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avformat/mpeg: demux ivtv captions
[ffmpeg.git] / libavcodec / ac3enc.c
blob36492898652132eee3577907be5a785f079441ea
1 /*
2 * The simplest AC-3 encoder
3 * Copyright (c) 2000 Fabrice Bellard
4 * Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
5 * Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de>
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24 /**
25 * @file
26 * The simplest AC-3 encoder.
27 */
28
29 #include <stdint.h>
30
31 #include "libavutil/attributes.h"
32 #include "libavutil/avassert.h"
33 #include "libavutil/channel_layout.h"
34 #include "libavutil/crc.h"
35 #include "libavutil/emms.h"
36 #include "libavutil/internal.h"
37 #include "libavutil/mem.h"
38 #include "libavutil/mem_internal.h"
39 #include "libavutil/opt.h"
40 #include "libavutil/thread.h"
41 #include "avcodec.h"
42 #include "codec_internal.h"
43 #include "config_components.h"
44 #include "encode.h"
45 #include "me_cmp.h"
46 #include "put_bits.h"
47 #include "audiodsp.h"
48 #include "ac3dsp.h"
49 #include "ac3.h"
50 #include "ac3defs.h"
51 #include "ac3tab.h"
52 #include "ac3enc.h"
53 #include "eac3enc.h"
54
55 #define SAMPLETYPE_SIZE(ctx) (sizeof(float) == sizeof(int32_t) ? sizeof(float) : \
56 (ctx)->fixed_point ? sizeof(int32_t) : sizeof(float))
57
58 typedef struct AC3Mant {
59 int16_t *qmant1_ptr, *qmant2_ptr, *qmant4_ptr; ///< mantissa pointers for bap=1,2,4
60 int mant1_cnt, mant2_cnt, mant4_cnt; ///< mantissa counts for bap=1,2,4
61 } AC3Mant;
62
63 #define CMIXLEV_NUM_OPTIONS 3
64 static const float cmixlev_options[CMIXLEV_NUM_OPTIONS] = {
65 LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB
66 };
67
68 #define SURMIXLEV_NUM_OPTIONS 3
69 static const float surmixlev_options[SURMIXLEV_NUM_OPTIONS] = {
70 LEVEL_MINUS_3DB, LEVEL_MINUS_6DB, LEVEL_ZERO
71 };
72
73 #define EXTMIXLEV_NUM_OPTIONS 8
74 static const float extmixlev_options[EXTMIXLEV_NUM_OPTIONS] = {
75 LEVEL_PLUS_3DB, LEVEL_PLUS_1POINT5DB, LEVEL_ONE, LEVEL_MINUS_1POINT5DB,
76 LEVEL_MINUS_3DB, LEVEL_MINUS_4POINT5DB, LEVEL_MINUS_6DB, LEVEL_ZERO
77 };
78
79 /* The first two options apply only to the AC-3 encoders;
80 * the rest is also valid for EAC-3. When modifying it,
81 * it might be necessary to adapt said offset in eac3enc.c. */
82 #define OFFSET(param) offsetof(AC3EncodeContext, options.param)
83 #define AC3ENC_PARAM (AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM)
84 const AVOption ff_ac3_enc_options[] = {
85 /* AC-3 downmix levels */
86 {"center_mixlev", "Center Mix Level", OFFSET(center_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = LEVEL_MINUS_4POINT5DB }, 0.0, 1.0, AC3ENC_PARAM},
87 {"surround_mixlev", "Surround Mix Level", OFFSET(surround_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = LEVEL_MINUS_6DB }, 0.0, 1.0, AC3ENC_PARAM},
88 /* audio production information */
89 {"mixing_level", "Mixing Level", OFFSET(mixing_level), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, 111, AC3ENC_PARAM},
90 {"room_type", "Room Type", OFFSET(room_type), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_SMALL_ROOM, AC3ENC_PARAM, .unit = "room_type"},
91 {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "room_type"},
92 {"large", "Large Room", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_LARGE_ROOM }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "room_type"},
93 {"small", "Small Room", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_SMALL_ROOM }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "room_type"},
94 /* Metadata Options */
95 {"per_frame_metadata", "Allow Changing Metadata Per-Frame", OFFSET(allow_per_frame_metadata), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, AC3ENC_PARAM},
96 {"copyright", "Copyright Bit", OFFSET(copyright), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, 1, AC3ENC_PARAM},
97 {"dialnorm", "Dialogue Level (dB)", OFFSET(dialogue_level), AV_OPT_TYPE_INT, {.i64 = -31 }, -31, -1, AC3ENC_PARAM},
98 {"dsur_mode", "Dolby Surround Mode", OFFSET(dolby_surround_mode), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_MODE_ON, AC3ENC_PARAM, .unit = "dsur_mode"},
99 {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsur_mode"},
100 {"on", "Dolby Surround Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_ON }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsur_mode"},
101 {"off", "Not Dolby Surround Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_OFF }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsur_mode"},
102 {"original", "Original Bit Stream", OFFSET(original), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, 1, AC3ENC_PARAM},
103 /* extended bitstream information */
104 {"dmix_mode", "Preferred Stereo Downmix Mode", OFFSET(preferred_stereo_downmix), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_DOWNMIX_DPLII, AC3ENC_PARAM, .unit = "dmix_mode"},
105 {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dmix_mode"},
106 {"ltrt", "Lt/Rt Downmix Preferred", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DOWNMIX_LTRT }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dmix_mode"},
107 {"loro", "Lo/Ro Downmix Preferred", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DOWNMIX_LORO }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dmix_mode"},
108 {"dplii", "Dolby Pro Logic II Downmix Preferred", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DOWNMIX_DPLII }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dmix_mode"},
109 {"ltrt_cmixlev", "Lt/Rt Center Mix Level", OFFSET(ltrt_center_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, AC3ENC_PARAM},
110 {"ltrt_surmixlev", "Lt/Rt Surround Mix Level", OFFSET(ltrt_surround_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, AC3ENC_PARAM},
111 {"loro_cmixlev", "Lo/Ro Center Mix Level", OFFSET(loro_center_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, AC3ENC_PARAM},
112 {"loro_surmixlev", "Lo/Ro Surround Mix Level", OFFSET(loro_surround_mix_level), AV_OPT_TYPE_FLOAT, {.dbl = -1.0 }, -1.0, 2.0, AC3ENC_PARAM},
113 {"dsurex_mode", "Dolby Surround EX Mode", OFFSET(dolby_surround_ex_mode), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_DSUREX_DPLIIZ, AC3ENC_PARAM, .unit = "dsurex_mode"},
114 {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsurex_mode"},
115 {"on", "Dolby Surround EX Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_ON }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsurex_mode"},
116 {"off", "Not Dolby Surround EX Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_OFF }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsurex_mode"},
117 {"dpliiz", "Dolby Pro Logic IIz-encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_DSUREX_DPLIIZ }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dsurex_mode"},
118 {"dheadphone_mode", "Dolby Headphone Mode", OFFSET(dolby_headphone_mode), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_MODE_ON, AC3ENC_PARAM, .unit = "dheadphone_mode"},
119 {"notindicated", "Not Indicated (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_NOT_INDICATED }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dheadphone_mode"},
120 {"on", "Dolby Headphone Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_ON }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dheadphone_mode"},
121 {"off", "Not Dolby Headphone Encoded", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_MODE_OFF }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "dheadphone_mode"},
122 {"ad_conv_type", "A/D Converter Type", OFFSET(ad_converter_type), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_NONE }, AC3ENC_OPT_NONE, AC3ENC_OPT_ADCONV_HDCD, AC3ENC_PARAM, .unit = "ad_conv_type"},
123 {"standard", "Standard (default)", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_ADCONV_STANDARD }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "ad_conv_type"},
124 {"hdcd", "HDCD", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_ADCONV_HDCD }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "ad_conv_type"},
125 /* Other Encoding Options */
126 {"stereo_rematrixing", "Stereo Rematrixing", OFFSET(stereo_rematrixing), AV_OPT_TYPE_BOOL, {.i64 = 1 }, 0, 1, AC3ENC_PARAM},
127 {"channel_coupling", "Channel Coupling", OFFSET(channel_coupling), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_AUTO }, AC3ENC_OPT_AUTO, AC3ENC_OPT_ON, AC3ENC_PARAM, .unit = "channel_coupling"},
128 {"auto", "Selected by the Encoder", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_AUTO }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "channel_coupling"},
129 {"cpl_start_band", "Coupling Start Band", OFFSET(cpl_start), AV_OPT_TYPE_INT, {.i64 = AC3ENC_OPT_AUTO }, AC3ENC_OPT_AUTO, 15, AC3ENC_PARAM, .unit = "cpl_start_band"},
130 {"auto", "Selected by the Encoder", 0, AV_OPT_TYPE_CONST, {.i64 = AC3ENC_OPT_AUTO }, INT_MIN, INT_MAX, AC3ENC_PARAM, .unit = "cpl_start_band"},
131 {NULL}
132 };
133
134 const AVClass ff_ac3enc_class = {
135 .class_name = "AC-3 Encoder",
136 .item_name = av_default_item_name,
137 .option = ff_ac3_enc_options,
138 .version = LIBAVUTIL_VERSION_INT,
139 };
140
141 const FFCodecDefault ff_ac3_enc_defaults[] = {
142 { "b", "0" },
143 { NULL }
144 };
145
146 /**
147 * LUT for number of exponent groups.
148 * exponent_group_tab[coupling][exponent strategy-1][number of coefficients]
149 */
150 static uint8_t exponent_group_tab[2][3][256];
151
152
153 /**
154 * List of supported channel layouts.
155 */
156 const AVChannelLayout ff_ac3_ch_layouts[19] = {
157 AV_CHANNEL_LAYOUT_MONO,
158 AV_CHANNEL_LAYOUT_STEREO,
159 AV_CHANNEL_LAYOUT_2_1,
160 AV_CHANNEL_LAYOUT_SURROUND,
161 AV_CHANNEL_LAYOUT_2_2,
162 AV_CHANNEL_LAYOUT_QUAD,
163 AV_CHANNEL_LAYOUT_4POINT0,
164 AV_CHANNEL_LAYOUT_5POINT0,
165 AV_CHANNEL_LAYOUT_5POINT0_BACK,
166 {
167 .nb_channels = 2,
168 .order = AV_CHANNEL_ORDER_NATIVE,
169 .u.mask = AV_CH_LAYOUT_MONO | AV_CH_LOW_FREQUENCY,
170 },
171 {
172 .nb_channels = 3,
173 .order = AV_CHANNEL_ORDER_NATIVE,
174 .u.mask = AV_CH_LAYOUT_STEREO | AV_CH_LOW_FREQUENCY,
175 },
176 {
177 .nb_channels = 4,
178 .order = AV_CHANNEL_ORDER_NATIVE,
179 .u.mask = AV_CH_LAYOUT_2_1 | AV_CH_LOW_FREQUENCY,
180 },
181 {
182 .nb_channels = 4,
183 .order = AV_CHANNEL_ORDER_NATIVE,
184 .u.mask = AV_CH_LAYOUT_SURROUND | AV_CH_LOW_FREQUENCY,
185 },
186 {
187 .nb_channels = 5,
188 .order = AV_CHANNEL_ORDER_NATIVE,
189 .u.mask = AV_CH_LAYOUT_4POINT0 | AV_CH_LOW_FREQUENCY,
190 },
191 AV_CHANNEL_LAYOUT_5POINT1,
192 AV_CHANNEL_LAYOUT_5POINT1_BACK,
193 { 0 },
194 };
195
196 /**
197 * Table to remap channels from SMPTE order to AC-3 order.
198 * [channel_mode][lfe][ch]
199 */
200 static const uint8_t ac3_enc_channel_map[8][2][6] = {
201 COMMON_CHANNEL_MAP
202 { { 0, 1, 2, 3, }, { 0, 1, 3, 4, 2, } },
203 { { 0, 2, 1, 3, 4, }, { 0, 2, 1, 4, 5, 3 } },
204 };
205
206 /**
207 * LUT to select the bandwidth code based on the bit rate, sample rate, and
208 * number of full-bandwidth channels.
209 * bandwidth_tab[fbw_channels-1][sample rate code][bit rate code]
210 */
211 static const uint8_t ac3_bandwidth_tab[5][3][19] = {
212 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640
213
214 { { 0, 0, 0, 12, 16, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
215 { 0, 0, 0, 16, 20, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
216 { 0, 0, 0, 32, 40, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
217
218 { { 0, 0, 0, 0, 0, 0, 0, 20, 24, 32, 48, 48, 48, 48, 48, 48, 48, 48, 48 },
219 { 0, 0, 0, 0, 0, 0, 4, 24, 28, 36, 56, 56, 56, 56, 56, 56, 56, 56, 56 },
220 { 0, 0, 0, 0, 0, 0, 20, 44, 52, 60, 60, 60, 60, 60, 60, 60, 60, 60, 60 } },
221
222 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 24, 32, 40, 48, 48, 48, 48, 48, 48 },
223 { 0, 0, 0, 0, 0, 0, 0, 0, 4, 20, 28, 36, 44, 56, 56, 56, 56, 56, 56 },
224 { 0, 0, 0, 0, 0, 0, 0, 0, 20, 40, 48, 60, 60, 60, 60, 60, 60, 60, 60 } },
225
226 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 32, 48, 48, 48, 48, 48, 48 },
227 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 16, 28, 36, 56, 56, 56, 56, 56, 56 },
228 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 32, 48, 60, 60, 60, 60, 60, 60, 60 } },
229
230 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 20, 32, 40, 48, 48, 48, 48 },
231 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 24, 36, 44, 56, 56, 56, 56 },
232 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 28, 44, 60, 60, 60, 60, 60, 60 } }
233 };
234
235
236 /**
237 * LUT to select the coupling start band based on the bit rate, sample rate, and
238 * number of full-bandwidth channels. -1 = coupling off
239 * ac3_coupling_start_tab[channel_mode-2][sample rate code][bit rate code]
240 *
241 * TODO: more testing for optimal parameters.
