In a video on demand scenario, when the playback progress bar is dragged, the client will send a URL request similar to
http://www.aliyun.com/test.flv?start=10to the server. The server will return the data starting from the 10th second to the client. This is called Drag/Drop Playback.
After receiving such a request from a client and the Drag/Drop Playback function is enabled, a CDN node can directly return the data to the client starting from the specified second.
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.
The supported file formats are MP4 and FLV.
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.
startparameter specifies the time in seconds. Decimals are supported to indicate milliseconds. For example,
start=1.01indicates that the start time is 1.01s.
If the current
startis not a key frame, the CDN locates the key frame prior to the time specified by the
http: //domain/video.mp4?start=10requests playing a video from the 10th second.
FLV An origin site video must contain meta information. The
startparameter specifies a byte. If the current
startis not a key frame, the CDN automatically locates the key frame prior to the frame specified by the
http:// domain/video.flv?start=10requests playing a video from the 10th byte.
This function is optional and is disabled by default.
Log on to the
On the left-side navigation pane, click CDN Domain Name List.
Select a domain to enter the management page and find Drag/Drop Playback: