cb_rec709Check (Compatible with IFFS 2025.0.0 and up)
Validates Rec709 color and luma values with waveform overlay.
front - Input image
lumaThreshold - Sensitivity for illegal luma detection
chromaThreshold - Sensitivity for illegal chroma detection
highlightStrength - Strength of illegal value highlighting
showWaveform - Toggle waveform display
waveformHeight - Height of waveform overlay
waveformOpacity - Opacity of waveform overlay
resolution - Image resolution (width, height)
Illegal Rec709 Value Calculation:
Conversion: RGB to YCbCr using Rec709 coefficients (Y = luma, Cb/Cr = chroma).
Legal Ranges: Luma: 16/255 to 235/255; Chroma: 16/255 to 240/255.
Check: Illegal if Y, Cb, or Cr exceeds range ± threshold.
Intensity: Measures violation distance beyond range, scaled by threshold, clamped 0-1.
Visualization: Red for luma, green for chroma, yellow for both; waveform shows luma with illegal in red.
Version notes
Check rec709 illegal values. cb@barefootvfx.com.au
Older versions that shader
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