242 * multi-channel tests at 44.1kHz and 32kHz.
243 */
244 static const int8_t ac3_coupling_start_tab[6][3][19] = {
245 // 32 40 48 56 64 80 96 112 128 160 192 224 256 320 384 448 512 576 640
246
247 // 2/0
248 { { 0, 0, 0, 0, 0, 0, 0, 1, 1, 7, 8, 11, 12, -1, -1, -1, -1, -1, -1 },
249 { 0, 0, 0, 0, 0, 0, 1, 3, 5, 7, 10, 12, 13, -1, -1, -1, -1, -1, -1 },
250 { 0, 0, 0, 0, 1, 2, 2, 9, 13, 15, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
251
252 // 3/0
253 { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
254 { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
255 { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
256
257 // 2/1 - untested
258 { { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
259 { 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 6, 9, 11, 12, 13, -1, -1, -1, -1 },
260 { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
261
262 // 3/1
263 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
264 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
265 { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
266
267 // 2/2 - untested
268 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
269 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 2, 10, 11, 11, 12, 12, 14, -1 },
270 { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
271
272 // 3/2
273 { { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },
274 { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 6, 8, 11, 12, 12, -1, -1 },
275 { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 } },
276 };
277
278
279 #define FLT_OPTION_THRESHOLD 0.01
280
281 static int validate_float_option(float v, const float *v_list, int v_list_size)
282 {
283 int i;
284
285 for (i = 0; i < v_list_size; i++) {
286 if (v < (v_list[i] + FLT_OPTION_THRESHOLD) &&
287 v > (v_list[i] - FLT_OPTION_THRESHOLD))
288 break;
289 }
290 if (i == v_list_size)
291 return AVERROR(EINVAL);
292
293 return i;
294 }
295
296
297 static void validate_mix_level(void *log_ctx, const char *opt_name,
298 float *opt_param, const float *list,
299 int list_size, int default_value, int min_value,
300 int *ctx_param)
301 {
302 int mixlev = validate_float_option(*opt_param, list, list_size);
303 if (mixlev < min_value) {
304 mixlev = default_value;
305 if (*opt_param >= 0.0) {
306 av_log(log_ctx, AV_LOG_WARNING, "requested %s is not valid. using "
307 "default value: %0.3f\n", opt_name, list[mixlev]);
308 }
309 }
310 *opt_param = list[mixlev];
311 *ctx_param = mixlev;
312 }
313
314
315 /**
316 * Validate metadata options as set by AVOption system.
317 * These values can optionally be changed per-frame.
318 *
319 * @param s AC-3 encoder private context
320 */
321 static int ac3_validate_metadata(AC3EncodeContext *s)
322 {
323 AVCodecContext *avctx = s->avctx;
324 AC3EncOptions *opt = &s->options;
325
326 opt->audio_production_info = 0;
327 opt->extended_bsi_1 = 0;
328 opt->extended_bsi_2 = 0;
329 opt->eac3_mixing_metadata = 0;
330 opt->eac3_info_metadata = 0;
331
332 /* determine mixing metadata / xbsi1 use */
333 if (s->channel_mode > AC3_CHMODE_STEREO && opt->preferred_stereo_downmix != AC3ENC_OPT_NONE) {
334 opt->extended_bsi_1 = 1;
335 opt->eac3_mixing_metadata = 1;
336 }
337 if (s->has_center &&
338 (opt->ltrt_center_mix_level >= 0 || opt->loro_center_mix_level >= 0)) {
339 opt->extended_bsi_1 = 1;
340 opt->eac3_mixing_metadata = 1;
341 }
342 if (s->has_surround &&
343 (opt->ltrt_surround_mix_level >= 0 || opt->loro_surround_mix_level >= 0)) {
344 opt->extended_bsi_1 = 1;
345 opt->eac3_mixing_metadata = 1;
346 }
347
348 if (s->eac3) {
349 /* determine info metadata use */
350 if (avctx->audio_service_type != AV_AUDIO_SERVICE_TYPE_MAIN)
351 opt->eac3_info_metadata = 1;
352 if (opt->copyright != AC3ENC_OPT_NONE || opt->original != AC3ENC_OPT_NONE)
353 opt->eac3_info_metadata = 1;
354 if (s->channel_mode == AC3_CHMODE_STEREO &&
355 (opt->dolby_headphone_mode != AC3ENC_OPT_NONE || opt->dolby_surround_mode != AC3ENC_OPT_NONE))
356 opt->eac3_info_metadata = 1;
357 if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
358 opt->eac3_info_metadata = 1;
359 if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE ||
360 opt->ad_converter_type != AC3ENC_OPT_NONE) {
361 opt->audio_production_info = 1;
362 opt->eac3_info_metadata = 1;
363 }
364 } else {
365 /* determine audio production info use */
366 if (opt->mixing_level != AC3ENC_OPT_NONE || opt->room_type != AC3ENC_OPT_NONE)
367 opt->audio_production_info = 1;
368
369 /* determine xbsi2 use */
370 if (s->channel_mode >= AC3_CHMODE_2F2R && opt->dolby_surround_ex_mode != AC3ENC_OPT_NONE)
371 opt->extended_bsi_2 = 1;
372 if (s->channel_mode == AC3_CHMODE_STEREO && opt->dolby_headphone_mode != AC3ENC_OPT_NONE)
373 opt->extended_bsi_2 = 1;
374 if (opt->ad_converter_type != AC3ENC_OPT_NONE)
375 opt->extended_bsi_2 = 1;
376 }
377
378 /* validate AC-3 mixing levels */
379 if (!s->eac3) {
380 if (s->has_center) {
381 validate_mix_level(avctx, "center_mix_level", &opt->center_mix_level,
382 cmixlev_options, CMIXLEV_NUM_OPTIONS, 1, 0,
383 &s->center_mix_level);
384 }
385 if (s->has_surround) {
386 validate_mix_level(avctx, "surround_mix_level", &opt->surround_mix_level,
387 surmixlev_options, SURMIXLEV_NUM_OPTIONS, 1, 0,
388 &s->surround_mix_level);
389 }
390 }
391
392 /* validate extended bsi 1 / mixing metadata */
393 if (opt->extended_bsi_1 || opt->eac3_mixing_metadata) {
394 /* default preferred stereo downmix */
395 if (opt->preferred_stereo_downmix == AC3ENC_OPT_NONE)
396 opt->preferred_stereo_downmix = AC3ENC_OPT_NOT_INDICATED;
397 if (!s->eac3 || s->has_center) {
398 /* validate Lt/Rt center mix level */
399 validate_mix_level(avctx, "ltrt_center_mix_level",
400 &opt->ltrt_center_mix_level, extmixlev_options,
401 EXTMIXLEV_NUM_OPTIONS, 5, 0,
402 &s->ltrt_center_mix_level);
403 /* validate Lo/Ro center mix level */
404 validate_mix_level(avctx, "loro_center_mix_level",
405 &opt->loro_center_mix_level, extmixlev_options,
406 EXTMIXLEV_NUM_OPTIONS, 5, 0,
407 &s->loro_center_mix_level);
408 }
409 if (!s->eac3 || s->has_surround) {
410 /* validate Lt/Rt surround mix level */
411 validate_mix_level(avctx, "ltrt_surround_mix_level",
412 &opt->ltrt_surround_mix_level, extmixlev_options,
413 EXTMIXLEV_NUM_OPTIONS, 6, 3,
414 &s->ltrt_surround_mix_level);
415 /* validate Lo/Ro surround mix level */
416 validate_mix_level(avctx, "loro_surround_mix_level",
417 &opt->loro_surround_mix_level, extmixlev_options,
418 EXTMIXLEV_NUM_OPTIONS, 6, 3,
419 &s->loro_surround_mix_level);
420 }
421 }
422
423 /* validate audio service type / channels combination */
424 if ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_KARAOKE &&
425 avctx->ch_layout.nb_channels == 1) ||
426 ((avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_COMMENTARY ||
427 avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_EMERGENCY ||
428 avctx->audio_service_type == AV_AUDIO_SERVICE_TYPE_VOICE_OVER)
429 && avctx->ch_layout.nb_channels > 1)) {
430 av_log(avctx, AV_LOG_ERROR, "invalid audio service type for the "
431 "specified number of channels\n");
432 return AVERROR(EINVAL);
433 }
434
435 /* validate extended bsi 2 / info metadata */
436 if (opt->extended_bsi_2 || opt->eac3_info_metadata) {
437 /* default dolby headphone mode */
438 if (opt->dolby_headphone_mode == AC3ENC_OPT_NONE)
439 opt->dolby_headphone_mode = AC3ENC_OPT_NOT_INDICATED;
440 /* default dolby surround ex mode */
441 if (opt->dolby_surround_ex_mode == AC3ENC_OPT_NONE)
442 opt->dolby_surround_ex_mode = AC3ENC_OPT_NOT_INDICATED;
443 /* default A/D converter type */
444 if (opt->ad_converter_type == AC3ENC_OPT_NONE)
445 opt->ad_converter_type = AC3ENC_OPT_ADCONV_STANDARD;
446 }
447
448 /* copyright & original defaults */
449 if (!s->eac3 || opt->eac3_info_metadata) {
450 /* default copyright */
451 if (opt->copyright == AC3ENC_OPT_NONE)
452 opt->copyright = AC3ENC_OPT_OFF;
453 /* default original */
454 if (opt->original == AC3ENC_OPT_NONE)
455 opt->original = AC3ENC_OPT_ON;
456 }
457
458 /* dolby surround mode default */
459 if (!s->eac3 || opt->eac3_info_metadata) {
460 if (opt->dolby_surround_mode == AC3ENC_OPT_NONE)
461 opt->dolby_surround_mode = AC3ENC_OPT_NOT_INDICATED;
462 }
463
464 /* validate audio production info */
465 if (opt->audio_production_info) {
466 if (opt->mixing_level == AC3ENC_OPT_NONE) {
467 av_log(avctx, AV_LOG_ERROR, "mixing_level must be set if "
468 "room_type is set\n");
469 return AVERROR(EINVAL);
470 }
471 if (opt->mixing_level < 80) {
472 av_log(avctx, AV_LOG_ERROR, "invalid mixing level. must be between "
473 "80dB and 111dB\n");
474 return AVERROR(EINVAL);
475 }
476 /* default room type */
477 if (opt->room_type == AC3ENC_OPT_NONE)
478 opt->room_type = AC3ENC_OPT_NOT_INDICATED;
479 }
480
481 /* set bitstream id for alternate bitstream syntax */
482 if (!s->eac3 && (opt->extended_bsi_1 || opt->extended_bsi_2))
483 s->bitstream_id = 6;
484
485 return 0;
486 }
487
488 /**
489 * Adjust the frame size to make the average bit rate match the target bit rate.
490 * This is only needed for 11025, 22050, and 44100 sample rates or any E-AC-3.
491 *
492 * @param s AC-3 encoder private context
493 */
494 static void ac3_adjust_frame_size(AC3EncodeContext *s)
495 {
496 while (s->bits_written >= s->bit_rate && s->samples_written >= s->sample_rate) {
497 s->bits_written -= s->bit_rate;
498 s->samples_written -= s->sample_rate;
499 }
500 s->frame_size = s->frame_size_min +
501 2 * (s->bits_written * s->sample_rate < s->samples_written * s->bit_rate);
502 s->bits_written += s->frame_size * 8;
503 s->samples_written += AC3_BLOCK_SIZE * s->num_blocks;
504 }
505
506 /**
507 * Set the initial coupling strategy parameters prior to coupling analysis.
