3 * Copyright (c) 2003 The ffmpeg Project
5 * This file is part of Libav.
7 * Libav 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 * Libav 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 Libav; 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.
40 #include "libavutil/intreadwrite.h"
42 #include "bytestream.h"
44 typedef struct DPCMContext {
46 short roq_square_array[256];
47 int sample[2]; ///< previous sample (for SOL_DPCM)
48 const int *sol_table;//for SOL_DPCM
51 static const int interplay_delta_table[] = {
52 0, 1, 2, 3, 4, 5, 6, 7,
53 8, 9, 10, 11, 12, 13, 14, 15,
54 16, 17, 18, 19, 20, 21, 22, 23,
55 24, 25, 26, 27, 28, 29, 30, 31,
56 32, 33, 34, 35, 36, 37, 38, 39,
57 40, 41, 42, 43, 47, 51, 56, 61,
58 66, 72, 79, 86, 94, 102, 112, 122,
59 133, 145, 158, 173, 189, 206, 225, 245,
60 267, 292, 318, 348, 379, 414, 452, 493,
61 538, 587, 640, 699, 763, 832, 908, 991,
62 1081, 1180, 1288, 1405, 1534, 1673, 1826, 1993,
63 2175, 2373, 2590, 2826, 3084, 3365, 3672, 4008,
64 4373, 4772, 5208, 5683, 6202, 6767, 7385, 8059,
65 8794, 9597, 10472, 11428, 12471, 13609, 14851, 16206,
66 17685, 19298, 21060, 22981, 25078, 27367, 29864, 32589,
67 -29973, -26728, -23186, -19322, -15105, -10503, -5481, -1,
68 1, 1, 5481, 10503, 15105, 19322, 23186, 26728,
69 29973, -32589, -29864, -27367, -25078, -22981, -21060, -19298,
70 -17685, -16206, -14851, -13609, -12471, -11428, -10472, -9597,
71 -8794, -8059, -7385, -6767, -6202, -5683, -5208, -4772,
72 -4373, -4008, -3672, -3365, -3084, -2826, -2590, -2373,
73 -2175, -1993, -1826, -1673, -1534, -1405, -1288, -1180,
74 -1081, -991, -908, -832, -763, -699, -640, -587,
75 -538, -493, -452, -414, -379, -348, -318, -292,
76 -267, -245, -225, -206, -189, -173, -158, -145,
77 -133, -122, -112, -102, -94, -86, -79, -72,
78 -66, -61, -56, -51, -47, -43, -42, -41,
79 -40, -39, -38, -37, -36, -35, -34, -33,
80 -32, -31, -30, -29, -28, -27, -26, -25,
81 -24, -23, -22, -21, -20, -19, -18, -17,
82 -16, -15, -14, -13, -12, -11, -10, -9,
83 -8, -7, -6, -5, -4, -3, -2, -1
87 static const int sol_table_old[16] =
88 { 0x0, 0x1, 0x2 , 0x3, 0x6, 0xA, 0xF, 0x15,
89 -0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1, 0x0};
91 static const int sol_table_new[16] =
92 { 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
93 0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15};
95 static const int sol_table_16[128] = {
96 0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
97 0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
98 0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
99 0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
100 0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
101 0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
102 0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
103 0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
104 0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
105 0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
106 0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
107 0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
108 0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
113 static av_cold int dpcm_decode_init(AVCodecContext *avctx)
115 DPCMContext *s = avctx->priv_data;
119 s->channels = avctx->channels;
120 s->sample[0] = s->sample[1] = 0;
122 switch(avctx->codec->id) {
124 case CODEC_ID_ROQ_DPCM:
125 /* initialize square table */
126 for (i = 0; i < 128; i++) {
128 s->roq_square_array[i] = square;
129 s->roq_square_array[i + 128] = -square;
134 case CODEC_ID_SOL_DPCM:
135 switch(avctx->codec_tag){
137 s->sol_table=sol_table_old;
