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.
40 #include "libavutil/intreadwrite.h"
42 #include "bytestream.h"
46 typedef struct DPCMContext {
48 int sample[2]; ///< previous sample (for SOL_DPCM)
49 const int8_t *sol_table; ///< delta table for SOL_DPCM
52 static const int16_t interplay_delta_table[] = {
53 0, 1, 2, 3, 4, 5, 6, 7,
54 8, 9, 10, 11, 12, 13, 14, 15,
55 16, 17, 18, 19, 20, 21, 22, 23,
56 24, 25, 26, 27, 28, 29, 30, 31,
57 32, 33, 34, 35, 36, 37, 38, 39,
58 40, 41, 42, 43, 47, 51, 56, 61,
59 66, 72, 79, 86, 94, 102, 112, 122,
60 133, 145, 158, 173, 189, 206, 225, 245,
61 267, 292, 318, 348, 379, 414, 452, 493,
62 538, 587, 640, 699, 763, 832, 908, 991,
63 1081, 1180, 1288, 1405, 1534, 1673, 1826, 1993,
64 2175, 2373, 2590, 2826, 3084, 3365, 3672, 4008,
65 4373, 4772, 5208, 5683, 6202, 6767, 7385, 8059,
66 8794, 9597, 10472, 11428, 12471, 13609, 14851, 16206,
67 17685, 19298, 21060, 22981, 25078, 27367, 29864, 32589,
68 -29973, -26728, -23186, -19322, -15105, -10503, -5481, -1,
69 1, 1, 5481, 10503, 15105, 19322, 23186, 26728,
70 29973, -32589, -29864, -27367, -25078, -22981, -21060, -19298,
71 -17685, -16206, -14851, -13609, -12471, -11428, -10472, -9597,
72 -8794, -8059, -7385, -6767, -6202, -5683, -5208, -4772,
73 -4373, -4008, -3672, -3365, -3084, -2826, -2590, -2373,
74 -2175, -1993, -1826, -1673, -1534, -1405, -1288, -1180,
75 -1081, -991, -908, -832, -763, -699, -640, -587,
76 -538, -493, -452, -414, -379, -348, -318, -292,
77 -267, -245, -225, -206, -189, -173, -158, -145,
78 -133, -122, -112, -102, -94, -86, -79, -72,
79 -66, -61, -56, -51, -47, -43, -42, -41,
80 -40, -39, -38, -37, -36, -35, -34, -33,
81 -32, -31, -30, -29, -28, -27, -26, -25,
82 -24, -23, -22, -21, -20, -19, -18, -17,
83 -16, -15, -14, -13, -12, -11, -10, -9,
84 -8, -7, -6, -5, -4, -3, -2, -1
88 static const int8_t sol_table_old[16] = {
89 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
90 -0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1, 0x0
93 static const int8_t sol_table_new[16] = {
94 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
95 0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15
98 static const int16_t sol_table_16[128] = {
99 0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
100 0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
101 0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
102 0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
103 0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
104 0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
105 0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
106 0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
107 0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
108 0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
109 0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
110 0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
111 0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
115 static av_cold int dpcm_decode_init(AVCodecContext *avctx)
117 DPCMContext *s = avctx->priv_data;
120 if (avctx->channels < 1 || avctx->channels > 2) {
121 av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
122 return AVERROR(EINVAL);
125 s->sample[0] = s->sample[1] = 0;
127 switch(avctx->codec->id) {
129 case AV_CODEC_ID_ROQ_DPCM:
130 /* initialize square table */
131 for (i = 0; i < 128; i++) {
132 int16_t square = i * i;
133 s->array[i ] = square;
134 s->array[i + 128] = -square;
138 case AV_CODEC_ID_SOL_DPCM:
139 switch(avctx->codec_tag){
141 s->sol_table = sol_table_old;
142 s->sample[0] = s->sample[1] = 0x80;
145 s->sol_table = sol_table_new;
146 s->sample[0] = s->sample[1] = 0x80;
151 av_log(avctx, AV_LOG_ERROR, "Unknown SOL subcodec\n");
156 case AV_CODEC_ID_SDX2_DPCM:
157 for (i = -128; i < 128; i++) {
158 int16_t square = i * i * 2;
159 s->array[i+128] = i < 0 ? -square: square;
163 case AV_CODEC_ID_GREMLIN_DPCM: {
169 for (i = 0; i < 127; i++) {
170 delta += (code >> 5);
174 s->array[i*2 + 1] = delta;
175 s->array[i*2 + 2] = -delta;
177 s->array[255] = delta + (code >> 5);
185 if (avctx->codec->id == AV_CODEC_ID_SOL_DPCM && avctx->codec_tag != 3)
186 avctx->sample_fmt = AV_SAMPLE_FMT_U8;
188 avctx->sample_fmt = AV_SAMPLE_FMT_S16;
194 static int dpcm_decode_frame(AVCodecContext *avctx, void *data,
195 int *got_frame_ptr, AVPacket *avpkt)
197 int buf_size = avpkt->size;
198 DPCMContext *s = avctx->priv_data;
199 AVFrame *frame = data;