508 *
509 * @param s AC-3 encoder private context
510 */
511 void ff_ac3_compute_coupling_strategy(AC3EncodeContext *s)
512 {
513 int blk, ch;
514 int got_cpl_snr;
515 int num_cpl_blocks;
516
517 /* set coupling use flags for each block/channel */
518 /* TODO: turn coupling on/off and adjust start band based on bit usage */
519 for (blk = 0; blk < s->num_blocks; blk++) {
520 AC3Block *block = &s->blocks[blk];
521 for (ch = 1; ch <= s->fbw_channels; ch++)
522 block->channel_in_cpl[ch] = s->cpl_on;
523 }
524
525 /* enable coupling for each block if at least 2 channels have coupling
526 enabled for that block */
527 got_cpl_snr = 0;
528 num_cpl_blocks = 0;
529 for (blk = 0; blk < s->num_blocks; blk++) {
530 AC3Block *block = &s->blocks[blk];
531 block->num_cpl_channels = 0;
532 for (ch = 1; ch <= s->fbw_channels; ch++)
533 block->num_cpl_channels += block->channel_in_cpl[ch];
534 block->cpl_in_use = block->num_cpl_channels > 1;
535 num_cpl_blocks += block->cpl_in_use;
536 if (!block->cpl_in_use) {
537 block->num_cpl_channels = 0;
538 for (ch = 1; ch <= s->fbw_channels; ch++)
539 block->channel_in_cpl[ch] = 0;
540 }
541
542 block->new_cpl_strategy = !blk;
543 if (blk) {
544 for (ch = 1; ch <= s->fbw_channels; ch++) {
545 if (block->channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
546 block->new_cpl_strategy = 1;
547 break;
548 }
549 }
550 }
551 block->new_cpl_leak = block->new_cpl_strategy;
552
553 if (!blk || (block->cpl_in_use && !got_cpl_snr)) {
554 block->new_snr_offsets = 1;
555 if (block->cpl_in_use)
556 got_cpl_snr = 1;
557 } else {
558 block->new_snr_offsets = 0;
559 }
560 }
561 if (!num_cpl_blocks)
562 s->cpl_on = 0;
563
564 /* set bandwidth for each channel */
565 for (blk = 0; blk < s->num_blocks; blk++) {
566 AC3Block *block = &s->blocks[blk];
567 for (ch = 1; ch <= s->fbw_channels; ch++) {
568 if (block->channel_in_cpl[ch])
569 block->end_freq[ch] = s->start_freq[CPL_CH];
570 else
571 block->end_freq[ch] = s->bandwidth_code * 3 + 73;
572 }
573 }
574 }
575
576
577 /**
578 * Apply stereo rematrixing to coefficients based on rematrixing flags.
579 *
580 * @param s AC-3 encoder private context
581 */
582 static void ac3_apply_rematrixing(AC3EncodeContext *s)
583 {
584 int nb_coefs;
585 int blk, bnd, i;
586 int start, end;
587 uint8_t *flags = NULL;
588
589 if (!s->rematrixing_enabled)
590 return;
591
592 for (blk = 0; blk < s->num_blocks; blk++) {
593 AC3Block *block = &s->blocks[blk];
594 if (block->new_rematrixing_strategy)
595 flags = block->rematrixing_flags;
596 nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
597 for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
598 if (flags[bnd]) {
599 start = ff_ac3_rematrix_band_tab[bnd];
600 end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
601 for (i = start; i < end; i++) {
602 int32_t lt = block->fixed_coef[1][i];
603 int32_t rt = block->fixed_coef[2][i];
604 block->fixed_coef[1][i] = (lt + rt) >> 1;
605 block->fixed_coef[2][i] = (lt - rt) >> 1;
606 }
607 }
608 }
609 }
610 }
611
612
613 /*
614 * Initialize exponent tables.
615 */
616 static av_cold void exponent_init(void)
617 {
618 int expstr, i, grpsize;
619
620 for (expstr = EXP_D15-1; expstr <= EXP_D45-1; expstr++) {
621 grpsize = 3 << expstr;
622 for (i = 12; i < 256; i++) {
623 exponent_group_tab[0][expstr][i] = (i + grpsize - 4) / grpsize;
624 exponent_group_tab[1][expstr][i] = (i ) / grpsize;
625 }
626 }
627 /* LFE */
628 exponent_group_tab[0][0][7] = 2;
629 }
630
631
632 /*
633 * Extract exponents from the MDCT coefficients.
634 */
635 static void extract_exponents(AC3EncodeContext *s)
636 {
637 int ch = !s->cpl_on;
638 int chan_size = AC3_MAX_COEFS * s->num_blocks * (s->channels - ch + 1);
639 AC3Block *block = &s->blocks[0];
640
641 s->ac3dsp.extract_exponents(block->exp[ch], block->fixed_coef[ch], chan_size);
642 }
643
644
645 /**
646 * Exponent Difference Threshold.
647 * New exponents are sent if their SAD exceed this number.
648 */
649 #define EXP_DIFF_THRESHOLD 500
650
651 /**
652 * Table used to select exponent strategy based on exponent reuse block interval.
653 */
654 static const uint8_t exp_strategy_reuse_tab[4][6] = {
655 { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
656 { EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
657 { EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15, EXP_D15 },
658 { EXP_D45, EXP_D25, EXP_D25, EXP_D15, EXP_D15, EXP_D15 }
659 };
660
661 /*
662 * Calculate exponent strategies for all channels.
663 * Array arrangement is reversed to simplify the per-channel calculation.
664 */
665 static void compute_exp_strategy(AC3EncodeContext *s)
666 {
667 int ch, blk, blk1;
668
669 for (ch = !s->cpl_on; ch <= s->fbw_channels; ch++) {
670 uint8_t *exp_strategy = s->exp_strategy[ch];
671 uint8_t *exp = s->blocks[0].exp[ch];
672 int exp_diff;
673
674 /* estimate if the exponent variation & decide if they should be
675 reused in the next frame */
676 exp_strategy[0] = EXP_NEW;
677 exp += AC3_MAX_COEFS;
678 for (blk = 1; blk < s->num_blocks; blk++, exp += AC3_MAX_COEFS) {
679 if (ch == CPL_CH) {
680 if (!s->blocks[blk-1].cpl_in_use) {
681 exp_strategy[blk] = EXP_NEW;
682 continue;
683 } else if (!s->blocks[blk].cpl_in_use) {
684 exp_strategy[blk] = EXP_REUSE;
685 continue;
686 }
687 } else if (s->blocks[blk].channel_in_cpl[ch] != s->blocks[blk-1].channel_in_cpl[ch]) {
688 exp_strategy[blk] = EXP_NEW;
689 continue;
690 }
691 exp_diff = s->mecc.sad[0](NULL, exp, exp - AC3_MAX_COEFS, 16, 16);
692 exp_strategy[blk] = EXP_REUSE;
693 if (ch == CPL_CH && exp_diff > (EXP_DIFF_THRESHOLD * (s->blocks[blk].end_freq[ch] - s->start_freq[ch]) / AC3_MAX_COEFS))
694 exp_strategy[blk] = EXP_NEW;
695 else if (ch > CPL_CH && exp_diff > EXP_DIFF_THRESHOLD)
696 exp_strategy[blk] = EXP_NEW;
697 }
698
699 /* now select the encoding strategy type : if exponents are often
700 recoded, we use a coarse encoding */
701 blk = 0;
702 while (blk < s->num_blocks) {
703 blk1 = blk + 1;
704 while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE)
705 blk1++;
706 exp_strategy[blk] = exp_strategy_reuse_tab[s->num_blks_code][blk1-blk-1];
707 blk = blk1;
708 }
709 }
710 if (s->lfe_on) {
711 ch = s->lfe_channel;
712 s->exp_strategy[ch][0] = EXP_D15;
713 for (blk = 1; blk < s->num_blocks; blk++)
714 s->exp_strategy[ch][blk] = EXP_REUSE;
715 }
716
717 /* for E-AC-3, determine frame exponent strategy */
718 if (CONFIG_EAC3_ENCODER && s->eac3)
719 ff_eac3_get_frame_exp_strategy(s);
720 }
721
722
723 /**
724 * Update the exponents so that they are the ones the decoder will decode.
725 *
726 * @param[in,out] exp array of exponents for 1 block in 1 channel
727 * @param nb_exps number of exponents in active bandwidth
728 * @param exp_strategy exponent strategy for the block
729 * @param cpl indicates if the block is in the coupling channel
730 */
731 static void encode_exponents_blk_ch(uint8_t *exp, int nb_exps, int exp_strategy,
732 int cpl)
733 {
734 int nb_groups, i, k;
735
736 nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_exps] * 3;
737
738 /* for each group, compute the minimum exponent */
739 switch(exp_strategy) {
740 case EXP_D25:
741 for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
742 uint8_t exp_min = exp[k];
743 if (exp[k+1] < exp_min)
744 exp_min = exp[k+1];
745 exp[i-cpl] = exp_min;
746 k += 2;
747 }
748 break;
749 case EXP_D45:
750 for (i = 1, k = 1-cpl; i <= nb_groups; i++) {
751 uint8_t exp_min = exp[k];
752 if (exp[k+1] < exp_min)
753 exp_min = exp[k+1];
754 if (exp[k+2] < exp_min)
755 exp_min = exp[k+2];
756 if (exp[k+3] < exp_min)
757 exp_min = exp[k+3];
758 exp[i-cpl] = exp_min;
759 k += 4;
760 }
761 break;
762 }
763
764 /* constraint for DC exponent */
765 if (!cpl && exp[0] > 15)
766 exp[0] = 15;
767
768 /* decrease the delta between each groups to within 2 so that they can be
769 differentially encoded */
770 for (i = 1; i <= nb_groups; i++)
771 exp[i] = FFMIN(exp[i], exp[i-1] + 2);
772 i--;
773 while (--i >= 0)
774 exp[i] = FFMIN(exp[i], exp[i+1] + 2);
775
776 if (cpl)
777 exp[-1] = exp[0] & ~1;
778
779 /* now we have the exponent values the decoder will see */
780 switch (exp_strategy) {
781 case EXP_D25:
782 for (i = nb_groups, k = (nb_groups * 2)-cpl; i > 0; i--) {
783 uint8_t exp1 = exp[i-cpl];
784 exp[k--] = exp1;
785 exp[k--] = exp1;
786 }
787 break;
788 case EXP_D45:
789 for (i = nb_groups, k = (nb_groups * 4)-cpl; i > 0; i--) {
790 exp[k] = exp[k-1] = exp[k-2] = exp[k-3] = exp[i-cpl];
791 k -= 4;
792 }
793 break;
794 }
795 }
796
797
798 /*
799 * Encode exponents from original extracted form to what the decoder will see.
800 * This copies and groups exponents based on exponent strategy and reduces
801 * deltas between adjacent exponent groups so that they can be differentially
802 * encoded.
803 */
804 static void encode_exponents(AC3EncodeContext *s)
805 {
806 int blk, blk1, ch, cpl;
807 uint8_t *exp, *exp_strategy;
808 int nb_coefs, num_reuse_blocks;
809
810 for (ch = !s->cpl_on; ch <= s->channels; ch++) {
811 exp = s->blocks[0].exp[ch] + s->start_freq[ch];
812 exp_strategy = s->exp_strategy[ch];
813
814 cpl = (ch == CPL_CH);
815 blk = 0;
816 while (blk < s->num_blocks) {
817 AC3Block *block = &s->blocks[blk];
818 if (cpl && !block->cpl_in_use) {
819 exp += AC3_MAX_COEFS;
820 blk++;
821 continue;
822 }
823 nb_coefs = block->end_freq[ch] - s->start_freq[ch];
824 blk1 = blk + 1;
825
826 /* count the number of EXP_REUSE blocks after the current block
827 and set exponent reference block numbers */
828 s->exp_ref_block[ch][blk] = blk;
829 while (blk1 < s->num_blocks && exp_strategy[blk1] == EXP_REUSE) {
830 s->exp_ref_block[ch][blk1] = blk;
831 blk1++;
832 }
833 num_reuse_blocks = blk1 - blk - 1;
834
835 /* for the EXP_REUSE case we select the min of the exponents */
836 s->ac3dsp.ac3_exponent_min(exp-s->start_freq[ch], num_reuse_blocks,
837 AC3_MAX_COEFS);
838
839 encode_exponents_blk_ch(exp, nb_coefs, exp_strategy[blk], cpl);
840
841 exp += AC3_MAX_COEFS * (num_reuse_blocks + 1);
842 blk = blk1;
843 }
844 }
845
846 /* reference block numbers have been changed, so reset ref_bap_set */
847 s->ref_bap_set = 0;
848 }
849
850
851 /*
852 * Count exponent bits based on bandwidth, coupling, and exponent strategies.
853 */
854 static int count_exponent_bits(AC3EncodeContext *s)
855 {
856 int blk, ch;
857 int nb_groups, bit_count;
858
859 bit_count = 0;
860 for (blk = 0; blk < s->num_blocks; blk++) {
861 AC3Block *block = &s->blocks[blk];
862 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
863 int exp_strategy = s->exp_strategy[ch][blk];
864 int cpl = (ch == CPL_CH);
865 int nb_coefs = block->end_freq[ch] - s->start_freq[ch];
866
867 if (exp_strategy == EXP_REUSE)
868 continue;
869
870 nb_groups = exponent_group_tab[cpl][exp_strategy-1][nb_coefs];
871 bit_count += 4 + (nb_groups * 7);
872 }
873 }
874
875 return bit_count;
876 }
877
878
879 /**
880 * Group exponents.
881 * 3 delta-encoded exponents are in each 7-bit group. The number of groups
882 * varies depending on exponent strategy and bandwidth.
