I believe I've rounded my purchase choices down to either the Matrox G400 or the ATI AIW 128. Could people with first hand experience comment on the pros and cons of these products. I'm very picky about video quality. ANY blockiness and I'm pissed. Do the boards have bitrate control? Currently I have the ATI TV WONDER and I see no evidence of bitrate control.

-- may (mlea@uswest.net), March 08, 2000

Answers

I have the Broadway 4.0 and I am convinced that eliminating blockiness is impossible unless you use a higher bit rate. Anything in motion has blockiness around it at the standard video cd bit rate. I think it's a matter of simple mathematics. You are limited to something like 1.15 million bits per second.

-- Al McCraw (amccraw@ix.netcom.com), March 08, 2000.

I have a G400, with a Rainbow Runner addon. It has limited bitrate control selections, but remember it does not capture to Mpeg. You are given a few preset resolutions and a few compression levels to select from at each resolution. Since this is an MJpeg card, you'll want to capture at the highest resolution with the lowest compression that your drive space will allow.

The video quality is excellent in native Mjpeg, esp if you capture and full frame NTSC. The resulting Mpeg quality varies widely depending on the source footage and the encoder/encoding options used. I have acheived excellent results with this board. YMMV.

If you are hoping to capture directly to Mpeg1 or Mpeg2, this card is not for you. But if you want quality, and are willing to let a good software encoder do it's job, this might be the board for you. I can't comment on the ATI, since I have no direct experience with the newer AIW boards.

-- Sean (sean@magnuminvestments.com), March 08, 2000.

The AIW 128 32Mb & 16Mb 2xAGP or PCI has bitrate control that falls from 400kb/s to 8000kb/s for both mpeg1, mpeg2. AVI has about four codecs and two of which are ATI proprietary codecs. The bitrate controllers is in the format of a slider. Furthermore, there is a motion estimation slider that work with your CPU to control the blockiness (sorta like a low pass filter or half pixel vs full pixel in panasonic). The higher the numerical value you slide the controller the less blockiness you'll get even at the VCD bitrate(the blockiness will be there if you squint hard enough during high motion scene at VCD bitrate); However, it will drop frames during capture if your CPU is weak. The slider's range is between 1 to 20; I am using about 17 which is the best i can get without frame drop(CPU range = 500MHz and above, tested). If you are capturing in mpeg2 format then you can use the full 20 without any problem. 10 and below = blockiness. Capturing AVI from this board can be an issue if you're using anything other then ATI codecs. VCR1 creates huge AVI file size but the quality is very good without any blockiness. VCR2 create smaller file size with similar quality but the blockiness is very apparent. Needless to say AVI is not for me with this board. If i have a software that will automatically slice the AVI into 2Gigs chunks while capturing, maybe. Then again a 20Gigs hard drive will be taken up within 2 hours from this board. I usually capture using mpeg format: mpeg1 @ 3200kb/s @ 352x288 with slider set to 17 (for making vcd) or mpeg2 720x480 6100kb/s with slider @ 20 (for making svcd). Process the mpeg1 through panasonic to vcd format and burn or process the mpeg2 through DVMpeg, ReMPEG2, and I-author and burn.

-- lnguyen (wingstarzz@hotmail.com), March 08, 2000.

I used to own the ATI AIW 128 32Mb for 2 months. I reason why I gave it up is because the quality is below my expectation. After many hours of adjusting the setting of achieving best video quality, I think the quality is quite the same as my previous Snazzi PCI capture card. However, the Snazzi is much more user friendly and easier to burn VCD. The best if you can see a demo of this card before you decide to buy. Good luck.

-- Bach (weiseme@hotmail.com), March 09, 2000.

The AIW's fame revolves around four codecs that get installed with it (two proprietary), plus MPEG-1 and MPEG-2 direct capture. The G400 Marvel (which belongs to the same category as the AIW, ie., all-in- one AGP cards, not to be confused with the Millenium G400 which will require a Rainbow Runner add-on for vidcap purposes) revolves mainly around its proprietary MJPEG codec. The G400 doesn't capture to MPEG- 2, but a bundled app lets you convert your MJPEG-coded AVIs later to that format. I have tried both, and personally, MJPEG is a bit better than ATI VCR1 in that captures of the same resolution, etc from the same source yielded a smaller size file with the MJPEG compared with the VCR1 codec. One other thing that will make me choose G400 is that it allows capture from PAL, NTSC, and SECAM sources with just one model of card; there separate models of AIW for NTSC and PAL/SECAM. SO if you get an AIW to capture NTSC that's all you will be able to capture; too bad if a PAL VHS tape comes bouncing along.

-- EMartinez (epmartinez@yahoo.com), March 09, 2000.