ffmpeg/libavcodec/ac3enc_fixed.c

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/*
* 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
* fixed-point AC-3 encoder.
*/
#define CONFIG_FFT_FLOAT 0
#undef CONFIG_AC3ENC_FLOAT
#include "internal.h"
#include "ac3enc.h"
#include "eac3enc.h"
#define AC3ENC_TYPE AC3ENC_TYPE_AC3_FIXED
#include "ac3enc_opts_template.c"
static const AVClass ac3enc_class = {
.class_name = "Fixed-Point AC-3 Encoder",
.item_name = av_default_item_name,
Merge commit '1470ce21cec5ee26e106e2a884c26bbf84e5aaea' * commit '1470ce21cec5ee26e106e2a884c26bbf84e5aaea': Bump libavcodec and libavformat minor versions for G.723.1 decoder and demuxer G.723.1 demuxer and decoder Add a shift parameter to celp_lp_synthesis_filter() libopenjpeg: K&R formatting cosmetics yadif: use emms_c() instead of inline assembly for emms invocations. ac3: don't use different names for option tables in the template file. lavfi: use const for AVFilterPad declarations in all filters. adpcm: don't duplicate identical AVSampleFmt array for each encoder. configure: cosmetics: Group test dependencies together configure: add more passthrough flags in tms470 filter configure: move flag filtering functions out of if/else blocks Conflicts: Changelog configure doc/general.texi libavcodec/Makefile libavcodec/ac3enc_fixed.c libavcodec/allcodecs.c libavcodec/eac3enc.c libavcodec/g723_1.c libavcodec/g723_1_data.h libavcodec/libopenjpegdec.c libavcodec/libopenjpegenc.c libavcodec/v210dec.h libavcodec/version.h libavfilter/af_anull.c libavfilter/asrc_anullsrc.c libavfilter/f_settb.c libavfilter/fifo.c libavfilter/split.c libavfilter/src_movie.c libavfilter/vf_aspect.c libavfilter/vf_blackframe.c libavfilter/vf_boxblur.c libavfilter/vf_copy.c libavfilter/vf_crop.c libavfilter/vf_cropdetect.c libavfilter/vf_delogo.c libavfilter/vf_drawbox.c libavfilter/vf_drawtext.c libavfilter/vf_fade.c libavfilter/vf_fieldorder.c libavfilter/vf_format.c libavfilter/vf_frei0r.c libavfilter/vf_gradfun.c libavfilter/vf_hflip.c libavfilter/vf_hqdn3d.c libavfilter/vf_libopencv.c libavfilter/vf_lut.c libavfilter/vf_null.c libavfilter/vf_overlay.c libavfilter/vf_pad.c libavfilter/vf_pixdesctest.c libavfilter/vf_scale.c libavfilter/vf_select.c libavfilter/vf_setpts.c libavfilter/vf_showinfo.c libavfilter/vf_slicify.c libavfilter/vf_transpose.c libavfilter/vf_unsharp.c libavfilter/vf_vflip.c libavfilter/vf_yadif.c libavfilter/vsrc_color.c libavfilter/vsrc_testsrc.c libavformat/Makefile libavformat/allformats.c libavformat/g723_1.c libavformat/version.h Merged-by: Michael Niedermayer <michaelni@gmx.at>
2012-07-22 20:10:41 +00:00
.option = ac3_options,
.version = LIBAVUTIL_VERSION_INT,
};
#include "ac3enc_template.c"
/**
* Finalize MDCT and free allocated memory.
*
* @param s AC-3 encoder private context
*/
av_cold void AC3_NAME(mdct_end)(AC3EncodeContext *s)
{
ff_mdct_end(&s->mdct);
}
/**
* Initialize MDCT tables.
*
* @param s AC-3 encoder private context
* @return 0 on success, negative error code on failure
*/
av_cold int AC3_NAME(mdct_init)(AC3EncodeContext *s)
{
int ret = ff_mdct_init(&s->mdct, 9, 0, -1.0);
s->mdct_window = ff_ac3_window;
return ret;
}
/*
* Apply KBD window to input samples prior to MDCT.
*/
static void apply_window(void *dsp, int16_t *output, const int16_t *input,
const int16_t *window, unsigned int len)
{
DSPContext *dsp0 = dsp;
dsp0->apply_window_int16(output, input, window, len);
}
/*
* Normalize the input samples to use the maximum available precision.
* This assumes signed 16-bit input samples.
*/
static int normalize_samples(AC3EncodeContext *s)
{
int v = s->ac3dsp.ac3_max_msb_abs_int16(s->windowed_samples, AC3_WINDOW_SIZE);
v = 14 - av_log2(v);
if (v > 0)
s->ac3dsp.ac3_lshift_int16(s->windowed_samples, AC3_WINDOW_SIZE, v);
/* +6 to right-shift from 31-bit to 25-bit */
return v + 6;
}
/*
* Scale MDCT coefficients to 25-bit signed fixed-point.
*/
static void scale_coefficients(AC3EncodeContext *s)
{
int blk, ch;
for (blk = 0; blk < s->num_blocks; blk++) {
AC3Block *block = &s->blocks[blk];
for (ch = 1; ch <= s->channels; ch++) {
s->ac3dsp.ac3_rshift_int32(block->mdct_coef[ch], AC3_MAX_COEFS,
block->coeff_shift[ch]);
}
}
}
static void sum_square_butterfly(AC3EncodeContext *s, int64_t sum[4],
const int32_t *coef0, const int32_t *coef1,
int len)
{
s->ac3dsp.sum_square_butterfly_int32(sum, coef0, coef1, len);
}
/*
* Clip MDCT coefficients to allowable range.
*/
static void clip_coefficients(DSPContext *dsp, int32_t *coef, unsigned int len)
{
dsp->vector_clip_int32(coef, coef, COEF_MIN, COEF_MAX, len);
}
/*
* Calculate a single coupling coordinate.
*/
static CoefType calc_cpl_coord(CoefSumType energy_ch, CoefSumType energy_cpl)
{
if (energy_cpl <= COEF_MAX) {
return 1048576;
} else {
uint64_t coord = energy_ch / (energy_cpl >> 24);
uint32_t coord32 = FFMIN(coord, 1073741824);
coord32 = ff_sqrt(coord32) << 9;
return FFMIN(coord32, COEF_MAX);
}
}
static av_cold int ac3_fixed_encode_init(AVCodecContext *avctx)
{
AC3EncodeContext *s = avctx->priv_data;
s->fixed_point = 1;
return ff_ac3_encode_init(avctx);
}
AVCodec ff_ac3_fixed_encoder = {
.name = "ac3_fixed",
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_AC3,
.priv_data_size = sizeof(AC3EncodeContext),
.init = ac3_fixed_encode_init,
.encode2 = ff_ac3_fixed_encode_frame,
.close = ff_ac3_encode_close,
2012-08-25 17:11:10 +00:00
.sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16P,
AV_SAMPLE_FMT_NONE },
.long_name = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"),
.priv_class = &ac3enc_class,
.channel_layouts = ff_ac3_channel_layouts,
.defaults = ac3_defaults,
};