3 * Copyright (c) 2003 The ffmpeg Project.
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
24 * Assorted DPCM (differential pulse code modulation) audio codecs
25 * by Mike Melanson (melanson@pcisys.net)
26 * Xan DPCM decoder by Mario Brito (mbrito@student.dei.uc.pt)
27 * for more information on the specific data formats, visit:
28 * http://www.pcisys.net/~melanson/codecs/simpleaudio.html
29 * SOL DPCMs implemented by Konstantin Shishkov
31 * Note about using the Xan DPCM decoder: Xan DPCM is used in AVI files
32 * found in the Wing Commander IV computer game. These AVI files contain
33 * WAVEFORMAT headers which report the audio format as 0x01: raw PCM.
34 * Clearly incorrect. To detect Xan DPCM, you will probably have to
35 * special-case your AVI demuxer to use Xan DPCM if the file uses 'Xxan'
36 * (Xan video) for its video codec. Alternately, such AVI files also contain
37 * the fourcc 'Axan' in the 'auds' chunk of the AVI header.
42 typedef struct DPCMContext {
44 short roq_square_array[256];
45 long sample[2];//for SOL_DPCM
46 const int *sol_table;//for SOL_DPCM
49 #define SATURATE_S16(x) if (x < -32768) x = -32768; \
50 else if (x > 32767) x = 32767;
51 #define SE_16BIT(x) if (x & 0x8000) x -= 0x10000;
53 static int interplay_delta_table[] = {
54 0, 1, 2, 3, 4, 5, 6, 7,
55 8, 9, 10, 11, 12, 13, 14, 15,
56 16, 17, 18, 19, 20, 21, 22, 23,
57 24, 25, 26, 27, 28, 29, 30, 31,
58 32, 33, 34, 35, 36, 37, 38, 39,
59 40, 41, 42, 43, 47, 51, 56, 61,
60 66, 72, 79, 86, 94, 102, 112, 122,
61 133, 145, 158, 173, 189, 206, 225, 245,
62 267, 292, 318, 348, 379, 414, 452, 493,
63 538, 587, 640, 699, 763, 832, 908, 991,
64 1081, 1180, 1288, 1405, 1534, 1673, 1826, 1993,
65 2175, 2373, 2590, 2826, 3084, 3365, 3672, 4008,
66 4373, 4772, 5208, 5683, 6202, 6767, 7385, 8059,
67 8794, 9597, 10472, 11428, 12471, 13609, 14851, 16206,
68 17685, 19298, 21060, 22981, 25078, 27367, 29864, 32589,
69 -29973, -26728, -23186, -19322, -15105, -10503, -5481, -1,
70 1, 1, 5481, 10503, 15105, 19322, 23186, 26728,
71 29973, -32589, -29864, -27367, -25078, -22981, -21060, -19298,
72 -17685, -16206, -14851, -13609, -12471, -11428, -10472, -9597,
73 -8794, -8059, -7385, -6767, -6202, -5683, -5208, -4772,
74 -4373, -4008, -3672, -3365, -3084, -2826, -2590, -2373,
75 -2175, -1993, -1826, -1673, -1534, -1405, -1288, -1180,
76 -1081, -991, -908, -832, -763, -699, -640, -587,
77 -538, -493, -452, -414, -379, -348, -318, -292,
78 -267, -245, -225, -206, -189, -173, -158, -145,
79 -133, -122, -112, -102, -94, -86, -79, -72,
80 -66, -61, -56, -51, -47, -43, -42, -41,
81 -40, -39, -38, -37, -36, -35, -34, -33,
82 -32, -31, -30, -29, -28, -27, -26, -25,
83 -24, -23, -22, -21, -20, -19, -18, -17,
84 -16, -15, -14, -13, -12, -11, -10, -9,
85 -8, -7, -6, -5, -4, -3, -2, -1
89 static const int sol_table_old[16] =
90 { 0x0, 0x1, 0x2 , 0x3, 0x6, 0xA, 0xF, 0x15,
91 -0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1, 0x0};
93 static const int sol_table_new[16] =
94 { 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
95 0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15};
97 static const int sol_table_16[128] = {
98 0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
99 0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
100 0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
101 0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
102 0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
103 0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
104 0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
105 0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
106 0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
107 0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
108 0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
109 0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