138 s->sample[0] = s->sample[1] = 0x80;
141 s->sol_table=sol_table_new;
142 s->sample[0] = s->sample[1] = 0x80;
145 s->sol_table=sol_table_16;
148 av_log(avctx, AV_LOG_ERROR, "Unknown SOL subcodec\n");
157 if (avctx->codec->id == CODEC_ID_SOL_DPCM && avctx->codec_tag != 3)
158 avctx->sample_fmt = AV_SAMPLE_FMT_U8;
160 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
165 static int dpcm_decode_frame(AVCodecContext *avctx,
166 void *data, int *data_size,
169 const uint8_t *buf = avpkt->data;
170 int buf_size = avpkt->size;
171 const uint8_t *buf_end = buf + buf_size;
172 DPCMContext *s = avctx->priv_data;
176 int stereo = s->channels - 1;
177 short *output_samples = data;
182 /* calculate output size */
183 switch(avctx->codec->id) {
184 case CODEC_ID_ROQ_DPCM:
187 case CODEC_ID_INTERPLAY_DPCM:
188 out = buf_size - 6 - s->channels;
190 case CODEC_ID_XAN_DPCM:
191 out = buf_size - 2 * s->channels;
193 case CODEC_ID_SOL_DPCM:
194 if (avctx->codec_tag != 3)
200 out *= av_get_bytes_per_sample(avctx->sample_fmt);
202 if (*data_size < out) {
203 av_log(avctx, AV_LOG_ERROR, "output buffer is too small\n");
204 return AVERROR(EINVAL);
207 switch(avctx->codec->id) {
209 case CODEC_ID_ROQ_DPCM:
213 predictor[1] = (int16_t)(bytestream_get_byte(&buf) << 8);
214 predictor[0] = (int16_t)(bytestream_get_byte(&buf) << 8);
216 predictor[0] = (int16_t)bytestream_get_le16(&buf);
219 /* decode the samples */
220 while (buf < buf_end) {
221 predictor[ch] += s->roq_square_array[*buf++];
222 predictor[ch] = av_clip_int16(predictor[ch]);
223 *output_samples++ = predictor[ch];
230 case CODEC_ID_INTERPLAY_DPCM:
231 buf += 6; /* skip over the stream mask and stream length */
233 for (ch = 0; ch < s->channels; ch++) {
234 predictor[ch] = (int16_t)bytestream_get_le16(&buf);
235 *output_samples++ = predictor[ch];
239 while (buf < buf_end) {
240 predictor[ch] += interplay_delta_table[*buf++];
241 predictor[ch] = av_clip_int16(predictor[ch]);
242 *output_samples++ = predictor[ch];
249 case CODEC_ID_XAN_DPCM:
251 int shift[2] = { 4, 4 };
253 for (ch = 0; ch < s->channels; ch++)
254 predictor[ch] = (int16_t)bytestream_get_le16(&buf);
257 while (buf < buf_end) {
259 int16_t diff = (n & 0xFC) << 8;
263 shift[ch] -= (2 * (n & 3));
264 /* saturate the shifter to a lower limit of 0 */
269 predictor[ch] += diff;
271 predictor[ch] = av_clip_int16(predictor[ch]);
272 *output_samples++ = predictor[ch];
279 case CODEC_ID_SOL_DPCM:
280 if (avctx->codec_tag != 3) {
281 uint8_t *output_samples_u8 = data;
282 while (buf < buf_end) {
285 s->sample[0] += s->sol_table[n >> 4];
286 s->sample[0] = av_clip_uint8(s->sample[0]);
287 *output_samples_u8++ = s->sample[0];
289 s->sample[stereo] += s->sol_table[n & 0x0F];
290 s->sample[stereo] = av_clip_uint8(s->sample[stereo]);
291 *output_samples_u8++ = s->sample[stereo];
294 while (buf < buf_end) {
296 if (n & 0x80) s->sample[ch] -= s->sol_table[n & 0x7F];
297 else s->sample[ch] += s->sol_table[n & 0x7F];
298 s->sample[ch] = av_clip_int16(s->sample[ch]);
299 *output_samples++ = s->sample[ch];
311 #define DPCM_DECODER(id_, name_, long_name_) \
312 AVCodec ff_ ## name_ ## _decoder = { \
314 .type = AVMEDIA_TYPE_AUDIO, \
316 .priv_data_size = sizeof(DPCMContext), \
317 .init = dpcm_decode_init, \
318 .decode = dpcm_decode_frame, \
319 .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
322 DPCM_DECODER(CODEC_ID_INTERPLAY_DPCM, interplay_dpcm, "DPCM Interplay");
323 DPCM_DECODER(CODEC_ID_ROQ_DPCM, roq_dpcm, "DPCM id RoQ");
324 DPCM_DECODER(CODEC_ID_SOL_DPCM, sol_dpcm, "DPCM Sol");
325 DPCM_DECODER(CODEC_ID_XAN_DPCM, xan_dpcm, "DPCM Xan");