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Change the AC-3 encoder to use floating-point.

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Fixed-point AC-3 encoder renamed to ac3_fixed.
Regression test acodec-ac3 renamed to acodec-ac3_fixed.
Regression test lavf-rm changed to use ac3_fixed encoder.

Originally committed as revision 26209 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Justin Ruggles 2011-01-04 11:53:44 +00:00
parent 6780f48846
commit 6fd96d1a85
12 changed files with 186 additions and 9 deletions
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1
Changelog
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@ -70,6 +70,7 @@ version <next>:
- Windows Televison (WTV) demuxer
- FFmpeg metadata format muxer and demuxer
- SubRip (srt) subtitle decoder
- floating-point AC-3 encoder added
version 0.6:

3
configure vendored
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@ -1193,6 +1193,7 @@ aac_decoder_select="mdct rdft"
aac_encoder_select="mdct"
aac_latm_decoder_select="aac_decoder aac_latm_parser"
ac3_decoder_select="mdct ac3_parser"
ac3_encoder_select="mdct"
alac_encoder_select="lpc"
amrnb_decoder_select="lsp"
amrwb_decoder_select="lsp"
@ -1453,7 +1454,6 @@ set_ne_test_deps(){
}
test_deps _encoder _decoder \
ac3 \
adpcm_g726=g726 \
adpcm_ima_qt \
adpcm_ima_wav \
@ -1525,6 +1525,7 @@ test_deps _muxer _demuxer \
wav \
yuv4mpegpipe=yuv4mpeg \
ac3_fixed_test_deps="ac3_fixed_encoder ac3_decoder rm_muxer rm_demuxer"
mpg_test_deps="mpeg1system_muxer mpegps_demuxer"
set_ne_test_deps pixdesc

3
libavcodec/Makefile
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@ -54,7 +54,8 @@ OBJS-$(CONFIG_AAC_ENCODER) += aacenc.o aaccoder.o \
mpeg4audio.o
OBJS-$(CONFIG_AASC_DECODER) += aasc.o msrledec.o
OBJS-$(CONFIG_AC3_DECODER) += ac3dec.o ac3dec_data.o ac3.o
OBJS-$(CONFIG_AC3_ENCODER) += ac3enc_fixed.o ac3tab.o ac3.o
OBJS-$(CONFIG_AC3_ENCODER) += ac3enc_float.o ac3tab.o ac3.o
OBJS-$(CONFIG_AC3_FIXED_ENCODER) += ac3enc_fixed.o ac3tab.o ac3.o
OBJS-$(CONFIG_ALAC_DECODER) += alac.o
OBJS-$(CONFIG_ALAC_ENCODER) += alacenc.o
OBJS-$(CONFIG_ALS_DECODER) += alsdec.o bgmc.o mpeg4audio.o

11
libavcodec/ac3enc.c
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@ -37,6 +37,11 @@
#include "audioconvert.h"
#ifndef CONFIG_AC3ENC_FLOAT
#define CONFIG_AC3ENC_FLOAT 0
#endif
/** Maximum number of exponent groups. +1 for separate DC exponent. */
#define AC3_MAX_EXP_GROUPS 85
@ -44,7 +49,11 @@
#define SCALE_FLOAT(a, bits) lrintf((a) * (float)(1 << (bits)))
#if CONFIG_AC3ENC_FLOAT
#include "ac3enc_float.h"
#else
#include "ac3enc_fixed.h"
#endif
/**
@ -130,7 +139,7 @@ typedef struct AC3EncodeContext {
} AC3EncodeContext;
/* prototypes for functions in ac3enc_fixed.c */
/* prototypes for functions in ac3enc_fixed.c and ac3_float.c */
static av_cold void mdct_end(AC3MDCTContext *mdct);

5
libavcodec/ac3enc_fixed.c
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@ -26,6 +26,7 @@
* fixed-point AC-3 encoder.
*/
#undef CONFIG_AC3ENC_FLOAT
#include "ac3enc.c"
@ -413,8 +414,8 @@ int main(void)
#endif /* TEST */
AVCodec ac3_encoder = {
"ac3",
AVCodec ac3_fixed_encoder = {
"ac3_fixed",
AVMEDIA_TYPE_AUDIO,
CODEC_ID_AC3,
sizeof(AC3EncodeContext),

