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Uncompressed TV Video Over USB 2.0 from ATI
An anonymous reader writes "Ever wanted to watch TV on your notebook computer? Well, you used to be stuck with an external TV tuner that will usually compress the video so much to squeeze it down the USB interface, that it's not worth watching. But the new ATI TV Wonder manages to push uncompressed video down the USB 2.0 interface, producing superb image quality. It also comes with ATI's suite of multimedia applications and utilities. The reviewer reckons it's a great unit, although a little bit on the expensive side."
*Sighs for some dupe checking*
I watch tv on my laptop already using the wireless connection to my dekstop using it's PVR-250 mpeg2 card.
/dev/video1 &
ssh desktop nc -l -p 7000
nc desktop 7000 | mplayer -framedrop &
ssh desktop ptune-ui.pl
And whala! I watch TV on my laptop via 802.11g wireless card. (I use prism54 based cards.. very easy to setup on newer kernels)
Of course you can use video lan server to do it if you want to get fancy, but I like netcat and to run the channel changing gui perl script thru X tunneling over ssh.
Betcha you Windows guys didn't know I could build a video streamer using 2 lines in a Bash shell, did you? And people say Linux is sooo hard.
But if you want to get fancy check out VLS (VLC is a popular media player in Windows already, too. VLS is the server half and it only runs on Unix-style boxes)
Use that and buy a cheapo Bttv based card or a nice mpeg2 encoder like mine. All the video you need on your palm pilot or laptop, or seperate desktop computer you'd ever want. And if you have one of those faast DSL or cable lines you can even stream tv or dvd's or whatever to yourself at work.
Easy.
VideoLAN
"Broadcast" from your server with TV tuner as source, watch anywhere on your LAN.
It works well. VideoLAN+server full of TV and DVD rips = my very own Video on Demand system that blows the doors off of what Comcast offers.
I don't need no instructions to know how to rock!!!!
The EyeTV boxes do in fact have TV tuners. The EyeTV 200 is a FireWire based PVR-like device for Mac. (It's about $300, though).
Broadcasters are only obligated to switch to ATSC when 80% of the local population are actually able to obtain ATSC signals. That means, that 80% of the local population will actually need HDTV tuners and monitors in place.
That is a LONG way off for most of the US.
If someone says he and his monkey have nothing to hide, they almost certainly do.
There's been some pretty positive results with the Sasem device. See this thread in the AVS Forums (pretty much THE place for HomeTheatre knowledge) if you're interested in grabbing one. Be forewarned hoever, the AVS forums are as much a timesink as /.
t hreadid=373490&highlight=sasem/
http://www.avsforum.com/avs-vb/showthread.php?s=&
JA
Maybe it's not 24-bit color.
"Full resolution" is meaningless when you talk about an analog signal, too.
ATi's TV Wonders in the past have considered 320x240 to be "full resolution", and anything higher was scaled up (video captures) or interpolated (still captures) from that.
I don't know if it natively captures any higher now, but 320x240x16 at 24 fps isn't unreasonable.
ATi used to really shine at all this cross-media stuff, nowadays they're teh suck. TV-Out quality on my 9800 is absolutely awful compared to a cheap GeForce 5200, for instance.
I don't need no instructions to know how to rock!!!!
My guess is comcast does not care. Time Warner will do a Roadrunner only install, but they charge you THE SAME price as if you paid for both the TV ands Cable Modem. So really, to them, they are getting the same amount of money.
Gorkman
The number I've read is 85%, and "able to obtain" or market penetration is subject to interpretation. Many people count existing cable and DBS subscribers as part of the ATSC group, leaving OTA NTSC viewers in a small minority in most areas. The FCC wants to get this show on the road, so don't bet on NTSC living forever.
Mea navis aericumbens anguillis abundat
... want uncompressed signal so they can do more than dumb stuff like record TV and play it back.
Some people, like myself, want uncompressed video so we can load it into a editor, chop out all the commercials, and encode it with DivX or Ogg Theora or something else. Or write it out to a DVD. Now they don't have to Fast Forward through the commercials.
