Never mind, just when I posted this I fixed the problem.
Sorry again, Nicolas.
Umm .. not sure. Maybe remove the FlushMem, I don't see any reason why you would want to do that.
Also, to flip an image, you can use SetScale with negative values such as SetScale -1,1 should flip an image horizontally. You can just convert the pixmap to an image and use the scaling-flip and then DrawImage.
But I know you're not exactly just trying to do that. I don't see why you would be getting a crash ... and the reason it is slow is because you are accessing a lot of individual pixels, plus you are working in main memory - might depent on the speed of you computer. You also put a delay in there, of course it will pause.
It was the FlushMem...
But still the program is really slow, it's not the delay, when you read/write the pixels in/out it takes about four to five seconds before it shows the image. That's long even for that many pixels and the hardware that it's running on. Any thoughts to make it go faster?
Sorry again, Nicolas.