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bloopletech | 12 years ago

Back of the envelope calculation:

(1920 * 1080 * 3 * 60) / 1024.0 / 1024.0 => 355.96 MB/s

300mbps wireless n:

300 / 8.0 => 37.5 MB/s

Given that the whole point of HDMI is image quality, how are they going to shove 355MB/s through a 37.5MB/s link without lowering the quality hugely?

It all seems rather pointless to have a large, high quality display and content, and force it through a small link.

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Renaud|12 years ago

BlueRay in 1080p is encoded at most at 35Mbits/s. You only need a decoder on the other side and stream the video data to be decoded by the remote device.

There are a few protocols out there that manage to send high-performance video across remote devices without requiring lots of bandwith: RemoteFx is an extension of Window's RDP for instance; Citrix has stuff like HDX-3D Pro, etc.

You certainly do not need to send every pixel through.

martin-adams|12 years ago

Yet don't forget your satellite provider has achieved the same to put HD content over a satellite and through an HDMI link.

Sky HD in the UK probably encodes each channel at around 12-18 MB/s.

The key is in the compression and latency for real time applications.

rsanders|12 years ago

From what 355.96 MB/s source are you receiving that video? For some very common use cases, it's either HDTV channels or Blu-Ray, both of which give you compressed bitstreams of less than 50 Mbps. 802.11n can handle that with ease. Granted that recompressing content in real-time doesn't do great things for the quality, but it's good enough. The point of HDMI is that it's a standard connector. Nobody's going to buy a VGA dongle these days.

OnLive and Sony/Gaikai are streaming game A/V over the public Internet, and Amazon has a new platform to do it for arbitrary Windows apps. Again, a decent in-home wireless network is a far superior medium and should have no problem.

lambda|12 years ago

This is compressing the video using either H.264 or WebM (it's a bit unclear; they include both x264 and WebM logos in their "open source software used"); it's similar to Apple's AirPlay mirroring or Google's Chromecast. Unlike those, however, it's not tied into a single company's ecosystem.

webjprgm|12 years ago

Also remember that most of the time you have two hops on your wifi network: PC -> router -> TV. (Newer wifi cards can skip the router if the software on both sides supports it.)