Enhance PSNR Check for Luma (Y) Channel in VPP Sharpen Filter

The current implementation of the PSNR check for the Luma (Y) channel raises exceptions for actual values exceeding reference values.
This behavior is not reflective of typical processing scenarios where higher actual values are expected.

Updated the `compare` function to only raise exceptions if the actual Luma (Y) value is lower than the reference value.

Signed-off-by: Wang Hangjie <[email protected]>

Author: Hangjie22Coder

lib/mixin/vpp.py

@@ -132,7 +132,10 @@ def compare(k, ref, actual):
         assert actual[-2] == 100, "Cb(U) should not be affected by SHARPEN filter"
         assert actual[-1] == 100, "Cr(V) should not be affected by SHARPEN filter"
         assert ref is not None, "Invalid reference value"
-        assert abs(ref[-3] - actual[-3]) < 0.25, "Luma (Y) out of baseline range"
+        # Only assert if actual Luma (Y) is lower than reference, using specified range condition
+        if actual[-3] < ref[-3]:
+          # Ensure the difference is within the acceptable range [0, 0.25)
+          assert 0 <= ref[-3] - actual[-3] < 0.25, f"Luma (Y) is lower than reference value: {actual[-3]} < {ref[-3]}"
 
       metrics2.check(
         metric = dict(type = "psnr"), compare = compare,