我想知道是否有可能在Python中使用OpenCV的
VideoWriter
类来 "流 "数据?
通常我使用BytesIO (或StringIO)来处理内存中的数据,否则就会进入磁盘。
但我尝试使用BytesIO时失败了。
import cv2
from io import BytesIO
stream = cv2.VideoCapture(0)
fourcc = cv2.VideoWriter_fourcc('x264')
data = BytesIO()
# added these to try to make data appear more like a string
data.name = 'stream.{}'.format('av1')
data.__str__ = lambda x: x.name
try:
video = cv2.VideoWriter(data, fourcc=fourcc, fps=30., frameSize=(640, 480))
start = data.tell()
# Check if camera opened successfully
if (stream.isOpened() == False):
print("Unable to read camera feed", file=sys.stderr)
exit(1)
# record loop
while True:
_, frame = stream.read()
video.write(frame)
data.seek(start)
# do stuff with frame bytes
# ...
data.seek(start)
finally:
try:
video.release()
except:
finally:
stream.release()
但是我没有写出BytesIO
对象,而是出现了以下信息。
Traceback (most recent call last):
File "video_server.py", line 54, in talk_to_client
video = cv2.VideoWriter(data, fourcc=fourcc, fps=fps, frameSize=(width, height))
TypeError: Required argument 'apiPreference' (pos 2) not found
...所以当我把VideoWriter的调用修改为cv2.VideoWriter(data, apiPreference=0, fourcc=fourcc, fps=30., frameSize=(640, 480))
(我读到0意味着自动,但我也试过cv2.CAP_FFMPEG
),我反而得到以下错误。
Traceback (most recent call last):
File "video_server.py", line 54, in talk_to_client
video = cv2.VideoWriter(data, apiPreference=0, fourcc=fourcc, fps=fps, frameSize=(width, height))
TypeError: bad argument type for built-in operation
所以我的问题是,是否可以在内存中使用cv2.VideoWriter
类来写编码视频,如果可以的话,是怎么写的?
在这一点上,我没有什么想法,所以任何帮助都是非常受欢迎的 :-)