For those unaware, a USB video class describes a device that's capable of streaming video -- you know, things like webcams
, camcorders, TV tuners and even still-image cameras. For the longest time, you needed to rely on your machine
to do the grunt work associated with encoding video
, but new extensions to the USB video class 1.1 have enabled those very devices to support H.264. In other words, H.264 encoding can now be offloaded to the device itself, and furthermore, the compression provides more bandwidth for additional USB devices. We're told that the H.264 Payload specification is compatible with drivers based upon the USB-IF's UVC 1.0 and 1.1 specifications and relies on proper support of the MJPG and/or Stream Based payload format, and if you're an engineer looking to integrate, the goods you need are stocked away in the source link below.
USB-IF Releases Extensions to USB Video Class 1.1
USB Device Class Definition for Video Devices: H.264 Payload Now Available
BEAVERTON, Ore.--(BUSINESS WIRE)--The USB-IF's Video Work Group completed a supplement to the USB Video Class (UVC) 1.1 that adds the extensions to support H.264. The USB Device Class Definition for Video Devices applies to all devices or functions within composite devices that are used to manipulate video and video-related functionality. This includes devices such as webcams, digital camcorders, analog video converters, analog and digital TV tuners, and still-image cameras that support video streaming.
H.264 encoding enables a host to offload compression to a device such as a webcam. In addition, compression provides more bandwidth for additional USB devices.
Devices supporting H.264 encoding are able to interface with the host using defined controls and video streaming interface(s). The H.264 Payload specification is compatible with drivers based upon the USB-IF's UVC 1.0 and 1.1 specifications and relies on proper support of the MJPG and/or Stream Based payload format. The new controls are defined using standard UVC extension control units. Additional extensions may be developed in the future to enhance control of encoders and decoders for various compression and decompression technologies.
UVC 1.1 from the USB-IF is an open standard and the specification was written with support from USB-IF member companies.
The USB-IF's USB Device Class Definition for Device Class Definition for Video Devices: H.264 Payload is available at http://www.usb.org/developers/devclass_docs#approved.