| 1 | /* |
| 2 | * Copyright (c) 2012 |
| 3 | * MIPS Technologies, Inc., California. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * 3. Neither the name of the MIPS Technologies, Inc., nor the names of its |
| 14 | * contributors may be used to endorse or promote products derived from |
| 15 | * this software without specific prior written permission. |
| 16 | * |
| 17 | * THIS SOFTWARE IS PROVIDED BY THE MIPS TECHNOLOGIES, INC. ``AS IS'' AND |
| 18 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| 19 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| 20 | * ARE DISCLAIMED. IN NO EVENT SHALL THE MIPS TECHNOLOGIES, INC. BE LIABLE |
| 21 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| 22 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| 23 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| 24 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| 25 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| 26 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| 27 | * SUCH DAMAGE. |
| 28 | * |
| 29 | * Author: Stanislav Ocovaj (socovaj@mips.com) |
| 30 | * |
| 31 | * AC3 fixed-point decoder for MIPS platforms |
| 32 | * |
| 33 | * This file is part of FFmpeg. |
| 34 | * |
| 35 | * FFmpeg is free software; you can redistribute it and/or |
| 36 | * modify it under the terms of the GNU Lesser General Public |
| 37 | * License as published by the Free Software Foundation; either |
| 38 | * version 2.1 of the License, or (at your option) any later version. |
| 39 | * |
| 40 | * FFmpeg is distributed in the hope that it will be useful, |
| 41 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 42 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 43 | * Lesser General Public License for more details. |
| 44 | * |
| 45 | * You should have received a copy of the GNU Lesser General Public |
| 46 | * License along with FFmpeg; if not, write to the Free Software |
| 47 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 48 | */ |
| 49 | |
| 50 | #define FFT_FLOAT 0 |
| 51 | #define USE_FIXED 1 |
| 52 | #define FFT_FIXED_32 1 |
| 53 | #include "ac3dec.h" |
| 54 | |
| 55 | |
| 56 | static const int end_freq_inv_tab[8] = |
| 57 | { |
| 58 | 50529027, 44278013, 39403370, 32292987, 27356480, 23729101, 20951060, 18755316 |
| 59 | }; |
| 60 | |
| 61 | static void scale_coefs ( |
| 62 | int32_t *dst, |
| 63 | const int32_t *src, |
| 64 | int dynrng, |
| 65 | int len) |
| 66 | { |
| 67 | int i, shift, round; |
| 68 | int16_t mul; |
| 69 | int temp, temp1, temp2, temp3, temp4, temp5, temp6, temp7; |
| 70 | |
| 71 | mul = (dynrng & 0x1f) + 0x20; |
| 72 | shift = 4 - ((dynrng << 23) >> 28); |
| 73 | if (shift > 0 ) { |
| 74 | round = 1 << (shift-1); |
| 75 | for (i=0; i<len; i+=8) { |
| 76 | |
| 77 | temp = src[i] * mul; |
| 78 | temp1 = src[i+1] * mul; |
| 79 | temp = temp + round; |
| 80 | temp2 = src[i+2] * mul; |
| 81 | |
| 82 | temp1 = temp1 + round; |
| 83 | dst[i] = temp >> shift; |
| 84 | temp3 = src[i+3] * mul; |
| 85 | temp2 = temp2 + round; |
| 86 | |
| 87 | dst[i+1] = temp1 >> shift; |
| 88 | temp4 = src[i + 4] * mul; |
| 89 | temp3 = temp3 + round; |
| 90 | dst[i+2] = temp2 >> shift; |
| 91 | |
| 92 | temp5 = src[i+5] * mul; |
| 93 | temp4 = temp4 + round; |
| 94 | dst[i+3] = temp3 >> shift; |
| 95 | temp6 = src[i+6] * mul; |
| 96 | |
