Initial commit

.tmp_axprobe/diff3.swift

@@ -0,0 +1,40 @@
+import Foundation
+func load(_ path: String) -> (Data, Int, Int, Int, Int) {
+    let d = try! Data(contentsOf: URL(fileURLWithPath: path))
+    let pixOff = Int(d.withUnsafeBytes { $0.load(fromByteOffset: 10, as: UInt32.self) })
+    let w = Int(d.withUnsafeBytes { $0.load(fromByteOffset: 18, as: Int32.self) })
+    let hRaw = Int(d.withUnsafeBytes { $0.load(fromByteOffset: 22, as: Int32.self) }); let h = abs(hRaw)
+    let B = Int(d.withUnsafeBytes { $0.load(fromByteOffset: 28, as: UInt16.self) })/8
+    let rb = (B*w+3) & ~3
+    return (d, pixOff, w, h, hRaw > 0 ? 1 : 0) // 1 = bottom-up
+}
+let (A, poA, w, h, flipA) = load("new.bmp")
+let (B2, poB, _, _, flipB) = load("after3.bmp")
+let rb = (4*w+3) & ~3
+let BS = 45
+var blocks: [(Int,Int,Int)] = []
+var y = 0
+while y < h { var x = 0
+  while x < w {
+    var diff = 0
+    var yy = y; while yy < min(y+BS, h) {
+      let ra = poA + (flipA==1 ? (h-1-yy) : yy) * rb
+      let rb2 = poB + (flipB==1 ? (h-1-yy) : yy) * rb
+      var xx = x; while xx < min(x+BS, w) {
+        let ia = ra + xx*4, ib = rb2 + xx*4
+        let dr = abs(Int(A[ia+2]) - Int(B2[ib+2]))
+        let dg = abs(Int(A[ia+1]) - Int(B2[ib+1]))
+        let db = abs(Int(A[ia]) - Int(B2[ib]))
+        if dr+dg+db > 60 { diff += 1 }
+        xx += 2
+      }
+      yy += 2
+    }
+    if diff > 8 { blocks.append((x,y,diff)) }
+    x += BS
+  }
+  y += BS
+}
+print("changed blocks (x,y,diffPx):")
+for b in blocks { print("  x=\(b.0)-\(b.0+BS) y=\(b.1)-\(b.1+BS) px=\(b.2)") }
+if blocks.isEmpty { print("  none") }