
Stream videos with on-demand encoding
🤖/video/ondemand generates HTTP Live Streaming (HLS) playlists and segments on-demand for adaptive and cost-efficient playback.
Usage example
Enable streaming of a video stored on S3 in three variants (480p, 720p, 1080p) with on-demand encoding:
{
"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_metaRecord<string, boolean> | boolean | Array<string>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": truein this object to extract if the image contains transparent parts and"dominant_colors": trueto 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": trueto get a single value representing the mean average volume of the audio file.You can also set this to
falseto skip metadata extraction and speed up transcoding.resultboolean(default:false)Whether the results of this Step should be present in the Assembly Status JSON
queuebatchSetting 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_acceptboolean(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_acceptparameter set totrue, 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.usestring | Array<string> | Array<object> | objectSpecifies 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.- You can pick any names for Steps except
variants— requiredRecord<string, object>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_variantsstring | Array<string>Specifies which variants, defined in the variants parameter, are enabled. Non-enabled variants will not be included in the master playlist.
segment_durationstring | number(default:6)The duration of each segment in seconds.
sign_urls_forstring | 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.
assetstringControls which file is generated. For example, if the parameter is unset, a master playlist referencing the variants is generated.
asset_param_namestring(default:"asset")Specifies from which URL parameter the asset parameter value is taken and which URL parameter to use when generating playlist files.