LockedPixels are faster because Blitz gives you direct access to the block of memory used for the buffer (in the form of a bank). The downside to this is that you have to work out what pixel format is used in that memory block and adjust it to whatever you want to do with it. Complicated but not that complicated.
Read/WritePixelfast on the other hand do all that work for you. That is also why it is slower.
Read/WritePixelfast on the other hand do all that work for you. That is also why it is slower.