MediaMuxer expert required

Create a "test" app that uses MediaMuxer to process a 100 MB video file in 10 seconds or less. The processing time must be 10 seconds or less, and the video quality must still be OK. I will supply the 100 MB file. Input: [login to view URL] dimensions: 1920x1080 file size: 100 MB duration: 10 seconds Output: [login to view URL] dimensions: 640x360 file size: around 10 MB duration: 10 seconds Note: I have experimented with FFMPEG for the video processing, and it takes 4 minutes to process this file, which is not acceptable for the user to wait that long, when the video duration is only 10 seconds - the user will expect processing time to be 10 seconds or less.