diff options
Diffstat (limited to 'trunk/codecs/g722/g722_decode.c')
-rw-r--r-- | trunk/codecs/g722/g722_decode.c | 398 |
1 files changed, 398 insertions, 0 deletions
diff --git a/trunk/codecs/g722/g722_decode.c b/trunk/codecs/g722/g722_decode.c new file mode 100644 index 000000000..1625acc86 --- /dev/null +++ b/trunk/codecs/g722/g722_decode.c @@ -0,0 +1,398 @@ +/* + * SpanDSP - a series of DSP components for telephony + * + * g722_decode.c - The ITU G.722 codec, decode part. + * + * 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 in part on a single channel G.722 codec which is: + * + * Copyright (c) CMU 1993 + * Computer Science, Speech Group + * Chengxiang Lu and Alex Hauptmann + * + * $Id$ + */ + +/*! \file */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <stdio.h> +#include <inttypes.h> +#include <memory.h> +#include <stdlib.h> +#if 0 +#include <tgmath.h> +#endif + +#include "g722.h" + +#if !defined(FALSE) +#define FALSE 0 +#endif +#if !defined(TRUE) +#define TRUE (!FALSE) +#endif + +static __inline__ int16_t saturate(int32_t amp) +{ + int16_t amp16; + + /* Hopefully this is optimised for the common case - not clipping */ + amp16 = (int16_t) amp; + if (amp == amp16) + return amp16; + if (amp > INT16_MAX) + return INT16_MAX; + return INT16_MIN; +} +/*- End of function --------------------------------------------------------*/ + +static void block4(g722_decode_state_t *s, int band, int d); + +static void block4(g722_decode_state_t *s, int band, int d) +{ + int wd1; + int wd2; + int wd3; + int i; + + /* Block 4, RECONS */ + s->band[band].d[0] = d; + s->band[band].r[0] = saturate(s->band[band].s + d); + + /* Block 4, PARREC */ + s->band[band].p[0] = saturate(s->band[band].sz + d); + + /* Block 4, UPPOL2 */ + for (i = 0; i < 3; i++) + s->band[band].sg[i] = s->band[band].p[i] >> 15; + wd1 = saturate(s->band[band].a[1] << 2); + + wd2 = (s->band[band].sg[0] == s->band[band].sg[1]) ? -wd1 : wd1; + if (wd2 > 32767) + wd2 = 32767; + wd3 = (s->band[band].sg[0] == s->band[band].sg[2]) ? 128 : -128; + wd3 += (wd2 >> 7); + wd3 += (s->band[band].a[2]*32512) >> 15; + if (wd3 > 12288) + wd3 = 12288; + else if (wd3 < -12288) + wd3 = -12288; + s->band[band].ap[2] = wd3; + + /* Block 4, UPPOL1 */ + s->band[band].sg[0] = s->band[band].p[0] >> 15; + s->band[band].sg[1] = s->band[band].p[1] >> 15; + wd1 = (s->band[band].sg[0] == s->band[band].sg[1]) ? 192 : -192; + wd2 = (s->band[band].a[1]*32640) >> 15; + + s->band[band].ap[1] = saturate(wd1 + wd2); + wd3 = saturate(15360 - s->band[band].ap[2]); + if (s->band[band].ap[1] > wd3) + s->band[band].ap[1] = wd3; + else if (s->band[band].ap[1] < -wd3) + s->band[band].ap[1] = -wd3; + + /* Block 4, UPZERO */ + wd1 = (d == 0) ? 