HDTV Recording quality

[TV Scheduler]

I'm sure that many will say,'nay', but I have found that HDTV need not be recorded at full HDTV quality. When a HDTV signal is converted down and recorded using Svideo it looks great when played back in a player with a zoom feature designed to bring it back to full size.

I have three HDTV receivers. One is the ATI HDTV wonder. I used this recorder as the baseline. I've used the two other recorders to make recordings using Svideo and Hauppauge mpg encoders. When I compared the recordings I can only guess which recording is at true HDTV quality.

There are a few cable boxes out there with firewire connections. I haven't tried any yet. It appears that the channels can be changed and the output recorded using firewire. This sounds great and I may drop DirecTV and give it a try.

BUT.....

Right now I get recordings at 2Gigs per hour that I can't tell from the ones at 7 Gigs per hour. I also have intermittent problems with my recordings at HDTV qualities. They had become unwatchable but I reformatted the drive I use for HDTV quality recordings and the problems spots are now brief enough to ignore.

I require at least 3 recorders because of how the broadcasters choose to schedule their content. I'm concerned that one computer may not be able to handle three or four HDTV recordings at full HDTV quality while doing other things.


In my life I have learned that it often takes 10 times as much to get the last 10% as it did to get the first 90%.This may be one of those cases where getting that last bit of quality isn't worth it's current cost.

Bob

[Baylo]

I agree - I have advocated recording the S-video output from HD channels in a couple of posts here. I think it all comes down to the quality of your display and viewing distance. I'm using a 30" Sony CRT which does look very good when displaying HD. But the fact is, despite a native display for 1080i content, I'm sure there just physically are not 1920x1080 phosphor dots on the screen. Couple that with a viewing distance that's far enough back and the zoomed in display is good enough. I can still tell the difference from true HD, but it's good enough.

Mark

[Rich A]

It's all in the "source". Any re-encoding, transcoding etc. is going to look great if you use most any kind of "good" digital source. As is true with any mpeg building .. the single most important factor is the original source.

You know .. GIGO. If you had a plain old uncompressed *.avi at 1920x1088 you'd also end up with incredible final video after encoding it.

I would like to know however if you have tried using the actual ATI *.VCR for your source in it's native form? ATI has it VERY weird. The saved *.vcr file is usually split up and is also not subject to easy re-combining. One of the reasons I do have and prefer that fancy editor I'm always promoting is that it can edit 1920x1088 transport streams and even convert ts streams to program streams. But as is the case with both the ATI transport streams and the *.dvr-ms (MCE 2005 streams), they are difficult if not impossible to work with.

I've tried all the available stuff for trancoding or editing and/or changing the MS *.dvr-ms files and so far have had no joy with any.

I think you are simply encoding the play back of the HD no? This to me would mean way too much time involved. I'm trying to find a way to record the native transport stream (which is easy to do) and then convert that stream by either transcoding (fast) or re-encoding (slow) to an mpeg dvd-proper asset for dvd authoring. Would love to compare notes here.

[Baylo]

Hi Rich,

You're absolutely right about the source quality being all important.

I can't comment on the ATI stuff, as I don't use it. My cable box simultaneously outputs the HD channels in a down-converted letter-boxed format over the S-Video cable and that's what I record. But the quality of the source means that even the down-converted output can be very very good. In fact, I prefer to record this source rather than the regular standard def transmission. For example, I'll record the down-converted transmission of Lost on ABC's HD channel rather than the SD transmission of Lost on the regular ABC channel. For me, the benefit of widescreen presentation more than offsets any minor decrease in picture quality.

Now, I'd still rather have HD recording capability - don't get me wrong about that - but this is good for now.

Mark

[TV Scheduler]

Ok guys, just to be clear. I can tell a down-converted recording of an HD broadcast from a digital SD broadcast in letterbox format.

The converting is done by the STB. One of my STBs is a Motorola and the other is a Toshiba. I simply set the output of the STB to 480p and record from the Svideo output. This means that BTV can make the recordings but I don't know if they offer the right zoom feature for the playback.



I tried all of ATIs software and for a time my little recorder using Microsoft's software had it all beat. I've done something along the way that has created a problem. I can remember playing an HD recording while making 4 recordings using Hauppauge encoders and making a fifth recording at HD quality. I try lots of things and sooner or later I break something. I'm at the point of having to flush this setup and reinstall everything.


I don't transcode or re-encode. I watch and delete recordings. If it's a good story, after several months, I'll watch it a second time but I've found that keeping a copy is pointless after the second viewing.

Bob