ffmpeg/libavcodec/libac3/downmix.c

534 lines
14 KiB
C

/*
*
* downmix.c
*
* Copyright (C) Aaron Holtzman - Sept 1999
*
* Originally based on code by Yuqing Deng.
*
* This file is part of ac3dec, a free Dolby AC-3 stream decoder.
*
* ac3dec is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* ac3dec 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GNU Make; see the file COPYING. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*
*
*/
#include <inttypes.h>
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <string.h>
#include "ac3.h"
#include "ac3_internal.h"
#define CONVERT(acmod,output) (((output) << 3) + (acmod))
int downmix_init (int input, int flags, float * level, float clev, float slev)
{
static uint8_t table[11][8] = {
{AC3_CHANNEL, AC3_DOLBY, AC3_STEREO, AC3_STEREO,
AC3_STEREO, AC3_STEREO, AC3_STEREO, AC3_STEREO},
{AC3_MONO, AC3_MONO, AC3_MONO, AC3_MONO,
AC3_MONO, AC3_MONO, AC3_MONO, AC3_MONO},
{AC3_CHANNEL, AC3_DOLBY, AC3_STEREO, AC3_STEREO,
AC3_STEREO, AC3_STEREO, AC3_STEREO, AC3_STEREO},
{AC3_CHANNEL, AC3_DOLBY, AC3_STEREO, AC3_3F,
AC3_STEREO, AC3_3F, AC3_STEREO, AC3_3F},
{AC3_CHANNEL, AC3_DOLBY, AC3_STEREO, AC3_STEREO,
AC3_2F1R, AC3_2F1R, AC3_2F1R, AC3_2F1R},
{AC3_CHANNEL, AC3_DOLBY, AC3_STEREO, AC3_STEREO,
AC3_2F1R, AC3_3F1R, AC3_2F1R, AC3_3F1R},
{AC3_CHANNEL, AC3_DOLBY, AC3_STEREO, AC3_3F,
AC3_2F2R, AC3_2F2R, AC3_2F2R, AC3_2F2R},
{AC3_CHANNEL, AC3_DOLBY, AC3_STEREO, AC3_3F,
AC3_2F2R, AC3_3F2R, AC3_2F2R, AC3_3F2R},
{AC3_CHANNEL1, AC3_MONO, AC3_MONO, AC3_MONO,
AC3_MONO, AC3_MONO, AC3_MONO, AC3_MONO},
{AC3_CHANNEL2, AC3_MONO, AC3_MONO, AC3_MONO,
AC3_MONO, AC3_MONO, AC3_MONO, AC3_MONO},
{AC3_CHANNEL, AC3_DOLBY, AC3_STEREO, AC3_DOLBY,
AC3_DOLBY, AC3_DOLBY, AC3_DOLBY, AC3_DOLBY}
};
int output;
output = flags & AC3_CHANNEL_MASK;
if (output > AC3_DOLBY)
return -1;
output = table[output][input & 7];
if ((output == AC3_STEREO) &&
((input == AC3_DOLBY) || ((input == AC3_3F) && (clev == LEVEL_3DB))))
output = AC3_DOLBY;
if (flags & AC3_ADJUST_LEVEL)
switch (CONVERT (input & 7, output)) {
case CONVERT (AC3_3F, AC3_MONO):
*level *= LEVEL_3DB / (1 + clev);
break;
case CONVERT (AC3_STEREO, AC3_MONO):
case CONVERT (AC3_2F2R, AC3_2F1R):
case CONVERT (AC3_3F2R, AC3_3F1R):
level_3db:
*level *= LEVEL_3DB;
break;
case CONVERT (AC3_3F2R, AC3_2F1R):
if (clev < LEVEL_PLUS3DB - 1)
goto level_3db;
// break thru
case CONVERT (AC3_3F, AC3_STEREO):
case CONVERT (AC3_3F1R, AC3_2F1R):
case CONVERT (AC3_3F1R, AC3_2F2R):
case CONVERT (AC3_3F2R, AC3_2F2R):
*level /= 1 + clev;
break;
case CONVERT (AC3_2F1R, AC3_MONO):
*level *= LEVEL_PLUS3DB / (2 + slev);
break;
case CONVERT (AC3_2F1R, AC3_STEREO):
case CONVERT (AC3_3F1R, AC3_3F):
*level /= 1 + slev * LEVEL_3DB;
break;
case CONVERT (AC3_3F1R, AC3_MONO):
*level *= LEVEL_3DB / (1 + clev + 0.5 * slev);
break;
case CONVERT (AC3_3F1R, AC3_STEREO):
*level /= 1 + clev + slev * LEVEL_3DB;
break;
case CONVERT (AC3_2F2R, AC3_MONO):
*level *= LEVEL_3DB / (1 + slev);
break;
case CONVERT (AC3_2F2R, AC3_STEREO):
case CONVERT (AC3_3F2R, AC3_3F):
*level /= (1 + slev);
break;
case CONVERT (AC3_3F2R, AC3_MONO):
*level *= LEVEL_3DB / (1 + clev + slev);
break;
