[Danilo Dumjahn]"for a live projection we need a videoplayer which has the ability to queue several videos or chapterize one long video."
For Mac-based video playback with basic editing capability, you might look at Playback Pro -- it's an outstanding application. Pro Video Player is the other big Mac-based playback option.
[Danilo Dumjahn]"btw, i'm on a mac, there is not much budget for solutions like watchout, etc. and we got a 3840x1080 videosignal sent through a matrox triplehead2go.."
Here's where it gets tricky. You've got the budget for a widescreen or multiple independent screens, but not much for proper playback? The TripleHead2Go is a great product, but it takes a beefy computer to push a 3840x1080 video. If your video is heavily compressed, you need fast processors to play it back. If it's lightly compressed, you need a fast disk subsystem. Either way, I hope you will have a pair of well-equipped Mac Pros available for this.
Sync rolls (whether from DDRs or multiple output systems like a Watchout rig) or dual-channel DDRs are a great way to increase reliability for large format playback. We've used dual-channel DDRs built for stereoscopic playback to run widescreen sync rolls from a single unit with great success.
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