doc: readme with community QR code (#67)

scripts/crop_qr.py

@@ -0,0 +1,54 @@
+
+import os
+from PIL import Image, ImageChops
+
+def trim_whitespace(im):
+    bg = Image.new(im.mode, im.size, im.getpixel((0,0)))
+    diff = ImageChops.difference(im, bg)
+    diff = ImageChops.add(diff, diff, 2.0, -100)
+    bbox = diff.getbbox()
+    if bbox:
+        return im.crop(bbox)
+    return im
+
+def process_image(path):
+    try:
+        img = Image.open(path)
+        img = img.convert("RGBA")
+        
+        # Simple trim of uniform background
+        cropped = trim_whitespace(img)
+        
+        # If the image is a "photo", simple trim might not work if lighting is uneven.
+        # But let's assume digital image for now based on typical user behavior.
+        # Function to find the QR code area more robustly:
+        # Convert to grayscale, threshold, invert, find bbox of black pixels.
+        gray = img.convert("L")
+        # Threshold: anything darker than 200 is "black" (QR code), else white
+        bw = gray.point(lambda x: 0 if x < 200 else 255, '1')
+        # Invert to make QR code white on black background for getbbox
+        bw_inv = ImageChops.invert(bw)
+        bbox = bw_inv.getbbox()
+        
+        if bbox:
+            # Add a small padding
+            left, upper, right, lower = bbox
+            width, height = img.size
+            left = max(0, left - padding)
+            upper = max(0, upper - padding)
+            right = min(width, right + padding)
+            lower = min(height, lower + padding)
+            cropped = img.crop((left, upper, right, lower))
+        
+        cropped.save(path)
+        print(f"Processed {path}")
+    except Exception as e:
+        print(f"Error processing {path}: {e}")
+
+assets_dir = "src/assets/community"
+for filename in ["feishu-qr.png", "wecom-qr.png"]:
+    file_path = os.path.join(assets_dir, filename)
+    if os.path.exists(file_path):
+        process_image(file_path)
+    else:
+        print(f"File not found: {file_path}")