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HDTV via GNU Radio
NortonDC writes "High Definition TV has been successfully captured in its native data stream from an over the air broadcast by a software defined radio that is Free and open source from the GNU Software Defined Radio project."
HDTV is either 1920x1080 (1080i) or 1280x720 (720p). Where did the 2730x1088 resolution come from? It's obviously wrong (the images are obviously scrunched vertically).
The images on the site are at 2740x1088 resolution, but HDTV at max resolution is 1920x1080. You can tell from looking at the images that they're horizontally stretched, so something weird is going on.
A Linux-friendly HDTV recording solution is definitely needed. Unfortunately, it seems that in order to record HDTV you need a $1300 Analog Input Board.
Can anyone with more knowledge about this project please post a less expensive solution if one exists?
If I am reading it correctly, they used a special radio card under Linux to capture radio waves. Then they ran those waves through a piece of software that could decode them into video, because the waves they tuned into were an HDTV broadcast. The difference here is that they simply record the wave, it's not decoded in hardware. This way they can ues the same card to get FM, AM, HDTV, VHF, UHF, or whatever (in theory). Anyone actually know the answer to this question?
Comment forecast: Bits of genius surrounded by a sea of mediocrity.
Man, I wish the Gnu folks would build their own hardware card rather than the card they are currently using - it's quite expensive.
I'd love to see them put a decent FPGA, an Intersil 50216 4 channel digital downconverter, and a nice 60 Msample/sec 12 bit flash A/D converter on the card - they could do that for a bill of materials of about US$200, and have enough power to do the capture properly.
Before you say "Fine - why don't YOU design it?": I'd love to get more involved in GnuRadio, but I'm afraid of potential conflicts of interest both ways - contaminating GnuRadio with my professional work and possibly exposing my employer to problems with GPL infringment.
Also, is anybody big in the Gnu Radio project going to be at IWCE (International Wireless Convenention and Exposition) March 10 - 14? If so, where? I'm getting in on an exhibitor's badge - maybe I could get pictures?
www.eFax.com are spammers
Bascially the aim is to drastically decrease cost and increase flexibility of radio signal reception and decoding by replacing lots of specialized electronics with software.
Now instead of a very expensive ATSC decoder for your HDTV-Ready TV, you will now have a box with an antenna, maybe a preamp, and a powerful DSP running in software.
The cool part is, you can reprogram or adjust the software as needed to create other capabilities, use other frequencies, or increase performance even after the product is shipped.
I'm sure I drastically oversimplified this, and probably don't realize the full scope of the benifits. Read up on it, use google.
But as applied to HDTV, this is an AMAZING accomplishment. We might soon have open-source HDTV decoding. I for one, would love to have the ability to directly access the native format of the TV signal, stream it to disk, multicast it on my home lan to the living room, whatever. COOL STUFF!
oh yeah, it also gives you TV/HDTV/FM/AM - maybe even satellite radio (but that's probably encrypted).
This is a *universal* radio - you just have to write software to make it do what you want.
Maybe it *will* be illegal in your country.
.au care to comment on the current digital transmissions?
But eventually Supply and Demand will kick in - someone will want to tape "Friends, 2009", so presto! the means will appear. Soon enough you'll be able to buy the equivalent HDTV VCR from China for $120 that "mistakenly" ignores the broadcast flag, a-la DVD zoning.
Pity it means that some other country's tech industry gets the "3) Profit!".
Side note:
Sure won't be worrying about how illegal it is in my country (Australia) for a long while yet.
Is "the switch" happening in 2008? And have we sorted whether we're going for SDTV or HDTV?
Anyone with a set-top DTV box in
Anyone? Anyone? Bueller?
You are in a twisty maze of processor lines, all alike.
There is a lot of hype here.