883 *
884 * @param s AC-3 encoder private context
885 */
886 static void ac3_group_exponents(AC3EncodeContext *s)
887 {
888 int blk, ch, i, cpl;
889 int group_size, nb_groups;
890 uint8_t *p;
891 int delta0, delta1, delta2;
892 int exp0, exp1;
893
894 for (blk = 0; blk < s->num_blocks; blk++) {
895 AC3Block *block = &s->blocks[blk];
896 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
897 int exp_strategy = s->exp_strategy[ch][blk];
898 if (exp_strategy == EXP_REUSE)
899 continue;
900 cpl = (ch == CPL_CH);
901 group_size = exp_strategy + (exp_strategy == EXP_D45);
902 nb_groups = exponent_group_tab[cpl][exp_strategy-1][block->end_freq[ch]-s->start_freq[ch]];
903 p = block->exp[ch] + s->start_freq[ch] - cpl;
904
905 /* DC exponent */
906 exp1 = *p++;
907 block->grouped_exp[ch][0] = exp1;
908
909 /* remaining exponents are delta encoded */
910 for (i = 1; i <= nb_groups; i++) {
911 /* merge three delta in one code */
912 exp0 = exp1;
913 exp1 = p[0];
914 p += group_size;
915 delta0 = exp1 - exp0 + 2;
916 av_assert2(delta0 >= 0 && delta0 <= 4);
917
918 exp0 = exp1;
919 exp1 = p[0];
920 p += group_size;
921 delta1 = exp1 - exp0 + 2;
922 av_assert2(delta1 >= 0 && delta1 <= 4);
923
924 exp0 = exp1;
925 exp1 = p[0];
926 p += group_size;
927 delta2 = exp1 - exp0 + 2;
928 av_assert2(delta2 >= 0 && delta2 <= 4);
929
930 block->grouped_exp[ch][i] = ((delta0 * 5 + delta1) * 5) + delta2;
931 }
932 }
933 }
934 }
935
936
937 /**
938 * Calculate final exponents from the supplied MDCT coefficients and exponent shift.
939 * Extract exponents from MDCT coefficients, calculate exponent strategies,
940 * and encode final exponents.
941 *
942 * @param s AC-3 encoder private context
943 */
944 static void ac3_process_exponents(AC3EncodeContext *s)
945 {
946 extract_exponents(s);
947
948 compute_exp_strategy(s);
949
950 encode_exponents(s);
951
952 emms_c();
953 }
954
955
956 /*
957 * Count frame bits that are based solely on fixed parameters.
958 * This only has to be run once when the encoder is initialized.
959 */
960 static void count_frame_bits_fixed(AC3EncodeContext *s)
961 {
962 static const uint8_t frame_bits_inc[8] = { 0, 0, 2, 2, 2, 4, 2, 4 };
963 int blk;
964 int frame_bits;
965
966 /* assumptions:
967 * no dynamic range codes
968 * bit allocation parameters do not change between blocks
969 * no delta bit allocation
970 * no skipped data
971 * no auxiliary data
972 * no E-AC-3 metadata
973 */
974
975 /* header */
976 frame_bits = 16; /* sync info */
977 if (s->eac3) {
978 /* bitstream info header */
979 frame_bits += 35;
980 frame_bits += 1 + 1;
981 if (s->num_blocks != 0x6)
982 frame_bits++;
983 frame_bits++;
984 /* audio frame header */
985 if (s->num_blocks == 6)
986 frame_bits += 2;
987 frame_bits += 10;
988 /* exponent strategy */
989 if (s->use_frame_exp_strategy)
990 frame_bits += 5 * s->fbw_channels;
991 else
992 frame_bits += s->num_blocks * 2 * s->fbw_channels;
993 if (s->lfe_on)
994 frame_bits += s->num_blocks;
995 /* converter exponent strategy */
996 if (s->num_blks_code != 0x3)
997 frame_bits++;
998 else
999 frame_bits += s->fbw_channels * 5;
1000 /* snr offsets */
1001 frame_bits += 10;
1002 /* block start info */
1003 if (s->num_blocks != 1)
1004 frame_bits++;
1005 } else {
1006 frame_bits += 49;
1007 frame_bits += frame_bits_inc[s->channel_mode];
1008 }
1009
1010 /* audio blocks */
1011 for (blk = 0; blk < s->num_blocks; blk++) {
1012 if (!s->eac3) {
1013 /* block switch flags */
1014 frame_bits += s->fbw_channels;
1015
1016 /* dither flags */
1017 frame_bits += s->fbw_channels;
1018 }
1019
1020 /* dynamic range */
1021 frame_bits++;
1022
1023 /* spectral extension */
1024 if (s->eac3)
1025 frame_bits++;
1026
1027 /* coupling strategy exists: cplstre */
1028 if (!s->eac3)
1029 frame_bits++;
1030
1031 if (!s->eac3) {
1032 /* exponent strategy */
1033 frame_bits += 2 * s->fbw_channels;
1034 if (s->lfe_on)
1035 frame_bits++;
1036
1037 /* bit allocation params */
1038 frame_bits++;
1039 if (!blk)
1040 frame_bits += 2 + 2 + 2 + 2 + 3;
1041 }
1042
1043 /* snroffste for AC-3, convsnroffste for E-AC-3 */
1044 frame_bits++;
1045
1046 if (!s->eac3) {
1047 /* delta bit allocation */
1048 frame_bits++;
1049
1050 /* skipped data */
1051 frame_bits++;
1052 }
1053 }
1054
1055 /* auxiliary data */
1056 frame_bits++;
1057
1058 /* CRC */
1059 frame_bits += 1 + 16;
1060
1061 s->frame_bits_fixed = frame_bits;
1062 }
1063
1064
1065 /*
1066 * Initialize bit allocation.
1067 * Set default parameter codes and calculate parameter values.
1068 */
1069 static av_cold void bit_alloc_init(AC3EncodeContext *s)
1070 {
1071 int ch;
1072
1073 /* init default parameters */
1074 s->slow_decay_code = 2;
1075 s->fast_decay_code = 1;
1076 s->slow_gain_code = 1;
1077 s->db_per_bit_code = s->eac3 ? 2 : 3;
1078 s->floor_code = 7;
1079 for (ch = 0; ch <= s->channels; ch++)
1080 s->fast_gain_code[ch] = 4;
1081
1082 /* initial snr offset */
1083 s->coarse_snr_offset = 40;
1084
1085 /* compute real values */
1086 /* currently none of these values change during encoding, so we can just
1087 set them once at initialization */
1088 s->bit_alloc.slow_decay = ff_ac3_slow_decay_tab[s->slow_decay_code];
1089 s->bit_alloc.fast_decay = ff_ac3_fast_decay_tab[s->fast_decay_code];
1090 s->bit_alloc.slow_gain = ff_ac3_slow_gain_tab[s->slow_gain_code];
1091 s->bit_alloc.db_per_bit = ff_ac3_db_per_bit_tab[s->db_per_bit_code];
1092 s->bit_alloc.floor = ff_ac3_floor_tab[s->floor_code];
1093 s->bit_alloc.cpl_fast_leak = 0;
1094 s->bit_alloc.cpl_slow_leak = 0;
1095
1096 count_frame_bits_fixed(s);
1097 }
1098
1099
1100 /*
1101 * Count the bits used to encode the frame, minus exponents and mantissas.
1102 * Bits based on fixed parameters have already been counted, so now we just
1103 * have to add the bits based on parameters that change during encoding.
1104 */
1105 static void count_frame_bits(AC3EncodeContext *s)
1106 {
1107 AC3EncOptions *opt = &s->options;
1108 int blk, ch;
1109 int frame_bits = 0;
1110
1111 /* header */
1112 if (s->eac3) {
1113 if (opt->eac3_mixing_metadata) {
1114 if (s->channel_mode > AC3_CHMODE_STEREO)
1115 frame_bits += 2;
1116 if (s->has_center)
1117 frame_bits += 6;
1118 if (s->has_surround)
1119 frame_bits += 6;
1120 frame_bits += s->lfe_on;
1121 frame_bits += 1 + 1 + 2;
1122 if (s->channel_mode < AC3_CHMODE_STEREO)
1123 frame_bits++;
1124 frame_bits++;
1125 }
1126 if (opt->eac3_info_metadata) {
1127 frame_bits += 3 + 1 + 1;
1128 if (s->channel_mode == AC3_CHMODE_STEREO)
1129 frame_bits += 2 + 2;
1130 if (s->channel_mode >= AC3_CHMODE_2F2R)
1131 frame_bits += 2;
1132 frame_bits++;
1133 if (opt->audio_production_info)
1134 frame_bits += 5 + 2 + 1;
1135 frame_bits++;
1136 }
1137 /* coupling */
1138 if (s->channel_mode > AC3_CHMODE_MONO) {
1139 frame_bits++;
1140 for (blk = 1; blk < s->num_blocks; blk++) {
1141 AC3Block *block = &s->blocks[blk];
1142 frame_bits++;
1143 if (block->new_cpl_strategy)
1144 frame_bits++;
1145 }
1146 }
1147 /* coupling exponent strategy */
1148 if (s->cpl_on) {
1149 if (s->use_frame_exp_strategy) {
1150 frame_bits += 5;
1151 } else {
1152 for (blk = 0; blk < s->num_blocks; blk++)
1153 frame_bits += 2 * s->blocks[blk].cpl_in_use;
1154 }
1155 }
1156 } else {
1157 if (opt->audio_production_info)
1158 frame_bits += 7;
1159 if (s->bitstream_id == 6) {
1160 if (opt->extended_bsi_1)
1161 frame_bits += 14;
1162 if (opt->extended_bsi_2)
1163 frame_bits += 14;
1164 }
1165 }
1166
1167 /* audio blocks */
1168 for (blk = 0; blk < s->num_blocks; blk++) {
1169 AC3Block *block = &s->blocks[blk];
1170
1171 /* coupling strategy */
1172 if (block->new_cpl_strategy) {
1173 if (!s->eac3)
1174 frame_bits++;
1175 if (block->cpl_in_use) {
1176 if (s->eac3)
1177 frame_bits++;
1178 if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO)
1179 frame_bits += s->fbw_channels;
1180 if (s->channel_mode == AC3_CHMODE_STEREO)
1181 frame_bits++;
1182 frame_bits += 4 + 4;
1183 if (s->eac3)
1184 frame_bits++;
1185 else
1186 frame_bits += s->num_cpl_subbands - 1;
1187 }
1188 }
1189
1190 /* coupling coordinates */
1191 if (block->cpl_in_use) {
1192 for (ch = 1; ch <= s->fbw_channels; ch++) {
1193 if (block->channel_in_cpl[ch]) {
1194 if (!s->eac3 || block->new_cpl_coords[ch] != 2)
1195 frame_bits++;
1196 if (block->new_cpl_coords[ch]) {
1197 frame_bits += 2;
1198 frame_bits += (4 + 4) * s->num_cpl_bands;
1199 }
1200 }
1201 }
1202 }
1203
1204 /* stereo rematrixing */
1205 if (s->channel_mode == AC3_CHMODE_STEREO) {
1206 if (!s->eac3 || blk > 0)
1207 frame_bits++;
1208 if (s->blocks[blk].new_rematrixing_strategy)
1209 frame_bits += block->num_rematrixing_bands;
1210 }
1211
1212 /* bandwidth codes & gain range */
1213 for (ch = 1; ch <= s->fbw_channels; ch++) {
1214 if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1215 if (!block->channel_in_cpl[ch])
1216 frame_bits += 6;
1217 frame_bits += 2;
1218 }
1219 }
1220
1221 /* coupling exponent strategy */
1222 if (!s->eac3 && block->cpl_in_use)
1223 frame_bits += 2;
1224
1225 /* snr offsets and fast gain codes */
1226 if (!s->eac3) {
1227 if (block->new_snr_offsets)
1228 frame_bits += 6 + (s->channels + block->cpl_in_use) * (4 + 3);
1229 }
1230
1231 /* coupling leak info */
1232 if (block->cpl_in_use) {
1233 if (!s->eac3 || block->new_cpl_leak != 2)
1234 frame_bits++;
1235 if (block->new_cpl_leak)
1236 frame_bits += 3 + 3;
1237 }
1238 }
1239
1240 s->frame_bits = s->frame_bits_fixed + frame_bits;
1241 }
1242
1243
1244 /*
1245 * Calculate masking curve based on the final exponents.
1246 * Also calculate the power spectral densities to use in future calculations.
1247 */
1248 static void bit_alloc_masking(AC3EncodeContext *s)
1249 {
1250 int blk, ch;
1251
1252 for (blk = 0; blk < s->num_blocks; blk++) {
1253 AC3Block *block = &s->blocks[blk];
1254 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1255 /* We only need psd and mask for calculating bap.
1256 Since we currently do not calculate bap when exponent
1257 strategy is EXP_REUSE we do not need to calculate psd or mask. */
1258 if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1259 ff_ac3_bit_alloc_calc_psd(block->exp[ch], s->start_freq[ch],
1260 block->end_freq[ch], block->psd[ch],
1261 block->band_psd[ch]);
1262 ff_ac3_bit_alloc_calc_mask(&s->bit_alloc, block->band_psd[ch],
1263 s->start_freq[ch], block->end_freq[ch],
1264 ff_ac3_fast_gain_tab[s->fast_gain_code[ch]],
1265 ch == s->lfe_channel,
1266 DBA_NONE, 0, NULL, NULL, NULL,
1267 block->mask[ch]);
1268 }
1269 }
1270 }
1271 }
1272
1273
1274 /*
1275 * Ensure that bap for each block and channel point to the current bap_buffer.
1276 * They may have been switched during the bit allocation search.
