add RLE compression of masks in python

src/main/java/ai/nets/samj/models/PythonMethods.java

@@ -100,6 +100,47 @@ public class PythonMethods {
 			+ "globals()['trace_contour'] = trace_contour" +  System.lineSeparator()
 			+ "globals()['get_polygons_from_binary_mask'] = get_polygons_from_binary_mask" +  System.lineSeparator();
 
+	/**
+	 * String containing a Python method to encode binary masks into a compressed object using the
+	 * Run-Length Encoding (RLE) algorithm
+	 */
+	protected static String RLE_METHOD = ""
+			+ "def encode_rle(mask: Union[np.ndarray, List[List[int]]]) -> List[int]:" +  System.lineSeparator()
+			+ "    \"\"\"" +  System.lineSeparator()
+			+ "    Encode a binary mask using Run-Length Encoding (RLE)." +  System.lineSeparator()
+			+ "    " +  System.lineSeparator()
+			+ "    Args:" +  System.lineSeparator()
+			+ "        mask: A 2D binary array (numpy array or list of lists) where 1 represents the object" +  System.lineSeparator()
+			+ "             and 0 represents the background" +  System.lineSeparator()
+			+ "    " +  System.lineSeparator()
+			+ "    Returns:" +  System.lineSeparator()
+			+ "        List[int]: RLE encoding in the format [start1, length1, start2, length2, ...]" +  System.lineSeparator()
+			+ "                  where start positions are 0-based" +  System.lineSeparator()
+			+ "    \"\"\"" +  System.lineSeparator()
+			+ "    if isinstance(mask, list):" +  System.lineSeparator()
+			+ "        mask = np.array(mask)" +  System.lineSeparator()
+			+ "    " +  System.lineSeparator()
+			+ "    # Flatten the mask in row-major order" +  System.lineSeparator()
+			+ "    binary = mask.flatten()" +  System.lineSeparator()
+			+ "    " +  System.lineSeparator()
+			+ "    # Find positions where values change" +  System.lineSeparator()
+			+ "    transitions = np.where(binary[1:] != binary[:-1])[0] + 1" +  System.lineSeparator()
+			+ "    transitions = np.concatenate(([0], transitions, [len(binary)]))" +  System.lineSeparator()
+			+ "    " +  System.lineSeparator()
+			+ "    # Initialize result" +  System.lineSeparator()
+			+ "    rle = []" +  System.lineSeparator()
+			+ "    " +  System.lineSeparator()
+			+ "    # Process each run" +  System.lineSeparator()
+			+ "    for i in range(len(transitions) - 1):" +  System.lineSeparator()
+			+ "        start = transitions[i]" +  System.lineSeparator()
+			+ "        length = transitions[i + 1] - transitions[i]" +  System.lineSeparator()
+			+ "        " +  System.lineSeparator()
+			+ "        # Only encode runs of 1s" +  System.lineSeparator()
+			+ "        if binary[start] == 1:" +  System.lineSeparator()
+			+ "            rle.extend([start, length])" +  System.lineSeparator()
+			+ "    " +  System.lineSeparator()
+			+ "    return rle" +  System.lineSeparator();
+
 
 	protected static String SAM_EVERYTHING = ""
 			+ "def calculate_pairs(masks):\n"