/* * G.729 decoder * Copyright (c) 2008 Vladimir Voroshilov * * This file is part of FFmpeg. * * FFmpeg 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. * * FFmpeg 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 FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include #include #include #include #include #include #include #include "avcodec.h" #include "libavutil/avutil.h" #include "bitstream.h" /** * minimum quantized LSF value (3.2.4) * 0.005 in Q13 */ #define LSFQ_MIN 40 /** * maximum quantized LSF value (3.2.4) * 3.135 in Q13 */ #define LSFQ_MAX 25681 /** * minimum LSF distance (3.2.4) * 0.0391 in Q13 */ #define LSFQ_DIFF_MIN 321 /** * minimum gain pitch value (3.8, Equation 47) * 0.2 in (1.14) */ #define SHARP_MIN 3277 /** * maximum gain pitch value (3.8, Equation 47) * (EE) This does not comply with the specification. * Specification says about 0.8, which should be * 13107 in (1.14), but reference C code uses * 13017 (equals to 0.7945) instead of it. */ #define SHARP_MAX 13017 /** * \brief pseudo random number generator */ static inline uint16_t g729_random(uint16_t value) { return 31821 * value + 13849; } /** * Get parity bit of bit 2..7 */ static inline int g729_get_parity(uint8_t value) { return (0x6996966996696996ULL >> (value >> 2)) & 1; } ff_acelp_weighted_vector_sum( fc + pitch_delay_int[i], fc + pitch_delay_int[i], fc, 1 << 14, av_clip(ctx->gain_pitch, SHARP_MIN, SHARP_MAX), 0, 14, ctx->subframe_size - pitch_delay_int[i]); ctx->gain_pitch = cb_gain_1st_8k[parm->gc_1st_index[i]][0] + cb_gain_2nd_8k[parm->gc_2nd_index[i]][0]; gain_corr_factor = cb_gain_1st_8k[parm->gc_1st_index[i]][1] + cb_gain_2nd_8k[parm->gc_2nd_index[i]][1]; ff_acelp_weighted_vector_sum( ctx->exc + i * ctx->subframe_size, ctx->exc + i * ctx->subframe_size, fc, (!voicing && ctx->frame_erasure) ? 0 : ctx->gain_pitch, ( voicing && ctx->frame_erasure) ? 0 : ctx->gain_code, 1<<13, 14, ctx->subframe_size); AVCodec g729_decoder = { "g729", CODEC_TYPE_AUDIO, CODEC_ID_G729, sizeof(G729_Context), ff_g729_decoder_init, NULL, NULL, ff_g729_decode_frame, .long_name = NULL_IF_CONFIG_SMALL("G.729"), };