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mirror of https://github.com/mpv-player/mpv synced 2024-11-11 00:15:33 +01:00
mpv/adpcm.c
melanson 4bbefcad28 fixed format 0x62 ADPCM audio
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@4002 b3059339-0415-0410-9bf9-f77b7e298cf2
2002-01-06 01:56:27 +00:00

455 lines
10 KiB
C

/*
Unified ADPCM Decoder for MPlayer
This file is in charge of decoding all of the various ADPCM data
formats that various entities have created. Details about the data
formats can be found here:
http://www.pcisys.net/~melanson/codecs/
(C) 2001 Mike Melanson
*/
#include "config.h"
#include "bswap.h"
#include "adpcm.h"
#define BE_16(x) (be2me_16(*(unsigned short *)(x)))
#define BE_32(x) (be2me_32(*(unsigned int *)(x)))
#define LE_16(x) (le2me_16(*(unsigned short *)(x)))
#define LE_32(x) (le2me_32(*(unsigned int *)(x)))
// pertinent tables
static int adpcm_step[89] =
{
7, 8, 9, 10, 11, 12, 13, 14, 16, 17,
19, 21, 23, 25, 28, 31, 34, 37, 41, 45,
50, 55, 60, 66, 73, 80, 88, 97, 107, 118,
130, 143, 157, 173, 190, 209, 230, 253, 279, 307,
337, 371, 408, 449, 494, 544, 598, 658, 724, 796,
876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066,
2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358,
5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767
};
static int adpcm_index[16] =
{
-1, -1, -1, -1, 2, 4, 6, 8,
-1, -1, -1, -1, 2, 4, 6, 8
};
static int ms_adapt_table[] =
{
230, 230, 230, 230, 307, 409, 512, 614,
768, 614, 512, 409, 307, 230, 230, 230
};
static int ms_adapt_coeff1[] =
{
256, 512, 0, 192, 240, 460, 392
};
static int ms_adapt_coeff2[] =
{
0, -256, 0, 64, 0, -208, -232
};
// useful macros
// clamp a number between 0 and 88
#define CLAMP_0_TO_88(x) if (x < 0) x = 0; else if (x > 88) x = 88;
// clamp a number within a signed 16-bit range
#define CLAMP_S16(x) if (x < -32768) x = -32768; \
else if (x > 32767) x = 32767;
// clamp a number above 16
#define CLAMP_ABOVE_16(x) if (x < 16) x = 16;
// sign extend a 16-bit value
#define SE_16BIT(x) if (x & 0x8000) x -= 0x10000;
// sign extend a 4-bit value
#define SE_4BIT(x) if (x & 0x8) x -= 0x10;
void decode_nibbles(unsigned short *output,
int output_size, int channels,
int predictor_l, int index_l,
int predictor_r, int index_r)
{
int step[2];
int predictor[2];
int index[2];
int diff;
int i;
int sign;
int delta;
int channel_number = 0;
step[0] = adpcm_step[index_l];
step[1] = adpcm_step[index_r];
predictor[0] = predictor_l;
predictor[1] = predictor_r;
index[0] = index_l;
index[1] = index_r;
for (i = 0; i < output_size; i++)
{
delta = output[i];
index[channel_number] += adpcm_index[delta];
CLAMP_0_TO_88(index[channel_number]);
sign = delta & 8;
delta = delta & 7;
diff = step[channel_number] >> 3;
if (delta & 4) diff += step[channel_number];
if (delta & 2) diff += step[channel_number] >> 1;
if (delta & 1) diff += step[channel_number] >> 2;
if (sign)
predictor[channel_number] -= diff;
else
predictor[channel_number] += diff;
CLAMP_S16(predictor[channel_number]);
output[i] = predictor[channel_number];
step[channel_number] = adpcm_step[index[channel_number]];
// toggle channel
channel_number ^= channels - 1;
}
}
int ima_adpcm_decode_block(unsigned short *output, unsigned char *input,
