VQF, TwinVQ (transform-domain weighted interleaved vector quantization), is an audio compression technique developed by Nippon Telegraph and Telephone Corporation (NTT). The compression technique has been used in both standardized and proprietary designs.
A proprietary audio compression format called TwinVQ was developed by Nippon Telegraph and Telephone Corporation (NTT) and marketed by Yamaha under the name SoundVQ. Its file extension is .vqf.
TwinVQ uses Twin vector quantization. The proprietary TwinVQ codec supports constant bit rate encoding at 80, 96, 112, 128, 160 and 192 kbit/s. It was claimed that TwinVQ files are about 30 to 35% smaller than MP3 files of adequate quality. For example, a 96 kbit/s TwinVQ file allegedly has roughly the same quality as a 128 kbit/s MP3 file. The higher quality is achieved at the cost of higher processor usage.
Yamaha marketed TwinVQ as an alternative to MP3, but the format never became very popular. This could be attributed to the proprietary nature of the format -- third party software was scarce and there was no hardware support. Also the encoding was extremely slow and there was not much music available in TwinVQ format. As other MP3 alternatives emerged, TwinVQ quickly became obsolete.
You can use mpcstar to open files with this suffix. http://www.mpcstar.com/