case CONVERT (AC3_3F2R, AC3_STEREO):
*level /= 1 + clev + slev;
break;
case CONVERT (AC3_MONO, AC3_DOLBY):
*level *= LEVEL_PLUS3DB;
break;
case CONVERT (AC3_3F, AC3_DOLBY):
case CONVERT (AC3_2F1R, AC3_DOLBY):
*level *= 1 / (1 + LEVEL_3DB);
break;
case CONVERT (AC3_3F1R, AC3_DOLBY):
case CONVERT (AC3_2F2R, AC3_DOLBY):
*level *= 1 / (1 + 2 * LEVEL_3DB);
break;
case CONVERT (AC3_3F2R, AC3_DOLBY):
*level *= 1 / (1 + 3 * LEVEL_3DB);
break;
}
return output;
}
static void mix1to1 (float * samples, float level, float bias)
{
int i;
for (i = 0; i < 256; i++)
samples[i] = samples[i] * level + bias;
}
static void move1to1 (float * src, float * dest, float level, float bias)
{
int i;
for (i = 0; i < 256; i++)
dest[i] = src[i] * level + bias;
}
static void mix2to1 (float * samples, float level, float bias)
{
int i;
for (i = 0; i < 256; i++)
samples[i] = (samples[i] + samples[i + 256]) * level + bias;
}
static void move2to1 (float * src, float * dest, float level, float bias)
{
int i;
for (i = 0; i < 256; i++)
dest[i] = (src[i] + src[i + 256]) * level + bias;
}
static void mix3to1 (float * samples, float level, float clev, float bias)
{
int i;
for (i = 0; i < 256; i++)
samples[i] = ((samples[i] + samples[i + 512]) * level +
samples[i + 256] * clev + bias);
}
static void mix21to1 (float * samples, float level, float slev, float bias)
{
int i;
for (i = 0; i < 256; i++)
samples[i] = ((samples[i] + samples[i + 256]) * level +
samples[i + 512] * slev + bias);
}
static void mix31to1 (float * samples, float level, float clev, float slev,
float bias)
{
int i;
for (i = 0; i < 256; i++)
samples[i] = ((samples[i] + samples[i + 512]) * level +
samples[i + 256] * clev + samples[i + 768] * slev +
bias);
}
static void mix22to1 (float * samples, float level, float slev, float bias)
{
int i;
for (i = 0; i < 256; i++)
samples[i] = ((samples[i] + samples[i + 256]) * level +
(samples[i + 512] + samples[i + 768]) * slev + bias);
}
static void mix32to1 (float * samples, float level, float clev, float slev,
float bias)
{
int i;
for (i = 0; i < 256; i++)
samples[i] = ((samples[i] + samples[i + 512]) * level +
samples[i + 256] * clev +
(samples[i + 768] + samples[i + 1024]) * slev + bias);
}
static void mix1to2 (float * src, float * dest, float level, float bias)
{
int i;
for (i = 0; i < 256; i++)
dest[i] = src[i] = src[i] * level + bias;
}
static void mix3to2 (float * samples, float level, float clev, float bias)
{
int i;
float common;
for (i = 0; i < 256; i++) {
common = samples[i + 256] * clev + bias;
samples[i] = samples[i] * level + common;
samples[i + 256] = samples[i + 512] * level + common;
}
}
static void mix21to2 (float * left, float * right, float level, float slev,
float bias)
{
int i;
float common;
for (i = 0; i < 256; i++) {
common = right[i + 256] * slev + bias;
left[i] = left[i] * level + common;
right[i] = right[i] * level + common;
}
}
static void mix11to1 (float * front, float * rear, float level, float slev,
float bias)
{
int i;
for (i = 0; i < 256; i++)
front[i] = front[i] * level + rear[i] * slev + bias;
}
static void mix31to2 (float * samples, float level, float clev, float slev,
float bias)
{
int i;
float common;
for (i = 0; i < 256; i++) {
