电视方案中常用的音频名词解释.pdfVIP

WHAT IS ? or Little glossary of the terminology often used about TV sound processing prepared by Thierry MEUNIER updated on October 3, 2000 5:48 pm 1 / 16 INDICATIONS • the items are alphabetic sorted • numbers are sorted AFTER letters • a BLUE WRITTEN WORD is explained in this glossary. An hyperlink is available in softcopies. ADVERTISEMENT • The aim of this glossary is not to give deep technical details, or to explain how it works. This is more an help to recover rapidly some definitions with their main properties. If you wish more detailled explanations or datas, some bibliography are given under the sign more info ? 2 / 16 AAC • for Advance Audio Coding • is one of the audio compression formats defined by the MPEG-2 standard. • AAC is not compatible with the MPEG-1 audio formats. MPEG-2 also defined another audio format called MPEG-2 Multichannel or MPEG-2 BC (Backward Compatible), which is compatible with MPEG-1 • AAC is more efficient than MP3 more info ? /MPEG/aac.html AC3 • is for Audio Coding, 3rd generation. • encoding ( with compression) process for 1 to 5 digital audio channels, plus 1 audio channel with reduced bandwidth. • Approved by the ATSC • compression based on the PERCEPTUAL concept • the 6 channels are classically : Right, Left, Center, Surround Right, Surround Left, Woofer • full bandwidth ( 3 Hz to 20 000 Hz ) on Right, Left, Center, Surround Right, Surround Left • optional channel LFE : woofer 3 to 120 Hz.