Patent ID: 8924207

Claim:
A method of an AC-3 audio encoder for transcoding audio data, the method comprising: performing, by a processor, operations comprising: parsing an AAC bitstream in order to determine whether an AAC joint stereo mode is enabled, wherein the AAC bitstream comprises data relating to AAC bands; determining whether each band of the AAC bands has joint stereo and determining whether each band of the AAC bands is an AAC scale factor band; when the AAC joint stereo mode is enabled and when the number of the AAC bands determined to have joint stereo is greater than half of the number of the AAC scale factor bands, enabling a rematrixing mode and rematrixing the AC-3 audio encoder; and when the AAC joint stereo mode is disabled and when the number of the AAC bands determined to have joint stereo is less than or equal to half the number of the AAC bands determined to be AC scale factor bands, performing reference AC-3 rematrixing in order to determine a status of the rematrixing mode.