[SCM] libav/experimental: Change the AC-3 encoder to use floating-point. 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.
siretart at users.alioth.debian.org
siretart at users.alioth.debian.org
Sun Jun 30 17:21:20 UTC 2013
The following commit has been merged in the experimental branch:
commit 6fd96d1a85f3b81a1dbf08b79ba395506471ded0
Author: Justin Ruggles <justin.ruggles at gmail.com>
Date: Tue Jan 4 11:53:44 2011 +0000
Change the AC-3 encoder to use floating-point.
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
diff --git a/Changelog b/Changelog
index 41ece6c..6a25ade 100644
--- a/Changelog
+++ b/Changelog
@@ -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:
diff --git a/configure b/configure
index d756477..949f907 100755
--- a/configure
+++ b/configure
@@ -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
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index 3d13e4a..ee16b91 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -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
diff --git a/libavcodec/ac3enc.c b/libavcodec/ac3enc.c
index ec678ee..902aabf 100644
--- a/libavcodec/ac3enc.c
+++ b/libavcodec/ac3enc.c
@@ -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);
diff --git a/libavcodec/ac3enc_fixed.c b/libavcodec/ac3enc_fixed.c
index 6505b7a..9d3b195 100644
--- a/libavcodec/ac3enc_fixed.c
+++ b/libavcodec/ac3enc_fixed.c
@@ -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),
diff --git a/libavcodec/ac3enc_float.c b/libavcodec/ac3enc_float.c
new file mode 100644
index 0000000..82d806b
--- /dev/null
+++ b/libavcodec/ac3enc_float.c
@@ -0,0 +1,117 @@
+/*
+ * The simplest AC-3 encoder
+ * Copyright (c) 2000 Fabrice Bellard
+ * Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles at gmail.com>
+ * Copyright (c) 2006-2010 Prakash Punnoor <prakash at 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,
+};
diff --git a/libavcodec/h261.h b/libavcodec/ac3enc_float.h
similarity index 56%
copy from libavcodec/h261.h
copy to libavcodec/ac3enc_float.h
index 5b60dd6..1cd3681 100644
--- a/libavcodec/h261.h
+++ b/libavcodec/ac3enc_float.h
@@ -1,7 +1,8 @@
/*
- * H261 decoder
- * Copyright (c) 2002-2004 Michael Niedermayer <michaelni at gmx.at>
- * Copyright (c) 2004 Maarten Daniels
+ * The simplest AC-3 encoder
+ * Copyright (c) 2000 Fabrice Bellard
+ * Copyright (c) 2006-2010 Justin Ruggles <justin.ruggles at gmail.com>
+ * Copyright (c) 2006-2010 Prakash Punnoor <prakash at punnoor.de>
*
* This file is part of FFmpeg.
*
@@ -22,30 +23,24 @@
/**
* @file
- * h261codec.
+ * floating-point AC-3 encoder header.
*/
-#ifndef AVCODEC_H261_H
-#define AVCODEC_H261_H
+#ifndef AVCODEC_AC3ENC_FLOAT_H
+#define AVCODEC_AC3ENC_FLOAT_H
-#include "mpegvideo.h"
+#include "fft.h"
-/**
- * H261Context
- */
-typedef struct H261Context{
- MpegEncContext s;
-
- int current_mba;
- int previous_mba;
- int mba_diff;
- int mtype;
- int current_mv_x;
- int current_mv_y;
- int gob_number;
- int gob_start_code_skipped; // 1 if gob start code is already read before gob header is read
-}H261Context;
-
-#define MB_TYPE_H261_FIL 0x800000
-
-#endif /* AVCODEC_H261_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 */
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index 5bcd912..5ba1998 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -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);
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index 8b7320f..828b07a 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -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, \
diff --git a/tests/codec-regression.sh b/tests/codec-regression.sh
index 2a2ca1c..71d50a1 100755
--- a/tests/codec-regression.sh
+++ b/tests/codec-regression.sh
@@ -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 >> $logfile
diff --git a/tests/lavf-regression.sh b/tests/lavf-regression.sh
index 218a70f..736629b 100755
--- a/tests/lavf-regression.sh
+++ b/tests/lavf-regression.sh
@@ -57,7 +57,7 @@ fi
if [ -n "$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
diff --git a/tests/ref/acodec/ac3 b/tests/ref/acodec/ac3_fixed
similarity index 100%
rename from tests/ref/acodec/ac3
rename to tests/ref/acodec/ac3_fixed
--
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