Chopped audio with AVI_IO

[egov]

Ok, here's some update on the audio problem:
I restored the original BIOS settings, reseted the G200 BIOS, disabled the onboard audio and plugged back the AWE64 ISA. Erased and installed Windows. The audio seems to be better during recording, but it still pops and the higher the video rate is the worst it is getting. What puzzles me is that when recording MJPEG, even at max quality and size the audio is crystal clear. So, it is not hardware problem after all?

[LvR]

egov

Been following your posts here and on Matrox

You are partly to blame for the confusion - "with Mjpeg sound is crystal clear" and "sound is not distorted,but chopped up"???

This is quite clearly a hardware issue where the PCI bus is unable to handle the amount of data fed through it while capturing non-Matrox Mjpeg avis.

With Matrox hardware captures, your PCI datarate is the lowest because all the work is done by the G200 card itself leaving a lot/bit more bandwith for audio data throughput. While doing raw RGB captures and the compressing with a software codec, you use just about all the bandwidth available, with the result that your audio starts to suffer and cant keep up.

------------------
Lawrence

[egov]

I don't feel that datarate is the problem because:

1. I had not such a problem with All in Wonder AGP on the same configuration, capturing 640x480 with software compression.
2. The problem exist, even if I capture at 11Khz mono audio settings.
3. The problem exist even when I try the onboard audio.

[egov]

OK, here's more update on the audio problem. Hope it will give you some clue to help me. First, here's my hardware configuration before installing the drivers:
http://server3002.freeyellow.com/statii/hardware.txt

So, as I said, when I capture MJPEG using VirtualDub at 44/16Khz and 702x480 the audio is clear even though the data rate is near the maximum capacity of the drive (CPU usage is ~30%). When capturing using the YUY2 and software codec at 320x240, even when the datarate is 3 times lower and the CPU usage is near 5%, the audio is chopped. The larger is the picture the more chopped it becomes. I also noticed that sometimes, after finishing the capture with HuffYuv or PICVideo MJPEG the computer would freeze for about a minute. But if I capture with no audio it never does it. I tried playing with the audio card settings, unplugged the AWE64 sound blaster and played with the onboard audio -- the results remains the same. I feel it is either DMA or IRQ conflict, but have no idea how to resolve it and Matrox would not give me a hand, because they don't support anything else but their hardware MJPEG, which turned out to be a great disappointment to me (see http://forums.murc.ws/ubb/Forum2/HTML/003709.html )

[egov]

Today I pulled out all cards except the Matrox and ths SB64AWE ISA. Pulled out and plugged back all IDE cables and memories. Resetted the computer BIOS, enabled the USB. Deleted the boot partition on drive C:, booted from the original WIN98se CD and installed clean Windows. Installed the latest VIA, VideoToold 1.52 and Videodrivers w9x_555 from the hard drive. Downloaded the Windows Update.

The computer started crashing after the first capture. The audio remains chopped.

[egov]

I suspect more and more IRQ conflict. How can I check it in Windows 98?

[KRSESQ]

Egov:

Did you check control panel? Double-click "System" icon, select "Device Manager" tab, and double-click the "Computer" icon at the top of the list. A window will open that will give you the option to view all IRQ settings and the associated devices. Some devices share IRQs normally. For instance, you may see many entrys for "IRQ holder for PCI steering." Also, your Bus Master controllers will probably be sharing IRQs with the IDE Controllers.

This listing should indicate IRQ conflicts. I assume you've done all this already. I just bring it up because of my old tech support training. If this doesn't tell you anything, go to

www.Sisoftware.co.uk/sandra

and download the free Standard Version of their diagnostic software. It should tell you everything you could want to know about your system (and if it doesn't, there's always the pay version ).

Hope this helps.

Kevin

[This message has been edited by KRSESQ (edited 29 January 2001).]

[Dr Mordrid]

Do I read that spec sheet right? You are using a VIA chipped mainboard and have a PCI modem and NIC in it?

Before you go any further try this:

Create a custom user profile with the NIC, PCI modem and any other non-editing hardware disabled in the Device Manager.

My experience with VIA boards and high data rate captures is that unless they are set up this way problems are just about guaranteed due to high bus loading. Even then....

Dr. Mordrid

[Sciascia]

Not to insult you, but what are your audio levels at in PC VCR? It really sounds like you might be getting some digital clipping if you are having problems with 11kHz mono and lower video data rates. There are some sliders for audio that PC VCR has that effect the audio in all of your capture applications. I have had some really bad experience with operators when we went to digital audio editors, they would try to set their reference levels at +4dB=0VU (using 1kHz tone) and it would just try to compress "live" audio. Unfortunately digital does not have the dynamic headroom of linear tape (about 22dB), so instead of a nice "warm" linear compression and gradual rolloff-- CHOP, CLIP, POP!! I did some research and the actual reference is -18dB=0VU. Guess what, it sounds great and they all use it now.

