AVI-IO - miscellaneous information

This page provides miscellaneous information of AVI-IO.

Known limitations

The following limitations are known to exist in AVI-IO.

With some capture hardware it's always necessary that the "Video Format" is set before you try to capture the first time. Otherwise you get an message box "Error initializing capture!" This is however not a limitation of AVI-IO. It's a driver issue.

AVI-IO currently only supports PCM audio formats.

Future plans

We are considering the following extensions of AVI-IO:

You may have noticed that the player part of AVI-IO does not have player controls. We will add such controls which will allow you to move back and forth along the footage defined in the play list as if it would be one single file.

We are further improving support for DV cards (IEEE1394 boards). This includes device controls, print back to tape and support for some boards using propriatary board interfaces.


Note, AVI-IO does some internal buffering of frames to allow to do it's job perfectly. The I/O Buffer's on the status line show how many buffers are currently allocated and what the maximum is. It's shown to help you set the optimal data rate your capture hardware can handle. The number must stay below the maximum, or the capture process will be terminated. Generally spoken you should adjust your data rate so as the number of allocated buffers usually does not go above 20. Like this you have a "security" buffer zone to allow for short "hicks" your HD system might have. Like this frame drops are avoided that other capture software would experience in the same situation. Again, this does not really allow you to set a higher data rate, but it makes AVI-IO run smoothly avoiding dropped frames where ever possible. It's normal that even at lower settings you see the number of I/O Buff's bounce.

The tool (on all platforms) will create individual AVI's of up to 4GB (2GB on FAT16 formatted drives) size each. Please note however that most Windows video software (players, NLE and the like) do not really work with files bigger than 2GB. Note that the player part of AVI-IO will play such files without problems.

Be aware that there are players NOT capable of playing files bigger than 1GB. This applies for instance if you try to play an avi over the "Properties" -> "Test" tab in explorer.

Note, if needed AVI-IO insert's frames to keep synchronization between audio and video, while all other capture tools known to us don't. Such capture tools (as a consequence) may not report any drop's BUT audio and video shifts in such cases if you capture over long periods. We feel that inserting frames (and reporting them as drops) is better than letting audio and video shift, because such shifts are soon noticeable especially if you capture talking people. The reason for such shift's (if they happen at all) is caused by the sound card and/or video capture card used. If one (or both) of these devices do not keep exactly the frequency requested by you (i.e. 29.97 fps 44100Hz or whatever) audio and video will shift if you capture using a different capture tool. AVI-IO corrects this behavior only if needed giving perfect lip synchronized captures over hours using even unstable (cheap) hardware!!! - The drawback are some reported drops which however should not be noticed during playback.

If you experience crashes or get the error message "Not enough RAM", make sure virtual memory is turned on. Also make sure that there is enough free HD space available on the drive where the swap file is located (usually drive 'C').

Pinnacle DC10+

In case you use a Pinnacle DC10+, make sure to set the video output and preview option in the DC10+ control panel. You can open the control panel by double clicking on the Pinnacle logo in the taskbar. Without this option AVI-IO cannot successfully play back video with this board.

Iomega buz

In case you use a buz together with the morgan MJPEG software codec, make sure to set drivers section in your system.ini file as follows:


Change it back if you need the Morgan codec. We are considering a checkbox in the player settings which allows to overcome this inconvenience.

DV (Digital Video) boards

Currently AVI-IO supports OHCI compliant boards or any other DV board as long as there is a Video for Windows capture driver installed for it, or a working WDM DirectShow wrapper. The support is currently limited to capturing only and also does not include device controlls. Boards known to work well are the ADS Pyro, the Exsys, SIIG and Pinnacles Studio DV. You need Windows 98SE or Windows 2000 or better, since only those platforms have a working WDM wrapper. Note the following information is important to make AVI-IO work wiht DV devices.


We can't guarantee that AVI-IO works with ALL hardware combinations and situations that are out there in the market. That's one of the reasons why there is a trial version of AVI-IO. However, if it does not work the way you are expecting, try the following things:

1) Capture using VidCap from Microsoft. In case you can't capture using VidCap, you can be almost 100% sure that the problem is NOT related to AVI-IO.

2) Make sure to use a "good" source for your capture. Try another tape. Also make sure to capture using the frame rate of your source signal (29.97 fps for NTSC and 25fps for PAL).

3) Read carefully the
Gotchas section and check if one of the "gotchas" there apply to your situation.

If after following the above things you still think that AVI-IO is doing something wrong, you can send us an e-mail to describing the problem


- The version of AVI-IO you are using -> Help -> about AVI-IO
- The OS type and version
- The hard disc subsystem (ide, scsi, raid and so on)
- The capture hardware used
- As much observations and information as you think we need to understand the problem.


All registered users of AVI-IO will get ALL future major releases of AVI-IO for free and sent to them by e-mail shortly after release date. A major upgrade is when the version number before the "dot" is increased. Minor upgrades only contain bug fixes which don't affect most users or small functional enhancements which are not very important. In case we find and fix a bigger problem, we declare the fixed version as a major upgrade. If you feel that you need a minor upgrade you can get it for free too, but to get it you have to send us an e-mail to telling us that you need a minor update.


Don't forget that there are no warranties associated with this software. While we believe that the software is reasonably bug free and well behaved, we are in no way responsible if the software does not work the way you would expect it to work. If it locks up your computer, garbles your floppy disks or hard drive or does any other harmful thing to your computer - it is entirely your problem. Markus Zingg is not liable for any infringements or damages of third parties' rights resulting in your use of this product. Markus Zingg is in not liable for, and does not warrant the trustworthiness, quality, industrial use, or serviceability of this product for the supposed purpose or any other purposes.

This information may be subject to change. All brand and product names are trademarks and/or registered trademarks of their respective owners. All rights reserved.

(c) 1999 Markus Zingg, Hofmattrain 15, 6033 Buchrain, Switzerland

Back to index