If conceptually possible, video processing IP should offer an optional built-in test-pattern generator to temporarily feed the output AXI4-Stream master interface with a predefined pattern.
Use Flag TEST_PATTERN , located on bit 5 of the CONTROL register to turn test-pattern generation on (1) or off. This switch can control multiplexers driving the AXI4-Stream master output and switch between the regular core processing output and the test-pattern generator. When enabled, a set of counters should generate 256 scan-lines of color-bars, each color bar 64 pixels wide, repetitively cycling through the colors Black, Red, Green, Yellow, Blue, Magenta, Cyan, and White until the end of each scan line. After the Color-Bars segment is processed, the remainder of the frame should be filled with a monochrome horizontal + vertical ramp.