899961085usb 3 0 superspeed1 USB IF announces USB audio/video device class

The USB-IF has been none too happy about the various standards that have been pushing other signals than USB down its ports and cables with solutions such as MHL (Mobile High-definition Link) or MYDP (Mobility DisplayPort) being severely frowned upon as they don't conform to the USB standard. It seems like the USB-IF has finally come clean as to why, as it has announced a new USB audio/video device class that will allow for A/V signals to be transported over USB.

The USB-IF has been none too happy about the various standards that have been pushing other signals than USB down its ports and cables with solutions such as MHL (Mobile High-definition Link) or MYDP (Mobility DisplayPort) being severely frowned upon as they don't conform to the USB standard. It seems like the USB-IF has finally come clean as to why, as it has announced a new USB audio/video device class that will allow for A/V signals to be transported over USB.

It's quite a sneaky move by an organization that has been quite harsh towards any solution that has pushed anything but USB data over the USB interface, especially as the USB standard will now start to compete with MHL and MYDP (even though the latter haven't been implemented in any retail hardware we're aware of). The details are scarce on the USB-IF website with regards to the new A/V device class, in fact we could find none beyond the press release. We presume it's relying on USB 3.0, simply because of the bandwidth high definition video requires, but even this isn't mentioned.

By all intents and purposes it appears that the USB A/V device class will be a major competitor to HDMI as a means of displaying video content on larger screens, be it an HDTV or a projector. The USB-IF is suggesting that the standard is ideal for phones and cameras which is quite easy to understand as these devices already have USB connectivity. They're also suggesting it as a means of getting what we presume is uncompressed video from a webcam to a PC for processing before showing it across the internets. The selling point is of course the single interface for data, audio and video, something MHL also offers, at least until you attach the dongle that splits the USB and HDMI signals.

What isn't so clear is if third party chips are needed to be able to push the A/V information from one device to another, something we presume is the case. On top of that there's nary a mention of any interested device partners and without interest from at least a few major industry players, it's likely that this is a standard that won't take off. It's also going to require some kind of adapter which will have to contain at least an additional chip or two if you want to connect a USB A/V enabled device to an HDMI port, as we have a feeling this won't be support on the host side with the help of a simple passive adapter.

The good news is that the USB A/V device class licensing is given on a "reciprocal, zero-royalty basis" although we have a feeling that at least a few companies are going to try to get a slice of the cake here, least not Digital Content Protection LLC, the organization behind the HDCP copy protection standard, as there's no way the USB A/V standard is going to be without content copy protection. In as much as the USB A/V device class sounds like a great idea, there's far too little information currently available to draw any conclusions, but we're going to try to find out more about it to see what is actually being offered here.

Source: USB-IF (pdf link)