Function sample_grid_generic 

pub fn sample_grid_generic<S: DecodingStrategy>(
    img: &ImageView<'_>,
    homography: &Homography,
    decoder: &(impl TagDecoder + ?Sized),
) -> Option<S::Code>

Sample the bit grid from the image using the homography and decoder points.

Uses bilinear interpolation for sampling and a spatially adaptive threshold (based on min/max stats of the grid) to determine bit values.

Parameters

• min_contrast: Minimum contrast range for Otsu-based classification. Default is 20.0. Lower values (e.g., 10.0) improve recall on small/blurry tags.

This computes the intensities at sample points and the adaptive thresholds, then delegates to the strategy to produce the code.