phase 4

core/gpu/models/cv/segmentation.py

@@ -0,0 +1,86 @@
+"""
+Field segmentation — HSV green mask → pitch boundary contour.
+
+Pure OpenCV. Called by the inference server endpoint.
+"""
+
+from __future__ import annotations
+
+import base64
+
+import cv2
+import numpy as np
+
+
+def segment_field(
+    image: np.ndarray,
+    hue_low: int = 30,
+    hue_high: int = 85,
+    sat_low: int = 30,
+    sat_high: int = 255,
+    val_low: int = 30,
+    val_high: int = 255,
+    morph_kernel: int = 15,
+    min_area_ratio: float = 0.05,
+) -> dict:
+    """
+    Detect the pitch area using HSV green thresholding.
+
+    Returns dict with:
+        boundary: list of [x, y] points
+        coverage: float (fraction of frame)
+    """
+    hsv = cv2.cvtColor(image, cv2.COLOR_RGB2HSV)
+
+    lower = np.array([hue_low, sat_low, val_low])
+    upper = np.array([hue_high, sat_high, val_high])
+    mask = cv2.inRange(hsv, lower, upper)
+
+    k = morph_kernel
+    kernel = cv2.getStructuringElement(cv2.MORPH_ELLIPSE, (k, k))
+    mask = cv2.morphologyEx(mask, cv2.MORPH_CLOSE, kernel)
+    mask = cv2.morphologyEx(mask, cv2.MORPH_OPEN, kernel)
+
+    contours, _ = cv2.findContours(mask, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
+
+    h, w = image.shape[:2]
+    min_area = min_area_ratio * h * w
+    boundary = []
+    coverage = 0.0
+
+    if contours:
+        large = [c for c in contours if cv2.contourArea(c) >= min_area]
+        if large:
+            pitch_contour = max(large, key=cv2.contourArea)
+            boundary = pitch_contour.reshape(-1, 2).tolist()
+            coverage = cv2.contourArea(pitch_contour) / (h * w)
+
+            refined = np.zeros_like(mask)
+            cv2.drawContours(refined, [pitch_contour], -1, 255, cv2.FILLED)
+            mask = refined
+
+    return {
+        "boundary": boundary,
+        "coverage": coverage,
+        "mask": mask,
+    }
+
+
+def segment_field_debug(
+    image: np.ndarray,
+    **kwargs,
+) -> dict:
+    """Same as segment_field but includes a mask overlay for the editor."""
+    result = segment_field(image, **kwargs)
+    mask = result["mask"]
+
+    # RGBA overlay: solid green where mask, fully transparent elsewhere
+    h, w = image.shape[:2]
+    overlay = np.zeros((h, w, 4), dtype=np.uint8)
+    overlay[mask > 0] = [0, 255, 0, 255]
+    _, buf = cv2.imencode(".png", overlay)
+    result["mask_overlay_b64"] = base64.b64encode(buf.tobytes()).decode()
+
+    # Don't send the raw mask over HTTP
+    del result["mask"]
+    return result