[mwtidd]

I personally wouldn't try to see the color specifically but rather the brightness. You could align your robot left or right of the center of the goal, but in a position that the camera can see both the left and right sides of the I. With some pretty simple brightness filters, you should be able to detect if your side or the other side is hotter.

If you are only using this to detect hotness, then I would also align the camera so the target is in the top portion of your view, that way you can filter out the lower section. Given you have a line for alignment you may even want to filter out some of the area in the middle of the goal to avoid noise from the crowd etc.

If you're using rgb, you could use a custom threshold like minimum of rgb, or if your camera sees the yellow you could use a min average threshold of RG.

Then split you screen into three columns and calculate the average brightness of the three. If you're in the hot side two of the three should show up as hot, if you're on the cold side, only one of the three should show up hot.