Video transcoding is a process of first decoding and then encoding, thereby converting the original video into the video we need. This conversion may include various formats (mp4/avi/flv, etc.), resolution, bit rate, frame rate, etc. In traditional video transcoding, a very commonly used tool is FFmpeg. FFmpeg is a set of open source computer programs that can be used to record, convert digital audio and video, and convert them into streams. In nodejs, there is also FFmpeg, called node-fluent-ffmpeg. node-fluent-ffmpeg is an ffmpeg available on node. ffmpeg must be installed before use. In this article, we mainly share with you the sample code for video transcoding in NodeJS, hoping to help you.
ffmpeg
FFmpeg is a set of open source computer programs that can be used to record, convert digital audio and video, and convert them into streams. Use LGPL or GPL license. It provides a complete solution for recording, converting and streaming audio and video. It contains the very advanced audio/video codec library libavcodec. In order to ensure high portability and codec quality, many codes in libavcodec are developed from scratch.
The following will introduce you to NodeJS for video conversion. coding method.
1. Install FFmpeg (under MAC)
Under MAC, you can directly use the brew command to install: brew install ffmpeg.
After the installation is successful, we can proceed on the command line and use the ffmpeg command to transcode the video. For example, to transcode input.avi into output.ts and set the video bitrate to 640kbps, the commands that need to be executed are as follows:
##
ffmpeg -i input.avi -b:v 640k output.ts
2. Basic usage of node-fluent-ffmpeg module
var ffmpeg = require(‘fluent-ffmpeg'); var command = new ffmpeg(这里可以传入视频文件路径,或者流);
3. Usage Example
var ffmpeg = require('../index'); var command = ffmpeg('testvideo-5m.mpg') // set video bitrate .videoBitrate(1024) // set aspect ratio .aspect('16:9') // set size in percent .size('50%') // set fps .fps(24) // set audio bitrate .audioBitrate('128k') // set audio codec .audioCodec('libmp3lame') // set number of audio channels .audioChannels(2) // set custom option .addOption('-vtag', 'pX') // set output format to force .format('avi') // setup event handlers .on('end', function() { console.log('file has been converted succesfully'); }) .on('error', function(err) { console.log('an error happened: ' + err.message); }) // save to file .save('outtest.avi');
4. What node-fluent-ffmpeg can do
5. Some elements of video transcoding
php implements base64 transcoding into images
Summary of commonly used file transcoding tools
php function code to determine character set and transcode
The above is the detailed content of NodeJS sample code for video transcoding. For more information, please follow other related articles on the PHP Chinese website!

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