speech audio processing coding enhancement audio library adpcm acelp pulse density

speech Audio codecs adpcm acelp  Audio codecs

Vocoders, Audio Codecs and Speech Compression Software
GAO Research
http://www.gaoresearch.com › products
ITU-T Vocoder Standards for Speech Processing Software and Audio Processing Codecs ; ITU-T G.723.1, 6.3 and 5.3 kbit/s, MP-MLQ, and ACELP based codec ; ITU-T G.

Comparison of audio coding formats - Wikipedia
https://en.wikipedia.org/wiki/Comparison_of_audio_coding_formats

TwoCC - MultimediaWiki
https://wiki.multimedia.cx/index.php/TwoCC
The TwoCC is the audio counterpart to the video FourCC. It is the audio format identifier used in the RIFF based multimedia formats by Microsoft (WAV and AVI). The TwoCC is 2 bytes long and stored in little endian format on disk. You can register your TwoCC with Microsoft but it seems that only some companies perform this process.
https://wiki.multimedia.cx/index.php/Category:Audio_Codecs

G.7xx: Audio (Voice) Compression Protocols (CODEC) (PDF)
Transcoding of Voice Codecs G.711 to G.729 and ... 
PDF iTu T G.7xx Standards for Speech Codec

https://academic-accelerator.com/encyclopedia/zh/g-722
g.722 G 722: 最新的百科全書、新聞、評論和研究

https://www.wikiwand.com/en/List_of_video_compression_formats
List of codecs - Wikiwand

Non-compression    Linear pulse-code modulation (LPCM, generally only described as PCM) is the format for uncompressed audio in media files and it is also the standard for CD-DA; note that in computers, LPCM is usually stored in container formats such as WAV, AIFF, or AU, or as raw audio format, although not technically necessary.        FFmpeg    Pulse-density modulation (PDM)        Direct Stream Digital (DSD) is standard for Super Audio CD            foobar2000 Super Audio CD Decoder (based on MPEG-4 DST reference decoder)            FFmpeg (based on dsd2pcm)    Pulse-amplitude modulation (PAM)