QDesign
Encyclopedia
QDesign is a music codec
, originally known as LBpack, by Dmitry Shmunk. QDesign corporation bought the codec and hired the developer to create what would become the official audio compression in Apple Computer
's QuickTime
v3.
The codec's official name is "RaveSound", but is commonly called QDesign Codec. It is optimized to compress quite well at very low bitrates, but its aggressiveness introduces audible artifacts at higher bitrates.
The personal version comes with QuickTime Pro and allows encoding at bitrates up to 48 kbit/s. The professional version allows bitrates up to 128 kbit/s.
Apple is now steering away from proprietary codecs in QuickTime like Sorenson Video and QDesign, and focusing on standards (MPEG-4
). In recent years, usage of QDMC has generally been eschewed in favor of AAC
.
Codec
A codec is a device or computer program capable of encoding or decoding a digital data stream or signal. The word codec is a portmanteau of "compressor-decompressor" or, more commonly, "coder-decoder"...
, originally known as LBpack, by Dmitry Shmunk. QDesign corporation bought the codec and hired the developer to create what would become the official audio compression in Apple Computer
Apple Computer
Apple Inc. is an American multinational corporation that designs and markets consumer electronics, computer software, and personal computers. The company's best-known hardware products include the Macintosh line of computers, the iPod, the iPhone and the iPad...
's QuickTime
QuickTime
QuickTime is an extensible proprietary multimedia framework developed by Apple Inc., capable of handling various formats of digital video, picture, sound, panoramic images, and interactivity. The classic version of QuickTime is available for Windows XP and later, as well as Mac OS X Leopard and...
v3.
The codec's official name is "RaveSound", but is commonly called QDesign Codec. It is optimized to compress quite well at very low bitrates, but its aggressiveness introduces audible artifacts at higher bitrates.
The personal version comes with QuickTime Pro and allows encoding at bitrates up to 48 kbit/s. The professional version allows bitrates up to 128 kbit/s.
Apple is now steering away from proprietary codecs in QuickTime like Sorenson Video and QDesign, and focusing on standards (MPEG-4
MPEG-4
MPEG-4 is a method of defining compression of audio and visual digital data. It was introduced in late 1998 and designated a standard for a group of audio and video coding formats and related technology agreed upon by the ISO/IEC Moving Picture Experts Group under the formal standard ISO/IEC...
). In recent years, usage of QDMC has generally been eschewed in favor of AAC
Advanced Audio Coding
Advanced Audio Coding is a standardized, lossy compression and encoding scheme for digital audio. Designed to be the successor of the MP3 format, AAC generally achieves better sound quality than MP3 at similar bit rates....
.
External links
- QDMC's site at QDesign
- QDesign encoders are available at ReallyRareWares.