About System and Elementary Streams

You can use Compressor to create system or elementary MPEG-1 streams.

System Streams

System streams, also known as multiplexed streams, combine the video and audio components into the same file. This type of stream is most often used in web applications.

Compressor automatically creates a system stream when you enable both the Video and Audio tabs in the same setting.

Elementary Streams

With elementary streams, there are separate files for the video and audio components. Elementary streams are required by some applications.

Compressor automatically creates an elementary stream when only the Video or Audio tab is enabled, but not both. To create elementary streams of both the video and the audio, you must use two settings—one with the Video tab enabled using the file extension of .m1v and a second with the Audio tab enabled using the file extension of .m1a.