VP510

The VP510 converts three channels of RGB data into twochannels of decimated chrominance and luminance data.Alternatively VP510 converts two channels of  luminance and chromi-nance data into three channels of interpolated RGB data.Each channel has its own RAM based look up table, which canbe loaded from a host system and then used for gammacorrection and/or ranging.

The direction of the VP510 data flow is controlled by a bit in aControl Register, and causes previous outputs to becomeinputs and vice versa. The filters change from the decimatingto the interpolating mode, and correspondingly follow orprecede the colour space conversion.

The 3 x 3 conversion matrix is provided with user definable12 bit coefficients which have a range from -4.0 to +4.0. Theluminance channel is provided with a 23 tap low pass filterwhich can decimate or interpolate by two. The chrominancechannels each have two 11 tap filters in series which candecimate or interpolate by four. This arrangement allows the VP510 device to accept or produce RGB data which has been 2xoversampled, thus avoiding the need for external analog anti-aliasing filters. If necessary the device will still accept orproduce video data which has not been oversampled.