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Transform videos

Media Transformations let you optimize and manipulate videos stored outside of the Cloudflare Stream. Transformed videos and images are served from one of your zones on Cloudflare.

To transform a video or image, you must enable transformations for your zone. If your zone already has Image Transformations enabled, you can also optimize videos with Media Transformations.

Getting started

You can dynamically optimize and generate still images from videos that are stored outside of Cloudflare Stream with Media Transformations.

Cloudflare will automatically cache every transformed video or image on our global network so that you store only the original image at your origin.

To enable transformations on your zone:

  1. Log in to the Cloudflare dashboard ↗ and select your account.
  2. Go to Stream > Transformations.
  3. Locate the specific zone where you want to enable transformations.
  4. Select Enable for zone.

Transform a video by URL

You can convert and resize videos by requesting them via a specially-formatted URL, without writing any code. The URL format is:

https://example.com/cdn-cgi/media/<OPTIONS>/<SOURCE-VIDEO>
  • example.com: Your website or zone on Cloudflare, with Transformations enabled.
  • /cdn-cgi/media/: A prefix that identifies a special path handled by Cloudflare's built-in media transformation service.
  • <OPTIONS>: A comma-separated list of options. Refer to the available options below.
  • <SOURCE-VIDEO>: An absolute path on the origin server or a full URL (starting with https:// or http://) of the original asset to resize.

For example, this URL will source an HD video from an R2 bucket, shorten it, crop and resize it as a square, and remove the audio.

https://example.com/cdn-cgi/media/mode=video,time=5s,duration=5s,width=500,height=500,fit=crop,audio=false/https://pub-8613b7f94d6146408add8fefb52c52e8.r2.dev/aus-mobile-demo.mp4

The result is an MP4 that can be used in an HTML video element without a player library.

Options

mode

Specifies the kind of output to generate.

  • video: Outputs an H.264/AAC optimized MP4 file.
  • frame: Outputs a still image.
  • spritesheet: Outputs a JPEG with multiple frames.

time

Specifies when to start extracting the output in the input file. Depends on mode:

  • When mode is spritesheet or video, specifies the timestamp where the output will start.
  • When mode is frame, specifies the timestamp from which to extract the still image.
  • Formats as a time string, for example: 5s, 2m
  • Acceptable range: 0 – 30s
  • Default: 0

duration

The duration of the output video or spritesheet. Depends on mode:

  • When mode is video, specifies the duration of the output.
  • When mode is spritesheet, specifies the time range from which to select frames.

fit

In combination with width and height, specifies how to resize and crop the output. If the output is resized, it will always resize proportionally so content is not stretched.

  • contain: Respecting aspect ratio, scales a video up or down to be entirely contained within output dimensions.
  • scale-down: Same as contain, but downscales to fit only. Do not upscale.
  • cover: Respecting aspect ratio, scales a video up or down to entirely cover the output dimensions, with a center-weighted crop of the remainder.

height

Specifies maximum height of the output in pixels. Exact behavior depends on fit.

  • Acceptable range: 10-2000 pixels

width

Specifies the maximum width of the image in pixels. Exact behavior depends on fit.

  • Acceptable range: 10-2000 pixels

audio

When mode is video, specifies whether or not to include the source audio in the output.

  • true: Includes source audio.
  • false: Output will be silent.
  • Default: true

format

If mode is frame, specifies the image output format.

  • Acceptable options: jpg, png

Source video requirements

Input video must be less than 40MB. Contact Stream if the input limitation is unacceptable.

Input video should be an MP4 with H.264 encoded video and AAC or MP3 encoded audio. Other formats may work but are untested.

Limitations

Media Transformations are currently in beta. During this period:

  • Transformations are available for all enabled zones free-of-charge.
  • Restricting allowed origins for transformations are coming soon.
  • Outputs from Media Transformations will be cached, but if they must be regenerated, the origin fetch is not cached and may result in subsequent requests to the origin asset.

Pricing

Media Transformations will be free for all customers while in beta.

After that, Media Transforamtions and Image Transformations will use the same subscriptions and usage metrics.

  • Generating a still frame (single image) from a video counts as 1 transformation.
  • Generating an optimized video counts as 1 transformation per second of the output video.
  • Each unique transformation is only billed once per month.
  • All Media and Image Transformations cost $0.50 per 1,000 monthly unique transformation operations, with a free monthly allocation of 5,000.