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DeTer
01-10-2003, 08:21 PM
Thanks to Hi8 for pointing out the fact that my TyDvD's will not be of much use to any of my friends & relatives unless they happen to be lucky enough to have a TyDvD compliant player.
Question 1 is if I transcode to a compliant format like 352x480 will this make my TyDvD's more compatable with all players? I suspect it would.
Question 2 is how do I go about transcoding the video to this format? What program?
Note: I know someone is going to say that this defeats the purpose of DTiVo extraction, but really it doesn't for me as I am a canuck and SA TiVo is not avaible here due to no guide data.Yet:

If someone would be so kind as to give me a process to complete this and note what s/w is required it would be appriciated. I looked at TMPGenc and haven't figured out if it can be done with it, or atleast it doesn't look like it to me.

Thx
DeTer

Note: Reposted this here as I was getting no response in its origional thread.

captain_video
01-10-2003, 09:30 PM
I think its more a question of compatibility with recordable DVDs than it is with TyDVDs in 480X480 resolution. Most older set top DVD players simply will not recognize DVD-R/-RW discs. A lot of them won't even play CD-R discs. Each disc format has different requirements for the wavelength of the laser used to read the disc. Newer players have lasers that are capable of reading recordable DVD discs. Some players produced within the last couple of years have an issue with the 480X480 discs and display the image with a black vertical band on the right 1/3 of the screen. Virtually all late model DVD players introduced in the last 6 months to a year or so all appear to be capable of playing recordable DVD discs, including DVD+R/+RW discs. Some of the cheaper players (i.e. made in China) that have been marketed over the past few years will play almost anything. Apex, Mimtek (?), and various other brands are noted for their abilities to play most formats and are quite inexpensive. I've seen Apex players at Circuit City for under $60. If you want your friends and relatives to be able to play your discs, what better gift than a new DVD player. Before you know it, next Christmas will be right around the corner (it's a bitch getting old because time really does fly).

goldenrod
01-10-2003, 11:42 PM
I have never been able to create compliant DVDs from transcoded 352x480 videos (from Dvds or Dtv streams). By "compliant" i mean it plays in all DVD players that are capable of playing DVD+R/+Rw. They appear those cheap players that play everything you throw at them. I tried all kinds to encoders (TMPGEnc, Cinema Craft, etc) with all kinds of DVD authors (Scenarist, IfoEdit, SpruceUp, Maestro, etc).

My ultimate goal to create complaint DVDs from Dtivo streams and to do that you must transcode. And i transcode at 720x480 ONLY. I use CCE. It's the fastest and produces the best quality. Here is a synopsis of my process:

1. Extract DTivo streams with Tytool.
2. Split with Tytool
3. Create .d2v file from mpeg file with DVD2AVI (to frameserve and crop if video is 16x9)
4. Create Avisynth from .d2v (and use bicubicresize to make 720x480)
5. Transcode with CCE.

You can get more details at www.doom9.org (getting the best out of CCE).


"Note: I know someone is going to say that this defeats the purpose of DTiVo extraction," Deter

I don't think it defeats the purpose. Its the only way to create compliant DVDs.

-GoldenRod

FreydNot
01-11-2003, 03:15 AM
I know your work is done with DTV files, but I have been doing this with SA files for a little while. I have found that I can get much smaller files out of CCE then the SA Tivo records. It seems the SA doesn't do a very good job at on the fly compression.

The example below isn't a very fair compairson since the output file has the commercials edited out (the input file has them left in), but there is still a sizable difference...

For example:
Input video file (split from tyfile): 1,207,272,984 bytes
Input video file resolution: 480x480

Output video file (CCE 3 pass VBR): 561,355,396 bytes
Output video file resolution: 720x480

I have been keeping the overall Q value under 8 or 9 following the doom9 guides.

I'm using avisynth, VirtualDub, and CCE as the major tools. Here is an example of the avisynth script I'm using:



video = mpeg2source("The_Perfect_Match.m2v.d2v")
audio = WAVSource("The_Perfect_Match.wav")
AudioDub(video, audio)

trim(1411,3522) ++ trim(8546,24105) ++ trim(30332,48675) ++ trim(54242,56722)

cnr2(mode=0)
SeparateFields(last)
TemporalSmoother()
LanczosResize(last, 720, 240)
Weave(last)

bato
01-11-2003, 06:13 PM
Originally posted by DeTer
Thanks to Hi8 for pointing out the fact that my TyDvD's will not be of much use to any of my friends & relatives unless they happen to be lucky enough to have a TyDvD compliant player.


Why you don't do a test DVD before going to all this process? I tested one DVDR from a 480x480 and every player tested worked ok, players are Apex, Daewoo, Samsung, Philips and Sony (that's all my family have), the Sony and Philips play DVD+RW also, but not mine (apex build 9/99 original loader upgraded firmware), so I'll be buying another player that can play 480x480, DVD+RW and other things.

FredThompson
01-12-2003, 11:58 AM
The only way you'll get 100% compatability with EVERYTHING is to PRESS a 720x480 fully-compliant DVD. That's just the way it is.

Yes, laser wavelength is important.

Yes, you can transcode a DTivo stream to 720x480. Can't imagine why this would be considered an advantage. Even with CCE, it takes extra time. You're also creating another 50% image data that is pure guesswork, that means you're actually muddying up the stream. DirecTV does a prety good job of creating highly efficient streams.

CVD is a perfectly legal DVD resolution but DVD audio is 48, not 41.1.

Have you made a 100% DVD-compliant test disc and tried it in the various players?

After that, have you tried DVD Patcher?

If that fails, then transcoding might be your only option (although new hardware is a far better way to do it, I think.)

Regarding file size of SA devices, yes, they're cheap junk compared to professional MPEG-2 encoders.

AlphaWolf
01-12-2003, 12:21 PM
why can't you just crop it? aren't there any editors that allow you to crop without re-encoding?

FredThompson
01-12-2003, 12:31 PM
If you crop 480 down to 352 (to get CVD) you're getting rid of 27% of the information and you're changing the aspect ratio. The pixels aren't the same shape between DVD and SVCD. Everything would look fatter. Transcoding for size makes fairly decent educated guesses of how to keep the same display size.