ruby.rb

          command = [
            'ffmpeg',
            '-y',
            '-f', 'mpegts',
            '-i', "concat:#{@input.join('|')}",
            '-c', 'copy',
            '-bsf:a', 'aac_adtstoasc',
            '-bsf:v', 'h264_mp4toannexb',
            output_dest
          ]
          stdout_str, stderr_str, status = Open3.capture3(*command)

# generates this command:
# ffmpeg -y -f mpegts -i concat:chunks\\1.ts|chunks\\2.ts|chunks\\3.ts -c copy -bsf:a aac_adtstoasc -bsf:v h264_mp4toannexb W:/Workspace/MediaPublisherNG/videos/output.mp4

# but ffmpeg needs quotes arround concat
# ffmpeg -y -f mpegts -i "concat:chunks\\1.ts|chunks\\2.ts|chunks\\3.ts" -c copy -bsf:a aac_adtstoasc -bsf:v h264_mp4toannexb W:/Workspace/MediaPublisherNG/videos/output.mp4