From 165cc6fb9defcd79fd71c08167f3e8df26b058ff Mon Sep 17 00:00:00 2001 From: Vittorio Giovara Date: Mon, 23 Nov 2015 17:10:53 -0500 Subject: g723_1: Move sharable functions to a separate file Signed-off-by: Vittorio Giovara --- libavcodec/g723_1.c | 267 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 267 insertions(+) create mode 100644 libavcodec/g723_1.c (limited to 'libavcodec/g723_1.c') diff --git a/libavcodec/g723_1.c b/libavcodec/g723_1.c new file mode 100644 index 0000000000..af4777cc35 --- /dev/null +++ b/libavcodec/g723_1.c @@ -0,0 +1,267 @@ +/* + * G.723.1 compatible decoder + * Copyright (c) 2006 Benjamin Larsson + * Copyright (c) 2010 Mohamed Naufal Basheer + * + * This file is part of Libav. + * + * Libav is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * Libav 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with Libav; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include + +#include "libavutil/common.h" + +#include "acelp_vectors.h" +#include "avcodec.h" +#include "celp_math.h" +#include "g723_1.h" + +int ff_g723_1_scale_vector(int16_t *dst, const int16_t *vector, int length) +{ + int bits, max = 0; + int i; + + for (i = 0; i < length; i++) + max |= FFABS(vector[i]); + + max = FFMIN(max, 0x7FFF); + bits = ff_g723_1_normalize_bits(max, 15); + + for (i = 0; i < length; i++) + dst[i] = vector[i] << bits >> 3; + + return bits - 3; +} + +int ff_g723_1_normalize_bits(int num, int width) +{ + return width - av_log2(num) - 1; +} + +int ff_g723_1_dot_product(const int16_t *a, const int16_t *b, int length) +{ + int i, sum = 0; + + for (i = 0; i < length; i++) { + int prod = a[i] * b[i]; + sum = av_sat_dadd32(sum, prod); + } + return sum; +} + +void ff_g723_1_get_residual(int16_t *residual, int16_t *prev_excitation, + int lag) +{ + int offset = PITCH_MAX - PITCH_ORDER / 2 - lag; + int i; + + residual[0] = prev_excitation[offset]; + residual[1] = prev_excitation[offset + 1]; + + offset += 2; + for (i = 2; i < SUBFRAME_LEN + PITCH_ORDER - 1; i++) + residual[i] = prev_excitation[offset + (i - 2) % lag]; +} + +void ff_g723_1_gen_dirac_train(int16_t *buf, int pitch_lag) +{ + int16_t vector[SUBFRAME_LEN]; + int i, j; + + memcpy(vector, buf, SUBFRAME_LEN * sizeof(*vector)); + for (i = pitch_lag; i < SUBFRAME_LEN; i += pitch_lag) { + for (j = 0; j < SUBFRAME_LEN - i; j++) + buf[i + j] += vector[j]; + } +} + +void ff_g723_1_gen_acb_excitation(int16_t *vector, int16_t *prev_excitation, + int pitch_lag, G723_1_Subframe *subfrm, + enum Rate cur_rate) +{ + int16_t residual[SUBFRAME_LEN + PITCH_ORDER - 1]; + const int16_t *cb_ptr; + int lag = pitch_lag + subfrm->ad_cb_lag - 1; + + int i; + int sum; + + ff_g723_1_get_residual(residual, prev_excitation, lag); + + /* Select quantization table */ + if (cur_rate == RATE_6300 && pitch_lag < SUBFRAME_LEN - 2) + cb_ptr = adaptive_cb_gain85; + else + cb_ptr = adaptive_cb_gain170; + + /* Calculate adaptive vector */ + cb_ptr += subfrm->ad_cb_gain * 20; + for (i = 0; i < SUBFRAME_LEN; i++) { + sum = ff_g723_1_dot_product(residual + i, cb_ptr, PITCH_ORDER); + vector[i] = av_sat_dadd32(1 << 15, sum) >> 16; + } +} + +/** + * Convert LSP frequencies to LPC coefficients. + * + * @param lpc buffer for LPC coefficients + */ +static void lsp2lpc(int16_t *lpc) +{ + int f1[LPC_ORDER / 2 + 1]; + int f2[LPC_ORDER / 2 + 1]; + int i, j; + + /* Calculate negative cosine */ + for (j = 0; j < LPC_ORDER; j++) { + int index = (lpc[j] >> 7) & 0x1FF; + int offset = lpc[j] & 0x7f; + int temp1 = cos_tab[index] << 16; + int temp2 = (cos_tab[index + 1] - cos_tab[index]) * + ((offset << 8) + 0x80) << 1; + + lpc[j] = -(av_sat_dadd32(1 << 