Pause, then continue MPEG-2 capture + reg hack for 720x480?

[c627627]

This seems like a very informative forum, I hope you can help me.


I understand that it’s best to capture video into avi files > edit them > render them as MPEG2 > make a DVD.

However, if I have 2 pieces of 1 hour videos that require no editing just straight transfer to DVD, is it not easier to simply capture them directly into MPEG-2 > make a DVD? I tried capturing to MPEG-2 using Ulead software and it creates a DVD from this MPEG-2 file without any rendering (which it has to do if the capture is done in AVI instead of MPEG-2.) Am I missing out on quality doing it this way when I don't need editing?


Of all the video capture software I tried, only ATI Multimedia Center appears to allow for an MPEG-2 video capture to be paused, then continued.


1. Is there any other program that allows for MPEG-2 capture into a single file that can be paused, then continued?

2. ATI Multimedia Center appears to only have 640x240 as its highest setting, is there a registry hack to allow for 720x480?

3. How do you compare the quality of same resolution files captured using different software to determine which software is best? Do you take snapshots and compare those?

[guns1inger]

You may or may not be losing quality capturing directly to mpeg-2. If the source is VHS, or VHS passed through DV, then you probably would not notice any difference unless there is high action. If the source was DV or better then you may be losing quality.

There is no difinative way to determine this. Quality is in the eye of the beholder. A friend of mine spent $'000's on a plasma TV because the salemen told him the quality was the best there is. I hate it. I have yet to find a plasma that matches the picture quality of Loewe tube. Moral of the story - what you may find acceptable quality may not be acceptable to me, while what I want may be overkill to you.

Snapshots are probably the least critical way of determing the quality of an encode because of the way mpeg compression works. It is a temporal compression algorythm, compressing across multiple frames. The first frame contains the most information, and is usually the cleanest of the lot. Subsequent frames will contain less information, and may appear softer or blockier. A good encoder will keep the best quality across all frames. One of the symtoms of a poor transcode (or even encode) is pulsing as the frames cycle through.

[c627627]

Thank you for your thoughts. The captures are from DVR > RCA cables > ATI TV Wonder VE.

But one day I will be doing DV captures and you say that even if I do no editing, I would loose quality by directly capturing into MPEG-2 > DVD.

I'm sorry I didn't quite understand the last part, you say naked eyes & ears is the only way to tell the quality difference between different capture sowtware and bewtween
MPEG-2 > DVD
and
AVI > MPEG-2 > DVD?

The recordings in question will be watched in the future on TVs that I can't afford today and that's why I care about quality, but how do I tell the difference.

You say "a good encoder will keep the best quality across all frames." How is this practically determined?

[guns1inger]

I guess what I was saying is that if you are happy, then the quality is enough.

Don't try to future proof your memories. All you can do is produce the best archive with what you have. The TVs of 5 years into the future may be better than what we have now, but so will the cameras. Blu-ray or HD-DVD will allow us to store more data, higher resolutions, and therefore better quality. But being able to store your footage at HD resolutions doesn't matter if you have DV footage recorded at half that.

If you are recording on a DVR, why go through the trouble of capturing through the ATI card ? It is already encoded as mpeg-2. Dump it to DVD-/+RW (whatever is compatible) and edit it on the PC without going through a needless re-encode. Your current method pretty much guarrantees a loss of quality.

Silimarly with DV - using firewire you effectively do a file copy from the camera to the PC - no quality drop. Edit and encode directly to mpeg-2 from your editor, and the loss will be minimal (assuming decent software is used).

There are so many variables in all this - quality of source, quality of editor, quality of cables, quality of encoder, quality of DVD media - there is no simple way to give a qualitative evaluation of your disk. There is very expensive software that will varify it is fully compliant. You can look at the bitrate and make sure it isn't too low, you can buy time base correctors and high-end video enhancers to clean up the signal before sending through to the PC. But ultimately, the best way is to sit down in front of your finished disk and watch it. Look for blurring, macro blocks, colour bleeds, too dark, too light, too muddy, too whatever pisses you off. If you don't fidn these things, it is good. If you do, but you can't change them, you have to learn to live with it.

You don't have George Lucas' resources, so don't expect THX quality

[c627627]

Thank you for your thoughts.

While I understand that you can dump DVR content from certain satellite and retail boxes, the Time Warner Cable DVR boxes are encrypted and last I heard all the attempts to transfer already recorded content (or even to enable Firewire ports on them) were unsuccessful. Please post to say you have heard otherwise...

Thank you for the DV advice. I'll be sure to get a camcorder with fully compatible Firewire port and make sure software is able to receive and encode that content with minimal loss to DVD. (I'm having trouble figuring out just which features are important when comparing camcorders for 'baby growing up' use...)

I like Sony Vegas Video. It's good for AVI capture which I use when transferring content which contains commercials, etc so it needs editing. But if I have a commercial free show, I noticed that Ulead software simply captures it into MPEG-2 than creates a DVD straight up, no hours of additional encoding needed with finished product seeming to be OK, so I was looking for a way to compare them other then, stick the DVD in, remember the quality, stick the other one in, compare from memory...

[FulciLives]

After much playing about I still prefer capture to AVI (either HuffyUV or PICVideo MJPEG) then software MPEG-2 DVD spec conversion (here using CINEMA CRAFT ENCODER).

You simply can't beat the quality this way.

As for DV capture be it pass-through or with something like the Canopus ADVC-100 ... I don't like it. The DV AVI format uses too much compression and the 4:1:1 colorspace thing for NTSC sucks big time.

I'd stick with a PCI capture card with a BT or Philips chipset.

Maybe an ATI with that THEATRE RAGE chipset though I have no real world experience with them.

- John "FulciLives" Coleman

[c627627]

Time to finally answer these questions from 2004:

1. Is there any other program that allows for MPEG-2 capture into a single file that can be paused, then continued?

2. ATI Multimedia Center appears to only have 640x240 as its highest setting, is there a registry hack to allow for 720x480?

3. How do you compare the quality of same resolution files captured using different software to determine which software is best? Do you take snapshots and compare those?

EDIT, three years later :
1. WinDVR appears to also be able to record > pause > continue recording: http://www.artech365.com/winvdr/

2. Depends on which capture card you're using. For best results for NTSC:
Use 704 x 480 to capture SD or HD TV, VCR, analog camcorder.
720 x 480 is used by commercial DVD discs and DV format camcorders.

Later versions of ATI MMC had a 704x480 avi capture setting as the highest resolution setting for .avi captures for some cards, but here's how to get 720x480:

720x480 can only be set if you create a new AVI 704x480 preset and give it an unusual, easy to search for name, then go to Start Menu > Run... > regedit >
Go to
HKEY_CURRENT_USER\Software\ATI Technologies\Multimedia\Features\TV\Video Capture\AVI
then click on the yellow folder underneath.
In the right window, double click on the Width entry > SELECT: Decimal >
Change the Value data: from 704 to 720.

3. Take screen captures but they need to be of the same frame, use VirtualDub http://www.virtualdub.org/
or VirtualDubMod http://sourceforge.net/projects/virtualdubmod/ whicg can also work with MPEg files.