0 : 128; + s->band[band].sg[0] = d >> 15; + for (i = 1; i < 7; i++) + { + s->band[band].sg[i] = s->band[band].d[i] >> 15; + wd2 = (s->band[band].sg[i] == s->band[band].sg[0]) ? wd1 : -wd1; + wd3 = (s->band[band].b[i]*32640) >> 15; + s->band[band].bp[i] = saturate(wd2 + wd3); + } + + /* Block 4, DELAYA */ + for (i = 6; i > 0; i--) + { + s->band[band].d[i] = s->band[band].d[i - 1]; + s->band[band].b[i] = s->band[band].bp[i]; + } + + for (i = 2; i > 0; i--) + { + s->band[band].r[i] = s->band[band].r[i - 1]; + s->band[band].p[i] = s->band[band].p[i - 1]; + s->band[band].a[i] = s->band[band].ap[i]; + } + + /* Block 4, FILTEP */ + wd1 = saturate(s->band[band].r[1] + s->band[band].r[1]); + wd1 = (s->band[band].a[1]*wd1) >> 15; + wd2 = saturate(s->band[band].r[2] + s->band[band].r[2]); + wd2 = (s->band[band].a[2]*wd2) >> 15; + s->band[band].sp = saturate(wd1 + wd2); + + /* Block 4, FILTEZ */ + s->band[band].sz = 0; + for (i = 6; i > 0; i--) + { + wd1 = saturate(s->band[band].d[i] + s->band[band].d[i]); + s->band[band].sz += (s->band[band].b[i]*wd1) >> 15; + } + s->band[band].sz = saturate(s->band[band].sz); + + /* Block 4, PREDIC */ + s->band[band].s = saturate(s->band[band].sp + s->band[band].sz); +} +/*- End of function --------------------------------------------------------*/ + +g722_decode_state_t *g722_decode_init(g722_decode_state_t *s, int rate, int options) +{ + if (s == NULL) + { + if ((s = (g722_decode_state_t *) malloc(sizeof(*s))) == NULL) + return NULL; + } + memset(s, 0, sizeof(*s)); + if (rate == 48000) + s->bits_per_sample = 6; + else if (rate == 56000) + s->bits_per_sample = 7; + else + s->bits_per_sample = 8; + if ((options & G722_SAMPLE_RATE_8000)) + s->eight_k = TRUE; + if ((options & G722_PACKED) && s->bits_per_sample != 8) + s->packed = TRUE; + else + s->packed = FALSE; + s->band[0].det = 32; + s->band[1].det = 8; + return s; +} +/*- End of function --------------------------------------------------------*/ + +int g722_decode_release(g722_decode_state_t *s) +{ + free(s); + return 0; +} +/*- End of function --------------------------------------------------------*/ + +int g722_decode(g722_decode_state_t *s, int16_t amp[], const uint8_t g722_data[], int len) +{ + static const int wl[8] = {-60, -30, 58, 172, 334, 538, 1198, 3042 }; + static const int rl42[16] = {0, 7, 6, 5, 4, 3, 2, 1, 7, 6, 5, 4, 3, 2, 1, 0 }; + static const int ilb[32] = + { + 2048, 2093, 2139, 2186, 2233, 2282, 2332, + 2383, 2435, 2489, 2543, 2599, 2656, 2714, + 2774, 2834, 2896, 2960, 3025, 3091, 3158, + 3228, 3298, 3371, 3444, 3520, 3597, 3676, + 3756, 3838, 3922, 4008 + }; + static const int wh[3] = {0, -214, 798}; + static const int rh2[4] = {2, 1, 2, 1}; + static const int qm2[4] = {-7408, -1616, 7408, 1616}; + static const int qm4[16] = + { + 0, -20456, -12896, -8968, + -6288, -4240, -2584, -1200, + 20456, 12896, 8968, 6288, + 4240, 2584, 1200, 0 + }; + static const int qm5[32] = + { + -280, -280, -23352, -17560, + -14120, -11664, -9752, -8184, + -6864, -5712, -4696, -3784, + -2960, -2208, -1520, -880, + 23352, 17560, 14120, 11664, + 9752, 8184, 6864, 5712, + 4696, 3784, 2960, 2208, + 1520, 880, 280, -280 + }; + static const int qm6[64] = + { + -136, -136, -136, -136, + -24808, -21904, -19008, -16704, + -14984, -13512, -12280, -11192, + -10232, -9360, -8576, -7856, + -7192, -6576, -6000, -5456, + -4944, -4464, -4008, -3576, + -3168, -2776, -2400, -2032, + -1688, -1360, -1040, -728, + 24808, 21904, 19008, 16704, + 14984, 13512, 12280, 11192, + 10232, 9360, 8576, 7856, + 7192, 6576, 6000, 5456, + 4944, 4464, 4008, 3576, + 3168, 2776, 2400, 2032, + 1688, 1360, 1040, 728, + 432, 