pub fn quantize(coeffs: &[i32; 16], qp: u8, dz_div: i64) -> [i32; 16]Expand description
Quantizes forward-transform coefficients to levels. intra selects the
rounding dead-zone offset (1/3 for intra, 1/6 for inter).
Scalar quantization. dz_div sets the rounding dead-zone: the offset added
before the right shift is 2^qbits / dz_div, so a smaller dz_div rounds
up more (higher quality, more bits). Typical values: 6 for inter, 3 for an
I-frame that serves as a reference, 2 for all-intra (where the larger offset
is a net rate-distortion win — better-quantized blocks predict their
neighbors better, shrinking downstream residuals).