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- GSM 06.10 13 kbit/s RPE/LTP speech compression available
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- The Communications and Operating Systems Research Group (KBS) at the
- Technische Universitaet Berlin is currently working on a set of
- UNIX-based tools for computer-mediated telecooperation that will be
- made freely available.
- As part of this effort we are publishing an implementation of the
- European GSM 06.10 provisional standard for full-rate speech
- transcoding, prI-ETS 300 036, which uses RPE/LTP (residual pulse
- excitation/long term prediction) coding at 13 kbit/s.
- GSM 06.10 compresses frames of 160 13-bit samples (8 kHz sampling
- rate, i.e. a frame rate of 50 Hz) into 260 bits; for compatibility
- with typical UNIX applications, our implementation turns frames of 160
- 16-bit linear samples into 33-byte frames (1650 Bytes/s).
- The quality of the algorithm is good enough for reliable speaker
- recognition; even music often survives transcoding in recognizable
- form (given the bandwidth limitations of 8 kHz sampling rate).
- The interfaces offered are a front end modelled after compress(1), and
- a library API. Compression and decompression run faster than realtime
- on most SPARCstations. The implementation has been verified against the
- ETSI standard test patterns.
- Jutta Degener (jutta@cs.tu-berlin.de)
- Carsten Bormann (cabo@cs.tu-berlin.de)
- Communications and Operating Systems Research Group, TU Berlin
- Fax: +49.30.31425156, Phone: +49.30.31424315
- --
- Copyright 1992 by Jutta Degener and Carsten Bormann, Technische
- Universitaet Berlin. See the accompanying file "COPYRIGHT" for
- details. THERE IS ABSOLUTELY NO WARRANTY FOR THIS SOFTWARE.
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