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FFmpeg/libavcodec/dpcm.c
Stefano Sabatini 72415b2adb Define AVMediaType enum, and use it instead of enum CodecType, which 
is deprecated and will be dropped at the next major bump.

Originally committed as revision 22735 to svn://svn.ffmpeg.org/ffmpeg/trunk
2010-03-30 23:30:55 +00:00

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/*
* Assorted DPCM codecs
* Copyright (c) 2003 The ffmpeg Project
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file: dpcm.c
* Assorted DPCM (differential pulse code modulation) audio codecs
* by Mike Melanson (melanson@pcisys.net)
* Xan DPCM decoder by Mario Brito (mbrito@student.dei.uc.pt)
* for more information on the specific data formats, visit:
* http://www.pcisys.net/~melanson/codecs/simpleaudio.html
* SOL DPCMs implemented by Konstantin Shishkov
*
* Note about using the Xan DPCM decoder: Xan DPCM is used in AVI files
* found in the Wing Commander IV computer game. These AVI files contain
* WAVEFORMAT headers which report the audio format as 0x01: raw PCM.
* Clearly incorrect. To detect Xan DPCM, you will probably have to
* special-case your AVI demuxer to use Xan DPCM if the file uses 'Xxan'
* (Xan video) for its video codec. Alternately, such AVI files also contain
* the fourcc 'Axan' in the 'auds' chunk of the AVI header.
*/
#include "libavutil/intreadwrite.h"
#include "avcodec.h"
typedef struct DPCMContext {
int channels;
short roq_square_array[256];
long sample[2];//for SOL_DPCM
const int *sol_table;//for SOL_DPCM
} DPCMContext;
#define SE_16BIT(x) if (x & 0x8000) x -= 0x10000;
static const int interplay_delta_table[] = {
0, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15,
16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, 30, 31,
32, 33, 34, 35, 36, 37, 38, 39,
40, 41, 42, 43, 47, 51, 56, 61,
66, 72, 79, 86, 94, 102, 112, 122,
133, 145, 158, 173, 189, 206, 225, 245,
267, 292, 318, 348, 379, 414, 452, 493,
538, 587, 640, 699, 763, 832, 908, 991,
1081, 1180, 1288, 1405, 1534, 1673, 1826, 1993,
2175, 2373, 2590, 2826, 3084, 3365, 3672, 4008,
4373, 4772, 5208, 5683, 6202, 6767, 7385, 8059,
8794, 9597, 10472, 11428, 12471, 13609, 14851, 16206,
17685, 19298, 21060, 22981, 25078, 27367, 29864, 32589,
-29973, -26728, -23186, -19322, -15105, -10503, -5481, -1,
1, 1, 5481, 10503, 15105, 19322, 23186, 26728,
29973, -32589, -29864, -27367, -25078, -22981, -21060, -19298,
-17685, -16206, -14851, -13609, -12471, -11428, -10472, -9597,
-8794, -8059, -7385, -6767, -6202, -5683, -5208, -4772,
-4373, -4008, -3672, -3365, -3084, -2826, -2590, -2373,
-2175, -1993, -1826, -1673, -1534, -1405, -1288, -1180,
-1081, -991, -908, -832, -763, -699, -640, -587,
-538, -493, -452, -414, -379, -348, -318, -292,
-267, -245, -225, -206, -189, -173, -158, -145,
-133, -122, -112, -102, -94, -86, -79, -72,
-66, -61, -56, -51, -47, -43, -42, -41,
-40, -39, -38, -37, -36, -35, -34, -33,
-32, -31, -30, -29, -28, -27, -26, -25,
-24, -23, -22, -21, -20, -19, -18, -17,
-16, -15, -14, -13, -12, -11, -10, -9,
-8, -7, -6, -5, -4, -3, -2, -1
};
static const int sol_table_old[16] =
{ 0x0, 0x1, 0x2 , 0x3, 0x6, 0xA, 0xF, 0x15,
-0x15, -0xF, -0xA, -0x6, -0x3, -0x2, -0x1, 0x0};
static const int sol_table_new[16] =
{ 0x0, 0x1, 0x2, 0x3, 0x6, 0xA, 0xF, 0x15,
0x0, -0x1, -0x2, -0x3, -0x6, -0xA, -0xF, -0x15};
static const int sol_table_16[128] = {
0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080,
0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120,
0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0,
0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230,
0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280,
0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0,
0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320,
0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370,
0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0,
0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480,
0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700,
0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00,
0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000
};
static av_cold int dpcm_decode_init(AVCodecContext *avctx)
{
DPCMContext *s = avctx->priv_data;
int i;
short square;
s->channels = avctx->channels;
s->sample[0] = s->sample[1] = 0;
switch(avctx->codec->id) {
case CODEC_ID_ROQ_DPCM:
/* initialize square table */
