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perf(scanner): drop two full-frame adaptive thresholds that nothing reads #1307

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Merged
bmc08gt merged 1 commit into from
Aug 22, 2026
Merged

perf(scanner): drop two full-frame adaptive thresholds that nothing reads #1307

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17 changes: 0 additions & 17 deletions vendor/kik/scanner/src/main/cpp/scan/scanner.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -417,23 +417,6 @@ bool detectKikCode(Mat &greyscale, Mat *out_progress, uint32_t device_quality, u
Mat whitish;
Mat blackish;

// --- START OF EDIT ---
// we switch to an inverted scheme (dark is high, light is low) if the
// center ellipse is dark, but we don't want to compute the extra threshold everytime
// so we only do this when needed.
//
// Using adaptive thresholding is more robust to lighting changes than a global threshold.
// It calculates a threshold for smaller regions, making it less susceptible to shadows or glare.
// A block size of 11 or higher is a good starting point and must be an odd number.
// The constant 'C' (here, 5) is subtracted from the mean, which helps in finding features.

// For finding dark features on a light background.
adaptiveThreshold(greyscale, blackish, 255, ADAPTIVE_THRESH_GAUSSIAN_C, THRESH_BINARY_INV, 21, 5);

// For finding light features on a dark background.
adaptiveThreshold(greyscale, whitish, 255, ADAPTIVE_THRESH_GAUSSIAN_C, THRESH_BINARY, 21, 5);
// --- END OF EDIT ---

// we switch to an inverted scheme (dark is high, light is low) if the
// center ellipse is dark, but we don't want to compute the extra threshold everytime
// so we only do this when necessary
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