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avcodec/alacdec: split off decorrelate_stereo and append_extra_bits as alacdsp

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Reviewed-by: Michael Niedermayer <michaelni@gmx.at>
Signed-off-by: James Almer <jamrial@gmail.com>
pull/118/merge
James Almer 9 years ago
parent 2cbaa078d1
commit b70566d6ca
4 changed files with 115 additions and 41 deletions
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  1. 2
      libavcodec/Makefile
  2. 61
      libavcodec/alac.c
  3. 60
      libavcodec/alacdsp.c
  4. 33
      libavcodec/alacdsp.h

2
libavcodec/Makefile
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@ -143,7 +143,7 @@ OBJS-$(CONFIG_AC3_ENCODER) += ac3enc_float.o ac3enc.o ac3tab.o \
ac3.o kbdwin.o
OBJS-$(CONFIG_AC3_FIXED_ENCODER) += ac3enc_fixed.o ac3enc.o ac3tab.o ac3.o
OBJS-$(CONFIG_AIC_DECODER) += aic.o
OBJS-$(CONFIG_ALAC_DECODER) += alac.o alac_data.o
OBJS-$(CONFIG_ALAC_DECODER) += alac.o alac_data.o alacdsp.o
OBJS-$(CONFIG_ALAC_ENCODER) += alacenc.o alac_data.o
OBJS-$(CONFIG_ALIAS_PIX_DECODER) += aliaspixdec.o
OBJS-$(CONFIG_ALIAS_PIX_ENCODER) += aliaspixenc.o

61
libavcodec/alac.c
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@ -57,6 +57,7 @@
#include "unary.h"
#include "mathops.h"
#include "alac_data.h"
#include "alacdsp.h"
#define ALAC_EXTRADATA_SIZE 36
@ -81,6 +82,8 @@ typedef struct ALACContext {
int direct_output;
int extra_bit_bug;
ALACDSPContext dsp;
} ALACContext;
static inline unsigned int decode_scalar(GetBitContext *gb, int k, int bps)
@ -230,35 +233,6 @@ static void lpc_prediction(int32_t *error_buffer, int32_t *buffer_out,
}
}
static void decorrelate_stereo(int32_t *buffer[2], int nb_samples,
int decorr_shift, int decorr_left_weight)
{
int i;
for (i = 0; i < nb_samples; i++) {
int32_t a, b;
a = buffer[0][i];
b = buffer[1][i];
a -= (b * decorr_left_weight) >> decorr_shift;
b += a;
buffer[0][i] = b;
buffer[1][i] = a;
}
}
static void append_extra_bits(int32_t *buffer[2], int32_t *extra_bits_buffer[2],
int extra_bits, int channels, int nb_samples)
{
int i, ch;
for (ch = 0; ch < channels; ch++)
for (i = 0; i < nb_samples; i++)
buffer[ch][i] = (buffer[ch][i] << extra_bits) | extra_bits_buffer[ch][i];
}
static int decode_element(AVCodecContext *avctx, AVFrame *frame, int ch_index,
int channels)
{
@ -389,19 +363,24 @@ static int decode_element(AVCodecContext *avctx, AVFrame *frame, int ch_index,
decorr_left_weight = 0;
}
if (alac->extra_bits && alac->extra_bit_bug) {
append_extra_bits(alac->output_samples_buffer, alac->extra_bits_buffer,
alac->extra_bits, channels, alac->nb_samples);
}
if (channels == 2) {
if (alac->extra_bits && alac->extra_bit_bug) {
alac->dsp.append_extra_bits[1](alac->output_samples_buffer, alac->extra_bits_buffer,
alac->extra_bits, channels, alac->nb_samples);
}
if (channels == 2 && decorr_left_weight) {
decorrelate_stereo(alac->output_samples_buffer, alac->nb_samples,
decorr_shift, decorr_left_weight);
}
if (decorr_left_weight) {
alac->dsp.decorrelate_stereo(alac->output_samples_buffer, alac->nb_samples,
decorr_shift, decorr_left_weight);
}
if (alac->extra_bits && !alac->extra_bit_bug) {
append_extra_bits(alac->output_samples_buffer, alac->extra_bits_buffer,
alac->extra_bits, channels, alac->nb_samples);
if (alac->extra_bits && !alac->extra_bit_bug) {
alac->dsp.append_extra_bits[1](alac->output_samples_buffer, alac->extra_bits_buffer,
alac->extra_bits, channels, alac->nb_samples);
}
} else if (alac->extra_bits) {
alac->dsp.append_extra_bits[0](alac->output_samples_buffer, alac->extra_bits_buffer,
alac->extra_bits, channels, alac->nb_samples);
}
switch(alac->sample_size) {
@ -606,6 +585,8 @@ static av_cold int alac_decode_init(AVCodecContext * avctx)
return ret;
}
ff_alacdsp_init(&alac->dsp);
return 0;
}

60
libavcodec/alacdsp.c
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@ -0,0 +1,60 @@
/*
* ALAC (Apple Lossless Audio Codec) decoder
* Copyright (c) 2005 David Hammerton
*
* 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
*/
#include "libavutil/attributes.h"
#include "alacdsp.h"
#include "config.h"
static void decorrelate_stereo(int32_t *buffer[2], int nb_samples,
int decorr_shift, int decorr_left_weight)
{
int i;
for (i = 0; i < nb_samples; i++) {
int32_t a, b;
a = buffer[0][i];
b = buffer[1][i];
a -= (b * decorr_left_weight) >> decorr_shift;
b += a;
buffer[0][i] = b;
buffer[1][i] = a;
}
}
static void append_extra_bits(int32_t *buffer[2], int32_t *extra_bits_buffer[2],
int extra_bits, int channels, int nb_samples)
{
int i, ch;
for (ch = 0; ch < channels; ch++)
for (i = 0; i < nb_samples; i++)
buffer[ch][i] = (buffer[ch][i] << extra_bits) | extra_bits_buffer[ch][i];
}
av_cold void ff_alacdsp_init(ALACDSPContext *c)
{
c->decorrelate_stereo = decorrelate_stereo;
c->append_extra_bits[0] =
c->append_extra_bits[1] = append_extra_bits;
}

33
libavcodec/alacdsp.h
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@ -0,0 +1,33 @@
/*
* 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
*/
#ifndef AVCODEC_ALACDSP_H
#define AVCODEC_ALACDSP_H
#include <stdint.h>
typedef struct ALACDSPContext {
void (*decorrelate_stereo)(int32_t *buffer[2], int nb_samples,
int decorr_shift, int decorr_left_weight);
void (*append_extra_bits[2])(int32_t *buffer[2], int32_t *extra_bits_buffer[2],
int extra_bits, int channels, int nb_samples);
} ALACDSPContext;
void ff_alacdsp_init(ALACDSPContext *c);
#endif /* AVCODEC_ALACDSP_H */
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