203 int stereo = avctx->channels - 1;
204 int16_t *output_samples, *samples_end;
207 if (stereo && (buf_size & 1))
209 bytestream2_init(&gb, avpkt->data, buf_size);
211 /* calculate output size */
212 switch(avctx->codec->id) {
213 case AV_CODEC_ID_ROQ_DPCM:
216 case AV_CODEC_ID_INTERPLAY_DPCM:
217 out = buf_size - 6 - avctx->channels;
219 case AV_CODEC_ID_XAN_DPCM:
220 out = buf_size - 2 * avctx->channels;
222 case AV_CODEC_ID_SOL_DPCM:
223 if (avctx->codec_tag != 3)
228 case AV_CODEC_ID_GREMLIN_DPCM:
229 case AV_CODEC_ID_SDX2_DPCM:
234 av_log(avctx, AV_LOG_ERROR, "packet is too small\n");
235 return AVERROR(EINVAL);
237 if (out % avctx->channels) {
238 av_log(avctx, AV_LOG_WARNING, "channels have differing number of samples\n");
241 /* get output buffer */
242 frame->nb_samples = (out + avctx->channels - 1) / avctx->channels;
243 if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
245 output_samples = (int16_t *)frame->data[0];
246 samples_end = output_samples + out;
248 switch(avctx->codec->id) {
250 case AV_CODEC_ID_ROQ_DPCM:
251 bytestream2_skipu(&gb, 6);
254 predictor[1] = sign_extend(bytestream2_get_byteu(&gb) << 8, 16);
255 predictor[0] = sign_extend(bytestream2_get_byteu(&gb) << 8, 16);
257 predictor[0] = sign_extend(bytestream2_get_le16u(&gb), 16);
260 /* decode the samples */
261 while (output_samples < samples_end) {
262 predictor[ch] += s->array[bytestream2_get_byteu(&gb)];
263 predictor[ch] = av_clip_int16(predictor[ch]);
264 *output_samples++ = predictor[ch];
271 case AV_CODEC_ID_INTERPLAY_DPCM:
272 bytestream2_skipu(&gb, 6); /* skip over the stream mask and stream length */
274 for (ch = 0; ch < avctx->channels; ch++) {
275 predictor[ch] = sign_extend(bytestream2_get_le16u(&gb), 16);
276 *output_samples++ = predictor[ch];
280 while (output_samples < samples_end) {
281 predictor[ch] += interplay_delta_table[bytestream2_get_byteu(&gb)];
282 predictor[ch] = av_clip_int16(predictor[ch]);
283 *output_samples++ = predictor[ch];
290 case AV_CODEC_ID_XAN_DPCM:
292 int shift[2] = { 4, 4 };
294 for (ch = 0; ch < avctx->channels; ch++)
295 predictor[ch] = sign_extend(bytestream2_get_le16u(&gb), 16);
298 while (output_samples < samples_end) {
299 int diff = bytestream2_get_byteu(&gb);
305 shift[ch] -= (2 * n);
306 diff = sign_extend((diff &~ 3) << 8, 16);
308 /* saturate the shifter to a lower limit of 0 */
313 predictor[ch] += diff;
315 predictor[ch] = av_clip_int16(predictor[ch]);
316 *output_samples++ = predictor[ch];
323 case AV_CODEC_ID_SOL_DPCM:
324 if (avctx->codec_tag != 3) {
325 uint8_t *output_samples_u8 = frame->data[0],
326 *samples_end_u8 = output_samples_u8 + out;
327 while (output_samples_u8 < samples_end_u8) {
328 int n = bytestream2_get_byteu(&gb);
330 s->sample[0] += s->sol_table[n >> 4];
331 s->sample[0] = av_clip_uint8(s->sample[0]);
332 *output_samples_u8++ = s->sample[0];
334 s->sample[stereo] += s->sol_table[n & 0x0F];
335 s->sample[stereo] = av_clip_uint8(s->sample[stereo]);
336 *output_samples_u8++ = s->sample[stereo];
339 while (output_samples < samples_end) {
340 int n = bytestream2_get_byteu(&gb);
341 if (n & 0x80) s->sample[ch] -= sol_table_16[n & 0x7F];
342 else s->sample[ch] += sol_table_16[n & 0x7F];
343 s->sample[ch] = av_clip_int16(s->sample[ch]);
344 *output_samples++ = s->sample[ch];
351 case AV_CODEC_ID_SDX2_DPCM:
352 while (output_samples < samples_end) {
353 int8_t n = bytestream2_get_byteu(&gb);
357 s->sample[ch] += s->array[n + 128];
358 s->sample[ch] = av_clip_int16(s->sample[ch]);
359 *output_samples++ = s->sample[ch];
364 case AV_CODEC_ID_GREMLIN_DPCM: {
367 while (output_samples < samples_end) {
368 uint8_t n = bytestream2_get_byteu(&gb);
370 *output_samples++ = s->sample[idx] += s->array[n];
382 #define DPCM_DECODER(id_, name_, long_name_) \
383 AVCodec ff_ ## name_ ## _decoder = { \
385 .long_name = NULL_IF_CONFIG_SMALL(long_name_), \
386 .type = AVMEDIA_TYPE_AUDIO, \
388 .priv_data_size = sizeof(DPCMContext), \
389 .init = dpcm_decode_init, \
390 .decode = dpcm_decode_frame, \
391 .capabilities = AV_CODEC_CAP_DR1, \
394 DPCM_DECODER(AV_CODEC_ID_GREMLIN_DPCM, gremlin_dpcm, "DPCM Gremlin");
395 DPCM_DECODER(AV_CODEC_ID_INTERPLAY_DPCM, interplay_dpcm, "DPCM Interplay");
396 DPCM_DECODER(AV_CODEC_ID_ROQ_DPCM, roq_dpcm, "DPCM id RoQ");
397 DPCM_DECODER(AV_CODEC_ID_SDX2_DPCM, sdx2_dpcm, "DPCM Squareroot-Delta-Exact");
398 DPCM_DECODER(AV_CODEC_ID_SOL_DPCM, sol_dpcm, "DPCM Sol");
399 DPCM_DECODER(AV_CODEC_ID_XAN_DPCM, xan_dpcm, "DPCM Xan");