In a video-on-demand scenario, when the playback progress bar is dragged, the end user will send a URL request, such as
http://www.aliyun.com/test.flv?start=10, to the server. The server returns the data from the key frame prior to the10th second to the client (If start=10 is not the key frame).
After receiving such a request from an end user and the Drag/Drop Playback function is enabled, a CDN node can directly return the data from the key frame prior to the10th second (If start=10 is not the key frame) (FLV format) or from the 10th second to the end user.
- To use the Drag/Drop Playback function, an origin site must support Range requests. The origin site must be able to return correct 206 Partial Content for an HTTP request header containing a Range field.
- Two available file format: MP4 and FLV.
- Currently, FLV format only supports the coding formats with the audio format of aac and video format of avc.
|File Format||Meta Information||start Parameter||Example|
|MP4||Meta information of an origin site video must be contained in the file header. A video with its meta information contained in the file tail is not supported.||The start parameter specifies the time in seconds. Decimals are supported to indicate milliseconds. For example, start=1.01 indicates that the start time is 1.01s. If the current start is not a key frame, the CDN locates the key frame prior to the time specified by the start parameter.||The request http: //domain/video.mp4?start=10 playing a video from the 10th second.|
|FLV||An origin site video must contain meta information.||The start parameter specifies a byte. If the current start is not a key frame, the CDN automatically locates the key frame prior to the frame specified by the start parameter.||For http: //domain/video.flv, the request http:// domain/video.flv? start=10 playing a video from the key frame prior to the10th byte( If start=10 is not the position of the key frame) .|
- Go to Domain Namespage, select the domain name, then click Manage.
- Enable the function in .