int channels)
{
int initial_predictor_l = 0;
int initial_predictor_r = 0;
int initial_index_l = 0;
int initial_index_r = 0;
int i;
initial_predictor_l = BE_16(&input[0]);
initial_index_l = initial_predictor_l;
// mask, sign-extend, and clamp the predictor portion
initial_predictor_l &= 0xFF80;
SE_16BIT(initial_predictor_l);
CLAMP_S16(initial_predictor_l);
// mask and clamp the index portion
initial_index_l &= 0x7F;
CLAMP_0_TO_88(initial_index_l);
// handle stereo
if (channels > 1)
{
initial_predictor_r = BE_16(&input[IMA_ADPCM_BLOCK_SIZE]);
initial_index_r = initial_predictor_r;
// mask, sign-extend, and clamp the predictor portion
initial_predictor_r &= 0xFF80;
SE_16BIT(initial_predictor_r);
CLAMP_S16(initial_predictor_r);
// mask and clamp the index portion
initial_index_r &= 0x7F;
CLAMP_0_TO_88(initial_index_r);
}
// break apart all of the nibbles in the block
if (channels == 1)
for (i = 0; i < IMA_ADPCM_SAMPLES_PER_BLOCK / 2; i++)
{
output[i * 2 + 0] = input[2 + i] & 0x0F;
output[i * 2 + 1] = input[2 + i] >> 4;
}
else
for (i = 0; i < IMA_ADPCM_SAMPLES_PER_BLOCK / 2 * 2; i++)
{
output[i * 4 + 0] = input[2 + i] & 0x0F;
output[i * 4 + 1] = input[2 + IMA_ADPCM_BLOCK_SIZE + i] & 0x0F;
output[i * 4 + 2] = input[2 + i] >> 4;
output[i * 4 + 3] = input[2 + IMA_ADPCM_BLOCK_SIZE + i] >> 4;
}
decode_nibbles(output,
IMA_ADPCM_SAMPLES_PER_BLOCK * channels, channels,
initial_predictor_l, initial_index_l,
initial_predictor_r, initial_index_r);
return IMA_ADPCM_SAMPLES_PER_BLOCK * channels;
}
int ms_adpcm_decode_block(unsigned short *output, unsigned char *input,
int channels, int block_size)
{
int current_channel = 0;
int idelta[2];
int sample1[2];
int sample2[2];
int coeff1[2];
int coeff2[2];
int stream_ptr = 0;
int out_ptr = 0;
int upper_nibble = 1;
int nibble;
int snibble; // signed nibble
int predictor;
// fetch the header information, in stereo if both channels are present
coeff1[0] = ms_adapt_coeff1[input[stream_ptr]];
coeff2[0] = ms_adapt_coeff2[input[stream_ptr]];
stream_ptr++;
if (channels == 2)
{
coeff1[1] = ms_adapt_coeff1[input[stream_ptr]];
coeff2[1] = ms_adapt_coeff2[input[stream_ptr]];
stream_ptr++;
}
idelta[0] = LE_16(&input[stream_ptr]);
stream_ptr += 2;
SE_16BIT(idelta[0]);
if (channels == 2)
{
idelta[1] = LE_16(&input[stream_ptr]);
stream_ptr += 2;
SE_16BIT(idelta[1]);
}
sample1[0] = LE_16(&input[stream_ptr]);
stream_ptr += 2;
SE_16BIT(sample1[0]);
if (channels == 2)
{
sample1[1] = LE_16(&input[stream_ptr]);
stream_ptr += 2;
SE_16BIT(sample1[1]);
}
sample2[0] = LE_16(&input[stream_ptr]);
stream_ptr += 2;
SE_16BIT(sample2[0]);
if (channels == 2)
{
sample2[1] = LE_16(&input[stream_ptr]);
stream_ptr += 2;
SE_16BIT(sample2[1]);
}
while (stream_ptr < block_size)
{
// get the next nibble
if (upper_nibble)
nibble = snibble = input[stream_ptr] >> 4;
else
nibble = snibble = input[stream_ptr++] & 0x0F;
upper_nibble ^= 1;
SE_4BIT(snibble);
predictor = (
((sample1[current_channel] * coeff1[current_channel]) +
(sample2[current_channel] * coeff2[current_channel])) / 256) +
(snibble * idelta[current_channel]);
CLAMP_S16(predictor);
sample2[current_channel] = sample1[current_channel];
sample1[current_channel] = predictor;
output[out_ptr++] = predictor;
