A collection of freeware open-source audio codecs is a part of VC Freeware components.
The following audio codecs are implmentated in native Delphi source code and are ready to use.
Most of them are based on original C/C++ soucre codec from different sources.
||Logarithmic, 8 kHz, 64 kbit/s, CBR codec used mostly in telephony since 1972. Has two slightly different versions: μ-law (North America and Japan) and A-law (most other countries).
||Transform-based codec, 16 kHz, 24/48 kbit/s, CBR codec providing high quality with moderate bitrate optimized for both speech and music.
||RPE-LTP speech codec, 8 kHz, 13 kbit/s, moderate quality, low bitrate and complexity. WAV49 modification by Microsoft ACM implementation has a different bit order and is also supported.
||ETSI EN 300 961,
||ADPCM codec, 8 kHz, 32 kbit/s, low quality, very low complexity.
||IMA ADPCM specification
Download all codec sources as a part of VC Freeware components.