Access violation Error quite frequently

[jgourd]

When using the program and with an MPEG file created in BeyondTV it will randomly terminate with an access violation error. It usually happens at the same time as a mouse click or when first opening the file. Subsequent attempts will work but I have to save my project file after every change so I do not lose any work.

"Error: Access violation at 0x004097FE (tried to read from 0xFFFFFFFF), program terminated."

I am opening the files by opening up the BTV XML files as a project.

v1.5.5.221

[DanR]

Sorry you are having this problem. This isn't a common problem so I'll ask you to work with us as we try and solve it.

1) What graphics card are you using?

2) Audio card?

3) Have you tried switching between YUV on and off? (Tools>Options>SoundDisplay)

4) How about switching between WAV / DirectSound?

5) Which OS do you run and how much memory do you have?

5) Does the problem only happen when opening the XML project? Perhaps you could try opening the XML project and immediately saving it as a VideoReDo project. Close the project and restart with the VideoReDo project. I'd like to figure out if its related to the XML processing?

[jgourd]

Sorry you are having this problem. This isn't a common problem so I'll ask you to work with us as we try and solve it.

1) What graphics card are you using?

2) Audio card?

3) Have you tried switching between YUV on and off? (Tools>Options>SoundDisplay)

4) How about switching between WAV / DirectSound?

5) Which OS do you run and how much memory do you have?

5) Does the problem only happen when opening the XML project? Perhaps you could try opening the XML project and immediately saving it as a VideoReDo project. Close the project and restart with the VideoReDo project. I'd like to figure out if its related to the XML processing?

1. ATI Radeon 9800Pro
2. SB Audigy 2 USB2 edition
3. Yes, no difference.
4. Haven't tried switching sound.
5a XP Pro SP1, Dual Xeon P4 with 1Gig RAM
5b. I'll have to do more research. Here is what typically happens:

I open the XML files as a project, I get the error and VideoReDo crashes. I restart and then I can open the project just fine. I go about verifiying the cut points and it will sometimes crash on seeking to a different location in the file. I create a temp. project file and save it frequently. I go to save the new MPEG file, it crashes. I re-open VideoReDo, open my temporary project file and save the MPEG file again and this time it will work.

Last night this behavior was observed quite consistantly. The files were all DVD compliant MPEGs created by BTV using the Adaptec VideOh! MediaCenter with MPEG compression in hardware. If need be I can make a DVD-ROM withe the MPEG and XML file and mail it to you.

I am a former Womble user who has just just discovered you great little program.

[DanR]

Thanks for the info. I noticed you're running dual CPUs. Is it possible to temporarily run on a single CPU or peg VideoReDo to a single CPU? There are multiple threads going on inside VideoReDo, and while we try our best to use proper thread synchronization your dual CPUs might be highlighting a problem.

[jgourd]

Thanks for the info. I noticed you're running dual CPUs. Is it possible to temporarily run on a single CPU or peg VideoReDo to a single CPU? There are multiple threads going on inside VideoReDo, and while we try our best to use proper thread synchronization your dual CPUs might be highlighting a problem.

When I get home I'll try to change the affinity to a single CPU. BTW I also have hyper threading turned on so my OS thinks I have 4 CPUs.

[DanR]

I have hyperthreading on as well (single P4), but I don't think it really functions like a true dual CPU. If you're technical I'd be glad to discuss why. But, nonetheless, I'm envious of your system, it must really fly :)

[jgourd]

I have hyperthreading on as well (single P4), but I don't think it really functions like a true dual CPU. If you're technical I'd be glad to discuss why. But, nonetheless, I'm envious of your system, it must really fly :)

Yeah, it flies good. I just built it two week ago. It was an upgrade from a dual AMD. I also have one of those Silicon Graphics 16x9 LCDs connected via DVI-Digital. I also have a bunch of striped drives in the system but I doubt that has any bearing on the issue at hand.

I am technical, I was a software developer for a while. Now I just do system administration. I hated writing code in a production environment with deadlines and such.

When I get home I'll do the test and we can see if it helps.

[DanR]

Yeah, it flies good. I just built it two week ago. It was an upgrade from a dual AMDI'm considering a duallie as well. If you don't mind, email me at support@VideoReDo.com. I'd like to get your insight into what it would take to put one of these together.

[Anonymous]

Hi Dan,

I am running a trial version of VideoReDo (about to buy, just holding out for MPEG1 support :wink: )

I am on an HP XW8000 (dual Xeon 3.06 and 2GB RAM). Running Win2K Pro SP4 with all recent MS patches. Hyperthreading off as Win2k Pro only supports 2 cpu's.

I get occasional crashing as described. Haven't set process affinity to a single cpu.

BTW what makes you say that hyperthreading isn't like a real dual CPU? Sure you don't get any more execution units to play with, but the state of 2 virtual cpus is maintained in the silicon and even the OS (Win2k) can't tell that it isn't two real cpus.

Cheers,

Graham

[Anonymous]

Forgot to mention (thought I presume you have a log of this from the update mechanism) that I'm running 1.5.5.221

Cheers,

Graham

[jgourd]

I also forgot to mention that pinning the app to a single CPU fixes the problem completely.

I have arranged to send Dan a Dual CPU motherboard to use in his development environment so a fix is in the works. :D

[DanR]

BTW what makes you say that hyperthreading isn't like a real dual CPU? Sure you don't get any more execution units to play with, but the state of 2 virtual cpus is maintained in the silicon and even the OS (Win2k) can't tell that it isn't two real cpus. First off, I don't want to start a war on the benefits of Hyperthreading vs. non-hyperthreading. We can leave that to the many sites that discuss CPU and MOBO architectures. However, the reason I say that hypertheading isn't really the equivalent of dual CPUs is what you say, "the single execution unit." Lets say the pre-fetch pipeline is 10-30 instructions for each of the two hperthread units, the part that is being muti-tasked inside the CPU. But, once an instruction reaches the exectuion unit the other thread has to stall. This means that two tasks, or threads in this case, can't really overlap each other to any great extent. One thread will stall until the other completes its current instruction.

From an application perspective, this implies a similar level of thread synchronization that exists in a single CPU enviornment. Much, much lower chance of one thread stompping on another at the same time.

[jgourd]

The moterboard is on its way.

[DanR]

Thanks very much. I'll set it up as soon as it arrives.