I Maximum frame spacing ： In keyframes I The maximum interval between frames ,2~5
• Maximum continuous B frame ：0~7
• Coding grade ：H264（BASE、MAIN、HIGH）、H265（MAIN）

FFmpeg Audio processing engineering scheme

• Audio encoding ： Support AAC、HE_AAC1、HE_AAC2 and MP3, The default is AAC
• Sampling rate ： Support AUTO、22050Hz、32000Hz、44100Hz、48000Hz、96000Hz, Default AUTO
• Bit rate （ Bit rate ）：8~1000 or 0
• Track number ： Support 1、2
  

FFmpeg transcoding

• How to use it FFmpeg Realize some audio and video processing functions of some Huawei cloud media processing services , Including transcoding capability 、 Video parameters 、 Three parts of audio parameters .

Audio transcoding

ffmpeg -i  juvenile .mp3 -acodec aac -ab 3000 -ac 1 -ar 8000 output.aac

Video transcoding

ffmpeg -i big_buck_bunny.mp4 -vcodec h263 -b:v 256000 -r 15 -s 352x288 -acodec copy output.ts

Summary

• This chapter mainly studies FFmpeg Audio and video processing engineering scheme , as well as FFmpeg Audio transcoding and video transcoding .