ATI AIW 128 720x480 mpeg captures have horizontal tearing

[cybertheque]

Greetings,

Hardware:

ATI AIW 128 AGP, CPU PIII-550, ultradma IDE HD

Video Source:

Live sources feeding DPS TBC-II which drives ATI video in.
S-Video and composite NTSC

Software:

Win2k Pro SP4, DirectX 8.1, ATI Rage 128/AIW 513013279

My attempts to capture at 720x480, constant or variable bitrate, I-frames only or
various interframe compression settings, mpeg-1 or 2, etc. all have produced
files which play back with what resembles horizontal tearing (loss of synch).
Playing the files on various machines of different speeds, with different
hardware and software mpeg decoders, in various applications including
vdubmod, vlc, wmp9, ATI file player, produce the same result. No frames
were dropped during capture.

Example still image and short mpeg clip:

http://www.cybertheque.org/tmp/aiw-probs

Note that capture at 640x480 works.

I have not seen Macrovision distortion; does it look like this? Since the tests
are done from my in-house live sources through a TBC, Macrovision shouldn't
be an issue.

Thanks,

Michael

[minidv2dvd]

have you checked task manager while capturing? your system may not have the horsepower to capture, encode and write the file - to that high a spec. see if it's spiking or pegged at 100% cpu usage during a capture.

try lowering the bitrate to 3000kbps cbr normal dvd spec mpeg-2 and see if it helps.

[lordsmurf]

This is not likely anything to do with the computer, but with the VCR and/or TBC.

[cybertheque]

have you checked task manager while capturing? your system may not have the horsepower to capture, encode and write the file - to that high a spec. see if it's spiking or pegged at 100% cpu usage during a capture.

try lowering the bitrate to 3000kbps cbr normal dvd spec mpeg-2 and see if it helps.

CPU usage didn't exceed forty percent during that capture. I tried mpeg-2 at cbr from 1000 to 8000 kbps,
both I-frame only and with interframe compression but the sync tearing persists. I can record 640x480
at 10000kbps I-frame only cbr or vbr, interlaced or progressive with no problems.

Michael

[FulciLives]

Just a thought here but have you tried 704x480 resolution? This is still DVD compliant!

It occurred to me that since 640x480 works but not 720x480 then perhaps another resolution like 704x480 may work and if it does then that is ... as I said ... DVD compliant. So if 704x480 works then problem solved.

However the fact that 720x480 does not work yet 640x480 does work ... well that sounds like a "clue" to me. I mean it makes NO sense that one works but not the other yet it is true so ... there must be a reason. Of course that is the answer you seek ... an answer I don't know!

So as a work around try 704x480 and if it works then just use that and move forward.

- John "FulciLives" Coleman

[cybertheque]

"lordsmurf" wrote:
> This is not likely anything to do with the computer, but with the VCR and/or TBC.

FWIW, Off-the-air recording with the tuner does the same thing -- no external TBC
or source involved there ;)

Michael;

[cybertheque]

FulciLives" wrote:

> Just a thought here but have you tried 704x480 resolution? This is still DVD compliant!

I'd like to try it but the driver won't let me; if you can suggest a way to do it (driver replacement,
tweak, etc.) I would be grateful ;) AVI cap (in vdubmod for example) doesn't do anything greater
than 240 vertical with this board, although I have read of methods to make the "Theater"-based
boards go higher. MMC 7.2 vidcap offers nothing between 640x480 and 720x480, and is the
latest MMC for this board (7.7 requires the Theater-based boards).

Other posters have recommended in the past to capture I-frame only at the highest bitrate
sustainable on the PC when using this board to permit editing without a transcoding step.

Michael

[FulciLives]

MPEG-2 capture using "I" frame only encoding (along with a very high CBR video bitrate) will give you a file that is "best" for editing (at least when it comes to MPEG video) if you intend to do "extensive" editing . I'm talking like real "home video" type editing where you need to cut a lot of stuff out or add stuff from mutliple capture files or maybe re-arrange stuff and add transitions and titles etc.

However if this is stuff that doesn't need much editing ... maybe just the front and end ... even a TV show where you cut out the commercial breaks ... then you don't need "I" frame only encoding. For this type of editing you can use a variety of tools like MPEG-VCR or VideoRedo or even TMPGEnc DVD Author etc.

- John "FulciLives" Coleman

[cybertheque]

"FulciLives" wrote:
<snip>
> However if this is stuff that doesn't need much editing ... maybe just the front and end
> ... even a TV show where you cut out the commercial breaks ... then you don't need
> "I" frame only encoding. For this type of editing you can use a variety of tools like ...
<snip>

For sure; for simple cuts I write an EDL with timecodes and use command-line tools
to process the source file. My intent is to capture at best resolution available with the
hardware and edit in Premiere.

