Colour-Space Converter

The CSC IP Core is a fully pipelined colour-space converter that converts pixels between the RGB and YCbCr colour spaces. In total, the IP Core package contains two distinct modules – one module that converts from 24-bit RGB to 30-bit 4:4:4 YCbCr and the other that performs the reciprocal operation from 4:4:4 YCbCr to RGB.

Pixels flow into the design in accordance with the valid ready pipeline protocol1. Input pixels and syncs are sampled on the rising edge of clk when pixin_val and pixin_rdy are both high. At the output interface, pixels and syncs are sampled on a the rising edge of clk when pixout_val and pixout_rdy are high. The input and output sync signals are sideband flags that are coincident with the first pixel of a frame and the first pixel of a line. These are useful to identify the video frame and line boundaries and are included for compatibility with the rest of Zipcores video IP.

Note that if no flow control is required in the design and the output interface can always accept pixels, then the pixout_rdy signal may be tied high. Likewise, the pixin_rdy flag may be ignored in this case.

• Synthesizable, technology independent VHDL IP Core
• Conversion of pixels between RGB and YCbCr colour spaces
• Supports 24-bit RGB888 and 30-bit YCbCr 4:4:4 formats
• Fully pipelined architecture with simple flow control
• Features VSYNC and HSYNC sideband flags to keep track of video frame and line boundaries
• Output 1 x pixel per clock
• Small implementation size
• Support for 400 MHz+ operation on basic FPGA devices

• Digital video and image processing
• Interfacing between different video processing and video transceiver ICs that use different colour spaces