1277 */
1278 static void reset_block_bap(AC3EncodeContext *s)
1279 {
1280 int blk, ch;
1281 uint8_t *ref_bap;
1282
1283 if (s->ref_bap[0][0] == s->bap_buffer && s->ref_bap_set)
1284 return;
1285
1286 ref_bap = s->bap_buffer;
1287 for (ch = 0; ch <= s->channels; ch++) {
1288 for (blk = 0; blk < s->num_blocks; blk++)
1289 s->ref_bap[ch][blk] = ref_bap + AC3_MAX_COEFS * s->exp_ref_block[ch][blk];
1290 ref_bap += AC3_MAX_COEFS * s->num_blocks;
1291 }
1292 s->ref_bap_set = 1;
1293 }
1294
1295
1296 /**
1297 * Initialize mantissa counts.
1298 * These are set so that they are padded to the next whole group size when bits
1299 * are counted in compute_mantissa_size.
1300 *
1301 * @param[in,out] mant_cnt running counts for each bap value for each block
1302 */
1303 static void count_mantissa_bits_init(uint16_t mant_cnt[AC3_MAX_BLOCKS][16])
1304 {
1305 int blk;
1306
1307 for (blk = 0; blk < AC3_MAX_BLOCKS; blk++) {
1308 memset(mant_cnt[blk], 0, sizeof(mant_cnt[blk]));
1309 mant_cnt[blk][1] = mant_cnt[blk][2] = 2;
1310 mant_cnt[blk][4] = 1;
1311 }
1312 }
1313
1314
1315 /**
1316 * Update mantissa bit counts for all blocks in 1 channel in a given bandwidth
1317 * range.
1318 *
1319 * @param s AC-3 encoder private context
1320 * @param ch channel index
1321 * @param[in,out] mant_cnt running counts for each bap value for each block
1322 * @param start starting coefficient bin
1323 * @param end ending coefficient bin
1324 */
1325 static void count_mantissa_bits_update_ch(AC3EncodeContext *s, int ch,
1326 uint16_t mant_cnt[AC3_MAX_BLOCKS][16],
1327 int start, int end)
1328 {
1329 int blk;
1330
1331 for (blk = 0; blk < s->num_blocks; blk++) {
1332 AC3Block *block = &s->blocks[blk];
1333 if (ch == CPL_CH && !block->cpl_in_use)
1334 continue;
1335 s->ac3dsp.update_bap_counts(mant_cnt[blk],
1336 s->ref_bap[ch][blk] + start,
1337 FFMIN(end, block->end_freq[ch]) - start);
1338 }
1339 }
1340
1341
1342 /*
1343 * Count the number of mantissa bits in the frame based on the bap values.
1344 */
1345 static int count_mantissa_bits(AC3EncodeContext *s)
1346 {
1347 int ch, max_end_freq;
1348 LOCAL_ALIGNED_16(uint16_t, mant_cnt, [AC3_MAX_BLOCKS], [16]);
1349
1350 count_mantissa_bits_init(mant_cnt);
1351
1352 max_end_freq = s->bandwidth_code * 3 + 73;
1353 for (ch = !s->cpl_enabled; ch <= s->channels; ch++)
1354 count_mantissa_bits_update_ch(s, ch, mant_cnt, s->start_freq[ch],
1355 max_end_freq);
1356
1357 return s->ac3dsp.compute_mantissa_size(mant_cnt);
1358 }
1359
1360
1361 /**
1362 * Run the bit allocation with a given SNR offset.
1363 * This calculates the bit allocation pointers that will be used to determine
1364 * the quantization of each mantissa.
1365 *
1366 * @param s AC-3 encoder private context
1367 * @param snr_offset SNR offset, 0 to 1023
1368 * @return the number of bits needed for mantissas if the given SNR offset is
1369 * is used.
1370 */
1371 static int bit_alloc(AC3EncodeContext *s, int snr_offset)
1372 {
1373 int blk, ch;
1374
1375 snr_offset = (snr_offset - 240) * 4;
1376
1377 reset_block_bap(s);
1378 for (blk = 0; blk < s->num_blocks; blk++) {
1379 AC3Block *block = &s->blocks[blk];
1380
1381 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1382 /* Currently the only bit allocation parameters which vary across
1383 blocks within a frame are the exponent values. We can take
1384 advantage of that by reusing the bit allocation pointers
1385 whenever we reuse exponents. */
1386 if (s->exp_strategy[ch][blk] != EXP_REUSE) {
1387 s->ac3dsp.bit_alloc_calc_bap(block->mask[ch], block->psd[ch],
1388 s->start_freq[ch], block->end_freq[ch],
1389 snr_offset, s->bit_alloc.floor,
1390 ff_ac3_bap_tab, s->ref_bap[ch][blk]);
1391 }
1392 }
1393 }
1394 return count_mantissa_bits(s);
1395 }
1396
1397
1398 /*
1399 * Constant bitrate bit allocation search.
1400 * Find the largest SNR offset that will allow data to fit in the frame.
1401 */
1402 static int cbr_bit_allocation(AC3EncodeContext *s)
1403 {
1404 int ch;
1405 int bits_left;
1406 int snr_offset, snr_incr;
1407
1408 bits_left = 8 * s->frame_size - (s->frame_bits + s->exponent_bits);
1409 if (bits_left < 0)
1410 return AVERROR(EINVAL);
1411
1412 snr_offset = s->coarse_snr_offset << 4;
1413
1414 /* if previous frame SNR offset was 1023, check if current frame can also
1415 use SNR offset of 1023. if so, skip the search. */
1416 if ((snr_offset | s->fine_snr_offset[1]) == 1023) {
1417 if (bit_alloc(s, 1023) <= bits_left)
1418 return 0;
1419 }
1420
1421 while (snr_offset >= 0 &&
1422 bit_alloc(s, snr_offset) > bits_left) {
1423 snr_offset -= 64;
1424 }
1425 if (snr_offset < 0)
1426 return AVERROR(EINVAL);
1427
1428 FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1429 for (snr_incr = 64; snr_incr > 0; snr_incr >>= 2) {
1430 while (snr_offset + snr_incr <= 1023 &&
1431 bit_alloc(s, snr_offset + snr_incr) <= bits_left) {
1432 snr_offset += snr_incr;
1433 FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1434 }
1435 }
1436 FFSWAP(uint8_t *, s->bap_buffer, s->bap1_buffer);
1437 reset_block_bap(s);
1438
1439 s->coarse_snr_offset = snr_offset >> 4;
1440 for (ch = !s->cpl_on; ch <= s->channels; ch++)
1441 s->fine_snr_offset[ch] = snr_offset & 0xF;
1442
1443 return 0;
1444 }
1445
1446
1447 /*
1448 * Perform bit allocation search.
1449 * Finds the SNR offset value that maximizes quality and fits in the specified
1450 * frame size. Output is the SNR offset and a set of bit allocation pointers
1451 * used to quantize the mantissas.
1452 */
1453 static int ac3_compute_bit_allocation(AC3EncodeContext *s)
1454 {
1455 count_frame_bits(s);
1456
1457 s->exponent_bits = count_exponent_bits(s);
1458
1459 bit_alloc_masking(s);
1460
1461 return cbr_bit_allocation(s);
1462 }
1463
1464
1465 /**
1466 * Symmetric quantization on 'levels' levels.
1467 *
1468 * @param c unquantized coefficient
1469 * @param e exponent
1470 * @param levels number of quantization levels
1471 * @return quantized coefficient
1472 */
1473 static inline int sym_quant(int c, int e, int levels)
1474 {
1475 int v = (((levels * c) >> (24 - e)) + levels) >> 1;
1476 av_assert2(v >= 0 && v < levels);
1477 return v;
1478 }
1479
1480
1481 /**
1482 * Asymmetric quantization on 2^qbits levels.
1483 *
1484 * @param c unquantized coefficient
1485 * @param e exponent
1486 * @param qbits number of quantization bits
1487 * @return quantized coefficient
1488 */
1489 static inline int asym_quant(int c, int e, int qbits)
1490 {
1491 int m;
1492
1493 c = (((c * (1<<e)) >> (24 - qbits)) + 1) >> 1;
1494 m = (1 << (qbits-1));
1495 if (c >= m)
1496 c = m - 1;
1497 av_assert2(c >= -m);
1498 return c;
1499 }
1500
1501
1502 /**
1503 * Quantize a set of mantissas for a single channel in a single block.
1504 *
1505 * @param s Mantissa count context
1506 * @param fixed_coef unquantized fixed-point coefficients
1507 * @param exp exponents
1508 * @param bap bit allocation pointer indices
1509 * @param[out] qmant quantized coefficients
1510 * @param start_freq starting coefficient bin
1511 * @param end_freq ending coefficient bin
1512 */
1513 static void quantize_mantissas_blk_ch(AC3Mant *s, int32_t *fixed_coef,
1514 uint8_t *exp, uint8_t *bap,
1515 int16_t *qmant, int start_freq,
1516 int end_freq)
1517 {
1518 int i;
1519
1520 for (i = start_freq; i < end_freq; i++) {
1521 int c = fixed_coef[i];
1522 int e = exp[i];
1523 int v = bap[i];
1524 switch (v) {
1525 case 0:
1526 break;
1527 case 1:
1528 v = sym_quant(c, e, 3);
1529 switch (s->mant1_cnt) {
1530 case 0:
1531 s->qmant1_ptr = &qmant[i];
1532 v = 9 * v;
1533 s->mant1_cnt = 1;
1534 break;
1535 case 1:
1536 *s->qmant1_ptr += 3 * v;
1537 s->mant1_cnt = 2;
1538 v = 128;
1539 break;
1540 default:
1541 *s->qmant1_ptr += v;
1542 s->mant1_cnt = 0;
1543 v = 128;
1544 break;
1545 }
1546 break;
1547 case 2:
1548 v = sym_quant(c, e, 5);
1549 switch (s->mant2_cnt) {
1550 case 0:
1551 s->qmant2_ptr = &qmant[i];
1552 v = 25 * v;
1553 s->mant2_cnt = 1;
1554 break;
1555 case 1:
1556 *s->qmant2_ptr += 5 * v;
1557 s->mant2_cnt = 2;
1558 v = 128;
1559 break;
1560 default:
1561 *s->qmant2_ptr += v;
1562 s->mant2_cnt = 0;
1563 v = 128;
1564 break;
1565 }
1566 break;
1567 case 3:
1568 v = sym_quant(c, e, 7);
1569 break;
1570 case 4:
1571 v = sym_quant(c, e, 11);
1572 switch (s->mant4_cnt) {
1573 case 0:
1574 s->qmant4_ptr = &qmant[i];
1575 v = 11 * v;
1576 s->mant4_cnt = 1;
1577 break;
1578 default:
1579 *s->qmant4_ptr += v;
1580 s->mant4_cnt = 0;
1581 v = 128;
1582 break;
1583 }
1584 break;
1585 case 5:
1586 v = sym_quant(c, e, 15);
1587 break;
1588 case 14:
1589 v = asym_quant(c, e, 14);
1590 break;
1591 case 15:
1592 v = asym_quant(c, e, 16);
1593 break;
1594 default:
1595 v = asym_quant(c, e, v - 1);
1596 break;
1597 }
1598 qmant[i] = v;
1599 }
1600 }
1601
1602
1603 /**
1604 * Quantize mantissas using coefficients, exponents, and bit allocation pointers.
1605 *
1606 * @param s AC-3 encoder private context
1607 */
1608 static void ac3_quantize_mantissas(AC3EncodeContext *s)
1609 {
1610 int blk, ch, ch0=0, got_cpl;
1611
1612 for (blk = 0; blk < s->num_blocks; blk++) {
1613 AC3Block *block = &s->blocks[blk];
1614 AC3Mant m = { 0 };
1615
1616 got_cpl = !block->cpl_in_use;
1617 for (ch = 1; ch <= s->channels; ch++) {
1618 if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1619 ch0 = ch - 1;
1620 ch = CPL_CH;
1621 got_cpl = 1;
1622 }
1623 quantize_mantissas_blk_ch(&m, block->fixed_coef[ch],
1624 s->blocks[s->exp_ref_block[ch][blk]].exp[ch],
1625 s->ref_bap[ch][blk], block->qmant[ch],
1626 s->start_freq[ch], block->end_freq[ch]);
1627 if (ch == CPL_CH)
1628 ch = ch0;
1629 }
1630 }
1631 }
1632
1633
1634 /*
1635 * Write the AC-3 frame header to the output bitstream.
