Is this the MPEG2 quality I should expect??

[InTheCave]

Relative newbie to capture, but before I get torched, I've searched and searched, read the guides at lordsmurf's site and those here looking for a discussion of expected image quality/degradation on capturing direct via MPEG2 with the AIW 128M cards, and haven't really found a post that addresses black level or a washed out appearance I'm seeing using the MPEG2 capture.

I'm just wondering if my expectations are above what this card can do. I captured a segment of a program featuring a space effects shot (deep black) and was disappointed by the washed out image that's present when compared side-by-side to the source image paused in the TV window. This is present throughout, but is extremely apparent when comparing the black.

Here are urls for two images: first is a screen grab using the MMC capture utility of the input image.
http://f1.pg.photos.yahoo.com/ph/___thebat___/detail?.dir=/a3d9&.dnm=29a8.jpg

The second is a screen grab of the paused playback (using MMC File Player) of a captured file from the same live source.
http://f1.pg.photos.yahoo.com/ph/___thebat___/detail?.dir=/a3d9&.dnm=5898.jpg

Capture was done on modified DVD High setting MPEG2 720x480, I frames only, 8 MB/sec max & target, 70 motion, 256k 48kHz 16 bit audio, no VIDEOSOAP. The video source is an UltimateTV PVR (Microsoft's Tivo product) capture of DirecTV run thru S-video into the AIW. I have tried various settings within the MPEG2 High DVD range, without much noticeable difference to the washed out effect. Capture was done with the Network card disabled, yadda yadda....

Gear is a Compaq W6000 workstation 1.7GHz, 1Gb PC800 RAM, AIW 9700Pro, captured to a secondary 160GB WD ATA133 drive which is on a separate IDE PCI controller card, main hd (OS & Programs) is 40GB WD ATA100, Win XP, all drivers, etc. are up to date. This is a freshly loaded machine only just loaded the OS and not much else on it yet.

I do get a deeper black when capturing directly to AVI, and am reading through all the hoops I'd have to jump though and codecs to use, VirtualDub, converting to MPEG2, etc.... to properly get to the point where I think I want to be. It just seems that in my reading this path is for the hardcore image quality folks, and before I count myself amongst them, I want to be sure I'm not simply doing something wrong with the MPEG2 capture.

So the question is, given my screen captures above, is that as good as it gets with MPEG2 direct capture, or do I really need to keep sifting through settings guides to fine tune? Am I perhaps not comparing apples to apples by playing back the captured file in one window and viewing the TV signal in another side by side? I have not tried authoring/burning the captured mpg to DVD and comparing the images on my TV yet.

I guess it's just that I'm just a little surprised after reading all the outstanding reviews the AIW cards get that the quality I'm seeing is as good as it gets. If that's true I guess I just keep reading on VirtualDub and AVI capture/conversion and skip the MPEG2 direct if I'm looking for a nice sharp image, right?

Please advise, and thanks in advance for being gentle...

[substream]

Bump.

Im having the same issue with my aiw 9200. Washed out, loss of brightness, square patterns showing on the darker colors.

[Gazorgan]

One test is to do a capture in HUFFYUV and see if the problem persists. Capturing to MPEG2 means the encoder has to make decision in realtime about quality, without dropping any frames. No filters and a CBR encode.

A TV signal tends to be a noisey thing. Even if you can't see it, it's much noiser than a DVD signal. As such it steals bitrate. That means you need more bitrate for an unfiltered TV signal.

Besides, screen shots don't count. The real question is how does it look on your TV?

[InTheCave]

Well, that was in essence my question as to if I was making a fair comparison.

I did try capturing via Huffyuv and the picture quality does look much better, but of course I have to run it through all the filters etc.... again, I get it that my output will be better capturing to huffyuv/avi - but my real question centered on the expected quality of capturing to mpeg2 directly. I've upped the bitrate as high as possible, and still don't see any increase in quality, and don't get why.

I'm not sure I agree with your statement that "screen shots don't count" as shouldn't I expect to be able to compare quality of a capture on my monitor? What if I was was only intending to view these captures from my computer and not via my tv? Shouldn't the captured play back look as good as the source viewed live on the same monitor?

I'm really still concerned that I'm actually doing this right and what I've got *is* as good as it gets--especially when I read lordsmurf's site which basically states that mpg2 capture should be fine unless I'm doing digital editing.

Questions questions... anyone with answers?

[lordsmurf]

It looks fine. The problem is you are viewing on a computer monitor with 0-255 colorspace, but your tv has 16-235 and that computer dark gray WILL turn black on tv.