common = samples[i + 256] * clev + samples[i + 768] * slev + bias;
samples[i] = samples[i] * level + common;
samples[i + 256] = samples[i + 512] * level + common;
}
}
static void mix32to2 (float * samples, float level, float clev, float slev,
float bias)
{
int i;
float common;
for (i = 0; i < 256; i++) {
common = samples[i + 256] * clev + bias;
samples[i] = samples[i] * level + common + samples[i + 768] * slev;
samples[i + 256] = (samples[i + 512] * level + common +
samples[i + 1024] * slev);
}
}
static void mix21toS (float * samples, float level, float level3db, float bias)
{
int i;
float surround;
for (i = 0; i < 256; i++) {
surround = samples[i + 512] * level3db;
samples[i] = samples[i] * level - surround + bias;
samples[i + 256] = samples[i + 256] * level + surround + bias;
}
}
static void mix22toS (float * samples, float level, float level3db, float bias)
{
int i;
float surround;
for (i = 0; i < 256; i++) {
surround = (samples[i + 512] + samples[i + 768]) * level3db;
samples[i] = samples[i] * level - surround + bias;
samples[i + 256] = samples[i + 256] * level + surround + bias;
}
}
static void mix31toS (float * samples, float level, float level3db, float bias)
{
int i;
float common, surround;
for (i = 0; i < 256; i++) {
common = samples[i + 256] * level3db + bias;
surround = samples[i + 768] * level3db;
samples[i] = samples[i] * level + common - surround;
samples[i + 256] = samples[i + 512] * level + common + surround;
}
}
static void mix32toS (float * samples, float level, float level3db, float bias)
{
int i;
float common, surround;
for (i = 0; i < 256; i++) {
common = samples[i + 256] * level3db + bias;
surround = (samples[i + 768] + samples[i + 1024]) * level3db;
samples[i] = samples[i] * level + common - surround;
samples[i + 256] = samples[i + 512] * level + common + surround;
}
}
void downmix (float * samples, int acmod, int output, float level, float bias,
float clev, float slev)
{
switch (CONVERT (acmod, output & AC3_CHANNEL_MASK)) {
case CONVERT (AC3_3F2R, AC3_3F2R):
mix1to1 (samples + 1024, level, bias);
case CONVERT (AC3_3F1R, AC3_3F1R):
case CONVERT (AC3_2F2R, AC3_2F2R):
mix1to1 (samples + 768, level, bias);
case CONVERT (AC3_3F, AC3_3F):
case CONVERT (AC3_2F1R, AC3_2F1R):
mix_3to3:
mix1to1 (samples + 512, level, bias);
case CONVERT (AC3_CHANNEL, AC3_CHANNEL):
case CONVERT (AC3_STEREO, AC3_STEREO):
case CONVERT (AC3_STEREO, AC3_DOLBY):
mix_2to2:
mix1to1 (samples + 256, level, bias);
case CONVERT (AC3_CHANNEL, AC3_CHANNEL1):
case CONVERT (AC3_MONO, AC3_MONO):
mix1to1 (samples, level, bias);
break;
case CONVERT (AC3_CHANNEL, AC3_CHANNEL2):
mix_1to1_b:
mix1to1 (samples + 256, level, bias);
break;
case CONVERT (AC3_STEREO, AC3_MONO):
mix_2to1:
mix2to1 (samples, level * LEVEL_3DB, bias);
break;
case CONVERT (AC3_2F1R, AC3_MONO):
if (slev == 0)
goto mix_2to1;
mix21to1 (samples, level * LEVEL_3DB, level * slev * LEVEL_3DB, bias);
break;
case CONVERT (AC3_2F2R, AC3_MONO):
if (slev == 0)
goto mix_2to1;
mix22to1 (samples, level * LEVEL_3DB, level * slev * LEVEL_3DB, bias);
break;
case CONVERT (AC3_3F, AC3_MONO):
mix_3to1:
mix3to1 (samples, level * LEVEL_3DB, level * clev * LEVEL_PLUS3DB,
