from collections import deque

def flood_fill_bfs(image, sr, sc, color):
    if not image or not image[0]:
        return image
    original = image[sr][sc]
    if original == color:
        return image
    rows, cols = len(image), len(image[0])
    queue = deque([(sr, sc)])
    image[sr][sc] = color
    while queue:
        r, c = queue.popleft()
        for dr, dc in ((1,0),(-1,0),(0,1),(0,-1)):
            nr, nc = r + dr, c + dc
            if 0 <= nr < rows and 0 <= nc < cols and image[nr][nc] == original:
                image[nr][nc] = color
                queue.append((nr, nc))
    return image