/* $Id$ */ /* * Copyright (C) 2003-2006 Benny Prijono * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ /* This file contains file from Sun Microsystems, Inc, with the complete * notice in the second half of this file. */ #include #include #include #include #include #define G711_BPS 64000 #define G711_CODEC_CNT 0 /* number of codec to preallocate in memory */ /* These are the only public functions exported to applications */ PJ_DECL(pj_status_t) g711_init_factory (pjmedia_codec_factory *factory, pj_pool_t *pool); PJ_DECL(pj_status_t) g711_deinit_factory (pjmedia_codec_factory *factory); /* Algorithm prototypes. */ static unsigned char linear2alaw(int pcm_val); /* 2's complement (16-bit range) */ static int alaw2linear(unsigned char a_val); static unsigned char linear2ulaw(int pcm_val); static int ulaw2linear(unsigned char u_val); /* Prototypes for G711 factory */ static pj_status_t g711_match_id( pjmedia_codec_factory *factory, const pjmedia_codec_info *id ); static pj_status_t g711_default_attr( pjmedia_codec_factory *factory, const pjmedia_codec_info *id, pjmedia_codec_param *attr ); static pj_status_t g711_enum_codecs (pjmedia_codec_factory *factory, unsigned *count, pjmedia_codec_info codecs[]); static pj_status_t g711_alloc_codec( pjmedia_codec_factory *factory, const pjmedia_codec_info *id, pjmedia_codec **p_codec); static pj_status_t g711_dealloc_codec( pjmedia_codec_factory *factory, pjmedia_codec *codec ); /* Prototypes for G711 implementation. */ static pj_status_t g711_codec_default_attr (pjmedia_codec *codec, pjmedia_codec_param *attr); static pj_status_t g711_init( pjmedia_codec *codec, pj_pool_t *pool ); static pj_status_t g711_open( pjmedia_codec *codec, pjmedia_codec_param *attr ); static pj_status_t g711_close( pjmedia_codec *codec ); static pj_status_t g711_encode( pjmedia_codec *codec, const struct pjmedia_frame *input, unsigned output_buf_len, struct pjmedia_frame *output); static pj_status_t g711_decode( pjmedia_codec *codec, const struct pjmedia_frame *input, unsigned output_buf_len, struct pjmedia_frame *output); /* Definition for G711 codec operations. */ static pjmedia_codec_op g711_op = { &g711_codec_default_attr , &g711_init, &g711_open, &g711_close, &g711_encode, &g711_decode }; /* Definition for G711 codec factory operations. */ static pjmedia_codec_factory_op g711_factory_op = { &g711_match_id, &g711_default_attr, &g711_enum_codecs, &g711_alloc_codec, &g711_dealloc_codec }; /* G711 factory private data */ struct g711_factory_private { pj_pool_t *pool; pjmedia_codec codec_list; }; /* G711 codec private data. */ struct g711_private { unsigned pt; }; PJ_DEF(pj_status_t) g711_init_factory (pjmedia_codec_factory *factory, pj_pool_t *pool) { struct g711_factory_private *priv; //enum { CODEC_MEM_SIZE = sizeof(pjmedia_codec) + sizeof(struct g711_private) + 4 }; /* Create pool. */ /* pool = pj_pool_pool_create_pool(pp, "g711ftry", G711_CODEC_CNT*CODEC_MEM_SIZE + sizeof(struct g711_factory_private), CODEC_MEM_SIZE, NULL); if (!pool) return -1; */ priv = pj_pool_alloc(pool, sizeof(struct g711_factory_private)); if (!priv) return -1; factory->factory_data = priv; factory->op = &g711_factory_op; priv->pool = pool; pj_list_init(&priv->codec_list); return 0; } PJ_DEF(pj_status_t) g711_deinit_factory (pjmedia_codec_factory *factory) { struct g711_factory_private *priv = factory->factory_data; /* Invalidate member to help detect errors */ priv->pool = NULL; priv->codec_list.next = priv->codec_list.prev = NULL; return 0; } static pj_status_t g711_match_id( pjmedia_codec_factory *factory, const pjmedia_codec_info *id ) { PJ_UNUSED_ARG(factory); /* It's sufficient to check payload type only. */ return (id->pt==PJMEDIA_RTP_PT_PCMU || id->pt==PJMEDIA_RTP_PT_PCMA) ? 