how to create and run video at the same time.

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I need help. Thank you for your understanding though it seems to be challenging because it is a question through a translator.

Contents.

I'm implementing video color conversion using opencv 3.2.0 / java (spring boot).

The process.

• After uploading the video to the server, extract the color of the frame and send the color data to the client.
• Send color data to the server to change the extracted color data to the color desired by the user.
• Split the uploaded video into frames and convert the colors.
• Reconstructs separated frames into video.
• When the movie is finished, it runs on the client.

It takes a long time for the color to be converted and created as a video.

At this time, the user can not know the progress, but after the video creation is finished, it is not executed until it is executed on the client.

So I want to implement the video to be played on the client at the same time as I create it so I can see the progress.

*I want to show the video creation process on the client.*

Please share your knowledge or implementation method.

PS. I tried to run the video file I was creating before "videoWriter.release ();" was called, but it did not work.