WinTV PVR-250 vs AIW 128 capture

[Bizuser]

I just bought a PVR-250 based on discussions in this forum, to replace my AIW 128.

I did side-by-side comparisons of a VHS tape capture. The AIW wins out but not for obvious reasons ...

With the AIW, I first captured at 480x480, using MJPEG at setting 18 to an avi file. Then ran through TMPG (using avisynth with a smart-deinterlace filter) to create an SVCD-compliant stream (took SEVERAL hours!).

With PVR-250, I captured the same tape direct to MPEG2 using it's SVCD template, then remuxed in the nano... editor to get a compliant stream - quite fast.

The results were virtually identical (thus, PVR-250 comes out ahead on time!).

But then I took my 'raw' avi capture from the ATI card (480x480) and Encoded it to VCD format (352x240) in TMPG (using avisynth, with a bicubic resize, as well as a deinterlace). The result was BETTER! This is not what I expected - how could resizing the original source DOWN to a smaller size, essentially from SVCD size to VCD size, improve things? My guess is that the act of resizing the image cleaned up the blockiness of the image. So what is 'better', one must ask ... The two SVCD versions both exhibited slight edge effects - faint 'shadow' after a distinct line in an image, and also (more noticeable) 'blockiness' in (eg) smooth surfaces such as skin. This latter effect was completely 'cleaned up' in the VCD version, without noticable loss of quality. Since it's counter-intuitive that VCD size should be better than SVCD size, the only thing I can attribute it to is that the resizing is smoothing the image, removing harsher elements of the MPEG encoding?

While it makes sense that the resize is simply cleaning up a problem introduced by use of MJPEG in the AVI capture from the ATI card, it does not explain the situation with the PVR-250, since it's going straight to MPEG2 (I know MJPEG and MPEG are related, but some people say MJPEG is not a good capture format).

I also did a direct capture with AIW at 352x240 (VCD format), MJPEG 18, and encoded to VCD format in TMPG - terrible quality! So capturing at 480x480 and resizing down to VCD was way better than direct capture at VCD format - also something of a surprise. I did not yet try capturing in PVR-250 in VCD format.

Anyway - bottom line is the PVR-250 does a decent job of direct MPEG2 capture, but it's lack of support for 3rd party AVI capture (eg, use with VDub) takes away flexibility I need. So my search (and bank-account drain!) continues ... . Note, MMC software that comes with AIW 128 does not produce a usable MPEG2 stream (not SVCD compliant). MMC 7.7/8 is reported to fix this. MMC 7.7/8 ships with the newer Radeon AIWs I believe. Maybe that's what I need to buy next...

[jfebus]

Hi Bizuser,

Were you able to burn the PVR-250 mpeg file in a DVD? I will like to convert all my family vhs to dvd and found out a lot of problems with the Vitec DCM and the dvd burning.

Is the PVR-250 completeny based on hardware? Can you use your PC with capturing?

Regards,

[Bizuser]

I don't have a DVD burner; only CD Burner - hence my interest in SVCD! I will be buying one soon, though!

The PVR-250 is definitely a hardware solution - virtually no loading on the CPU. Even the hard drive does not get overly stressed, so you can probably get away with capturing while doing other things. But I'd recommend getting the pvr-pci at this point - $40 more, but supports capture by 3rd party apps to AVI format.

I've also noticed that the actual TV display on the monitor is not that great with the pvr-250. With the AIW, the picture is 'perfect' on the screen. With the pvr-250, the picture appears as if it's being rendered through the MPEG2 encoder; so if you have a lower-quality setting on the mpeg-capture page, the quality of the screen display suffers. Not such a big deal, since it always seems to reset back to DVD quality (which is annoying from a capture perspective, as you always have to reset back to SVCD in my case!). The ATI AIW more directly outputs it's image on the monitor, unaffected by any capture settings.

I'm tempted to give AIW another chance at this point ... I hear it's MPEG2 captures are now compliant with SVCD ...

[furdog]

I was able to capture DVD MPEG2 and burn a DVD - worked well. Also VCD. The capture format stays on the last selection.

It is hardware encoding/saving. The only capture app is the WinTV 2000 viewing app. That displays the image as it captures. And yes, it is decoding in software whatever is being cpatured (MPEG 1/2 at whatever resolution). So quality of view compares to quality of capture setting.

That also is the only real source of resource drain - to decode the MPEG 1/2 stream for watching while capturing. Have seen mention of turning off the display, for more efficient, but have never done. Low resource usage generally, has not generally been a problem.

Is not really a windows Video Capture device, but a specialize hardware encoder whose output is streamed to a file. Windows and all other apps don't really know it is there. (A plus in my case, since my DC-30 Plus does not like two capture devices in the same box).

Strictly MPEG1/2 capture - flexible settings. Good at what it does for reasonable price. Can be work to get it going (get latest drivers), but o.k. once working (scheduler sometimes a little flaky, channel change response slow). Not a good format for a lot of editing, but o.k. basic cut out commercials.

[jfebus]

Hi furdog,

Did you get any artifacts or funny blockinnes when playing the captured file in you DVD player?

Regards,

[jfebus]

Any having this problems with any of the cards?

https://www.videohelp.com/forum/viewtopic.php?t=144370

regards..

[furdog]

jfebus,

Did not notice any artifacts or blockiness. It was an old Black & White christmas movie captured through the tuner. DVD Long Play mode(6.2 MB/Sec, 720x480, 48 Khz) mode.

Also had converted Store bought christmas animated to DVD (Standard Play 8 MB/Sec, 720x480, 48 Khz mode). Grinch & Rugrats. Composite out, to composite in. Also played o.k.

Used Ulead DVD Movie Factory SE that came with it to author CD. Write ISO and Directory, and burn to DVD-R using the VOB Instant DVD that came with drive (& supported 2X burn).

[furdog]

The only time that I have noticed the artifacts shown in the thread referenced was when I got the first USB Instant DVD device, which had a number of problems, and I returned it.