diff options
Diffstat (limited to 'src/audio/gsm/README')
| -rw-r--r-- | src/audio/gsm/README | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/src/audio/gsm/README b/src/audio/gsm/README new file mode 100644 index 0000000..cb6af85 --- /dev/null +++ b/src/audio/gsm/README @@ -0,0 +1,37 @@ + +GSM 06.10 13 kbit/s RPE/LTP speech compression available +-------------------------------------------------------- + +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. |