HTTP Request Format for Continuous MJPEG Video Streaming 

Objective

Request an MJPEG stream over HTTP.

Procedure

Issue an HTTP GET request with query parameters to open an (MJPEG) stream from Arecont Vision cameras:

/mjpeg?res=resolution_value&x0=X0&y0=Y0&x1=X1&y1=Y1&quality=quality_value&doublescan=doublescan_value&fps=fps_value&id=id_value

Where the query parameters:

• res is either full or half. full represents full resolution half reduces the stream resolution by a factor of 2 in each direction.
• x0, y0, x1, y1 are the left, top, right and bottom coordinates of the requested image window, respectively. These values cannot exceed the size of the image sensor array for the specific camera and should be divisible by 16, if res=full or 32, if res=half. You can use these values to crop the video to be cropped to a specific size.
• quality is the compression quality of the jpeg image with a range from 1 to 21;
• doublescan specifies whether the camera should delay the image output until a new image is available (doublescan = 0) or if the image request should be serviced by outputting the content of the image buffer that was already output (useful for picture-in-picture display).
• fps specifies the frame rate, an integer between 1 to the camera's maximum frame rate. Ommitting this parameter, providing a value of 0, or providing a value above 16 will result in the maximum frame rate for the camera.

The following example illustrates a request to a camera at 192.168.0.36 for a 1600x1200 video stream with compression quality 12 at the maximum possible frame rate:

/mjpeg?res=half&x0=0&y0=0&x1=1600&y1=1200&quality=12&doublescan=0