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Wireless HDMI Prototype Announced
legoburner writes "Tzero Technologies and Analog Devices announced that they have created a wireless HDMI interface for HDTVs, next-gen DVD players, and set-top boxes. The backbone for the technology is ultrawideband, also used as a future replacement for wired USB. The Analog Device compresses data with the [lossy] JPEG2000 video codec, which is then packetized and encrypted, and transmitted via the Tzero MAC and PHY chip."
JPEG2000 has both lossless and lossy modes.
Did I miss something in the article indicating which they were using?
If you get your HD from digi cable or dish (which 90% of HDTV owners do), then the signal has already been compressed in MPEG2 or MPEG4 on it's way down the pipe.
Then again, this thing is just adding in another compress/decompress cycle - not good IMO.
Remember - JPEG is a compression standard. By definition it is a "lossy" comnpression. Picture quality loss remains TBD. Need to read the details.
This is a first generation UWB wireless interconnect. When the concept of UWB mas marketed around a few years ago, the claim was that it would be a low power RF communication method.
Low power at the antenna, yes, at the power supply, no.
However, the power consumed for all the signal processing in the receiver & transmitter is pretty huge. The channel bandwidth is 250MHz and uses OFDM modulation. The implication is gobs of juice to run an ADC to deal with that high bandwidth, and "must have" DSP to do all the signal processing. (OFDM requires rather fancy signal processing, which can not be implemented using a lower power analog method.)
The net result - The "low power of UWB" may be true at the antenna, but the electronics require huge amount of juice to get the job done. Consequently battery powered applications are no-go. Now you got this fancy new wireless standard and a limited use for it, with all the applications needing to be plugged into the wall.
IMHO? Poke a hole in the drywall at the floor, run the cables up thru the wall and into the display. You have to do that for the power cord anyhow, so why not? It's not like you are going to be moving the silly thing much after you install it!
UWB won't see the widespread use of WiFi or Bluetooth.
www.effectiveelectrons.com "chips that work" Analog, RF, Mixed Signal
So sayeth their presentation anyhow.
http://www.tzerotech.com/site/demo/
JPEG and JPEG2000 are very different lossy image compression algorithms. JPEG uses discrete cosine transforms, whereas JPEG2000 uses wavelet transforms, which are much better at representing non-periodic data, like you'd see in motion video.
If the consumer-electronics people weren't so hung up on proprietary interfaces, consumer electronics could just use 100baseT for everything. More bandwidth than some UWB thing, can be extended to cover just about any house, cables are cheap, and interference isn't a problem. You can get a whole 100baseT/TCP/IP node in the RJ45 connector now, so low data rate sources like audio devices could play cheaply. Power over Ethernet could power some of the lesser boxes, like cable modems.
That "30 meter UWB" link will turn out to be a huge pain. It probably won't work through walls especially ones with metal studs, so inter-room links in houses will fail. Even across a large classroom (an obvious application), there might be problems. The DRM probably won't allow multipoint distribution, so you can only have one monitor per Blu-Ray player, but that's another issue.
I would not consider myself an expert, but this is my field, so let me give everyone a REALLY quick lesson in 1) JPEG2000 and 2) "lossy" video compression.
JPEG2000 is an advanced set of tools for video compression. It is used at the highest levels of distribution, and has been proposed for consumer use as is the case here. For more on JPEG2000 a decent primer is here.
If you are watching content at home, it already has gone through a "lossy" compression scheme. Whether it is DTH satellite MPEG2 or MPEG4), cable (MPEG2/NTSC - yes NTSC is a lossy compression scheme), or terrestrial (MPEG2 ATSC or NTSC), DVD (MPEG2), or even LaserDisc (NTSC), your content has gone through a lossy scheme.
Remember, Google is your friend, and although not perfect, wikipedia can answer many questions. For more on video compression here is a nice little presentation.
The short story is everyone shouldn't get real upset about JPEG2000 and it being lossy. Cheers.
It does claim lossless JPEG2000. The slashdot post is incorrect.
-=Lothsahn=-
For $5, you can drop # 9.
http://www.myopenx.com/
Hey guys don't you know that every "HD" signal you currently see is compressed? Infact it's even compressed with a lossy compression when its recorded to tape from the HD camera. Unless you're taking an SDI out cable directly into a Hard Disk Recording system and hardly anyone does that. Why is all HD compressed? 1 1080i uncompressed stream runs 165MB/sec ....do the math ;) and even though its compressed it looks pletty good. One of the widest formats used with cameras and editing/storing is the DVCPRO HD Codec, Panasonic who is the current leader in HD cameras uses it with their VariCam setups. Sony uses a mixture of formats which in my opinion has hurt their market share...what else is new.
At anyrate everything is captured edited and outputted using compressed HD. Then its recompressed to be broadcasted either using MPEG-2, MPEG-4 or .H264, most people suffer quality loss from dropped packets durring transmission rather than compression artifacts. JPEG2000 has a less noticable compression than the other formats it actually uses a higher data rate than the other formats (which is good) however I'm surprised they didn't go with a .H264 standard which may be better because you can get similar quality with a smaller data rate.
This may confirm apple rumors about a "wireless video Jobby" similar to what Aiport Express is for audio. Since they're already pushing tv shows and it's known they are wanting to start pushing movies. Granted 2 generations of compression/decompression isn't great but you're really not going to notice it especially at 1080i.
and remember HD-DVD and Blue-Ray are also using compressed HD video formats wether it be WindowsMedia, .H264 or MPEG2 so stop all your Compression whining very few people have seen pure uncompressed HD....well except maybe at the movie theater...but thats film and it looses a generation going to analog....you still have film grain, dust and scratches. :)
looking forward to what apple is going to do with it all.