When a user seeks to a specific position in an on-demand video or audio file after you enable video seeking,the client sends a request that contains the URL of the video or audio file to the server. - Edge Security Acceleration

In on-demand audio and video streaming scenarios, the video processing feature of ESA identifies the nearest preceding keyframe of the playback position to load the video clip that the user wants to play, providing a seamless playback experience.

Before you begin

Your origin server must support HTTP Range requests.
The query string must be set to Retain All.

Add a video processing rule

In the ESA console, choose Websites and click the name of the website you want to manage.
In the left-side navigation pane, choose Rules > Content Optimization Rules.
Click the Video Processing tab. Click Create Rule, and fill in the Rule Name.
In the If Requests Match... area, specify the conditions for matching incoming requests. For more information about how to configure a rule, see Rules.
In the Video Seeking section, click Configure, turn on the Status switch, and configure the parameters.
The following list describes the supported file formats for video seeking and sample URLs:
MP4 files
- Metadata: The metadata of a video file on the origin server must be included in the file header instead of the file tail.
- Parameter: The start parameter specifies the time in seconds and the value can be rounded up to three decimal places. For example, start=1.01 indicates that the video is played from the 1.01th second.
  - If the position specified by the start parameter is not a keyframe, ESA automatically locates the last keyframe before the specified position.
  - If the position specified by the start parameter is not a keyframe, ESA automatically locates the keyframe.
- Custom MP4 parameters:
  - The default value of the start parameter is start, and the default value of the end parameter is end.
  - Custom parameter values can contain only letters, digits, and underscores (_).
- Example:
  domain/video.mp4?start=10: indicates that the video is played from the 10th second.
FLV files
- Metadata: Video files on the origin server must contain metadata.
- Parameter: The start parameter specifies the position. The start parameter supports only values in bytes. Decimals are not supported, and the value is rounded down to the nearest positive integer.
  - FLV Seeking
    - Seek by Time: The unit of the start and end parameters is second. This method navigates you to the video image at the specified point in time, providing a user-friendly experience.
    - Seek by Byte: This method is suitable for precise data or raw video data processing.
      - If the position specified by the start parameter is not a keyframe, ESA automatically locates the last keyframe before the specified position.
      - If the position specified by the start parameter is not a keyframe, ESA automatically locates the keyframe.
- Custom video seeking parameters:
  - The default value of the start parameter is start, and the default value of the end parameter is end.
  - Custom parameter values can contain only letters, digits, and underscores (_).
- Example:
  domain/video.flv?start=10: indicates that the video is played from the 10th byte.

Processing logics of video seeking parameters

Seeking by time is used as an example. The default start and end parameters are used. The following tables describe the processing logics of parameter values in different scenarios:

Requests for MP4 file

start/end values	Example	Processing logic
Invalid values of the `start` and `end` parameters	`start=foo&end=bar`	Ignores video seeking parameters and responds with the complete video.
Valid value of the `start` parameter and invalid value of the `end` parameter	`start=10`	Processes video seeking from `10` to the end of the file.
Invalid value of the `start` parameter and valid value of the `end` parameter	`end=10`	Processes video seeking from `0-10`.
Valid values of the `start` and `end` parameters	`start=0&end=10`	Processes video seeking from `0-10`.
Both the `start` and `end` parameters are set to `0`	`start=0&end=0`	Ignores video seeking parameters and responds with the complete video.
The value of the `start` parameter is greater than the value of the `end` parameter	`start=10&end=0`	Processes video seeking from `10` to the end of the file.
The value of the `start` parameter is equal to the value of the `end` parameter	`start=10&end=10`	Processes video seeking from `10` to the end of the file.
The value of the `start` parameter is greater than the video duration	The value of the `start` parameter is greater than the video duration	Returns response with a HTTP status code `400`.

Requests for FLV file

start/end values	Example	Processing logic
Invalid values of the `start` and `end` parameters	`start=foo&end=bar`	Ignores video seeking parameters and responds with the complete video.
Valid value of the `start` parameter and invalid value of the `end` parameter	`start=10`	Processes video seeking from `10` to the end of the file.
Invalid value of the `start` parameter and valid value of the `end` parameter	`end=10`	Processes video seeking from `0-10`.
Valid values of the `start` and `end` parameters	`start=0&end=10`	Processes video seeking from `0-10`.
Both the `start` and `end` parameters are set to `0`	`start=0&end=0`	Ignores video seeking parameters and responds with the complete video.
The value of the `start` parameter is greater than the value of the `end` parameter	`start=10&end=0`	Processes video seeking from `10` to the end of the file.
The value of the `start` parameter is equal to the value of the `end` parameter	`start=10&end=10`	Processes video seeking from `10` to the end of the file.
The value of the `start` parameter is greater than the video duration	The value of the `start` parameter is greater than the video duration	Returns the complete video.