Create scale.ts

main/src/vision/opencv/cpp/scale.ts

@@ -0,0 +1,77 @@
+import type * as cv from "@u4/opencv4nodejs";
+import {
+  createBgMask,
+  filterMultiple,
+  getTomeBg,
+  getTomePxSize,
+} from "./utils";
+import {
+  FINE_TUNE_SCALES,
+  ULTRA_FINE_TUNE_SCALES,
+  USUAL_SCALES,
+} from "../constants";
+
+function bestScale(
+  img: cv.Mat,
+  needle: cv.Mat,
+  originalH: number,
+  scales: number[],
+  threshold: number,
+  startingScale = 1,
+) {
+  let bestScale = startingScale;
+  let bestFound: cv.Rect[] = [];
+  for (const testScale of scales) {
+    const size = getTomePxSize(testScale, originalH);
+
+    const scaledNeedle = needle.resize(size, size);
+    const mask = createBgMask(size);
+    const found = filterMultiple(
+      img,
+      scaledNeedle,
+      threshold,
+      size,
+      size,
+      mask,
+    );
+    if (found.length > bestFound.length) {
+      bestScale = testScale;
+      bestFound = found;
+    }
+  }
+  return { scale: bestScale, rects: bestFound };
+}
+
+export function getImageScale(img: cv.Mat, original: { w: number; h: number }) {
+  const needle = getTomeBg();
+  const { scale: firstScale, rects: firstRects } = bestScale(
+    img,
+    needle,
+    original.h,
+    USUAL_SCALES,
+    0.65,
+  );
+  console.log(`First scale guess: ${firstScale} [${firstRects.length}]`);
+
+  const { scale: secondScale, rects: secondRects } = bestScale(
+    img,
+    needle,
+    original.h,
+    FINE_TUNE_SCALES.map((s) => firstScale + s / 100),
+    0.75,
+    firstScale,
+  );
+  console.log(`Second scale guess: ${secondScale} [${secondRects.length}]`);
+
+  const { scale: thirdScale, rects: thirdRects } = bestScale(
+    img,
+    needle,
+    original.h,
+    ULTRA_FINE_TUNE_SCALES.map((s) => secondScale + s / 100),
+    0.8,
+    secondScale,
+  );
+  console.log(`Third scale guess: ${thirdScale} [${thirdRects.length}]`);
+
+  return thirdScale;
+}