Stream videos with on-demand encoding

Usage example

{
  "steps": {
    "import": {
      "robot": "/s3/import",
      "path": "${fields.input}",
      "credentials": "YOUR_AWS_CREDENTIALS",
      "return_file_stubs": true
    },
    "vod": {
      "robot": "/video/ondemand",
      "use": "import",
      "variants": {
        "480p": {
          "preset": "hls/480p",
          "ffmpeg_stack": "{{ stacks.ffmpeg.recommended_version }}"
        },
        "720p": {
          "preset": "hls/720p",
          "ffmpeg_stack": "{{ stacks.ffmpeg.recommended_version }}"
        },
        "1080p": {
          "preset": "hls/1080p",
          "ffmpeg_stack": "{{ stacks.ffmpeg.recommended_version }}"
        }
      }
    },
    "serve": {
      "use": "vod",
      "robot": "/file/serve"
    }
  }
}

Parameters

• output_meta

  Record<string, boolean> | boolean

  Allows you to specify a set of metadata that is more expensive on CPU power to calculate, and thus is disabled by default to keep your Assemblies processing fast.

  For images, you can add "has_transparency": true in this object to extract if the image contains transparent parts and "dominant_colors": true to extract an array of hexadecimal color codes from the image.

  For videos, you can add the "colorspace: true" parameter to extract the colorspace of the output video.

  For audio, you can add "mean_volume": true to get a single value representing the mean average volume of the audio file.

  You can also set this to false to skip metadata extraction and speed up transcoding.

• result

  boolean (default: false)

  Whether the results of this Step should be present in the Assembly Status JSON

• queue

  "batch"

  Setting the queue to 'batch', manually downgrades the priority of jobs for this step to avoid consuming Priority job slots for jobs that don't need zero queue waiting times

• force_accept

  boolean (default: false)
  

    Force a Robot to accept a file type it would have ignored.
  

  By default Robots ignore files they are not familiar with. 🤖/video/encode, for example, will happily ignore input images.

  With the force_accept parameter set to true you can force Robots to accept all files thrown at them. This will typically lead to errors and should only be used for debugging or combatting edge cases.

• use

  string | Array<string> | Array<object> | object

  Specifies which Step(s) to use as input.

  • You can pick any names for Steps except ":original" (reserved for user uploads handled by Transloadit)
  • You can provide several Steps as input with arrays:
    

    {
      "use": [
        ":original",
        "encoded",
        "resized"
      ]
    }
    

  Tip

  That’s likely all you need to know about use, but you can view Advanced use cases.

• variants

  Record<string, object> · required

  Defines the variants the video player can choose from. The keys are the names of the variant as they will appear in the generated playlists and URLs.

• enabled_variants

  string | Array<string>

  Specifies which variants, defined in the variants parameter, are enabled. Non-enabled variants will not be included in the master playlist.

• segment_duration

  string | number (default: 6)

  The duration of each segment in seconds.

• sign_urls_for

  string | number (default: 0)

  When signing URLs is enabled, the URLs in the generated playlist files will be signed. This parameter specifies the duration (in seconds) that the signed URLs will remain valid.

• asset

  string

  Controls which file is generated. For example, if the parameter is unset, a master playlist referencing the variants is generated.

• asset_param_name

  string (default: "asset")

  Specifies from which URL parameter the asset parameter value is taken and which URL parameter to use when generating playlist files.

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