Question

对于我的生活，我无法想出翻译：

-i foo.mp3 -filter_complex aformat=channel_layouts=mono,showwavespic=s=4000x1000 -frames:v 1 foo.png

进入fluent-ffmpeg命令。任何人都可以帮助我吗？

我尝试过最基本的命令：

var inputStream = fs.createReadStream('C:/Somewhere/foo.mp3')
var outputStream = fs.createWriteStream('C:/Somehere/foo.png')

var proc = ffmpeg()
     .input(inputStream)
     .complexFilter([
         'showwavespic'
     ])
     .on('error', function(err) {
          console.log('an error happened: ' + err.message);
     })
     .save(outputStream);

我从处理程序中抛出了错误：an error happened: ffmpeg exited with code 1: Cannot find a matching stream for unlabeled input pad 0 on filter Parsed_showwavespic_1

Answer 1

您需要为将生成波形的complexFilter指定一个输入，还需要设置一个我命名为waveform的输出。

这是我的操作方式：（fluent-ffmpeg v2.1.2）

import FFMPEG from 'fluent-ffmpeg';

const ffmpeg = new FFMPEG({
    source: 'path/to/input_file.mp3'
});

ffmpeg
    .complexFilter(
        [
            `[0:a]aformat=channel_layouts=mono,compand=gain=-6,showwavespic=s=4000x1000:colors=#0025ff[waveform]`
        ],
        ['waveform']
    )
    .outputOptions(['-vframes 1'])
    .on('start', () => {
        console.log('FFMPEG started with command:', command);
    })
    .on('progress', () => {
        console.log('progress:', progress);
    })
    .on('error', error => {
        console.log('FFMPEG error:', error);
        reject(error.message);
    })
    .on('end', () => {
        console.log('FFMPEG is done!');
    })
    .saveToFile('path/to/output.png');

Answer 2

该错误告诉您showwavespic过滤器需要输入。

有关简单示例的示例：

var inputStream = fs.createReadStream('C:/Somewhere/foo.mp3')
var outputStream = fs.createWriteStream('C:/Somehere/foo.png')

var proc = ffmpeg()
     .input(inputStream)
     .complexFilter([
         '[0:a]aformat=channel_layouts=mono,showwavespic=s=4000x1000'
     ])
     .outputOptions(['-vframes 1'])
     .on('error', function(err) {
          console.log('an error happened: ' + err.message);
     })
     .save(outputStream);

我想用showwavespic来生成波形数据

2 个答案: