VCG is an integrated VGA Graphics and Video Capture card combining
a 1024 x 768 pixel VGA and an image capture at up to 768 x 576 pixels.
For colour display, the image is converted to RGB and under
control of the Video Capture Controller is transferred into the
parallel port of the Video Image VRAM. The Video Image is treated in
this design as a linear pixel array starting at the top left of the
rastered input and ending with the bottom right. The input control
also manages the conversion of the interlaced input to a
non-interlaced frame available for display at the display rate. By
this means a complete PAL image of 768 by 576 pixels can be stored in
the capture memory.
The scaler can also be configured to deliver YUV to the capture
memory and in this case the output can be set to 5 bit monochrome for
display. Full 8 bits of Y values are available in capture memory for
processing purposes.
