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View Full Version : Newbie extraction question-why change resolution?



acb43
12-23-2002, 02:49 PM
Hello

I am rather new at video extration so please bear with me. I did a few searches and couldnt find the reason why you need to change resources (i am pretty sure this is the resolution) via tivo web before you extract.

Correct me if i am wrong - The way I understand it is to have the video extract come in a format that you can convert into an mpeg. I would be using tmpeg to combine the two files TyTool5 provides to do this.

Now presenty tmpeg will not convert for me I believe becuase I havent done the tivo web step. It reconizes the audio, but says the video is not valid.

Before I do that (change the resolution) I want to ask : what is the impact to my Tivo as far as usability on my TV goes once I make this change?

Is there a negative result possible by doing this? Will there be a change in resolution on my TV?

Am I corrrect as far as why this has to be done?

Again thanks for your patience with a newbie. I just need this spelled out for me before I proceed.

By the way I have a SA Philips HDR212 with Tivonet and an 80 gig drive i put in myself.

Thanks again.

artships
12-23-2002, 03:45 PM
You want a stream extracted from tivo to play on your DVD player, right? Depending on the player, you have to make some changes in the extracted file to get it to match the DVD standards. Some players play 480x480 resolution images and 32kHz sound just fine. Some insist on 720x480 and 48kHz. You can use TMPGEnc to change your tivo stream to DVD-standard, but that takes time - About 6 hours to do one hour-long show (850MHz Athlon). You can change the resoluiton tivo records the video at and thus greatly reduce the time it takes to standardize the tivo stream before you author it and burn it.

what is the impact to my Tivo as far as usability on my TV goes once I make this change?

Tivo records at "Best" for watching live TV. Don't disturb the "Best" settings and you won't notice any difference. Just muck with the "Medium" settings (http://tivo.30below.com/jdouglass/website_bitrates.html), "RecordQualityMedium" of 70, then record things you want to extract at "Medium".

phrend
12-24-2002, 03:46 AM
I would suggest mucking with the Basic quality setting, as I never use it for anything... YMMV

Autodestruct
12-29-2002, 08:13 PM
Do all channels record as 480x480? For example, some PPV shows are widescreen, is the data sent in a different resolution?

Or, by watching the widescreen version, are you actually LOSING resolution (keeping 480x480, yet the black bars on top and bottom are using up horizontal lines)?

Thanks,
-AD

rkimball
12-30-2002, 11:24 PM
You want to record at a resolution that is compatible with DVD format. DVD supports two format for NTSC, 720x480 and 352x480. Tivo SA records different resolutions for the different compression levels. Fortunately, medium format is 352x480 and is mostly DVD compliant. There is a problem with number of pictures in a GOP, but that is another issue.

I am able to record at medium format, extract the stream, and import the video directly into spruceup. The burned DVD plays fine.

The audio is not DVD compliant either. It is 32KHz and mp2. DVD audio for NTSC must be either PCM or AC3, but most players will play mp2. To import the audio into spruceup I need to convert it to 48KHz sampling rate.

FredThompson
12-31-2002, 04:04 AM
You might want to play with DVDPatcher. Go to the links page mentioned in my sig. DVDPatcher is in the DVD section of the A/V links page.

Required resolution will depend on your source type and the standalone player. Would be silly to record a 1910 film at 720x480, for example.

Do transcoding as a last resort unless you want to edit the file.