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Optimize co-occurence matrix

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Kornel 2024-03-26 15:23:16 +00:00 committed by andrews05
parent 36de54318d
commit a3590df20c
1 changed files with 9 additions and 5 deletions
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14
src/reduction/palette.rs
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@ -201,14 +201,18 @@ fn most_popular_edge_color(num_colors: usize, png: &PngImage) -> usize {
}
// Calculate co-occurences matrix
fn co_occurrence_matrix(num_colors: usize, png: &PngImage) -> Vec<Vec<usize>> {
let mut matrix = vec![vec![0; num_colors]; num_colors];
fn co_occurrence_matrix(num_colors: usize, png: &PngImage) -> Vec<Vec<u32>> {
let mut matrix = vec![vec![0u32; num_colors]; num_colors];
let mut prev: Option<ScanLine> = None;
let mut prev_val = None;
for line in png.scan_lines(false) {
for i in 0..line.data.len() {
let val = line.data[i] as usize;
if i > 0 {
matrix[line.data[i - 1] as usize][val] += 1;
if val > num_colors {
continue;
}
if let Some(prev_val) = prev_val.replace(val) {
matrix[prev_val][val] += 1;
}
if let Some(prev) = &prev {
matrix[prev.data[i] as usize][val] += 1;
@ -220,7 +224,7 @@ fn co_occurrence_matrix(num_colors: usize, png: &PngImage) -> Vec<Vec<usize>> {
}
// Calculate edge list sorted by weight
fn weighted_edges(matrix: &[Vec<usize>]) -> Vec<(usize, usize)> {
fn weighted_edges(matrix: &[Vec<u32>]) -> Vec<(usize, usize)> {
let mut edges = Vec::new();
for i in 0..matrix.len() {
for j in 0..i {