Bilinear Video Scaling Engine

XY2_SCALER is a very high quality video scaler capable of generating interpolated output images from 16x16 up to 216 x 216 pixels in resolution. The architecture permits seamless scaling (either up or down) depending on the chosen scale factor. Internally, the scaler uses a 24-bit accumulator and a bank of polyphase FIR filters with 16 phases or interpolation points. All filter coefficients are programmable, allowing the user to define a wide range of filter characteristics.

Pixels flow in and out of the scaling engine in accordance with the valid ready pipeline protocol. Pixels are transferred into the scaler on a rising clock-edge when pixin_val is high and pixin_rdy is high. Likewise, pixels are transferred out of the scaler on a rising clock-edge when pixout_val is high and pixout_rdy is high. As such, the pipeline protocol allows both input and output interfaces to be stalled independently.

• Synthesizable, technology independent VHDL IP Core
• Versatile 24-bit RGB/YCbCr video scaler capable of scaling up or down by any factor. Different pixel formats supported on request
• 24-bit accumulator with 24-bit scale-pitch in [24 12] format
• Supports all video resolutions between 16x16 and 2¹⁶x 2¹⁶ pixels
• Fully pipelined architecture with simple flow control
• Features a 2x2 polyphase filter in the x and y dimensions. Each filter has 16 unique phases or interpolation points
• Fully programmable filter coefficients to suit the desired application
• Example bilinear coefficients shipped with the design
• Output rate is 1 x 24-bit pixel per clock for scaling factors > 1
• Generates one scaled output frame for every input frame
• No frame buffer required
• Supports 250MHz+ operation on basic FPGA devices

• High quality 24-bit RGB/YCbCr video scaling
• Conversion of popular video formats to any other resolution  such as VGA to XGA, SVGA to HD1080 etc.
• Digital TV set-top boxes and home media solutions
• Conversion to non-standard video resolutions - e.g. for use in portable devices and flat-panel displays
• Dynamic scaling of video in a window on a frame-by-frame basis
• Picture in Picture (PiP) applications