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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-07 11:13:41 +02:00
FFmpeg/libavcodec/atrac.c
Michael Niedermayer c581cb4e4f Merge remote-tracking branch 'qatar/master'
* qatar/master:
  Fix even more missing includes after the common.h removal
  build: Factor out rangecoder dependencies to CONFIG_RANGECODER
  build: Factor out error resilience dependencies to CONFIG_ERROR_RESILIENCE
  x86: avcodec: Consistently name all init files
  Add more missing includes after removing the implicit common.h
  Add some more missing includes after removing the implicit common.h
  Don't include common.h from avutil.h
  rtmp: Automatically compute the hash for SWFVerification

Conflicts:
	configure
	doc/APIchanges
	doc/examples/decoding_encoding.c
	libavcodec/Makefile
	libavcodec/assdec.c
	libavcodec/audio_frame_queue.c
	libavcodec/avpacket.c
	libavcodec/dv_profile.c
	libavcodec/dwt.c
	libavcodec/libtheoraenc.c
	libavcodec/rawdec.c
	libavcodec/rv40dsp.c
	libavcodec/tiff.c
	libavcodec/tiffenc.c
	libavcodec/v210dec.h
	libavcodec/vc1dsp.c
	libavcodec/x86/Makefile
	libavfilter/asrc_anullsrc.c
	libavfilter/avfilter.c
	libavfilter/buffer.c
	libavfilter/formats.c
	libavfilter/vf_ass.c
	libavfilter/vf_drawtext.c
	libavfilter/vf_fade.c
	libavfilter/vf_select.c
	libavfilter/video.c
	libavfilter/vsrc_testsrc.c
	libavformat/version.h
	libavutil/audioconvert.c
	libavutil/error.h
	libavutil/version.h

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2012-08-16 16:20:30 +02:00

121 lines
3.1 KiB
C

/*
* Atrac common functions
* Copyright (c) 2006-2008 Maxim Poliakovski
* Copyright (c) 2006-2008 Benjamin Larsson
*
* 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
*/
#include <math.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include "avcodec.h"
#include "dsputil.h"
#include "atrac.h"
float ff_atrac_sf_table[64];
static float qmf_window[48];
static const float qmf_48tap_half[24] = {
-0.00001461907, -0.00009205479,-0.000056157569,0.00030117269,
0.0002422519, -0.00085293897,-0.0005205574, 0.0020340169,
0.00078333891, -0.0042153862, -0.00075614988, 0.0078402944,
-0.000061169922,-0.01344162, 0.0024626821, 0.021736089,
-0.007801671, -0.034090221, 0.01880949, 0.054326009,
-0.043596379, -0.099384367, 0.13207909, 0.46424159
};
/**
* Generate common tables
*/
void ff_atrac_generate_tables(void)
{
int i;
float s;
/* Generate scale factors */
if (!ff_atrac_sf_table[63])
for (i=0 ; i<64 ; i++)
ff_atrac_sf_table[i] = pow(2.0, (i - 15) / 3.0);
/* Generate the QMF window. */
if (!qmf_window[47])
for (i=0 ; i<24; i++) {
s = qmf_48tap_half[i] * 2.0;
qmf_window[i] = qmf_window[47 - i] = s;
}
}
/**
* Quadrature mirror synthesis filter.
*
* @param inlo lower part of spectrum
* @param inhi higher part of spectrum
* @param nIn size of spectrum buffer
* @param pOut out buffer
* @param delayBuf delayBuf buffer
* @param temp temp buffer
*/
void ff_atrac_iqmf (float *inlo, float *inhi, unsigned int nIn, float *pOut, float *delayBuf, float *temp)
{
int i, j;
float *p1, *p3;
memcpy(temp, delayBuf, 46*sizeof(float));
p3 = temp + 46;
/* loop1 */
for(i=0; i<nIn; i+=2){
p3[2*i+0] = inlo[i ] + inhi[i ];
p3[2*i+1] = inlo[i ] - inhi[i ];
p3[2*i+2] = inlo[i+1] + inhi[i+1];
p3[2*i+3] = inlo[i+1] - inhi[i+1];
}
/* loop2 */
p1 = temp;
for (j = nIn; j != 0; j--) {
float s1 = 0.0;
float s2 = 0.0;
for (i = 0; i < 48; i += 2) {
s1 += p1[i] * qmf_window[i];
s2 += p1[i+1] * qmf_window[i+1];
}
pOut[0] = s2;
pOut[1] = s1;
p1 += 2;
pOut += 2;
}
/* Update the delay buffer. */
memcpy(delayBuf, temp + nIn*2, 46*sizeof(float));
}