Here's another thing some people like to do. Hook up their VCR to the capture card, put in some old VHS tapes, and start recording. Then they can edit it, arrange the clips, and write it back to a DVD so it doesn't get degraded. The Macintosh is amazingly good at this sort of thing, particularly with DV cameras (if you don't have one, use a Formac Studio TVR).
Anyway, you can't do any of these things with MPEG, because most editors don't do MPEG editing. Final Cut Pro and Premiere don't even do it (I've tried with v3 and v6 respectively). Why? Because it's lossy!
Uncompressed, non-lossy video is good, particularly in open formats. Just because it doesn't suit your application doesn't make it any less cool.
A) NTSC is 29.97 FPS, PAL is 25. B) YUY2 video (essentially, full quality digital component video) is 16 bits per pixel. So take a 720x480 image 30 times per second at 16 bits per pixel and you get about 20 megabytes per second. USB2.0 supports up to 480mbits per second, or 60 megabytes. While it is more CPU dependent than firewire, it DOES have the bandwidth. I work for Avid, and our $25,000 Adrenaline box connects to the PC via firewire and is by no means limited by the fact that the firewire bus is only 50 megabytes per second. It captures uncompressed with impeccable reliability. USB 2 isn't optimal for a true pro video editing setup, but at the very least it DOES support the bitrate full quality NTSC video requires.
I've been the (mostly) happy user of a Pinnacle PCTV Deluxe. It is an USB2 external tv tuner that supports mpeg compression in hardware at bitrates up to 15MB/s
....
DVD's is about 6MB/s so i think that 15 should be enough for most
The only problem with compression and decompression is the timelag when changin channels
They forgot to mention this device as well. A coworker has it, he says it's fantastic in terms of quality, features, and software.
--Dan
Fellow Mac user to Mac user(powerbook even), don't hold your breath. ATI doesn't make its Mac branded cards(Apple does) so I don't think they have a lot invested in making Mac compatible hardware and drivers.
Just my thoughts, nothing more nothing less.
I believe Firewire was chosen as the dvd standard interconnect some 2 years ago. All the dvd manufacturers are busy meeting that standard. See the Audio Revolution article.
something like this?
They mean uncompressed over the USB2 wire. Once it reaches the computer you can choose a format to encode to if you want to record it.
Older USB1 tuners would compress the stream to make it fit in to USB1's bandwidth (or lack thereof), usually with a low quality MPEG1. If you wanted it in a different format, you then had to transcode, making the quality even worse.
The USB2 tuners deliver the raw signal from the ADCs to the PC tuner software. What is done with it from there is the user's choice. You can record the stream uncompressed (at least in the last version of ATIs tuner software I used.)
I used to get high on life, but I developed a tolerance. Now I need something stronger.
Whala!?
peut-être vous avez voulu écrire "voilà"
It doesn't have a comb, but I use the ADSTech Pyro A/V Link to convert NTSC (it works with PAL too) to standard DV. You only need a comb filter when you're dealing with composite or less, anyway.
How did you come to the conclusion that your card stretches 640 pixels to 720? If you went solely on the width of the frame on your computer screen, then it's likely that your card really does capture at 720 pixels. Those 720 pixels are actually supposed to be horizontally thinner on a real NTSC display than they are when you display the video without any aspect ratio correction. For example, if you have an NTSC source with a circle in the center that appears to be a perfect circle on an NTSC set, when you capture it on the PC and display it unmodified, the circle WILL look horizontally fat. However, take that same source, after capturing, and play it back out on a device that supports 720x480 output to NTSC (nVidia cards do this), and it will look correct again.
If you're expecting perfect circles to stay perfect at 720 pixels capture, that will NEVER happen, because there simply isn't any more horizontal data to capture. If you want your final encoded file to have the correct aspect when played back on a square-pixel PC display, then resize it to 640x480 during the encode (NEVER resize vertically though, you'll mess up the fields). I personally recommend leaving the video at 720x480 and using a player such as DScaler to correct the aspect ratio - that way, you retain as much of the original resolution as possible. I find that encoding to Divx at a sufficient bitrate to fill a full CD-R with 30 minutes of video to give very high quality results (I do almost no processing during my encodes - only to clean up the existing video, never to delace it).
FC Closer