Burn a test to DVD-RW/+RW and see for yourself.

Motion is important, so still images are useless for quality examples. What look bad in one frame may look perfect in the other 28, so you'll get a second of good quality anyway. Noise changes too from frame to frame.

Some of the minor blockiness or amoeba effects also disappear on a tv set, but are crystal clear on a compuer monitor.

Plus interlaced can never be viewed perfectly on computer monitor. Must use tv.

[Manokat]

I am sure we all know that MPEG2 is an interpolated, resampled and compressed video. Washed out color (NTSC burn) and pixelization will always be introduced along the process. The intensity of their ocurrances will be more obvious in direct MPEG2 capture.
Increasing the bit rate as well as the motion search level (to 100) help reducing them.

Since most NTSC TV's are set to have black level of 0 IRE instead of the standard 7.5, those gray areas will appear to be black.

But, really you can not expect more satisfying result with direct MPEG2 via software encoding than a hardware dedicated encoder.

[neomaine]

inthecave,

I capture from DISH and see, to some extent. the same thing you are. I believe part of your problem is that you are re-encoding the already MPEG2 encoded stream.

Thus, you will find that the re-encoding will 'interpret' some of the MPEG2 distortions (color issues, pixelation/block noise) already present in the capture and 'highlight' them for you.

You have a few choices:

1 - Capture direct to MPEG2 with your AIW as you are now.
2 - No. 1 + add some videosoap to help clean up (realtime).
3 - Cauture to avi and then pass through another MPEG2 encoder like TMPGenc or CCE and let them take their time on the filters.

What the greater cost/benefit? Having it be pretty good with realtime capture, or, slightly better with more time investment with a seperate reencode?

[Nelson37]

Suggestions -

Use the original source, you are making a copy of a copy. The best you could do is equal an already-compressed source. GIGO. Use the best quality of input you can get. That means the S-Video output from the cable or satellite box.

As stated, viewing on TV will solve much of your problem. PC monitor being much higher resolution, and with different color settings, makes minor or invisible artifacts much more noticeable.

When you begin burning, use an RW and adjust your brightness and color settings on the ATI. This will vary, but I find bumping up color significantly, brightness slightly less so, and tint down a hair creates a capture file indistinguishable from original broadcast, both played on TV. Many cable channels repeat shows several times a day, useful for this test.

I agree with raising motion setting to 99. I use VBR with target set within 500 of MAX. Larger difference seems to cause pixelation.
I also reboot before every capture. Otherwise results can be erratic.

If you have a very clean signal, like dish or digital cable, use no VideoSoap. Noisy analog signals, light or medium Soft seems to work best.

Use Record Cropped with Mpeg type set to DVD. It crops the overscan area and adds black bars for proper resolution. You also may want to experiment with the IVTC.

Does an AVI look better than a real-time MPEG? Most likely. But encode that AVI, and compare it to a well-done real-time MPEG, that was edited and burnt many hours previously, and the difference gets much harder to see.

Almost forgot. Do not use I-frame only unless you intend to re-encode. Very wasteful of bitrate and unless this is extremely high can cause defects. Also is non-standard.

[lordsmurf]

Capture was done on modified DVD High setting MPEG2 720x480, I frames only, 8 MB/sec max & target, 70 motion, 256k 48kHz 16 bit audio, no VIDEOSOAP. The video source is an UltimateTV PVR (Microsoft's Tivo product) capture of DirecTV run thru S-video into the AIW.

I missed this initially. You've set yourself up for an inferior capture.
The 70% did it most. Not optimal.

I frames is for editing only, and even then, this is just an imperfect form of MJPEG. Use a delta 1-4-2 or similar 1-2-2/1-3-2 pattern of IPB. TIVO recaptures to my knowledge. So you'll be making the 3rd digital generation of MPEG, something that will be lossy with each generation. Satellite is not perfect at all anyway. Some of the errors are just translating to the new file.

Audio looks good, VideoSoap only as needed. The 720x480 may be overkill, so try 352x480 at 99% motion setting with VBR 3.8 avg and 4.6 max VBR. That'll get a least 2 hours or more on a DVD. Also do interlaced MPEG-2 as per my guides, maybe do the MPEG2-DVD with cropping method to cut overscan image/noise.

Most of this is on my site.

And of course, view on tv.

The video color, etc needs to be set and tested based on YOUR tv, DVD player, etc. Note: I have to turn DOWN the color on my VHS captures, otherwise it picks up chroma noise.