| 97 | dst[i+4] = temp4 >> shift; |
| 98 | temp5 = temp5 + round; |
| 99 | temp7 = src[i+7] * mul; |
| 100 | temp6 = temp6 + round; |
| 101 | |
| 102 | dst[i+5] = temp5 >> shift; |
| 103 | temp7 = temp7 + round; |
| 104 | dst[i+6] = temp6 >> shift; |
| 105 | dst[i+7] = temp7 >> shift; |
| 106 | |
| 107 | } |
| 108 | } else { |
| 109 | shift = -shift; |
| 110 | for (i=0; i<len; i+=8) { |
| 111 | |
| 112 | temp = src[i] * mul; |
| 113 | temp1 = src[i+1] * mul; |
| 114 | temp2 = src[i+2] * mul; |
| 115 | |
| 116 | dst[i] = temp << shift; |
| 117 | temp3 = src[i+3] * mul; |
| 118 | |
| 119 | dst[i+1] = temp1 << shift; |
| 120 | temp4 = src[i + 4] * mul; |
| 121 | dst[i+2] = temp2 << shift; |
| 122 | |
| 123 | temp5 = src[i+5] * mul; |
| 124 | dst[i+3] = temp3 << shift; |
| 125 | temp6 = src[i+6] * mul; |
| 126 | |
| 127 | dst[i+4] = temp4 << shift; |
| 128 | temp7 = src[i+7] * mul; |
| 129 | |
| 130 | dst[i+5] = temp5 << shift; |
| 131 | dst[i+6] = temp6 << shift; |
| 132 | dst[i+7] = temp7 << shift; |
| 133 | |
| 134 | } |
| 135 | } |
| 136 | } |
| 137 | |
| 138 | /** |
| 139 | * Downmix samples from original signal to stereo or mono (this is for 16-bit samples |
| 140 | * and fixed point decoder - original (for 32-bit samples) is in ac3dsp.c). |
| 141 | */ |
| 142 | static void ac3_downmix_c_fixed16(int16_t **samples, int16_t (*matrix)[2], |
| 143 | int out_ch, int in_ch, int len) |
| 144 | { |
| 145 | int i, j; |
| 146 | int v0, v1; |
| 147 | if (out_ch == 2) { |
| 148 | for (i = 0; i < len; i++) { |
| 149 | v0 = v1 = 0; |
| 150 | for (j = 0; j < in_ch; j++) { |
| 151 | v0 += samples[j][i] * matrix[j][0]; |
| 152 | v1 += samples[j][i] * matrix[j][1]; |
| 153 | } |
| 154 | samples[0][i] = (v0+2048)>>12; |
| 155 | samples[1][i] = (v1+2048)>>12; |
| 156 | } |
| 157 | } else if (out_ch == 1) { |
| 158 | for (i = 0; i < len; i++) { |
| 159 | v0 = 0; |
| 160 | for (j = 0; j < in_ch; j++) |
| 161 | v0 += samples[j][i] * matrix[j][0]; |
| 162 | samples[0][i] = (v0+2048)>>12; |
| 163 | } |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | #include "ac3dec.c" |
| 168 | |
| 169 | static const AVOption options[] = { |
| 170 | { "drc_scale", "percentage of dynamic range compression to apply", OFFSET(drc_scale), AV_OPT_TYPE_FLOAT, {.dbl = 1.0}, 0.0, 6.0, PAR }, |
| 171 | { "heavy_compr", "heavy dynamic range compression enabled", OFFSET(heavy_compression), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, PAR }, |
| 172 | { NULL}, |
| 173 | }; |
| 174 | |
| 175 | static const AVClass ac3_decoder_class = { |
| 176 | .class_name = "Fixed-Point AC-3 Decoder", |
| 177 | .item_name = av_default_item_name, |
| 178 | .option = options, |
| 179 | .version = LIBAVUTIL_VERSION_INT, |
| 180 | }; |
| 181 | |
| 182 | AVCodec ff_ac3_fixed_decoder = { |
| 183 | .name = "ac3_fixed", |
| 184 | .type = AVMEDIA_TYPE_AUDIO, |
| 185 | .id = AV_CODEC_ID_AC3, |
| 186 | .priv_data_size = sizeof (AC3DecodeContext), |
| 187 | .init = ac3_decode_init, |
| 188 | .close = ac3_decode_end, |
| 189 | .decode = ac3_decode_frame, |
| 190 | .capabilities = CODEC_CAP_DR1, |
| 191 | .long_name = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"), |
| 192 | .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P, |
| 193 | AV_SAMPLE_FMT_NONE }, |
| 194 | .priv_class = &ac3_decoder_class, |
| 195 | }; |