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OpenGL Streaming video and OpenGL

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I am wanting to write an application that would take streaming input from 4 or 6 cameras. In the case of the four cameras, they would be arranged to point in 4 horizontal directions and in the case of 6, it would the same as for the 4, except with additional cameras pointing above and below. The input of the cameras would then be mapped into a 3D space, so that you could look around and as if you were there. Imagine something like streaming Quicktime VR. First, I would be curious to know whether there have been any projects that have attempted to do anything similar? Secondly, what do yo think the best approach would be for mapping multiple real-time video in 3D space? At this point I am still trying to evaluate the general factors involved, before getting coding.

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Guest Anonymous Poster
Decoding video to a texture is relatively easy, and it is just a texture so can be mapped to anything... The problem here lies with: 1) the amount of CPU effort invloved in decoding several video streams, and how are you getting all these streams? 2) the bitrate/quaility of the streams takes CPU power 3) The size (width/height/pixel format) * number of streams is the amount of data you will be sending to the graphics card each frame...

Perhaps some special/nice hardware (PCIe) or soemthing, or decoding on the GPU itself will increase your performance results.

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Quote:
Original post by Anonymous Poster
Decoding video to a texture is relatively easy, and it is just a texture so can be mapped to anything... The problem here lies with: 1) the amount of CPU effort invloved in decoding several video streams, and how are you getting all these streams? 2) the bitrate/quaility of the streams takes CPU power 3) The size (width/height/pixel format) * number of streams is the amount of data you will be sending to the graphics card each frame...

Perhaps some special/nice hardware (PCIe) or soemthing, or decoding on the GPU itself will increase your performance results.


Also, I'm not sure about the "moving as if you are there" part since cameras give you a 2d texture type data(this you know) so how will you get 3d triangle data from it?

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At this point in time I'll settle with looking from inside of a cube and mediocre performance. Future iterations would probably need a camera with a fish-eye lense, mapping onto a sphere and extra image processing. If I don't start somewhere I'll never start at all :)

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