1636 */
1637 static void ac3_output_frame_header(AC3EncodeContext *s, PutBitContext *pb)
1638 {
1639 AC3EncOptions *opt = &s->options;
1640
1641 put_bits(pb, 16, 0x0b77); /* frame header */
1642 put_bits(pb, 16, 0); /* crc1: will be filled later */
1643 put_bits(pb, 2, s->bit_alloc.sr_code);
1644 put_bits(pb, 6, s->frame_size_code + (s->frame_size - s->frame_size_min) / 2);
1645 put_bits(pb, 5, s->bitstream_id);
1646 put_bits(pb, 3, s->bitstream_mode);
1647 put_bits(pb, 3, s->channel_mode);
1648 if ((s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO)
1649 put_bits(pb, 2, s->center_mix_level);
1650 if (s->channel_mode & 0x04)
1651 put_bits(pb, 2, s->surround_mix_level);
1652 if (s->channel_mode == AC3_CHMODE_STEREO)
1653 put_bits(pb, 2, opt->dolby_surround_mode);
1654 put_bits(pb, 1, s->lfe_on); /* LFE */
1655 put_bits(pb, 5, -opt->dialogue_level);
1656 put_bits(pb, 1, 0); /* no compression control word */
1657 put_bits(pb, 1, 0); /* no lang code */
1658 put_bits(pb, 1, opt->audio_production_info);
1659 if (opt->audio_production_info) {
1660 put_bits(pb, 5, opt->mixing_level - 80);
1661 put_bits(pb, 2, opt->room_type);
1662 }
1663 put_bits(pb, 1, opt->copyright);
1664 put_bits(pb, 1, opt->original);
1665 if (s->bitstream_id == 6) {
1666 /* alternate bit stream syntax */
1667 put_bits(pb, 1, opt->extended_bsi_1);
1668 if (opt->extended_bsi_1) {
1669 put_bits(pb, 2, opt->preferred_stereo_downmix);
1670 put_bits(pb, 3, s->ltrt_center_mix_level);
1671 put_bits(pb, 3, s->ltrt_surround_mix_level);
1672 put_bits(pb, 3, s->loro_center_mix_level);
1673 put_bits(pb, 3, s->loro_surround_mix_level);
1674 }
1675 put_bits(pb, 1, opt->extended_bsi_2);
1676 if (opt->extended_bsi_2) {
1677 put_bits(pb, 2, opt->dolby_surround_ex_mode);
1678 put_bits(pb, 2, opt->dolby_headphone_mode);
1679 put_bits(pb, 1, opt->ad_converter_type);
1680 put_bits(pb, 9, 0); /* xbsi2 and encinfo : reserved */
1681 }
1682 } else {
1683 put_bits(pb, 1, 0); /* no time code 1 */
1684 put_bits(pb, 1, 0); /* no time code 2 */
1685 }
1686 put_bits(pb, 1, 0); /* no additional bit stream info */
1687 }
1688
1689
1690 /*
1691 * Write one audio block to the output bitstream.
1692 */
1693 static void output_audio_block(AC3EncodeContext *s, PutBitContext *pb, int blk)
1694 {
1695 int ch, i, baie, bnd, got_cpl, av_uninit(ch0);
1696 AC3Block *block = &s->blocks[blk];
1697
1698 /* block switching */
1699 if (!s->eac3) {
1700 for (ch = 0; ch < s->fbw_channels; ch++)
1701 put_bits(pb, 1, 0);
1702 }
1703
1704 /* dither flags */
1705 if (!s->eac3) {
1706 for (ch = 0; ch < s->fbw_channels; ch++)
1707 put_bits(pb, 1, 1);
1708 }
1709
1710 /* dynamic range codes */
1711 put_bits(pb, 1, 0);
1712
1713 /* spectral extension */
1714 if (s->eac3)
1715 put_bits(pb, 1, 0);
1716
1717 /* channel coupling */
1718 if (!s->eac3)
1719 put_bits(pb, 1, block->new_cpl_strategy);
1720 if (block->new_cpl_strategy) {
1721 if (!s->eac3)
1722 put_bits(pb, 1, block->cpl_in_use);
1723 if (block->cpl_in_use) {
1724 int start_sub, end_sub;
1725 if (s->eac3)
1726 put_bits(pb, 1, 0); /* enhanced coupling */
1727 if (!s->eac3 || s->channel_mode != AC3_CHMODE_STEREO) {
1728 for (ch = 1; ch <= s->fbw_channels; ch++)
1729 put_bits(pb, 1, block->channel_in_cpl[ch]);
1730 }
1731 if (s->channel_mode == AC3_CHMODE_STEREO)
1732 put_bits(pb, 1, 0); /* phase flags in use */
1733 start_sub = (s->start_freq[CPL_CH] - 37) / 12;
1734 end_sub = (s->cpl_end_freq - 37) / 12;
1735 put_bits(pb, 4, start_sub);
1736 put_bits(pb, 4, end_sub - 3);
1737 /* coupling band structure */
1738 if (s->eac3) {
1739 put_bits(pb, 1, 0); /* use default */
1740 } else {
1741 for (bnd = start_sub+1; bnd < end_sub; bnd++)
1742 put_bits(pb, 1, ff_eac3_default_cpl_band_struct[bnd]);
1743 }
1744 }
1745 }
1746
1747 /* coupling coordinates */
1748 if (block->cpl_in_use) {
1749 for (ch = 1; ch <= s->fbw_channels; ch++) {
1750 if (block->channel_in_cpl[ch]) {
1751 if (!s->eac3 || block->new_cpl_coords[ch] != 2)
1752 put_bits(pb, 1, block->new_cpl_coords[ch]);
1753 if (block->new_cpl_coords[ch]) {
1754 put_bits(pb, 2, block->cpl_master_exp[ch]);
1755 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
1756 put_bits(pb, 4, block->cpl_coord_exp [ch][bnd]);
1757 put_bits(pb, 4, block->cpl_coord_mant[ch][bnd]);
1758 }
1759 }
1760 }
1761 }
1762 }
1763
1764 /* stereo rematrixing */
1765 if (s->channel_mode == AC3_CHMODE_STEREO) {
1766 if (!s->eac3 || blk > 0)
1767 put_bits(pb, 1, block->new_rematrixing_strategy);
1768 if (block->new_rematrixing_strategy) {
1769 /* rematrixing flags */
1770 for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++)
1771 put_bits(pb, 1, block->rematrixing_flags[bnd]);
1772 }
1773 }
1774
1775 /* exponent strategy */
1776 if (!s->eac3) {
1777 for (ch = !block->cpl_in_use; ch <= s->fbw_channels; ch++)
1778 put_bits(pb, 2, s->exp_strategy[ch][blk]);
1779 if (s->lfe_on)
1780 put_bits(pb, 1, s->exp_strategy[s->lfe_channel][blk]);
1781 }
1782
1783 /* bandwidth */
1784 for (ch = 1; ch <= s->fbw_channels; ch++) {
1785 if (s->exp_strategy[ch][blk] != EXP_REUSE && !block->channel_in_cpl[ch])
1786 put_bits(pb, 6, s->bandwidth_code);
1787 }
1788
1789 /* exponents */
1790 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1791 int nb_groups;
1792 int cpl = (ch == CPL_CH);
1793
1794 if (s->exp_strategy[ch][blk] == EXP_REUSE)
1795 continue;
1796
1797 /* DC exponent */
1798 put_bits(pb, 4, block->grouped_exp[ch][0] >> cpl);
1799
1800 /* exponent groups */
1801 nb_groups = exponent_group_tab[cpl][s->exp_strategy[ch][blk]-1][block->end_freq[ch]-s->start_freq[ch]];
1802 for (i = 1; i <= nb_groups; i++)
1803 put_bits(pb, 7, block->grouped_exp[ch][i]);
1804
1805 /* gain range info */
1806 if (ch != s->lfe_channel && !cpl)
1807 put_bits(pb, 2, 0);
1808 }
1809
1810 /* bit allocation info */
1811 if (!s->eac3) {
1812 baie = (blk == 0);
1813 put_bits(pb, 1, baie);
1814 if (baie) {
1815 put_bits(pb, 2, s->slow_decay_code);
1816 put_bits(pb, 2, s->fast_decay_code);
1817 put_bits(pb, 2, s->slow_gain_code);
1818 put_bits(pb, 2, s->db_per_bit_code);
1819 put_bits(pb, 3, s->floor_code);
1820 }
1821 }
1822
1823 /* snr offset */
1824 if (!s->eac3) {
1825 put_bits(pb, 1, block->new_snr_offsets);
1826 if (block->new_snr_offsets) {
1827 put_bits(pb, 6, s->coarse_snr_offset);
1828 for (ch = !block->cpl_in_use; ch <= s->channels; ch++) {
1829 put_bits(pb, 4, s->fine_snr_offset[ch]);
1830 put_bits(pb, 3, s->fast_gain_code[ch]);
1831 }
1832 }
1833 } else {
1834 put_bits(pb, 1, 0); /* no converter snr offset */
1835 }
1836
1837 /* coupling leak */
1838 if (block->cpl_in_use) {
1839 if (!s->eac3 || block->new_cpl_leak != 2)
1840 put_bits(pb, 1, block->new_cpl_leak);
1841 if (block->new_cpl_leak) {
1842 put_bits(pb, 3, s->bit_alloc.cpl_fast_leak);
1843 put_bits(pb, 3, s->bit_alloc.cpl_slow_leak);
1844 }
1845 }
1846
1847 if (!s->eac3) {
1848 put_bits(pb, 1, 0); /* no delta bit allocation */
1849 put_bits(pb, 1, 0); /* no data to skip */
1850 }
1851
1852 /* mantissas */
1853 got_cpl = !block->cpl_in_use;
1854 for (ch = 1; ch <= s->channels; ch++) {
1855 int b, q;
1856
1857 if (!got_cpl && ch > 1 && block->channel_in_cpl[ch-1]) {
1858 ch0 = ch - 1;
1859 ch = CPL_CH;
1860 got_cpl = 1;
1861 }
1862 for (i = s->start_freq[ch]; i < block->end_freq[ch]; i++) {
1863 q = block->qmant[ch][i];
1864 b = s->ref_bap[ch][blk][i];
1865 switch (b) {
1866 case 0: break;
1867 case 1: if (q != 128) put_bits (pb, 5, q); break;
1868 case 2: if (q != 128) put_bits (pb, 7, q); break;
1869 case 3: put_sbits(pb, 3, q); break;
1870 case 4: if (q != 128) put_bits (pb, 7, q); break;
1871 case 14: put_sbits(pb, 14, q); break;
1872 case 15: put_sbits(pb, 16, q); break;
1873 default: put_sbits(pb, b-1, q); break;
1874 }
1875 }
1876 if (ch == CPL_CH)
1877 ch = ch0;
1878 }
1879 }
1880
1881
1882 /** CRC-16 Polynomial */
1883 #define CRC16_POLY ((1 << 0) | (1 << 2) | (1 << 15) | (1 << 16))
1884
1885
1886 static unsigned int mul_poly(unsigned int a, unsigned int b, unsigned int poly)
1887 {
1888 unsigned int c;
1889
1890 c = 0;
1891 while (a) {
1892 if (a & 1)
1893 c ^= b;
1894 a = a >> 1;
1895 b = b << 1;
1896 if (b & (1 << 16))
1897 b ^= poly;
1898 }
1899 return c;
1900 }
1901
1902
1903 static unsigned int pow_poly(unsigned int a, unsigned int n, unsigned int poly)
1904 {
1905 unsigned int r;
1906 r = 1;
1907 while (n) {
1908 if (n & 1)
1909 r = mul_poly(r, a, poly);
1910 a = mul_poly(a, a, poly);
1911 n >>= 1;
1912 }
1913 return r;
1914 }
1915
1916
1917 /*
1918 * Fill the end of the frame with 0's and compute the two CRCs.
1919 */
1920 static void output_frame_end(AC3EncodeContext *s, PutBitContext *pb)
1921 {
1922 const AVCRC *crc_ctx = av_crc_get_table(AV_CRC_16_ANSI);
1923 int frame_size_58, pad_bytes, crc1, crc2, crc_inv;
1924 uint8_t *frame;
1925
1926 frame_size_58 = ((s->frame_size >> 2) + (s->frame_size >> 4)) << 1;
1927
1928 /* pad the remainder of the frame with zeros */
1929 av_assert2(s->frame_size * 8 - put_bits_count(pb) >= 18);
1930 flush_put_bits(pb);
1931 frame = pb->buf;
1932 pad_bytes = s->frame_size - (put_bits_ptr(pb) - frame) - 2;
1933 av_assert2(pad_bytes >= 0);
1934 if (pad_bytes > 0)
1935 memset(put_bits_ptr(pb), 0, pad_bytes);
1936
1937 if (s->eac3) {
1938 /* compute crc2 */
1939 crc2 = av_crc(crc_ctx, 0, frame + 2, s->frame_size - 4);
1940 } else {
1941 /* compute crc1 */
1942 /* this is not so easy because it is at the beginning of the data... */
1943 crc1 = av_bswap16(av_crc(crc_ctx, 0, frame + 4, frame_size_58 - 4));
1944 crc_inv = s->crc_inv[s->frame_size > s->frame_size_min];
1945 crc1 = mul_poly(crc_inv, crc1, CRC16_POLY);
1946 AV_WB16(frame + 2, crc1);
1947
1948 /* compute crc2 */
1949 crc2 = av_crc(crc_ctx, 0, frame + frame_size_58,
1950 s->frame_size - frame_size_58 - 2);
1951 }
1952 crc2 = av_bswap16(crc2);
1953 /* ensure crc2 does not match sync word by flipping crcrsv bit if needed */
1954 if (crc2 == 0x0B77) {
1955 /* The CRC generator polynomial is x^16 + x^15 + x^2 + 1,
1956 * so xor'ing with 0x18005 does not affect the CRC. */
1957 frame[s->frame_size - 3] ^= 0x1;
1958 crc2 ^= 0x8005;
1959 }
1960 AV_WB16(frame + s->frame_size - 2, crc2);
1961 }
1962
1963
1964 /**
1965 * Write the frame to the output bitstream.
