G450 eTV Video Capture Ideas

[Christrati]

After a couple of weeks, Matrox sent me a patch which fixed my "aliasing" issue (see below for details). Now, the only trouble I'm running into, is capturing with VirtualDub or AVI_IO.

Right now, I'm using YUY2 as the input codec and either Huffy or PICvideo as further compression. I can capture up to 704x480 but I still drop frames during any capture.

The only time I do not drop frames during captures such as TV broadcasts, great quality VHS captures, etc is with the PC-VCR program. But, it uses MPEG2 and I would like to capture straight to AVI for Windows Media conversion (a whole different issue all together).

My big concern are old video tapes I have, they are not of the greatest quality, but with either the PC-VCR or Virtualdub, etc, I drop tons of frames! I've read posts similar to this and many people suggest a Sigma SCC, etc, but will this help? If it is a Macrovision error, then will the SCC actually help those old tapes?

Any suggestions for a good capture? BTW, I have the same problems with the G200 capture card, but I have not used the Vidtools 1.52 w/ macrovision patch.

Chris

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Marvel G450 eTV capture problem:

This was a simple fix, basically Matrox sent me a registry key which enabled "interlaced" MPEG2 capture. It seems by default the PC-VCR does not capture "interlaced video" and would cause aliasing. Well, the truth is it would encode the wrong field thus causing aliasing. If anyone else is having trouble, you can email me and I'll send you the registry key.



[This message has been edited by Christrati (edited 20 May 2001).]

[Dr Mordrid]

Actually the eTV's MPEG-2 video is captured as progressive scan. Check it with BitRateView and you should see this listed in the file properties.

If the old tapes don't have Macrovision copy protection then the drops & artifacts are likely caused by deteriorated synch and colorburst signals in the recordings. This is common in old tapes.

To alleviate the situation with old tapes you need hardware to restore the synch and colorburst to proper levels.

I do this with an Elite Video BVP-4+, which is a not too cheap solution at $750. The SIMA SCC is cheaper at about $130 and will restore synch and colorburst levels to normal as well. Using either helps capturing off old tapes enormously. Still, if the tape itself has suffered physical damage there is no coming back from that.

The BVP-4+ or SCC can also be very handy when put between the video cards output and a VHS deck when printing to video. This way you KNOW the signal to the VHS deck is clean, strong and will be recorded with the highest fildelity possible with that deck.

The difference between the SCC and the BVP-4+ (other than price(G)) is that the BVP-4+ has other very advanced signal processing capabilities not found in too many sub-kilobuck devices. With these it can restore black levels and full whites as well as perform numerous special effects and rebuilding color satuation.

Dr. Mordrid

[Christrati]

Dr. Mordrid,

Thanks for the info, do you think if Macrovision is disabled it will help with those old tapes?

They are pretty crappy, very jumpy, noise, etc.

As for the eTV captures, I haven't used BitRateView, but with VideoStudio, it shows the file properties as Field B. I'll download BitRateView (hopefully freeware) and see what it says.

Chris

[Dr Mordrid]

Here's the BRV home page;

http://tecoltd.com/bitratev.htm

Don't just download BV.EXE. Get BITRATE.EXE too. It's an updated executable.

Dr. Mordrid

[Christrati]

Here is the info from the files I encoded:

(Straight from PC-VCR)
Num. of picture read: 1801
Stream type: MPEG-2 MP@ML CBR
Resolution: 704*480
Aspect ratio: 4:3 Generic
Framerate: 29.97
Nom. bitrate: 12800000 Bit/Sec
VBV buffer size: 112
Constrained param. flag: No
Chroma format: 4:2:0
DCT precision: 10
Pic. structure: Frame
Field topfirst: Yes
DCT type: Field
Quantscale: Linear
Scan type: ZigZag
Frame type: Interlaced
Notes:

(Coversion using Ulead VideoStudio 5 DVD-plugin)
Num. of picture read: 1801
Stream type: MPEG-2 MP@ML VBR
Resolution: 704*480
Aspect ratio: 4:3 Generic
Framerate: 29.97
Nom. bitrate: 4956400 Bit/Sec
VBV buffer size: 112
Constrained param. flag: No
Chroma format: 4:2:0
DCT precision: 8
Pic. structure: Frame
Field topfirst: Yes
DCT type: Field
Quantscale: Linear
Scan type: ZigZag
Frame type: Interlaced
Notes:

This is with the patch provided by Matrox. Any further info on capturing my old videos will be appreciated! I still loose frames, but at least I can record live broadcasts, etc.

Chris

[Christrati]

Dr Mordrid,

I've downloaded the utility and analyzed some of my clips. Later today I will post the information it provides, but it states the encoding as Field and interlaced (of course I'm using a registry key supplied by Matrox Tech Support enabling interlaced capture). I will post the info later as I'm currently converting some newly captured clips to miniDVD.

Chris

[SatMan]

Re-the registry patch for solving the jagged edges issue dicussed by the original poster of this thread.
Is it available for download anywhere?
If it is a simple on line regedit value change can it be posted in plain text here?
Thanks

[Christrati]

No big problem, here's the registry entry I enter which fixes the aliasing issue:
(Remember to backup your registry--this is for advanced users only.)

REGEDIT4

[HKEY_CURRENT_USER\Software\Ligos\GoMotion Interlaced]
"FieldOrder"=dword:00000000
"Interlaced"=dword:00000001

Chris