Add echo to an audio file

In this demo, we are going to look at how you can add an echo effect to an audio file. We'll be using custom FFmpeg parameters to do this.

Inside of FFmpeg's af parameter, we can include a variety of filters which alter the audio file when we encode it. For today's demo we'll be leveraging the aecho filter to add a subtle delay effect to our audio.

There are several components to the echo filter that we're using. The first and second value is the input and output gain respectively, which we set to 0.8 and 0.9. The third value is the delay between the original section and the reflections, and the final number is the volume of the reflections.

Step 1:

Handle uploads

We can handle uploads of your users directly.Learn more

joakim_karud-rock_angel.mp3

Audio – 8.9 MB

233s

":original": {
  "robot": "/upload/handle"
}

/upload/handle

This bot receives uploads that your users throw at you from browser or apps, or that you throw at us programmatically

Step 2:

Encode audio

We offer a variety of features to reduce audio size while maintaining quality, as well as add effects like loops or watermarks.Learn more

joakim_karud-rock_angel.mp3

Audio – 3.6 MB

234s

"echo_audio": {
  "use": ":original",
  "robot": "/audio/encode",
  "result": true,
  "ffmpeg": {
    "af": "aecho=0.8:0.9:500:0.3"
  },
  "ffmpeg_stack": "v7",
  "preset": "mp3"
}

/audio/encode

This bot converts audio files into all kinds of formats for you. We provide encoding presets for the most common formats

Step 3:

Export files to Amazon S3

We export to the storage platform of your choice.Learn more

:original

https://demos.transloadit.com/e8/abe2413b1e4a96ac9fe4b849016b32/joakim_karud-rock_angel.mp3

echo_audio

https://demos.transloadit.com/24/445038a9d64015b32bb6f408941db3/joakim_karud-rock_angel.mp3

"exported": {
  "use": [
    "echo_audio",
    ":original"
  ],
  "robot": "/s3/store",
  "credentials": "demo_s3_credentials",
  "url_prefix": "https://demos.transloadit.com/"
}

/s3/store

This bot exports encoding results to Amazon S3

Live Demo. See for yourself

Loading Uppy demo…

This live demo is powered by Uppy, our open source file uploader that you can also use without Transloadit, and tus, our open protocol for resumable file uploads that is making uploading more reliable across the world.

Build this in your own language

<!-- This pulls Uppy from our CDN -->
<!-- For smaller self-hosted bundles, install Uppy and plugins manually: -->
<!-- npm i --save @uppy/core @uppy/dashboard @uppy/remote-sources @uppy/transloadit ... -->
<link
  href="https://releases.transloadit.com/uppy/v3.10.0/uppy.min.css"
  rel="stylesheet"
/>
<button id="browse">Select Files</button>
<script type="module">
  import {
    Uppy,
    Dashboard,
    ImageEditor,
    RemoteSources,
    Transloadit,
  } from 'https://releases.transloadit.com/uppy/v3.10.0/uppy.min.mjs'
  const uppy = new Uppy()
    .use(Transloadit, {
      waitForEncoding: true,
      alwaysRunAssembly: true,
      assemblyOptions: {
        params: {
          // It's often better store encoding instructions in your account
          // and use a `template_id` instead of adding these steps inline
          steps: {
            ':original': {
              robot: '/upload/handle',
            },
            echo_audio: {
              use: ':original',
              robot: '/audio/encode',
              result: true,
              ffmpeg: {
                af: 'aecho=0.8:0.9:500:0.3',
              },
              ffmpeg_stack: 'v7',
              preset: 'mp3',
            },
            exported: {
              use: ['echo_audio', ':original'],
              robot: '/s3/store',
              credentials: 'demo_s3_credentials',
              url_prefix: 'https://demos.transloadit.com/',
            },
          },
        },
      },
    })
    .use(Dashboard, { trigger: '#browse' })
    .use(ImageEditor, { target: Dashboard })
    .use(RemoteSources, {
      companionUrl: 'https://api2.transloadit.com/companion',
    })
    .on('complete', ({ transloadit }) => {
      // Due to `waitForEncoding:true` this is fired after encoding is done.
      // Alternatively, set `waitForEncoding` to `false` and provide a `notify_url`
      console.log(transloadit) // Array of Assembly Statuses
      for (const assembly of transloadit) {
        console.log(assembly.results) // Array of all encoding results
      }
    })
    .on('error', (error) => {
      console.error(error)
    })
</script>

Read docs: Browsers

So many ways to integrate

Transloadit is a service for companies with developers. And there are many ways developers can put Transloadit to good use inside your company to automate media processing.