How-to Trim a Media File
Before you start
This guide assumes that you understand the basics of making a Transcode API request. We recommend completing the Getting Started with Transcoding Media guide first.
Trim a media file
This guide shows you how to use the Media Transcode API to trim the beginning or end off of a media file. Perhaps there are bars and tone at the start or some leading black to be sliced off.
You can picture this operation like the timeline of a non-linear editor, where you want to remove the first few seconds:
The Transcode API uses the segment
parameter that can be applied to an input to make this operation possible.
The segment
parameter has the following properties
segment
start
- The time in seconds to begin transcoding relative to the file start (media before the
start
value is skipped). Fractional seconds are valid, for example10.5
. If this parameter is omitted, the input file begins at the start of the media.
- The time in seconds to begin transcoding relative to the file start (media before the
duration
- The time in seconds to stop transcoding relative to the segment start. Fractional seconds are valid, for example
10.5
. If this parameter is omitted, the media is trimmed from start to end of the media.
- The time in seconds to stop transcoding relative to the segment start. Fractional seconds are valid, for example
Example with a public URL
The following example trims the input
file so that the output
file's first frame is from the 30-second mark of the input.
"inputs": [
{
"source": {
"url": "https://example.com/videos/input.mp4"
},
"segment": {
"start": 30
}
}
],
Example with cloud storage
The same is possible with files located in the storage
object. Read more about Media Input and Output.
"inputs": [
{
"source": {
"ref": "my-storage-id",
"filename": "input.mp4"
},
"segment": {
"start": 30
}
}
],
Example trimming multiple files
It is also possible to trim and stitch at the same time. Read our guide on How to Stitch/Concatenate Multiple Files to see more detail. Here is an example trimming the beginning off of the first file and the end off of the second file in the sequence:
"inputs": [
{
"source": {
"url": "https://example.com/videos/intro.mp4"
},
"segment": {
"start": 30
}
},
{
"source": {
"url": "https://example.com/videos/main_content.mp4"
},
"segment": {
"duration": 300
}
}
],
Updated 2 months ago