110 0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
115 static int dpcm_decode_init(AVCodecContext *avctx)
117 DPCMContext *s = avctx->priv_data;
121 s->channels = avctx->channels;
122 s->sample[0] = s->sample[1] = 0;
124 switch(avctx->codec->id) {
126 case CODEC_ID_ROQ_DPCM:
127 /* initialize square table */
128 for (i = 0; i < 128; i++) {
130 s->roq_square_array[i] = square;
131 s->roq_square_array[i + 128] = -square;
136 case CODEC_ID_SOL_DPCM:
137 switch(avctx->codec_tag){
139 s->sol_table=sol_table_old;
140 s->sample[0] = s->sample[1] = 0x80;
143 s->sol_table=sol_table_new;
144 s->sample[0] = s->sample[1] = 0x80;
147 s->sol_table=sol_table_16;
150 av_log(avctx, AV_LOG_ERROR, "Unknown SOL subcodec\n");
162 static int dpcm_decode_frame(AVCodecContext *avctx,
163 void *data, int *data_size,
164 uint8_t *buf, int buf_size)
166 DPCMContext *s = avctx->priv_data;
169 int channel_number = 0;
170 short *output_samples = data;
178 switch(avctx->codec->id) {
180 case CODEC_ID_ROQ_DPCM:
181 if (s->channels == 1)
182 predictor[0] = AV_RL16(&buf[6]);
184 predictor[0] = buf[7] << 8;
185 predictor[1] = buf[6] << 8;
187 SE_16BIT(predictor[0]);
188 SE_16BIT(predictor[1]);
190 /* decode the samples */
191 for (in = 8, out = 0; in < buf_size; in++, out++) {
192 predictor[channel_number] += s->roq_square_array[buf[in]];
193 SATURATE_S16(predictor[channel_number]);
194 output_samples[out] = predictor[channel_number];
197 channel_number ^= s->channels - 1;
201 case CODEC_ID_INTERPLAY_DPCM:
202 in = 6; /* skip over the stream mask and stream length */
203 predictor[0] = AV_RL16(&buf[in]);
205 SE_16BIT(predictor[0])
206 output_samples[out++] = predictor[0];
207 if (s->channels == 2) {
208 predictor[1] = AV_RL16(&buf[in]);
210 SE_16BIT(predictor[1])
211 output_samples[out++] = predictor[1];
214 while (in < buf_size) {
215 predictor[channel_number] += interplay_delta_table[buf[in++]];
216 SATURATE_S16(predictor[channel_number]);
217 output_samples[out++] = predictor[channel_number];
220 channel_number ^= s->channels - 1;
225 case CODEC_ID_XAN_DPCM:
227 shift[0] = shift[1] = 4;
228 predictor[0] = AV_RL16(&buf[in]);
230 SE_16BIT(predictor[0]);
231 if (s->channels == 2) {
232 predictor[1] = AV_RL16(&buf[in]);
234 SE_16BIT(predictor[1]);
237 while (in < buf_size) {
239 diff = (byte & 0xFC) << 8;
240 if ((byte & 0x03) == 3)
241 shift[channel_number]++;
243 shift[channel_number] -= (2 * (byte & 3));
244 /* saturate the shifter to a lower limit of 0 */
245 if (shift[channel_number] < 0)
246 shift[channel_number] = 0;
248 diff >>= shift[channel_number];
249 predictor[channel_number] += diff;
251 SATURATE_S16(predictor[channel_number]);
252 output_samples[out++] = predictor[channel_number];
255 channel_number ^= s->channels - 1;
258 case CODEC_ID_SOL_DPCM:
260 if (avctx->codec_tag != 3) {
261 while (in < buf_size) {
263 n1 = (buf[in] >> 4) & 0xF;
264 n2 = buf[in++] & 0xF;
265 s->sample[0] += s->sol_table[n1];
266 if (s->sample[0] < 0) s->sample[0] = 0;
267 if (s->sample[0] > 255) s->sample[0] = 255;
268 output_samples[out++] = (s->sample[0] - 128) << 8;
269 s->sample[s->channels - 1] += s->sol_table[n2];
270 if (s->sample[s->channels - 1] < 0) s->sample[s->channels - 1] = 0;
271 if (s->sample[s->channels - 1] > 255) s->sample[s->channels - 1] = 255;
272 output_samples[out++] = (s->sample[s->channels - 1] - 128) << 8;
275 while (in < buf_size) {
278 if (n & 0x80) s->sample[channel_number] -= s->sol_table[n & 0x7F];
279 else s->sample[channel_number] += s->sol_table[n & 0x7F];
280 SATURATE_S16(s->sample[channel_number]);
281 output_samples[out++] = s->sample[channel_number];
283 channel_number ^= s->channels - 1;
289 *data_size = out * sizeof(short);
293 AVCodec roq_dpcm_decoder = {
304 AVCodec interplay_dpcm_decoder = {
307 CODEC_ID_INTERPLAY_DPCM,
315 AVCodec xan_dpcm_decoder = {
326 AVCodec sol_dpcm_decoder = {