diff options
author | Matthew Fredrickson <creslin@digium.com> | 2006-12-21 00:08:21 +0000 |
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committer | Matthew Fredrickson <creslin@digium.com> | 2006-12-21 00:08:21 +0000 |
commit | ba716659248f262ac2b45d16db686117f18f72ec (patch) | |
tree | 6bbb62ef8c3e5cd9df043b37a3541e8cac4f81ed /codecs/g722/g722.h | |
parent | 1546495afc1aedc6b7ce149ed2e03aa48d9928f7 (diff) |
Add codec G.722 support.
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@48661 65c4cc65-6c06-0410-ace0-fbb531ad65f3
Diffstat (limited to 'codecs/g722/g722.h')
-rw-r--r-- | codecs/g722/g722.h | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/codecs/g722/g722.h b/codecs/g722/g722.h new file mode 100644 index 000000000..95a9da8d0 --- /dev/null +++ b/codecs/g722/g722.h @@ -0,0 +1,141 @@ +/* + * SpanDSP - a series of DSP components for telephony + * + * g722.h - The ITU G.722 codec. + * + * Written by Steve Underwood <steveu@coppice.org> + * + * Copyright (C) 2005 Steve Underwood + * + * Despite my general liking of the GPL, I place my own contributions + * to this code in the public domain for the benefit of all mankind - + * even the slimy ones who might try to proprietize my work and use it + * to my detriment. + * + * Based on a single channel G.722 codec which is: + * + ***** Copyright (c) CMU 1993 ***** + * Computer Science, Speech Group + * Chengxiang Lu and Alex Hauptmann + * + * $Id$ + */ + + +/*! \file */ + +#if !defined(_G722_H_) +#define _G722_H_ + +/*! \page g722_page G.722 encoding and decoding +\section g722_page_sec_1 What does it do? +The G.722 module is a bit exact implementation of the ITU G.722 specification for all three +specified bit rates - 64000bps, 56000bps and 48000bps. It passes the ITU tests. + +To allow fast and flexible interworking with narrow band telephony, the encoder and decoder +support an option for the linear audio to be an 8k samples/second stream. In this mode the +codec is considerably faster, and still fully compatible with wideband terminals using G.722. + +\section g722_page_sec_2 How does it work? +???. +*/ + +enum +{ + G722_SAMPLE_RATE_8000 = 0x0001, + G722_PACKED = 0x0002 +}; + +typedef struct +{ + /*! TRUE if the operating in the special ITU test mode, with the band split filters + disabled. */ + int itu_test_mode; + /*! TRUE if the G.722 data is packed */ + int packed; + /*! TRUE if encode from 8k samples/second */ + int eight_k; + /*! 6 for 48000kbps, 7 for 56000kbps, or 8 for 64000kbps. */ + int bits_per_sample; + + /*! Signal history for the QMF */ + int x[24]; + + struct + { + int s; + int sp; + int sz; + int r[3]; + int a[3]; + int ap[3]; + int p[3]; + int d[7]; + int b[7]; + int bp[7]; + int sg[7]; + int nb; + int det; + } band[2]; + + unsigned int in_buffer; + int in_bits; + unsigned int out_buffer; + int out_bits; +} g722_encode_state_t; + +typedef struct +{ + /*! TRUE if the operating in the special ITU test mode, with the band split filters + disabled. */ + int itu_test_mode; + /*! TRUE if the G.722 data is packed */ + int packed; + /*! TRUE if decode to 8k samples/second */ + int eight_k; + /*! 6 for 48000kbps, 7 for 56000kbps, or 8 for 64000kbps. */ + int bits_per_sample; + + /*! Signal history for the QMF */ + int x[24]; + + struct + { + int s; + int sp; + int sz; + int r[3]; + int a[3]; + int ap[3]; + int p[3]; + int d[7]; + int b[7]; + int bp[7]; + int sg[7]; + int nb; + int det; + } band[2]; + + unsigned int in_buffer; + int in_bits; + unsigned int out_buffer; + int out_bits; +} g722_decode_state_t; + +#ifdef __cplusplus +extern "C" { +#endif + +g722_encode_state_t *g722_encode_init(g722_encode_state_t *s, int rate, int options); +int g722_encode_release(g722_encode_state_t *s); +int g722_encode(g722_encode_state_t *s, uint8_t g722_data[], const int16_t amp[], int len); + +g722_decode_state_t *g722_decode_init(g722_decode_state_t *s, int rate, int options); +int g722_decode_release(g722_decode_state_t *s); +int g722_decode(g722_decode_state_t *s, int16_t amp[], const uint8_t g722_data[], int len); + +#ifdef __cplusplus +} +#endif + +#endif |