Hanting Lu and Kedari Elety, students in Cornell University’s Electrical and Computer Engineering, have written a detailed explanation of their Hand tracking pong project, a pong game which was controlled by tracking the player’s hand:
"The NTSC video signal from the camera is stored in the SDRAM at the rate of the TV Decoder Line clock (TD_CLK). Data is read from the SDRAM each time the VGA requests data. The data from the SDRAM is in YUV format which needs to be converted to RGB before sending it to the VGA. For skin detection, we added a filter at this converting module level such that in addition to the R,G and B values, the module also outputs a one bit binary 1 if it corresponds to a skin pixel. Else, zero. By doing this, the output on the VGA is now white corresponding to skin pixels and black otherwise"