Fixing gamma correction issue. Add a debug view mode.
Fixing gamma correction issue. Add a debug view mode.

unrealcv/unrealcv,qiuwch/unrealcv,qiuwch/unrealcv,unrealcv/unrealcv,qiuwch/unrealcv,qiuwch/unrealcv,unrealcv/unrealcv,unrealcv/unrealcv,qiuwch/unrealcv,qiuwch/unrealcv,unrealcv/unrealcv