Python | OpenCV 資料蒐集

# download_images.py
from icrawler.builtin import BingImageCrawler

crawler = BingImageCrawler(storage={"root_dir": "dataset/cat"})
crawler.crawl(keyword="cat", max_num=200)

# capture_from_camera.py
import cv2
import os

save_dir = "dataset/camera"
os.makedirs(save_dir, exist_ok=True)

cap = cv2.VideoCapture(0)
if not cap.isOpened():
    print("❌ 無法開啟攝影機")
    exit()
count = 0

print("按下空白鍵拍照，按 q 離開")

while True:
    ret, frame = cap.read()
    if not ret:
        break

    cv2.imshow("Capture", frame)
    key = cv2.waitKey(1) & 0xFF

    if key == ord(' '):
        filename = os.path.join(save_dir, f"{count:04d}.jpg")
        cv2.imwrite(filename, frame)
        print(f"已儲存：{filename}")
        count += 1
    elif key == ord('q'):
        break

cap.release()
cv2.destroyAllWindows()

# extract_frames.py
import cv2
import os

video_path = "assets/highway.mp4"
save_dir = "dataset/car"
os.makedirs(save_dir, exist_ok=True)

cap = cv2.VideoCapture(video_path)
if not cap.isOpened():
    print(f"❌ 無法開啟影片：{video_path}")
    exit()
frame_interval = 10  # 每隔 10 幀截取一張
count = 0
saved = 0

while True:
    ret, frame = cap.read()
    if not ret:
        break
    if count % frame_interval == 0:
        filename = os.path.join(save_dir, f"{saved:04d}.jpg")
        cv2.imwrite(filename, frame)
        saved += 1
    count += 1

cap.release()
print(f"共截取 {saved} 張影格")