Axis Communications 241Q user manual Video streams, Video stream types, Motion Jpeg

AXIS 241Q/241S - Video streams 13

Video streams

The AXIS 241Q/241S provides several video stream formats. The type you want to use depends on your requirements and the properties of your network.

The Live View page in AXIS 241Q/241S provides access to Motion JPEG and MPEG-4 video streams, and to single JPEG images. Other applications and clients can also access these video streams/images directly, without going via the Live View page.

Video stream types

Motion JPEG

This format uses standard JPEG still images in the video stream. These images are then displayed and updated at a rate sufficient to create a stream that shows constantly updated motion.

The Motion JPEG stream provides excellent image quality and access to every individual image contained in the stream.

Note that multiple clients accessing Motion JPEG streams can use different image settings.

MPEG-4

This is a video compression standard that makes good use of bandwidth, and which can provide high-quality video streams at less than 1 Mbit/s.

The MPEG-4 standard provides scope for a large range of different coding tools for use by various applications in different situations, and AXIS 241Q/241S provides certain subsets of these tools. These are represented as Video object types, which are selected for use with different viewing clients. The supported video object types are:

•Simple - sets the coding type to H.263

•Advanced Simple - in Axis products, this sets the coding type to MPEG-4 Part 2

AMC (AXIS Media Control) supports both object types, while QuickTime™, for example, requires the Simple object type.

When using MPEG-4 it is also possible to control the bit rate, which in turn allows control of bandwidth usage. CBR (constant bit rate) is used to achieve a specific bit rate by varying the quality of the MPEG-4 stream. When using VBR (variable bit rate), the quality of the video stream is kept as constant as possible, at the cost of a varying bit rate.

Notes:	•	MPEG-4 is licensed technology. AXIS 241Q/241S includes one license for the decoder
	required for viewing in AMC. Installing additional unlicensed copies of this decoder is
	prohibited. To purchase more decoder licenses, contact your Axis reseller.
	•	All clients viewing the MPEG-4 stream must use the same image settings.