photoshop 3d piano

I opened image of piano with photoshop and droped it in 2 layers. Named those two layers blue and red. Then selected layer called blue and modified curves by selecting channel to red and pressing about in the middle of the line and changing output to 0 and input to 225 then I did almost the same to red layer the only difference was that i changed it 2 times.First time I selected channel called green and after that did the same with blue channel then moved a top layer slightly so that two layers would overlap. And the final result was 3d image witch you could see after putting on 3d glasses.]