zibad.blogg.se - Ffmpeg python linux image2pipe

In the sample video, the key length is 16 bytes, but it is not guaranteed. Presumably in a separate specification document you would agree on a key length for a given application. Keys can be 1, 2, 4, or 16 bytes in length.

Data reader thread - read and parse KLV data.Īccording to Wikipedia, the KLV format is not well defined:.

Video reader thread - read raw video frames (in BGR) format.

The video and the data are read in two separate threads: Suggested way for splitting the video and the data:. We may still apply some coarse synchronization - assume the data and the frame are read in time proximity. The Day Flight.mpg sample file has much fewer data packets than frames, and accurate synchronization is not possible using the suggested solution (I don't think it is possible using the pipes approach). The same technique is used for separating video and audio in my following answer.Īccurate synchronization between the the video frame and the corresponding data is relatively simple when each video frame has private KLV data (synchronize by sequential order).

Produces the below error: Traceback (most recent call last):ĪttributeError: 'UnknownElement' object has no attribute 'MetadataList'įor splitting the video and data, we may map the video stream to stderr pipe and map the KLV data stream to to stdout pipe. Image = omstring(raw_image, dtype='uint8')įor packet in klvdata.StreamParser(pipe.stdout): Pipe = sp.Popen(command, stdin=sp.PIPE, stdout=sp.PIPE, stderr=sp.PIPE, bufsize=10**8)

My problem is I cannot figure out how to map both the video and klvdata to the same subprocess pipe simultaneously?

I pass the data to OpenCV with the subprocess module. I'm using FFMPEG to read the file or stream as OpenCV does not retain the klvdata. I need to process the video stream and the klvdata streams simultaneously in real-time in OpenCV/Python.