Creating Dolby Digital Professional Output Files

Compressor provides the tools you need to encode, and batch-encode, Dolby Digital Professional (AC-3) audio files.

Dolby Digital Professional format (also known as AC-3) is a very common compressed audio format for DVD-Video discs. Compressor accepts multichannel sound files in a variety of formats and gives you complete control over the AC-3 encoding process. Dolby Digital programs can deliver 5.1-channel surround sound with five discrete full-range channels (left, center, right, left surround, and right surround) plus a sixth channel for low-frequency effects (LFE), sometimes known as “the subwoofer.” Another surround option is Dolby Surround, with four channels (left, center, right, surround). But not all AC-3 audio is 5.1 surround sound. Dolby Digital Professional is commonly used to encode stereo files to greatly reduce their file size.

Note: Dolby Digital Professional encoding with Compressor is available only on computers that also have Final Cut Studio installed. If you are using Compressor with distributed processing, Final Cut Studio must be installed on each node that will be doing Dolby Digital Professional encoding.

See the Soundtrack Pro User Manual for comprehensive information about creating surround sound audio files. If you are planning to make DVDs using DVD Studio Pro, see the DVD Studio Pro User Manual for more information about the DVD authoring workflow. See Adding Image Sequences to Batches for more information about creating surround sound audio files using other output formats.

Note: It’s important to understand that Compressor cannot take stereo audio files and create 5.1 surround sound from them. If you want to create a 5.1 surround sound AC-3 audio file, you must first create the six channels of audio it requires. This must be done using other applications, such as Soundtrack Pro, outside Compressor.