phd@speech1.cs.cmu.edu (Paul Dietz) (07/22/88)
In article <744@io.ATT.COM> tmk@io.UUCP (59481[rjb]-t.m.ko) writes: >There is a speech recognition chip SP1000 from General Instrument (?). >It uses linear predictive coding and does both recognition and systhesis. Could you tell us more about this chip? Sounds mighty interesting... --- phd
tmk@io.ATT.COM (59481[rjb]-t.m.ko) (07/25/88)
In article <2352@pt.cs.cmu.edu> phd@speech1.cs.cmu.edu (Paul Dietz) writes: >In article <744@io.ATT.COM> tmk@io.UUCP (59481[rjb]-t.m.ko) writes: >>There is a speech recognition chip SP1000 from General Instrument (?). >>It uses linear predictive coding and does both recognition and systhesis. > >Could you tell us more about this chip? Sounds mighty interesting... > >--- phd For more detail, c.f. the article: "Ciarcia's Circuit Cellar: The Lis'ner 1000" by Steve Ciarcia in Byte, Nov., 1984. The following is a description quoted from this article: "The SP1000 is a 5-volt 28-pin NMOS microprocessor peripheral chip that can be used for both speech recognition and LPC speech synthesis. Using a bidirectional data bus and control lines, the SP1000 interfaces to most 8-bit processors as a memory mapped peripheral device. The unique aspect of the SP1000 is its ability to do LPC analysis in real time........" ****************************************************************************** Tsz-Mei Ko ARPA: bentley!tmk@att.ARPA AT&T Bell Labs UUCP: tmk@bentley.UUCP LC 3S-D20 184 Liberty Corner Road {att-ih,decwrl,amdahl,linus}!ihnp4!bentley!tmk Warren, NJ 07060-0908 *******************************************************************************
firat@alberta.UUCP (Firat Uludamar) (07/26/88)
In article <2352@pt.cs.cmu.edu> phd@speech1.cs.cmu.edu (Paul Dietz) writes: >In article <744@io.ATT.COM> tmk@io.UUCP (59481[rjb]-t.m.ko) writes: >>There is a speech recognition chip SP1000 from General Instrument (?). >>It uses linear predictive coding and does both recognition and systhesis. > >Could you tell us more about this chip? Sounds mighty interesting... > >--- phd SP1000 is a 5V 28-pin chip which can be configured for both speech recognition and synthesis. It can be used as a memory-mapped I/O device. It has to be used with analog signal conditioning circuitry (lowpass and preemphasis filter, variable gain amplifier, anti-aliasing filter, A/D converter for recognition). Recognition mode: Sampling frequency [5.0, 15.9 kHz] can be controlled by sw. It has got a 8-stage all-zero lattice filter to do Linear Predictive Coding (LPC) analysis. LPC analysis can be performed on frames of digitized speech samples. The number of samples in a frame can be specified by sw. The result of LPC analysis is 8 reflection coefficients (8-bit each) which can be retrieved from the SP1000. Reflection coeffs have to do with lossless acoustic tube model for speech. "Linear Prediction of Speech" by Markel and Gray (Springer- Verlag 1976) is an excellent reference on speech models etc. Also, the SP1000 computes the avg magnitude of samples in an analysis frame. Synthesis mode: Sampling frequency is sw controlled in the range of [4.0, 12.7 kHz]. The SP1000 uses a ten-stage, all-pole lattice filter for synthesis. Each stage requires 9-bit reflection coeff which can be written to the chip using 8-bit bidirectional address bus and two different write commands. 8 different excitation sequences (2 constant, pseudo-random seq for unvoiced speech, voiced excitation, male, female, falsetto, and creaky) can be chosen through sw. The output is pulse-width modulated signal which is run through a low-pass filter and a speaker. More info on SP1000 can be obtained from General Instruments branch in Chandler, Arizona. As for the references on speech chip technology, "Electronic Speech Synthesis Techniques, Technology, and Applications" by Geoff Bristow (ed.) and "Computer Speech Processing" by Fallside and Woods contain few interesting chapters. Also see Montlick et al.'s paper in IEEE ASSP 1983 Conf (pp. 499-501). Firat Uludamar