Instead of trying to setup for -18dB, just try lowering your audio. With some gear, it might be +10dB (usually higher quality gear). (I would start between 1/4 to half level for all inputs)

Just thought that it might be worth a shot.

[This message has been edited by Sciascia (edited 29 January 2001).]

[egov]

OK, I checked the control panel. The only possible conflicts I see are:

11: ACPI ICQ HOLDER FOR PCI IRQ STEERING
11: MATROX MARVEL G200 AGP

I pulled out all PCI devices (network card & PCI modem) but the problem with the audio persists. However, if I capture in MJPEG, the sound is fine, even if the overall data rate is higher than the one with YUY2, when the audio gets chopped. But Dr. Mordrid is right about the bus loading, because the higher the frame size/audio KHz the more frantically is the audio distorted. If I capture at 320x240 YUY/HuufYuv/22KHz the audio is just popping. But if I increase the frame size to 704x480 the audio sounds like on the sample provided above. The only thing I don't understand is why it does it even when all PCI cards are out???

[Technoid]

Lets start from the beginnig and upp

Bios:

Standard (hdd,fdd etc)

Make sure every unused Ide point (primary master , slave, secondary master, slave) that is not used is maked as "none" (this has nothing to do with Ide channels!!)

Advanced

Turn off any antiviral protectors!

Disable HDD S.M.A.R.T.

Internal & external cache should always be enabled.

CPU L2 cache ECC Checking should also be enabled (Intel CPU's).

Processor number feature = off by al means

Boot up floppy seek = disabled

Gate A20 option = Fast


ADVANCED Chipset features:

Memory Interleaving = If present Enable

(Note about AGP driving on VIA boards; they are best left in standard values)

VGA boot from AGP/PCI
Init Display first agp/pci (depends on vid bord ).

Agp aperture size: 128 or higher (if G400 based board otherwise x2 the amount wanted for agp memmory)

CPU Latency Timer = *disabled* very important

Cpu to Pci Write buffer = enabled

Pci dynamic bursting = enabled

Pci Delay Transaction = *disabled* very important

8/16 bit recovery time = higher values give ISA cards more time to do their job

INTEGRATED STUFF:

AC97 AUDIO/MODEM: if in use AUTO if not DISABLED

PNP/PCI SETUP:

PNP OS installed = Yes

Asign IRQ For VGA = Enabled
--------------------------------

Windows (And by that I Mean W9x)

Intel Chipsets:
Run intel inf update (only really needed if on w95 org or with 8xx chipsets)

ATA wonderdrivers if ATA 100 Hdd (they kill my CDRW in W2K so i Love them but this is about W9x and there they work )

VIA Chipsets:
Install VIA4in1,
Install VGA drivers (they all assume you have a Intel chipset board and thrash the AGP drivers for VIA)
Install Via4in1 (se above why!)

Run SFC and Extract
Configmg.vxd
Vdd.vxd
Vflatd.vxd
Vdmad.vxd
Vcomm.vxd
Ntkern.vxd
To your Windows\system\ directory and reboot

I have tons of other Capture tweaking in W9x tips but you have definitely read or heard them before by The great Persons roaming the Forum like Dr. Mordrid!
___________________________________

With all these steps taken it should not differ if you have an SB16 ISA or an SBLive PCI!!
(i have an very old SBLive, the newer ones might be the FR killers Doc accuses them for!)

I don?t advice any one to use onboard sound because they are CPU and BUS hogs that makes an SBlive pale in comparison!

When I first got my RRG I had sound problems that seemed to be from VIA+SBLive BUT when they didn?t disappear when I changed to an ISA SB64 AWE I changed Mainboard and they did disappear!!

In retrospect I should have been more patient and tried more tweaking and actualy used the Via drivers (this was before VIA4in1 was conceived by VIA ) which I by some reason
(I don't remember) didn?t trust!

But instead I just blamed via and got me an expensive BX board and a horrendously overpriced Intel P3, 450MHz!

If I had hade the knowledge that I have today I would have tamed the Via Chipset and gone directly to A Duron setup when I ran out of CPU power (skipping the pricy P3)!

[KRSESQ]

Egov:

The G200 sharing IRQ with PCI steering is normal. It shouldn't cause a problem BUT check the following thread for more info on ACPI:

http://forums.murc.ws/ubb/Forum2/HTML/004938.html

It may be worthwhile to follow Pertti's advice and reinstall windows using the parameters he gives for disabling ACPI. (remember to disable ACPI in BIOS beforehand.)

Kevin

[egov]

Guys, I am giving it up. I wiped out Windows completely, installed windows with the recommended option. As soon as I installed the videotools V1.54 the machine crashed on blue screen. Either my Matrox is deffective, either the motherboard is crap or the Matrox drivers are not good.

[Technoid]

The YUY2 support is broken in vt 1.54!

[Dr Mordrid]

Yup. You have to use 1.52 to use YUY2.

Dr. Mordrid


[This message has been edited by Dr Mordrid (edited 31 January 2001).]