15, temp1 + temp2) >> 16); + } + + /* + * Compute sum and difference polynomial coefficients + * (bitexact alternative to lsp2poly() in lsp.c) + */ + /* Initialize with values in Q28 */ + f1[0] = 1 << 28; + f1[1] = (lpc[0] << 14) + (lpc[2] << 14); + f1[2] = lpc[0] * lpc[2] + (2 << 28); + + f2[0] = 1 << 28; + f2[1] = (lpc[1] << 14) + (lpc[3] << 14); + f2[2] = lpc[1] * lpc[3] + (2 << 28); + + /* + * Calculate and scale the coefficients by 1/2 in + * each iteration for a final scaling factor of Q25 + */ + for (i = 2; i < LPC_ORDER / 2; i++) { + f1[i + 1] = f1[i - 1] + MULL2(f1[i], lpc[2 * i]); + f2[i + 1] = f2[i - 1] + MULL2(f2[i], lpc[2 * i + 1]); + + for (j = i; j >= 2; j--) { + f1[j] = MULL2(f1[j - 1], lpc[2 * i]) + + (f1[j] >> 1) + (f1[j - 2] >> 1); + f2[j] = MULL2(f2[j - 1], lpc[2 * i + 1]) + + (f2[j] >> 1) + (f2[j - 2] >> 1); + } + + f1[0] >>= 1; + f2[0] >>= 1; + f1[1] = ((lpc[2 * i] << 16 >> i) + f1[1]) >> 1; + f2[1] = ((lpc[2 * i + 1] << 16 >> i) + f2[1]) >> 1; + } + + /* Convert polynomial coefficients to LPC coefficients */ + for (i = 0; i < LPC_ORDER / 2; i++) { + int64_t ff1 = f1[i + 1] + f1[i]; + int64_t ff2 = f2[i + 1] - f2[i]; + + lpc[i] = av_clipl_int32(((ff1 + ff2) << 3) + + (1 << 15)) >> 16; + lpc[LPC_ORDER - i - 1] = av_clipl_int32(((ff1 - ff2) << 3) + + (1 << 15)) >> 16; + } +} + +void ff_g723_1_lsp_interpolate(int16_t *lpc, int16_t *cur_lsp, + int16_t *prev_lsp) +{ + int i; + int16_t *lpc_ptr = lpc; + + /* cur_lsp * 0.25 + prev_lsp * 0.75 */ + ff_acelp_weighted_vector_sum(lpc, cur_lsp, prev_lsp, + 4096, 12288, 1 << 13, 14, LPC_ORDER); + ff_acelp_weighted_vector_sum(lpc + LPC_ORDER, cur_lsp, prev_lsp, + 8192, 8192, 1 << 13, 14, LPC_ORDER); + ff_acelp_weighted_vector_sum(lpc + 2 * LPC_ORDER, cur_lsp, prev_lsp, + 12288, 4096, 1 << 13, 14, LPC_ORDER); + memcpy(lpc + 3 * LPC_ORDER, cur_lsp, LPC_ORDER * sizeof(*lpc)); + + for (i = 0; i < SUBFRAMES; i++) { + lsp2lpc(lpc_ptr); + lpc_ptr += LPC_ORDER; + } +} + +void ff_g723_1_inverse_quant(int16_t *cur_lsp, int16_t *prev_lsp, + uint8_t *lsp_index, int bad_frame) +{ + int min_dist, pred; + int i, j, temp, stable; + + /* Check for frame erasure */ + if (!bad_frame) { + min_dist = 0x100; + pred = 12288; + } else { + min_dist = 0x200; + pred = 23552; + lsp_index[0] = lsp_index[1] = lsp_index[2] = 0; + } + + /* Get the VQ table entry corresponding to the transmitted index */ + cur_lsp[0] = lsp_band0[lsp_index[0]][0]; + cur_lsp[1] = lsp_band0[lsp_index[0]][1]; + cur_lsp[2] = lsp_band0[lsp_index[0]][2]; + cur_lsp[3] = lsp_band1[lsp_index[1]][0]; + cur_lsp[4] = lsp_band1[lsp_index[1]][1]; + cur_lsp[5] = lsp_band1[lsp_index[1]][2]; + cur_lsp[6] = lsp_band2[lsp_index[2]][0]; + cur_lsp[7] = lsp_band2[lsp_index[2]][1]; + cur_lsp[8] = lsp_band2[lsp_index[2]][2]; + cur_lsp[9] = lsp_band2[lsp_index[2]][3]; + + /* Add predicted vector & DC component to the previously quantized vector */ + for (i = 0; i < LPC_ORDER; i++) { + temp = ((prev_lsp[i] - dc_lsp[i]) * pred + (1 << 14)) >> 15; + cur_lsp[i] += dc_lsp[i] + temp; + } + + for (i = 0; i < LPC_ORDER; i++) { + cur_lsp[0] = FFMAX(cur_lsp[0], 0x180); + cur_lsp[LPC_ORDER - 1] = FFMIN(cur_lsp[LPC_ORDER - 1], 0x7e00); + + /* Stability check */ + for (j = 1; j < LPC_ORDER; j++) { + temp = min_dist + cur_lsp[j - 1] - cur_lsp[j]; + if (temp > 0) { + temp >>= 1; + cur_lsp[j - 1] -= temp; + cur_lsp[j] += temp; + } + } + stable = 1; + for (j = 1; j < LPC_ORDER; j++) { + temp = cur_lsp[j - 1] + min_dist - cur_lsp[j] - 4; + if (temp > 0) { + stable = 0; + break; + } + } + if (stable) + break; + } + if (!stable) + memcpy(cur_lsp, prev_lsp, LPC_ORDER * sizeof(*cur_lsp)); +} -- cgit v1.2.3