0 : -1; } static pj_status_t g711_default_attr (pjmedia_codec_factory *factory, const pjmedia_codec_info *id, pjmedia_codec_param *attr ) { PJ_UNUSED_ARG(factory); memset(attr, 0, sizeof(pjmedia_codec_param)); attr->sample_rate = 8000; attr->avg_bps = G711_BPS; attr->pcm_bits_per_sample = 16; attr->ptime = 20; attr->pt = id->pt; /* Default all flag bits disabled. */ return PJ_SUCCESS; } static pj_status_t g711_enum_codecs(pjmedia_codec_factory *factory, unsigned *count, pjmedia_codec_info codecs[]) { PJ_UNUSED_ARG(factory); if (*count > 0) { codecs[0].type = PJMEDIA_TYPE_AUDIO; codecs[0].pt = PJMEDIA_RTP_PT_PCMU; codecs[0].encoding_name = pj_str("PCMU"); codecs[0].sample_rate = 8000; } if (*count > 1) { codecs[1].type = PJMEDIA_TYPE_AUDIO; codecs[1].pt = PJMEDIA_RTP_PT_PCMA; codecs[1].encoding_name = pj_str("PCMA"); codecs[1].sample_rate = 8000; } if (*count > 0) *count=1; if (*count > 1) *count=2; return PJ_SUCCESS; } static pj_status_t g711_alloc_codec( pjmedia_codec_factory *factory, const pjmedia_codec_info *id, pjmedia_codec **p_codec) { struct g711_factory_private *priv = factory->factory_data; pjmedia_codec *codec = NULL; /* Allocate new codec if no more is available */ if (pj_list_empty(&priv->codec_list)) { struct g711_private *codec_priv; codec = pj_pool_alloc(priv->pool, sizeof(pjmedia_codec)); codec_priv = pj_pool_alloc(priv->pool, sizeof(struct g711_private)); if (!codec || !codec_priv) return PJ_ENOMEM; codec_priv->pt = id->pt; codec->factory = factory; codec->op = &g711_op; codec->codec_data = codec_priv; } else { codec = priv->codec_list.next; pj_list_erase(codec); } /* Zero the list, for error detection in g711_dealloc_codec */ codec->next = codec->prev = NULL; *p_codec = codec; return PJ_SUCCESS; } static pj_status_t g711_dealloc_codec( pjmedia_codec_factory *factory, pjmedia_codec *codec ) { struct g711_factory_private *priv = factory->factory_data; /* Check that this node has not been deallocated before */ pj_assert (codec->next==NULL && codec->prev==NULL); if (codec->next!=NULL || codec->prev!=NULL) { return PJ_EINVALIDOP; } /* Insert at the back of the list */ pj_list_insert_before(&priv->codec_list, codec); return PJ_SUCCESS; } static pj_status_t g711_codec_default_attr (pjmedia_codec *codec, pjmedia_codec_param *attr) { struct g711_private *priv = codec->codec_data; pjmedia_codec_info id; id.pt = priv->pt; return g711_default_attr (NULL, &id, attr); } static pj_status_t g711_init( pjmedia_codec *codec, pj_pool_t *pool ) { /* There's nothing to do here really */ PJ_UNUSED_ARG(codec); PJ_UNUSED_ARG(pool); return PJ_SUCCESS; } static pj_status_t g711_open( pjmedia_codec *codec, pjmedia_codec_param *attr ) { struct g711_private *priv = codec->codec_data; priv->pt = attr->pt; return PJ_SUCCESS; } static pj_status_t g711_close( pjmedia_codec *codec ) { PJ_UNUSED_ARG(codec); /* Nothing to do */ return PJ_SUCCESS; } static pj_status_t g711_encode( pjmedia_codec *codec, const struct pjmedia_frame *input, unsigned output_buf_len, struct pjmedia_frame *output) { pj_int16_t *samples = (pj_int16_t*) input->buf; struct g711_private *priv = codec->codec_data; /* Check output buffer length */ if (output_buf_len < input->size / 2) return -1; /* Encode */ if (priv->pt == PJMEDIA_RTP_PT_PCMA) { unsigned i; pj_uint8_t *dst = output->buf; for (i=0; i!=input->size/2; ++i, ++dst) { *dst = linear2alaw(samples[i]); } } else if (priv->pt == PJMEDIA_RTP_PT_PCMU) { unsigned i; pj_uint8_t *dst = output->buf; for (i=0; i!