From the site: Developers When would I need to decode AC-3? Playing most live TV content Playing most recorded TV content Playing many videos from

From the site: Developers When would I need to decode AC-3? Playing most live TV content Playing most recorded TV content Playing many videos from DVD Playing many videos from Blu-Ray Playing videos recorded by some digital camcorders Playing some online streaming content offered in 5.1 surround sound When would I need to encode AC-3? Hopefully never! In practice, there are a few cases: Encoding surround sound audio for some legacy TVs and devices that only support AC-3 for surround. Modern devices can decode other multichannel formats such as AAC, DTS, and Opus. Encoding surround sound audio to be sent to a legacy AV receiver using an optical cable (S/PDIF). Modern AV receivers can accept other formats over HDMI, including multichannel PCM. Is AC-3 any good? Should I use it for new stuff? No, of course not. AC-3 is over 25 years old and horribly inefficient.