1966 *
1967 * @param s AC-3 encoder private context
1968 * @param frame output data buffer
1969 */
1970 static void ac3_output_frame(AC3EncodeContext *s, unsigned char *frame)
1971 {
1972 PutBitContext pb;
1973 int blk;
1974
1975 init_put_bits(&pb, frame, s->frame_size);
1976
1977 s->output_frame_header(s, &pb);
1978
1979 for (blk = 0; blk < s->num_blocks; blk++)
1980 output_audio_block(s, &pb, blk);
1981
1982 output_frame_end(s, &pb);
1983 }
1984
1985 int ff_ac3_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
1986 const AVFrame *frame, int *got_packet_ptr)
1987 {
1988 AC3EncodeContext *const s = avctx->priv_data;
1989 int ret;
1990
1991 if (s->options.allow_per_frame_metadata) {
1992 ret = ac3_validate_metadata(s);
1993 if (ret)
1994 return ret;
1995 }
1996
1997 if (s->bit_alloc.sr_code == 1 || s->eac3)
1998 ac3_adjust_frame_size(s);
1999
2000 s->encode_frame(s, frame->extended_data);
2001
2002 ac3_apply_rematrixing(s);
2003
2004 ac3_process_exponents(s);
2005
2006 ret = ac3_compute_bit_allocation(s);
2007 if (ret) {
2008 av_log(avctx, AV_LOG_ERROR, "Bit allocation failed. Try increasing the bitrate.\n");
2009 return ret;
2010 }
2011
2012 ac3_group_exponents(s);
2013
2014 ac3_quantize_mantissas(s);
2015
2016 ret = ff_get_encode_buffer(avctx, avpkt, s->frame_size, 0);
2017 if (ret < 0)
2018 return ret;
2019 ac3_output_frame(s, avpkt->data);
2020
2021 if (frame->pts != AV_NOPTS_VALUE)
2022 avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->initial_padding);
2023
2024 *got_packet_ptr = 1;
2025 return 0;
2026 }
2027
2028 static void dprint_options(AC3EncodeContext *s)
2029 {
2030 #ifdef DEBUG
2031 AVCodecContext *avctx = s->avctx;
2032 AC3EncOptions *opt = &s->options;
2033 const char *msg;
2034 char strbuf[32];
2035
2036 switch (s->bitstream_id) {
2037 case 6: msg = "AC-3 (alt syntax)"; break;
2038 case 8: msg = "AC-3 (standard)"; break;
2039 case 16: msg = "E-AC-3 (enhanced)"; break;
2040 default: msg = "ERROR";
2041 }
2042 ff_dlog(avctx, "bitstream_id: %s (%d)\n", msg, s->bitstream_id);
2043 ff_dlog(avctx, "sample_fmt: %s\n", av_get_sample_fmt_name(avctx->sample_fmt));
2044 av_channel_layout_describe(&avctx->ch_layout, strbuf, sizeof(strbuf));
2045 ff_dlog(avctx, "channel_layout: %s\n", strbuf);
2046 ff_dlog(avctx, "sample_rate: %d\n", s->sample_rate);
2047 ff_dlog(avctx, "bit_rate: %d\n", s->bit_rate);
2048 ff_dlog(avctx, "blocks/frame: %d (code=%d)\n", s->num_blocks, s->num_blks_code);
2049 if (s->cutoff)
2050 ff_dlog(avctx, "cutoff: %d\n", s->cutoff);
2051
2052 ff_dlog(avctx, "per_frame_metadata: %s\n",
2053 opt->allow_per_frame_metadata?"on":"off");
2054 if (s->has_center)
2055 ff_dlog(avctx, "center_mixlev: %0.3f (%d)\n", opt->center_mix_level,
2056 s->center_mix_level);
2057 else
2058 ff_dlog(avctx, "center_mixlev: {not written}\n");
2059 if (s->has_surround)
2060 ff_dlog(avctx, "surround_mixlev: %0.3f (%d)\n", opt->surround_mix_level,
2061 s->surround_mix_level);
2062 else
2063 ff_dlog(avctx, "surround_mixlev: {not written}\n");
2064 if (opt->audio_production_info) {
2065 ff_dlog(avctx, "mixing_level: %ddB\n", opt->mixing_level);
2066 switch (opt->room_type) {
2067 case AC3ENC_OPT_NOT_INDICATED: msg = "notindicated"; break;
2068 case AC3ENC_OPT_LARGE_ROOM: msg = "large"; break;
2069 case AC3ENC_OPT_SMALL_ROOM: msg = "small"; break;
2070 default:
2071 snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->room_type);
2072 msg = strbuf;
2073 }
2074 ff_dlog(avctx, "room_type: %s\n", msg);
2075 } else {
2076 ff_dlog(avctx, "mixing_level: {not written}\n");
2077 ff_dlog(avctx, "room_type: {not written}\n");
2078 }
2079 ff_dlog(avctx, "copyright: %s\n", opt->copyright?"on":"off");
2080 ff_dlog(avctx, "dialnorm: %ddB\n", opt->dialogue_level);
2081 if (s->channel_mode == AC3_CHMODE_STEREO) {
2082 switch (opt->dolby_surround_mode) {
2083 case AC3ENC_OPT_NOT_INDICATED: msg = "notindicated"; break;
2084 case AC3ENC_OPT_MODE_ON: msg = "on"; break;
2085 case AC3ENC_OPT_MODE_OFF: msg = "off"; break;
2086 default:
2087 snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->dolby_surround_mode);
2088 msg = strbuf;
2089 }
2090 ff_dlog(avctx, "dsur_mode: %s\n", msg);
2091 } else {
2092 ff_dlog(avctx, "dsur_mode: {not written}\n");
2093 }
2094 ff_dlog(avctx, "original: %s\n", opt->original?"on":"off");
2095
2096 if (s->bitstream_id == 6) {
2097 if (opt->extended_bsi_1) {
2098 switch (opt->preferred_stereo_downmix) {
2099 case AC3ENC_OPT_NOT_INDICATED: msg = "notindicated"; break;
2100 case AC3ENC_OPT_DOWNMIX_LTRT: msg = "ltrt"; break;
2101 case AC3ENC_OPT_DOWNMIX_LORO: msg = "loro"; break;
2102 default:
2103 snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->preferred_stereo_downmix);
2104 msg = strbuf;
2105 }
2106 ff_dlog(avctx, "dmix_mode: %s\n", msg);
2107 ff_dlog(avctx, "ltrt_cmixlev: %0.3f (%d)\n",
2108 opt->ltrt_center_mix_level, s->ltrt_center_mix_level);
2109 ff_dlog(avctx, "ltrt_surmixlev: %0.3f (%d)\n",
2110 opt->ltrt_surround_mix_level, s->ltrt_surround_mix_level);
2111 ff_dlog(avctx, "loro_cmixlev: %0.3f (%d)\n",
2112 opt->loro_center_mix_level, s->loro_center_mix_level);
2113 ff_dlog(avctx, "loro_surmixlev: %0.3f (%d)\n",
2114 opt->loro_surround_mix_level, s->loro_surround_mix_level);
2115 } else {
2116 ff_dlog(avctx, "extended bitstream info 1: {not written}\n");
2117 }
2118 if (opt->extended_bsi_2) {
2119 switch (opt->dolby_surround_ex_mode) {
2120 case AC3ENC_OPT_NOT_INDICATED: msg = "notindicated"; break;
2121 case AC3ENC_OPT_MODE_ON: msg = "on"; break;
2122 case AC3ENC_OPT_MODE_OFF: msg = "off"; break;
2123 default:
2124 snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->dolby_surround_ex_mode);
2125 msg = strbuf;
2126 }
2127 ff_dlog(avctx, "dsurex_mode: %s\n", msg);
2128 switch (opt->dolby_headphone_mode) {
2129 case AC3ENC_OPT_NOT_INDICATED: msg = "notindicated"; break;
2130 case AC3ENC_OPT_MODE_ON: msg = "on"; break;
2131 case AC3ENC_OPT_MODE_OFF: msg = "off"; break;
2132 default:
2133 snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->dolby_headphone_mode);
2134 msg = strbuf;
2135 }
2136 ff_dlog(avctx, "dheadphone_mode: %s\n", msg);
2137
2138 switch (opt->ad_converter_type) {
2139 case AC3ENC_OPT_ADCONV_STANDARD: msg = "standard"; break;
2140 case AC3ENC_OPT_ADCONV_HDCD: msg = "hdcd"; break;
2141 default:
2142 snprintf(strbuf, sizeof(strbuf), "ERROR (%d)", opt->ad_converter_type);
2143 msg = strbuf;
2144 }
2145 ff_dlog(avctx, "ad_conv_type: %s\n", msg);
2146 } else {
2147 ff_dlog(avctx, "extended bitstream info 2: {not written}\n");
2148 }
2149 }
2150 #endif
2151 }
2152
2153 /**
2154 * Finalize encoding and free any memory allocated by the encoder.
2155 *
2156 * @param avctx Codec context
2157 */
2158 av_cold int ff_ac3_encode_close(AVCodecContext *avctx)
2159 {
2160 AC3EncodeContext *s = avctx->priv_data;
2161
2162 for (int ch = 0; ch < s->channels; ch++)
2163 av_freep(&s->planar_samples[ch]);
2164 av_freep(&s->bap_buffer);
2165 av_freep(&s->bap1_buffer);
2166 av_freep(&s->mdct_coef_buffer);
2167 av_freep(&s->fixed_coef_buffer);
2168 av_freep(&s->exp_buffer);
2169 av_freep(&s->grouped_exp_buffer);
2170 av_freep(&s->psd_buffer);
2171 av_freep(&s->band_psd_buffer);
2172 av_freep(&s->mask_buffer);
2173 av_freep(&s->qmant_buffer);
2174 av_freep(&s->cpl_coord_buffer);
2175 av_freep(&s->fdsp);
2176
2177 av_tx_uninit(&s->tx);
2178
2179 return 0;
2180 }
2181
2182
2183 /*
2184 * Set channel information during initialization.
2185 */
2186 static av_cold void set_channel_info(AVCodecContext *avctx)
2187 {
2188 AC3EncodeContext *s = avctx->priv_data;
2189 uint64_t mask = av_channel_layout_subset(&avctx->ch_layout, ~(uint64_t)0);
2190 int channels = avctx->ch_layout.nb_channels;
2191
2192 s->lfe_on = !!(mask & AV_CH_LOW_FREQUENCY);
2193 s->channels = channels;
2194 s->fbw_channels = channels - s->lfe_on;
2195 s->lfe_channel = s->lfe_on ? s->fbw_channels + 1 : -1;
2196
2197 switch (mask & ~AV_CH_LOW_FREQUENCY) {
2198 case AV_CH_LAYOUT_MONO: s->channel_mode = AC3_CHMODE_MONO; break;
2199 case AV_CH_LAYOUT_STEREO: s->channel_mode = AC3_CHMODE_STEREO; break;
2200 case AV_CH_LAYOUT_SURROUND: s->channel_mode = AC3_CHMODE_3F; break;
2201 case AV_CH_LAYOUT_2_1: s->channel_mode = AC3_CHMODE_2F1R; break;
2202 case AV_CH_LAYOUT_4POINT0: s->channel_mode = AC3_CHMODE_3F1R; break;
2203 case AV_CH_LAYOUT_QUAD:
2204 case AV_CH_LAYOUT_2_2: s->channel_mode = AC3_CHMODE_2F2R; break;
2205 case AV_CH_LAYOUT_5POINT0:
2206 case AV_CH_LAYOUT_5POINT0_BACK: s->channel_mode = AC3_CHMODE_3F2R; break;
2207 }
2208 s->has_center = (s->channel_mode & 0x01) && s->channel_mode != AC3_CHMODE_MONO;
2209 s->has_surround = s->channel_mode & 0x04;
2210
2211 s->channel_map = ac3_enc_channel_map[s->channel_mode][s->lfe_on];
2212 }
2213
2214
2215 static av_cold int validate_options(AC3EncodeContext *s)
2216 {
2217 AVCodecContext *avctx = s->avctx;
2218 int ret;
2219
2220 set_channel_info(avctx);
2221
2222 for (int i = 0;; i++) {
2223 if (ff_ac3_sample_rate_tab[i] == avctx->sample_rate) {
2224 s->bit_alloc.sr_code = i;
2225 break;
2226 }
2227 av_assert1(ff_ac3_sample_rate_tab[i] != 0);
2228 }
2229 s->sample_rate = avctx->sample_rate;
2230 s->bitstream_id = s->eac3 ? 16 : 8;
2231
2232 /* select a default bit rate if not set by the user */
2233 if (!avctx->bit_rate) {
2234 switch (s->fbw_channels) {
2235 case 1: avctx->bit_rate = 96000; break;
2236 case 2: avctx->bit_rate = 192000; break;
2237 case 3: avctx->bit_rate = 320000; break;
2238 case 4: avctx->bit_rate = 384000; break;
2239 case 5: avctx->bit_rate = 448000; break;
2240 }
2241 }
2242
2243 /* validate bit rate */
2244 if (s->eac3) {
2245 int max_br, min_br, wpf, min_br_code;
2246 int num_blks_code, num_blocks, frame_samples;
2247 long long min_br_dist;
2248
2249 /* calculate min/max bitrate */
2250 /* TODO: More testing with 3 and 2 blocks. All E-AC-3 samples I've
2251 found use either 6 blocks or 1 block, even though 2 or 3 blocks
2252 would work as far as the bit rate is concerned. */
2253 for (num_blks_code = 3; num_blks_code >= 0; num_blks_code--) {
2254 num_blocks = ((int[]){ 1, 2, 3, 6 })[num_blks_code];
2255 frame_samples = AC3_BLOCK_SIZE * num_blocks;
2256 max_br = 2048 * s->sample_rate / frame_samples * 16;
2257 min_br = ((s->sample_rate + (frame_samples-1)) / frame_samples) * 16;
2258 if (avctx->bit_rate <= max_br)
2259 break;
2260 }
2261 if (avctx->bit_rate < min_br || avctx->bit_rate > max_br) {
2262 av_log(avctx, AV_LOG_ERROR, "invalid bit rate. must be %d to %d "
2263 "for this sample rate\n", min_br, max_br);
2264 return AVERROR(EINVAL);
2265 }
2266 s->num_blks_code = num_blks_code;
2267 s->num_blocks = num_blocks;
2268
2269 /* calculate words-per-frame for the selected bitrate */
2270 wpf = (avctx->bit_rate / 16) * frame_samples / s->sample_rate;
2271 av_assert1(wpf > 0 && wpf <= 2048);
2272
2273 /* find the closest AC-3 bitrate code to the selected bitrate.