136, -432, -136 + }; + static const int qmf_coeffs[12] = + { + 3, -11, 12, 32, -210, 951, 3876, -805, 362, -156, 53, -11, + }; + + int dlowt; + int rlow; + int ihigh; + int dhigh; + int rhigh; + int xout1; + int xout2; + int wd1; + int wd2; + int wd3; + int code; + int outlen; + int i; + int j; + + outlen = 0; + rhigh = 0; + for (j = 0; j < len; ) + { + if (s->packed) + { + /* Unpack the code bits */ + if (s->in_bits < s->bits_per_sample) + { + s->in_buffer |= (g722_data[j++] << s->in_bits); + s->in_bits += 8; + } + code = s->in_buffer & ((1 << s->bits_per_sample) - 1); + s->in_buffer >>= s->bits_per_sample; + s->in_bits -= s->bits_per_sample; + } + else + { + code = g722_data[j++]; + } + + switch (s->bits_per_sample) + { + default: + case 8: + wd1 = code & 0x3F; + ihigh = (code >> 6) & 0x03; + wd2 = qm6[wd1]; + wd1 >>= 2; + break; + case 7: + wd1 = code & 0x1F; + ihigh = (code >> 5) & 0x03; + wd2 = qm5[wd1]; + wd1 >>= 1; + break; + case 6: + wd1 = code & 0x0F; + ihigh = (code >> 4) & 0x03; + wd2 = qm4[wd1]; + break; + } + /* Block 5L, LOW BAND INVQBL */ + wd2 = (s->band[0].det*wd2) >> 15; + /* Block 5L, RECONS */ + rlow = s->band[0].s + wd2; + /* Block 6L, LIMIT */ + if (rlow > 16383) + rlow = 16383; + else if (rlow < -16384) + rlow = -16384; + + /* Block 2L, INVQAL */ + wd2 = qm4[wd1]; + dlowt = (s->band[0].det*wd2) >> 15; + + /* Block 3L, LOGSCL */ + wd2 = rl42[wd1]; + wd1 = (s->band[0].nb*127) >> 7; + wd1 += wl[wd2]; + if (wd1 < 0) + wd1 = 0; + else if (wd1 > 18432) + wd1 = 18432; + s->band[0].nb = wd1; + + /* Block 3L, SCALEL */ + wd1 = (s->band[0].nb >> 6) & 31; + wd2 = 8 - (s->band[0].nb >> 11); + wd3 = (wd2 < 0) ? (ilb[wd1] << -wd2) : (ilb[wd1] >> wd2); + s->band[0].det = wd3 << 2; + + block4(s, 0, dlowt); + + if (!s->eight_k) + { + /* Block 2H, INVQAH */ + wd2 = qm2[ihigh]; + dhigh = (s->band[1].det*wd2) >> 15; + /* Block 5H, RECONS */ + rhigh = dhigh + s->band[1].s; + /* Block 6H, LIMIT */ + if (rhigh > 16383) + rhigh = 16383; + else if (rhigh < -16384) + rhigh = -16384; + + /* Block 2H, INVQAH */ + wd2 = rh2[ihigh]; + wd1 = (s->band[1].nb*127) >> 7; + wd1 += wh[wd2]; + if (wd1 < 0) + wd1 = 0; + else if (wd1 > 22528) + wd1 = 22528; + s->band[1].nb = wd1; + + /* Block 3H, SCALEH */ + wd1 = (s->band[1].nb >> 6) & 31; + wd2 = 10 - (s->band[1].nb >> 11); + wd3 = (wd2 < 0) ? (ilb[wd1] << -wd2) : (ilb[wd1] >> wd2); + s->band[1].det = wd3 << 2; + + block4(s, 1, dhigh); + } + + if (s->itu_test_mode) + { + amp[outlen++] = (int16_t) (rlow << 1); + amp[outlen++] = (int16_t) (rhigh << 1); + } + else + { + if (s->eight_k) + { + amp[outlen++] = (int16_t) rlow; + } + else + { + /* Apply the receive QMF */ + for (i = 0; i < 22; i++) + s->x[i] = s->x[i + 2]; + s->x[22] = rlow + rhigh; + s->x[23] = rlow - rhigh; + + xout1 = 0; + xout2 = 0; + for (i = 0; i < 12; i++) + { + xout2 += s->x[2*i]*qmf_coeffs[i]; + xout1 += s->x[2*i + 1]*qmf_coeffs[11 - i]; + } + amp[outlen++] = (int16_t) (xout1 >> 12); + amp[outlen++] = (int16_t) (xout2 >> 12); + } + } + } + return outlen; +} +/*- End of function --------------------------------------------------------*/ +/*- End of file ------------------------------------------------------------*/ |