Transcoding CamStudio AVIs using MediaCoder

[JFJohnny5]

Hey all. I'm currently trying to make some video tutorials in response to the request for tutorials on some of my techniques for the Bandit Camp battlemat. Someone here (can't remember the post) had suggested using CamStudio for the screen capture and then transcoding using MediaCoder. But I'm having issues... So for those of you that are familiar with the software, here goes:

I'm having problems transcoding the AVI files that CamStudio creates. There is a color shift.

It does not seem to matter which codec or container I output to. So far I have tried transcoding other AVI files as well as some WMVs which all work fine. I have also tried 3 different versions of MediaCoder on 2 different PCs; one with XP, the other with Vista. So I've ruled out hardware and the MediaCoder software itself. It seems to specifically be the AVIs that CamStudio creates.

I have narrowed it down to the compressor used when creating the AVI. I have three choices - Microsoft Video 1, Cinepak Codec by Radius, and Intel |YUV. And of course, the issue occurs when using the best-looking of the three, Microsoft Video 1. But I have no idea what it might be doing differently. I should also mention that the AVI created by CamStudio plays fine in Media Player with no color shift at all. So the file looks fine at first; it only takes on a color shift when transcoded.

And finally, the color shift is specifically between the Blue and Red channels. The Green channel stays the same, but Blue and Red "switch".

So, any theories or past experience with this issue?

[RobA]

I've usually transcoded from CamStudio using Virtualdub and never experienced what you describe.

Sorry that's not more help

-Rob A>

[JFJohnny5]

I've usually transcoded from CamStudio using Virtualdub and never experienced what you describe.

What do you transcode to? I'm trying to get to MPEG-4 using H.264 or XVid. Virtualdub only seems to support AVI using a handful of compression codecs.

[Redrobes]

I think that would be me recommending CamStudio and MediaCoder but I have not seen any issue like that. I would use the MS codec which is uncompressed and then transcode to XviD which is pretty well supported and very small.

The first thing I would do is download VLC because it uses the same code as media coder as a playback so you usually find that it plays all MediaCoder stuff. Of course thats not a complete solution as you need to get it looking right for anyone but it might narrow it down.

If its on several computers then it would either be a version of the software or a config issue. The trouble is that with video stuff theres more options than you can possibly imagine possible.

Here is a test AVI that I just did with CamStudio and an xvid of it and see if it gives similar results. If not then send me a short CamStudio avi in MS Video 1 and ill see if after transcoding that I get same results.

I will admit that I never ever run MediaPlayer.

[JFJohnny5]

This is so bizarre. I grabbed VLC to test your process. And the basic AVI straight out of CamStudio won't play. Well the play bar moves, but it's just a black screen. This is the same for my CamStudio files as well as the one you posted.

Then I took the file you posted (Lena.avi) and ran it through MediaCoder and got the same color shift.

I'll post my transcoded file so you can see what I mean.

I don't know why my VLC will not play CamStudio AVIs but Media Player will. I also don't know why MediaCoder is creating a color shift. Can you post the settings you're using in MediaCoder? "File > Save as Preset" It will create an XML file you can post. Then I can be sure I am using 100% the settings you are using in MediaCoder.

[Redrobes]

Firstly your movie plays with inverted colors so its in the file as we thought. I am attaching my preset also but I have the feeling it wont help. If my files do not play in VLC then I am starting to think Video Card.

Just humour me and right click on desktop to get video card prefs and then go advanced and there should be a tab for trouble shooting. Set the hardware acceleration to off and ok it. Close all versions of VLC, media player etc and then open VLC and try to play again. If thats ok now then try media coder and if thats ok it will be a video card driver issue. We can go into more detail if that is the case. After, set it back to full accel again tho.

[JFJohnny5]

Yeah, the inverted colors only happen after transcoding. The original AVI, which I can play in Media Player is not inverted.

And I thought video card, driver, etc at first as well. But I have tried this on two different machines with vastly different specs; regarding video cards specifically, one was onboard and the other a 7900 GTX, but also different sound cards, processors, etc. I've pretty much ruled out hardware at this point. And the fact that other AVIs I tried from random sources work fine, but the ones from CamStudio give me problems, really blows my mind.

I've actually been working on this at work all day as I've been asked to do some screen capture training videos. So I won't be able to try the prests until tomorrow. But I'll let you know.

Thanks for all your help though! I really appreciate your willingness to help me work through this.

[RobA]

What do you transcode to? I'm trying to get to MPEG-4 using H.264 or XVid. Virtualdub only seems to support AVI using a handful of compression codecs.

I've got > 23 codecs listed (everything installed?), including XviD and x264

-Rob A>

[JFJohnny5]

I've ended up using a lossless codec written especially for CamStudio that someone at the MediaCoder forums turned me onto. Works great, looks great, and lets me encode with MediaCoder. Still have no idea why I get a color swap with Microsoft Video 1, but oh well. Here's a link to the codec for anyone that wants to try it:

http://www.camstudio.org/CamStudioCodec10.zip

[Redrobes]

Glad you got that sorted out. I don't have any idea what was wrong.