In another forum, someone mentioned similar horizontal sync scrambling with mpeg
captures, while running a frame server, but never got a solution. I would appreciate a
verification that ATI's driver isn't broken for this board; a report from someone who
has captured 720x480 mpeg with the AIW128 Bt829-based board. Or for that matter,
a report of any Bt829-based product doing it.

Michael

[cybertheque]

"cybertheque" wrote:
> I would appreciate a verification that ATI's driver isn't broken for this board;
> a report from someone who has captured 720x480 mpeg with the AIW128
> Bt829-based board. Or for that matter, a report of any Bt829-based product
> doing it.

Well, it turns out that my board isn't an AIW128 but instead it is an AIWPro
(8MB); the capture hardware is the same however. ATI official specs for
both versions state max 640x480 30fps capture (AVI uncompressed when
running under Win9x, mpeg only available for AIW128 under Win9x at
the time of writing). Win2k drivers must have added mpeg support for the
AIWPro after release of those specs. In any case, MMC 7.2 capture utility
must not distinguish which board is installed in order to disable unsupported
formats, so evidently 720x480 only works on AIW128 32MB Theater and
AIW Radeon boards (confirmation please?).

Here is the URL for the specs (couldn't find it in the US site but the UK site
has it -- the text-only cached version is easier to read):

http://209.85.173.104/search?q=cache:5HYzdQhDYK0J:ati.amd.com/uk/products/faqs/aiwfaq....&gl=us&strip=1

(hope that long URL survives text entry).

Michael

[Nelson37]

Had two different AIW 128 boards, both 8mb and 16mb, running under Win2k. Captured at DVD-res MPG2, with a similar CPU - AMD 450-500, K2 and K3. Never, at any time, experienced anything like what you are seeing, other than with a damaged VHS tape.

Did some VHS and DVD capture testing, mostly live video, at that time analog and then digital cable source.

Several different drivers and MMC versions, IIRC got up to 7.7 or 7.8 with this board, hit a wall at 8.x, I believe. There was a reported but unsubstantiated rumour of a method to get 8.x running, tried a few other tricks but no success.

I would remove the TBC as it should not be needed with sources other than VHS. Use S-video port, though test others as well as the Coax input. Eliminate sources of frequency interference, basically move anything electrical 5-15 feet away from unit, also cables. Test removing soundcard, eliminate overclock if present. Clean power needed, recommend an APC unit.

The MPG video did not reach IMO excellent quality until I moved up the CPU speed, AMD - 1000, 1200, 1400, finally an 1800 where it stayed for a long time.

The card can do it, no question, I would be dead certain it is either an interference and/or source problem, or the board is defective.

[minidv2dvd]

here are the original specs. you are right - those cards can only capture up to 640x480.

http://ati.amd.com/uk/products/faqs/aiwfaq.html

[free is better]

try to get your hands on the aiw 128 pro 32 mb and mmc 7.9. reliable combination that can capture at dvd compliant resolutions.

[lordsmurf]

Get a Theatre-based chipset, not the crappy BT-based boards. The CPU is vastly under-powered, however.

[Nelson37]

I misstated, my two boards were 16 and 32mb. Both were capable of creating a 720x480 file. I still have the disks made from these. Still have the cards, too.

There is a difference between CAPTURE RESOLUTION and RESOLUTION OF CREATED FILE. Basically, there is a slight resize happening.

Have you done any editing of Registry settings? Thinking back, I do seem to recall getting some similar effects when testing various manual settings.

[jagabo]

Yes, you have some kind of problem where the software and hardware are not agreeing on the frame size. I was able to reconstruct a little of the image from your post by assuming a 728 pixel wide image:



It still has errors but you can see that the actual image data is not what was expected by the software.

[cybertheque]

"jagabo" wrote:

> Yes, you have some kind of problem where the software and hardware are not agreeing
> on the frame size. I was able to reconstruct a little of the image from your post by
> assuming a 728 pixel wide image:

> https://forum.videohelp.com/images/guides/p1887824/728.jpg[/img]

> It still has errors but you can see that the actual image data is not what was expected
> by the software.

What did you do to process the data (programs or techniques)?

For now, I have abandoned my work with AIW Pro and 128 cards; I discovered that an
early version of the AIW 128 came with the VIP header populated and functional, but my
tests with other AIW 128 cards I had on hand, in Win2k hosts, produced nothing but
headaches -- crashes or hangs depending on selected capture resolution and compression.
I tried various driver and MMC versions, and each combination had different failures
and none was reliable or even useful. Only the 128 Pro with MS distribution drivers and
MMC 7.2 essentially worked at all for me.

Instead, I installed a newly found Rage 128 Xpert 2000 8MB card with the VIP header,
made the funky AMC <-> VIP 26 pin ribbon cable (I will provide the wirelist and construction
details on request) and am pleased with its performance handling my overlay devices.

For vidcap, I will have to juggle PCI slots to add a new board, probably a hardware MJPEG
device.

Michael