=input->size/2; ++i, ++dst) { *dst = linear2ulaw(samples[i]); } } else { return -1; } output->type = PJMEDIA_FRAME_TYPE_AUDIO; output->size = input->size / 2; return 0; } static pj_status_t g711_decode( pjmedia_codec *codec, const struct pjmedia_frame *input, unsigned output_buf_len, struct pjmedia_frame *output) { struct g711_private *priv = codec->codec_data; /* Check output buffer length */ if (output_buf_len < input->size * 2) return -1; /* Decode */ if (priv->pt == PJMEDIA_RTP_PT_PCMA) { unsigned i; pj_uint8_t *src = input->buf; pj_uint16_t *dst = output->buf; for (i=0; i!=input->size; ++i) { *dst++ = (pj_uint16_t) alaw2linear(*src++); } } else if (priv->pt == PJMEDIA_RTP_PT_PCMU) { unsigned i; pj_uint8_t *src = input->buf; pj_uint16_t *dst = output->buf; for (i=0; i!=input->size; ++i) { *dst++ = (pj_uint16_t) ulaw2linear(*src++); } } else { return -1; } output->type = PJMEDIA_FRAME_TYPE_AUDIO; output->size = input->size * 2; return 0; } /* * This source code is a product of Sun Microsystems, Inc. and is provided * for unrestricted use. Users may copy or modify this source code without * charge. * * SUN SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING * THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE. * * Sun source code is provided with no support and without any obligation on * the part of Sun Microsystems, Inc. to assist in its use, correction, * modification or enhancement. * * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE * OR ANY PART THEREOF. * * In no event will Sun Microsystems, Inc. be liable for any lost revenue * or profits or other special, indirect and consequential damages, even if * Sun has been advised of the possibility of such damages. * * Sun Microsystems, Inc. * 2550 Garcia Avenue * Mountain View, California 94043 */ #ifdef _MSC_VER # pragma warning ( disable: 4244 ) /* Conversion from int to char etc */ #endif /* * g711.c * * u-law, A-law and linear PCM conversions. */ #define SIGN_BIT (0x80) /* Sign bit for a A-law byte. */ #define QUANT_MASK (0xf) /* Quantization field mask. */ #define NSEGS (8) /* Number of A-law segments. */ #define SEG_SHIFT (4) /* Left shift for segment number. */ #define SEG_MASK (0x70) /* Segment field mask. */ static short seg_end[8] = {0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF}; /* copy from CCITT G.711 specifications */ static unsigned char _u2a[128] = { /* u- to A-law conversions */ 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 27, 29, 31, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 46, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128}; static unsigned char _a2u[128] = { /* A- to u-law conversions */ 1, 3, 5, 7, 9, 11, 13, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 32, 33, 33, 34, 34, 35, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 48, 49, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127}; static int search( int val, short *table, int size) { int i; for (i = 0; i < size; i++) { if (val <= *table++) return (i); } return (size); } /* * linear2alaw() - Convert a 16-bit linear PCM value to 8-bit A-law * * linear2alaw() accepts an 16-bit integer and encodes it as A-law data. * * Linear Input Code Compressed Code * ------------------------ --------------- * 0000000wxyza 000wxyz * 0000001wxyza 001wxyz * 000001wxyzab 010wxyz * 00001wxyzabc 011wxyz * 0001wxyzabcd 100wxyz * 001wxyzabcde 101wxyz * 01wxyzabcdef 110wxyz * 1wxyzabcdefg 111wxyz * * For further information see John C. Bellamy's Digital Telephony, 1982, * John Wiley & Sons, pps 98-111 and 472-476. */ static unsigned char linear2alaw( int pcm_val) /* 2's complement (16-bit range) */ { int mask; int seg; unsigned char aval; if (pcm_val >= 0) { mask = 0xD5; /* sign (7th) bit = 1 */ } else { mask = 0x55; /* sign bit = 0 */ pcm_val = -pcm_val - 8; } /* Convert the scaled magnitude to segment number. */ seg = search(pcm_val, seg_end, 8); /* Combine the sign, segment, and quantization bits. */ if (seg >= 8) /* out of range, return maximum value. */ return (0x7F ^ mask); else { aval = seg << SEG_SHIFT; if (seg < 2) aval |= (pcm_val >> 4) & QUANT_MASK; else aval |= (pcm_val >> (seg + 3)) & QUANT_MASK; return (aval ^ mask); } } /* * alaw2linear() - Convert an A-law value to 16-bit linear PCM * */ static int alaw2linear( unsigned char a_val) { int t; int seg; a_val ^= 0x55; t = (a_val & QUANT_MASK) << 4; seg = ((unsigned)a_val & SEG_MASK) >> SEG_SHIFT; switch (seg) { case 0: t += 8; break; case 1: t += 0x108; break; default: t += 0x108; t <<= seg - 1; } return ((a_val & SIGN_BIT) ? t : -t); } #define BIAS (0x84) /* Bias for linear code. */ /* * linear2ulaw() - Convert a linear PCM value to u-law * * In order to simplify the encoding process, the original linear magnitude * is biased by adding 33 which shifts the encoding range from (0 - 8158) to * (33 - 8191). The result can be seen in the following encoding table: * * Biased Linear Input Code Compressed Code * ------------------------ --------------- * 00000001wxyza 000wxyz * 0000001wxyzab 001wxyz * 000001wxyzabc 010wxyz * 00001wxyzabcd 011wxyz * 0001wxyzabcde 100wxyz * 001wxyzabcdef 101wxyz * 01wxyzabcdefg 110wxyz * 1wxyzabcdefgh 111wxyz * * Each biased linear code has a leading 1 which identifies the segment * number. The value of the segment number is equal to 7 minus the number * of leading 0's. The quantization interval is directly available as the * four bits wxyz. * The trailing bits (a - h) are ignored. * * Ordinarily the complement of the resulting code word is used for * transmission, and so the code word is complemented before it is returned. * * For further information see John C. Bellamy's Digital Telephony, 1982, * John Wiley & Sons, pps 98-111 and 472-476. */ static unsigned char linear2ulaw( int pcm_val) /* 2's complement (16-bit range) */ { int mask; int seg; unsigned char uval; /* Get the sign and the magnitude of the value. */ if (pcm_val < 0) { pcm_val = BIAS - pcm_val; mask = 0x7F; } else { pcm_val += BIAS; mask = 0xFF; } /* Convert the scaled magnitude to segment number. */ seg = search(pcm_val, seg_end, 8); /* * Combine the sign, segment, quantization bits; * and complement the code word. */ if (seg >= 8) /* out of range, return maximum value. */ return (0x7F ^ mask); else { uval = (seg << 4) | ((pcm_val >> (seg + 3)) & 0xF); return (uval ^ mask); } } /* * ulaw2linear() - Convert a u-law value to 16-bit linear PCM * * First, a biased linear code is derived from the code word. An unbiased * output can then be obtained by subtracting 33 from the biased code. * * Note that this function expects to be passed the complement of the * original code word. This is in keeping with ISDN conventions. */ static int ulaw2linear( unsigned char u_val) { int t; /* Complement to obtain normal u-law value. */ u_val = ~u_val; /* * Extract and bias the quantization bits. Then * shift up by the segment number and subtract out the bias. */ t = ((u_val & QUANT_MASK) << 3) + BIAS; t <<= ((unsigned)u_val & SEG_MASK) >> SEG_SHIFT; return ((u_val & SIGN_BIT) ? (BIAS - t) : (t - BIAS)); } /* A-law to u-law conversion */ unsigned char alaw2ulaw( unsigned char aval) { aval &= 0xff; return ((aval & 0x80) ? (0xFF ^ _a2u[aval ^ 0xD5]) : (0x7F ^ _a2u[aval ^ 0x55])); } /* u-law to A-law conversion */ unsigned char ulaw2alaw( unsigned char uval) { uval &= 0xff; return ((uval & 0x80) ? (0xD5 ^ (_u2a[0xFF ^ uval] - 1)) : (0x55 ^ (_u2a[0x7F ^ uval] - 1))); }