// compute the next adaptive scale factor (a.k.a. the variable idelta)
idelta[current_channel] =
(ms_adapt_table[nibble] * idelta[current_channel]) / 256;
CLAMP_ABOVE_16(idelta[current_channel]);
// toggle the channel
current_channel ^= channels - 1;
}
return (block_size - (MS_ADPCM_PREAMBLE_SIZE * channels)) * 2;
}
// note: This decoder assumes the format 0x61 data always comes in
// mono flavor
int fox61_adpcm_decode_block(unsigned short *output, unsigned char *input)
{
int i;
int predictor;
int index;
// the first predictor value goes straight to the output
predictor = output[0] = LE_16(&input[0]);
SE_16BIT(predictor);
index = input[2];
// unpack the nibbles
for (i = 4; i < FOX61_ADPCM_BLOCK_SIZE; i++)
{
output[1 + (i - 4) * 2 + 0] = (input[i] >> 4) & 0x0F;
output[1 + (i - 4) * 2 + 1] = input[i] & 0x0F;
}
decode_nibbles(&output[1], FOX61_ADPCM_SAMPLES_PER_BLOCK - 1, 1,
predictor, index,
0, 0);
return FOX61_ADPCM_SAMPLES_PER_BLOCK;
}
// note: This decoder assumes the format 0x62 data always comes in
// stereo flavor
int fox62_adpcm_decode_block(unsigned short *output, unsigned char *input)
{
int pred1;
int pred2;
int index1;
int index2;
int in_ptr = 0x10;
int out_ptr = 0;
int flag1 = 0;
int flag2 = 1;
int sum;
unsigned char last_byte = 0;
unsigned char nibble;
// ADPCM work variables
int sign;
int delta;
int step;
int diff;
pred1 = LE_16(&input[10]);
pred2 = LE_16(&input[12]);
SE_16BIT(pred1);
SE_16BIT(pred2);
sum = pred2;
index1 = input[14];
index2 = input[15];
while (in_ptr < 2048)
{
if (flag2)
{
last_byte = input[in_ptr++];
nibble = last_byte & 0x0F;
step = adpcm_step[index1];
sign = nibble & 8;
delta = nibble & 7;
diff = step >> 3;
if (delta & 4) diff += step;
if (delta & 2) diff += step >> 1;
if (delta & 1) diff += step >> 2;
if (sign)
pred1 -= diff;
else
pred1 += diff;
CLAMP_S16(pred1);
index1 += adpcm_index[nibble];
CLAMP_0_TO_88(index1);
if (flag1)
flag2 = 0;
else
{
nibble = (last_byte >> 4) & 0x0F;
step = adpcm_step[index2];
sign = nibble & 8;
delta = nibble & 7;
diff = step >> 3;
if (delta & 4) diff += step;
if (delta & 2) diff += step >> 1;
if (delta & 1) diff += step >> 2;
if (sign)
pred2 -= diff;
else
pred2 += diff;
CLAMP_S16(pred2);
index2 += adpcm_index[nibble];
CLAMP_0_TO_88(index2);
sum = (sum + pred2) / 2;
}
output[out_ptr++] = pred1 + sum;
output[out_ptr++] = pred1 - sum;
flag1 ^= 1;
if (in_ptr >= 2048)
break;
}
else
{
nibble = (last_byte >> 4) & 0x0F;
step = adpcm_step[index1];
sign = nibble & 8;
delta = nibble & 7;
diff = step >> 3;
if (delta & 4) diff += step;
if (delta & 2) diff += step >> 1;
if (delta & 1) diff += step >> 2;
if (sign)
pred1 -= diff;
else
pred1 += diff;
CLAMP_S16(pred1);
index1 += adpcm_index[nibble];
CLAMP_0_TO_88(index1);
if (flag1)
flag2 = 1;
else
{
last_byte = input[in_ptr++];
nibble = last_byte & 0x0F;
step = adpcm_step[index2];
sign = nibble & 8;
delta = nibble & 7;
diff = step >> 3;
if (delta & 4) diff += step;
if (delta & 2) diff += step >> 1;
if (delta & 1) diff += step >> 2;
if (sign)
pred2 -= diff;
else
pred2 += diff;
CLAMP_S16(pred2);
index2 += adpcm_index[nibble];
CLAMP_0_TO_88(index2);
sum = (sum + pred2) / 2;
}
output[out_ptr++] = pred1 + sum;
output[out_ptr++] = pred1 - sum;
flag1 ^= 1;
if (in_ptr >= 2048)
break;
}
}
return out_ptr;
}