117
libavcodec/ac3enc_float.c Normal file
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@ -0,0 +1,117 @@
/*
* The simplest AC-3 encoder
* Copyright (c) 2000 Fabrice Bellard
* Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
* Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de>
*
* 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
* floating-point AC-3 encoder.
*/
#define CONFIG_AC3ENC_FLOAT 1
#include "ac3enc.c"
/**
* Finalize MDCT and free allocated memory.
*/
static av_cold void mdct_end(AC3MDCTContext *mdct)
{
ff_mdct_end(&mdct->fft);
av_freep(&mdct->window);
}
/**
* Initialize MDCT tables.
* @param nbits log2(MDCT size)
*/
static av_cold int mdct_init(AVCodecContext *avctx, AC3MDCTContext *mdct,
int nbits)
{
float *window;
int n, n2;
n = 1 << nbits;
n2 = n >> 1;
window = av_malloc(n2 * sizeof(*window));
if (!window) {
av_log(avctx, AV_LOG_ERROR, "Cannot allocate memory.\n");
return AVERROR(ENOMEM);
}
ff_kbd_window_init(window, 5.0, n2);
mdct->window = window;
return ff_mdct_init(&mdct->fft, nbits, 0, -2.0 / n);
}
/**
* Calculate a 512-point MDCT
* @param out 256 output frequency coefficients
* @param in 512 windowed input audio samples
*/
static void mdct512(AC3MDCTContext *mdct, float *out, float *in)
{
ff_mdct_calc(&mdct->fft, out, in);
}
/**
* Apply KBD window to input samples prior to MDCT.
*/
static void apply_window(float *output, const float *input,
const float *window, int n)
{
int i;
int n2 = n >> 1;
for (i = 0; i < n2; i++) {
output[i] = input[i] * window[i];
output[n-i-1] = input[n-i-1] * window[i];
}
}
/**
* Normalize the input samples to use the maximum available precision.
*/
static int normalize_samples(AC3EncodeContext *s)
{
/* Normalization is not needed for floating-point samples, so just return 0 */
return 0;
}
AVCodec ac3_encoder = {
"ac3",
AVMEDIA_TYPE_AUDIO,
CODEC_ID_AC3,
sizeof(AC3EncodeContext),
ac3_encode_init,
ac3_encode_frame,
ac3_encode_close,
NULL,
.sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_FLT,AV_SAMPLE_FMT_NONE},
.long_name = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"),
.channel_layouts = ac3_channel_layouts,
};

46
libavcodec/ac3enc_float.h Normal file
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@ -0,0 +1,46 @@
/*
* The simplest AC-3 encoder
* Copyright (c) 2000 Fabrice Bellard
* Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles@gmail.com>
* Copyright (c) 2006-2010 Prakash Punnoor <prakash@punnoor.de>
*
* 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
* floating-point AC-3 encoder header.
*/
#ifndef AVCODEC_AC3ENC_FLOAT_H
#define AVCODEC_AC3ENC_FLOAT_H
#include "fft.h"
typedef float SampleType;
typedef float CoefType;
#define SCALE_COEF(a) SCALE_FLOAT((a), 24)
typedef struct AC3MDCTContext {
const float *window; ///< MDCT window function
FFTContext fft; ///< FFT context for MDCT calculation
} AC3MDCTContext;
#endif /* AVCODEC_AC3ENC_FLOAT_H */

1
libavcodec/allcodecs.c
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@ -222,6 +222,7 @@ void avcodec_register_all(void)
REGISTER_ENCDEC (AAC, aac);
REGISTER_DECODER (AAC_LATM, aac_latm);
REGISTER_ENCDEC (AC3, ac3);
REGISTER_ENCODER (AC3_FIXED, ac3_fixed);
REGISTER_ENCDEC (ALAC, alac);
REGISTER_DECODER (ALS, als);
REGISTER_DECODER (AMRNB, amrnb);

2
libavcodec/avcodec.h
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@ -32,7 +32,7 @@
#include "libavutil/cpu.h"
#define LIBAVCODEC_VERSION_MAJOR 52
#define LIBAVCODEC_VERSION_MINOR 101
#define LIBAVCODEC_VERSION_MINOR 102
#define LIBAVCODEC_VERSION_MICRO 0
#define LIBAVCODEC_VERSION_INT AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \

4
tests/codec-regression.sh
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@ -269,8 +269,8 @@ do_audio_decoding
$tiny_psnr $pcm_dst $pcm_ref 2 1924 >> $logfile
fi
if [ -n "$do_ac3" ] ; then
do_audio_encoding ac3.rm "" -vn
if [ -n "$do_ac3_fixed" ] ; then
do_audio_encoding ac3.rm "" "-vn -acodec ac3_fixed"
# binaries configured with --disable-sse decode ac3 differently
#do_audio_decoding
#$tiny_psnr $pcm_dst $pcm_ref 2 1024 >> $logfile

2
tests/lavf-regression.sh
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@ -57,7 +57,7 @@ fi
if [ -n "$do_rm" ] ; then
file=${outfile}lavf.rm
do_ffmpeg $file -t 1 -qscale 10 -f image2 -vcodec pgmyuv -i $raw_src -f s16le -i $pcm_src
do_ffmpeg $file -t 1 -qscale 10 -f image2 -vcodec pgmyuv -i $raw_src -f s16le -i $pcm_src -acodec ac3_fixed
# broken
#do_ffmpeg_crc $file -i $target_path/$file
fi

0
tests/ref/acodec/ac3 → tests/ref/acodec/ac3_fixed
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