2274 this is needed for lookup tables for bandwidth and coupling
2275 parameter selection */
2276 min_br_code = -1;
2277 min_br_dist = INT64_MAX;
2278 for (int i = 0; i < 19; i++) {
2279 long long br_dist = llabs(ff_ac3_bitrate_tab[i] * 1000 - avctx->bit_rate);
2280 if (br_dist < min_br_dist) {
2281 min_br_dist = br_dist;
2282 min_br_code = i;
2283 }
2284 }
2285
2286 /* make sure the minimum frame size is below the average frame size */
2287 s->frame_size_code = min_br_code << 1;
2288 while (wpf > 1 && wpf * s->sample_rate / AC3_FRAME_SIZE * 16 > avctx->bit_rate)
2289 wpf--;
2290 s->frame_size_min = 2 * wpf;
2291 } else {
2292 int best_br = 0, best_code = 0;
2293 long long best_diff = INT64_MAX;
2294 for (int i = 0; i < 19; i++) {
2295 int br = ff_ac3_bitrate_tab[i] * 1000;
2296 long long diff = llabs(br - avctx->bit_rate);
2297 if (diff < best_diff) {
2298 best_br = br;
2299 best_code = i;
2300 best_diff = diff;
2301 }
2302 if (!best_diff)
2303 break;
2304 }
2305 avctx->bit_rate = best_br;
2306 s->frame_size_code = best_code << 1;
2307 s->frame_size_min = 2 * ff_ac3_frame_size_tab[s->frame_size_code][s->bit_alloc.sr_code];
2308 s->num_blks_code = 0x3;
2309 s->num_blocks = 6;
2310 }
2311 s->bit_rate = avctx->bit_rate;
2312 s->frame_size = s->frame_size_min;
2313
2314 /* validate cutoff */
2315 if (avctx->cutoff < 0) {
2316 av_log(avctx, AV_LOG_ERROR, "invalid cutoff frequency\n");
2317 return AVERROR(EINVAL);
2318 }
2319 s->cutoff = avctx->cutoff;
2320 if (s->cutoff > (s->sample_rate >> 1))
2321 s->cutoff = s->sample_rate >> 1;
2322
2323 ret = ac3_validate_metadata(s);
2324 if (ret)
2325 return ret;
2326
2327 s->rematrixing_enabled = s->options.stereo_rematrixing &&
2328 (s->channel_mode == AC3_CHMODE_STEREO);
2329
2330 s->cpl_enabled = s->options.channel_coupling &&
2331 s->channel_mode >= AC3_CHMODE_STEREO;
2332
2333 return 0;
2334 }
2335
2336
2337 /*
2338 * Set bandwidth for all channels.
2339 * The user can optionally supply a cutoff frequency. Otherwise an appropriate
2340 * default value will be used.
2341 */
2342 static av_cold void set_bandwidth(AC3EncodeContext *s)
2343 {
2344 int blk, ch, av_uninit(cpl_start);
2345
2346 if (s->cutoff) {
2347 /* calculate bandwidth based on user-specified cutoff frequency */
2348 int fbw_coeffs;
2349 fbw_coeffs = s->cutoff * 2 * AC3_MAX_COEFS / s->sample_rate;
2350 s->bandwidth_code = av_clip((fbw_coeffs - 73) / 3, 0, 60);
2351 } else {
2352 /* use default bandwidth setting */
2353 s->bandwidth_code = ac3_bandwidth_tab[s->fbw_channels-1][s->bit_alloc.sr_code][s->frame_size_code/2];
2354 }
2355
2356 /* set number of coefficients for each channel */
2357 for (ch = 1; ch <= s->fbw_channels; ch++) {
2358 s->start_freq[ch] = 0;
2359 for (blk = 0; blk < s->num_blocks; blk++)
2360 s->blocks[blk].end_freq[ch] = s->bandwidth_code * 3 + 73;
2361 }
2362 /* LFE channel always has 7 coefs */
2363 if (s->lfe_on) {
2364 s->start_freq[s->lfe_channel] = 0;
2365 for (blk = 0; blk < s->num_blocks; blk++)
2366 s->blocks[blk].end_freq[ch] = 7;
2367 }
2368
2369 /* initialize coupling strategy */
2370 if (s->cpl_enabled) {
2371 if (s->options.cpl_start != AC3ENC_OPT_AUTO) {
2372 cpl_start = s->options.cpl_start;
2373 } else {
2374 cpl_start = ac3_coupling_start_tab[s->channel_mode-2][s->bit_alloc.sr_code][s->frame_size_code/2];
2375 if (cpl_start < 0) {
2376 if (s->options.channel_coupling == AC3ENC_OPT_AUTO)
2377 s->cpl_enabled = 0;
2378 else
2379 cpl_start = 15;
2380 }
2381 }
2382 }
2383 if (s->cpl_enabled) {
2384 int i, cpl_start_band, cpl_end_band;
2385 uint8_t *cpl_band_sizes = s->cpl_band_sizes;
2386
2387 cpl_end_band = s->bandwidth_code / 4 + 3;
2388 cpl_start_band = av_clip(cpl_start, 0, FFMIN(cpl_end_band-1, 15));
2389
2390 s->num_cpl_subbands = cpl_end_band - cpl_start_band;
2391
2392 s->num_cpl_bands = 1;
2393 *cpl_band_sizes = 12;
2394 for (i = cpl_start_band + 1; i < cpl_end_band; i++) {
2395 if (ff_eac3_default_cpl_band_struct[i]) {
2396 *cpl_band_sizes += 12;
2397 } else {
2398 s->num_cpl_bands++;
2399 cpl_band_sizes++;
2400 *cpl_band_sizes = 12;
2401 }
2402 }
2403
2404 s->start_freq[CPL_CH] = cpl_start_band * 12 + 37;
2405 s->cpl_end_freq = cpl_end_band * 12 + 37;
2406 for (blk = 0; blk < s->num_blocks; blk++)
2407 s->blocks[blk].end_freq[CPL_CH] = s->cpl_end_freq;
2408 }
2409 }
2410
2411
2412 static av_cold int allocate_buffers(AC3EncodeContext *s)
2413 {
2414 int blk, ch;
2415 int channels = s->channels + 1; /* includes coupling channel */
2416 int channel_blocks = channels * s->num_blocks;
2417 int total_coefs = AC3_MAX_COEFS * channel_blocks;
2418 uint8_t *cpl_coord_mant_buffer;
2419 const unsigned sampletype_size = SAMPLETYPE_SIZE(s);
2420
2421 for (int ch = 0; ch < s->channels; ch++) {
2422 s->planar_samples[ch] = av_mallocz(AC3_BLOCK_SIZE * sampletype_size);
2423 if (!s->planar_samples[ch])
2424 return AVERROR(ENOMEM);
2425 }
2426
2427 if (!FF_ALLOC_TYPED_ARRAY(s->bap_buffer, total_coefs) ||
2428 !FF_ALLOC_TYPED_ARRAY(s->bap1_buffer, total_coefs) ||
2429 !FF_ALLOCZ_TYPED_ARRAY(s->mdct_coef_buffer, total_coefs) ||
2430 !FF_ALLOC_TYPED_ARRAY(s->exp_buffer, total_coefs) ||
2431 !FF_ALLOC_TYPED_ARRAY(s->grouped_exp_buffer, channel_blocks * 128) ||
2432 !FF_ALLOC_TYPED_ARRAY(s->psd_buffer, total_coefs) ||
2433 !FF_ALLOC_TYPED_ARRAY(s->band_psd_buffer, channel_blocks * 64) ||
2434 !FF_ALLOC_TYPED_ARRAY(s->mask_buffer, channel_blocks * 64) ||
2435 !FF_ALLOC_TYPED_ARRAY(s->qmant_buffer, total_coefs))
2436 return AVERROR(ENOMEM);
2437
2438 if (!s->fixed_point) {
2439 if (!FF_ALLOCZ_TYPED_ARRAY(s->fixed_coef_buffer, total_coefs))
2440 return AVERROR(ENOMEM);
2441 }
2442 if (s->cpl_enabled) {
2443 if (!FF_ALLOC_TYPED_ARRAY(s->cpl_coord_buffer, channel_blocks * 32))
2444 return AVERROR(ENOMEM);
2445 cpl_coord_mant_buffer = s->cpl_coord_buffer + 16 * channel_blocks;
2446 }
2447 for (blk = 0; blk < s->num_blocks; blk++) {
2448 AC3Block *block = &s->blocks[blk];
2449
2450 for (ch = 0; ch < channels; ch++) {
2451 /* arrangement: block, channel, coeff */
2452 block->grouped_exp[ch] = &s->grouped_exp_buffer[128 * (blk * channels + ch)];
2453 block->psd[ch] = &s->psd_buffer [AC3_MAX_COEFS * (blk * channels + ch)];
2454 block->band_psd[ch] = &s->band_psd_buffer [64 * (blk * channels + ch)];
2455 block->mask[ch] = &s->mask_buffer [64 * (blk * channels + ch)];
2456 block->qmant[ch] = &s->qmant_buffer [AC3_MAX_COEFS * (blk * channels + ch)];
2457 if (s->cpl_enabled) {
2458 block->cpl_coord_exp[ch] = &s->cpl_coord_buffer [16 * (blk * channels + ch)];
2459 block->cpl_coord_mant[ch] = &cpl_coord_mant_buffer[16 * (blk * channels + ch)];
2460 }
2461
2462 /* arrangement: channel, block, coeff */
2463 block->exp[ch] = &s->exp_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2464 block->mdct_coef[ch] = &s->mdct_coef_buffer [AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2465 if (s->fixed_point)
2466 block->fixed_coef[ch] = (int32_t *)block->mdct_coef[ch];
2467 else
2468 block->fixed_coef[ch] = &s->fixed_coef_buffer[AC3_MAX_COEFS * (s->num_blocks * ch + blk)];
2469 }
2470 }
2471
2472 return 0;
2473 }
2474
2475
2476 av_cold int ff_ac3_encode_init(AVCodecContext *avctx)
2477 {
2478 static AVOnce init_static_once = AV_ONCE_INIT;
2479 AC3EncodeContext *s = avctx->priv_data;
2480 int ret, frame_size_58;
2481
2482 s->avctx = avctx;
2483
2484 ret = validate_options(s);
2485 if (ret)
2486 return ret;
2487
2488 avctx->frame_size = AC3_BLOCK_SIZE * s->num_blocks;
2489 avctx->initial_padding = AC3_BLOCK_SIZE;
2490
2491 s->bitstream_mode = avctx->audio_service_type;
2492 if (s->bitstream_mode == AV_AUDIO_SERVICE_TYPE_KARAOKE)
2493 s->bitstream_mode = 0x7;
2494
2495 s->bits_written = 0;
2496 s->samples_written = 0;
2497
2498 /* calculate crc_inv for both possible frame sizes */
2499 frame_size_58 = (( s->frame_size >> 2) + ( s->frame_size >> 4)) << 1;
2500 s->crc_inv[0] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2501 if (s->bit_alloc.sr_code == 1) {
2502 frame_size_58 = (((s->frame_size+2) >> 2) + ((s->frame_size+2) >> 4)) << 1;
2503 s->crc_inv[1] = pow_poly((CRC16_POLY >> 1), (8 * frame_size_58) - 16, CRC16_POLY);
2504 }
2505
2506 if (!s->output_frame_header)
2507 s->output_frame_header = ac3_output_frame_header;
2508
2509 set_bandwidth(s);
2510
2511 bit_alloc_init(s);
2512
2513 ret = allocate_buffers(s);
2514 if (ret)
2515 return ret;
2516
2517 ff_audiodsp_init(&s->adsp);
2518 ff_me_cmp_init(&s->mecc, avctx);
2519 ff_ac3dsp_init(&s->ac3dsp);
2520
2521 dprint_options(s);
2522
2523 ff_thread_once(&init_static_once, exponent_init);
2524
2525 return 0;
2526 }