bias);
break;
case CONVERT (AC3_3F1R, AC3_MONO):
if (slev == 0)
goto mix_3to1;
mix31to1 (samples, level * LEVEL_3DB, level * clev * LEVEL_PLUS3DB,
level * slev * LEVEL_3DB, bias);
break;
case CONVERT (AC3_3F2R, AC3_MONO):
if (slev == 0)
goto mix_3to1;
mix32to1 (samples, level * LEVEL_3DB, level * clev * LEVEL_PLUS3DB,
level * slev * LEVEL_3DB, bias);
break;
case CONVERT (AC3_CHANNEL, AC3_MONO):
mix2to1 (samples, level * LEVEL_6DB, bias);
break;
case CONVERT (AC3_MONO, AC3_DOLBY):
mix1to2 (samples, samples + 256, level * LEVEL_3DB, bias);
break;
case CONVERT (AC3_3F, AC3_DOLBY):
clev = LEVEL_3DB;
case CONVERT (AC3_3F, AC3_STEREO):
mix_3to2:
mix3to2 (samples, level, level * clev, bias);
break;
case CONVERT (AC3_2F1R, AC3_DOLBY):
mix21toS (samples, level, level * LEVEL_3DB, bias);
break;
case CONVERT (AC3_3F1R, AC3_DOLBY):
mix31toS (samples, level, level * LEVEL_3DB, bias);
break;
case CONVERT (AC3_2F2R, AC3_DOLBY):
mix22toS (samples, level, level * LEVEL_3DB, bias);
break;
case CONVERT (AC3_3F2R, AC3_DOLBY):
mix32toS (samples, level, level * LEVEL_3DB, bias);
break;
case CONVERT (AC3_2F1R, AC3_STEREO):
if (slev == 0)
goto mix_2to2;
mix21to2 (samples, samples + 256, level, level * slev * LEVEL_3DB,
bias);
break;
case CONVERT (AC3_3F1R, AC3_STEREO):
if (slev == 0)
goto mix_3to2;
mix31to2 (samples, level, level * clev, level * slev * LEVEL_3DB,
bias);
break;
case CONVERT (AC3_2F2R, AC3_STEREO):
if (slev == 0)
goto mix_2to2;
mix11to1 (samples, samples + 512, level, level * slev, bias);
mix11to1 (samples + 256, samples + 768, level, level * slev, bias);
break;
case CONVERT (AC3_3F2R, AC3_STEREO):
if (slev == 0)
goto mix_3to2;
mix32to2 (samples, level, level * clev, level * slev, bias);
break;
case CONVERT (AC3_3F1R, AC3_3F):
if (slev == 0)
goto mix_3to3;
mix21to2 (samples, samples + 512, level, level * slev * LEVEL_3DB,
bias);
case CONVERT (AC3_3F2R, AC3_3F):
if (slev == 0)
goto mix_3to3;
mix11to1 (samples, samples + 768, level, level * slev, bias);
mix11to1 (samples + 512, samples + 1024, level, level * slev, bias);
goto mix_1to1_b;
case CONVERT (AC3_2F1R, AC3_2F2R):
mix1to2 (samples + 512, samples + 768, level * LEVEL_3DB, bias);
goto mix_2to2;
case CONVERT (AC3_3F1R, AC3_3F2R):
mix1to2 (samples + 768, samples + 1024, level * LEVEL_3DB, bias);
goto mix_3to3;
case CONVERT (AC3_2F2R, AC3_2F1R):
mix2to1 (samples + 512, level * LEVEL_3DB, bias);
goto mix_2to2;
case CONVERT (AC3_3F2R, AC3_3F1R):
mix2to1 (samples + 768, level * LEVEL_3DB, bias);
goto mix_3to3;
case CONVERT (AC3_3F1R, AC3_2F2R):
mix3to2 (samples, level, level * clev, bias);
mix1to2 (samples + 768, samples + 512, level * LEVEL_3DB, bias);
break;
case CONVERT (AC3_3F1R, AC3_2F1R):
mix3to2 (samples, level, level * clev, bias);
move1to1 (samples + 768, samples + 512, level, bias);
break;
case CONVERT (AC3_3F2R, AC3_2F1R):
mix3to2 (samples, level, level * clev, bias);
move2to1 (samples + 768, samples + 512, level * LEVEL_3DB, bias);
break;
case CONVERT (AC3_3F2R, AC3_2F2R):
mix3to2 (samples, level, level * clev, bias);
move1to1 (samples + 768, samples + 512, level, bias);
move1to1 (samples + 1024, samples + 768, level, bias);
break;
}
}