for (i = 0; i < 128; i++) {
square = i * i;
s->roq_square_array[i] = square;
s->roq_square_array[i + 128] = -square;
}
break;
case CODEC_ID_SOL_DPCM:
switch(avctx->codec_tag){
case 1:
s->sol_table=sol_table_old;
s->sample[0] = s->sample[1] = 0x80;
break;
case 2:
s->sol_table=sol_table_new;
s->sample[0] = s->sample[1] = 0x80;
break;
case 3:
s->sol_table=sol_table_16;
break;
default:
av_log(avctx, AV_LOG_ERROR, "Unknown SOL subcodec\n");
return -1;
}
break;
default:
break;
}
avctx->sample_fmt = SAMPLE_FMT_S16;
return 0;
}
static int dpcm_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
AVPacket *avpkt)
{
const uint8_t *buf = avpkt->data;
int buf_size = avpkt->size;
DPCMContext *s = avctx->priv_data;
int in, out = 0;
int predictor[2];
int channel_number = 0;
short *output_samples = data;
int shift[2];
unsigned char byte;
short diff;
if (!buf_size)
return 0;
// almost every DPCM variant expands one byte of data into two
if(*data_size/2 < buf_size)
return -1;
switch(avctx->codec->id) {
case CODEC_ID_ROQ_DPCM:
if (s->channels == 1)
predictor[0] = AV_RL16(&buf[6]);
else {
predictor[0] = buf[7] << 8;
predictor[1] = buf[6] << 8;
}
SE_16BIT(predictor[0]);
SE_16BIT(predictor[1]);
/* decode the samples */
for (in = 8, out = 0; in < buf_size; in++, out++) {
predictor[channel_number] += s->roq_square_array[buf[in]];
predictor[channel_number] = av_clip_int16(predictor[channel_number]);
output_samples[out] = predictor[channel_number];
/* toggle channel */
channel_number ^= s->channels - 1;
}
break;
case CODEC_ID_INTERPLAY_DPCM:
in = 6; /* skip over the stream mask and stream length */
predictor[0] = AV_RL16(&buf[in]);
in += 2;
SE_16BIT(predictor[0])
output_samples[out++] = predictor[0];
if (s->channels == 2) {
predictor[1] = AV_RL16(&buf[in]);
in += 2;
SE_16BIT(predictor[1])
output_samples[out++] = predictor[1];
}
while (in < buf_size) {
predictor[channel_number] += interplay_delta_table[buf[in++]];
predictor[channel_number] = av_clip_int16(predictor[channel_number]);
output_samples[out++] = predictor[channel_number];
/* toggle channel */
channel_number ^= s->channels - 1;
}
break;
case CODEC_ID_XAN_DPCM:
in = 0;
shift[0] = shift[1] = 4;
predictor[0] = AV_RL16(&buf[in]);
in += 2;
SE_16BIT(predictor[0]);
if (s->channels == 2) {
predictor[1] = AV_RL16(&buf[in]);
in += 2;
SE_16BIT(predictor[1]);
}
while (in < buf_size) {
byte = buf[in++];
diff = (byte & 0xFC) << 8;
if ((byte & 0x03) == 3)
shift[channel_number]++;
else
shift[channel_number] -= (2 * (byte & 3));
/* saturate the shifter to a lower limit of 0 */
if (shift[channel_number] < 0)
shift[channel_number] = 0;
diff >>= shift[channel_number];
predictor[channel_number] += diff;
predictor[channel_number] = av_clip_int16(predictor[channel_number]);
output_samples[out++] = predictor[channel_number];
/* toggle channel */
channel_number ^= s->channels - 1;
}
break;
case CODEC_ID_SOL_DPCM:
in = 0;
if (avctx->codec_tag != 3) {
if(*data_size/4 < buf_size)
return -1;
while (in < buf_size) {
int n1, n2;
n1 = (buf[in] >> 4) & 0xF;
n2 = buf[in++] & 0xF;
s->sample[0] += s->sol_table[n1];
if (s->sample[0] < 0) s->sample[0] = 0;
if (s->sample[0] > 255) s->sample[0] = 255;
output_samples[out++] = (s->sample[0] - 128) << 8;
s->sample[s->channels - 1] += s->sol_table[n2];
if (s->sample[s->channels - 1] < 0) s->sample[s->channels - 1] = 0;
if (s->sample[s->channels - 1] > 255) s->sample[s->channels - 1] = 255;
output_samples[out++] = (s->sample[s->channels - 1] - 128) << 8;
}
} else {
while (in < buf_size) {
int n;
n = buf[in++];
if (n & 0x80) s->sample[channel_number] -= s->sol_table[n & 0x7F];
else s->sample[channel_number] += s->sol_table[n & 0x7F];
s->sample[channel_number] = av_clip_int16(s->sample[channel_number]);
output_samples[out++] = s->sample[channel_number];
/* toggle channel */
channel_number ^= s->channels - 1;
}
}
break;
}
*data_size = out * sizeof(short);
return buf_size;
}
#define DPCM_DECODER(id, name, long_name_) \
AVCodec name ## _decoder = { \
#name, \
AVMEDIA_TYPE_AUDIO, \
id, \
sizeof(DPCMContext), \
dpcm_decode_init, \
NULL, \
NULL, \
dpcm_decode_frame, \
.long_name = NULL_IF_CONFIG_SMALL(long_name_), \
};
DPCM_DECODER(CODEC_ID_INTERPLAY_DPCM, interplay_dpcm, "DPCM Interplay");
DPCM_DECODER(CODEC_ID_ROQ_DPCM, roq_dpcm, "DPCM id RoQ");
DPCM_DECODER(CODEC_ID_SOL_DPCM, sol_dpcm, "DPCM Sol");
DPCM_DECODER(CODEC_ID_XAN_DPCM, xan_dpcm, "DPCM Xan");
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