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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-02 03:06:28 +02:00
FFmpeg/libavcodec/ac3dec_fixed.c
Andreas Rheinhardt 20f9727018 avcodec/codec_internal: Add FFCodec, hide internal part of AVCodec
Up until now, codec.h contains both public and private parts
of AVCodec. This exposes the internals of AVCodec to users
and leads them into the temptation of actually using them
and forces us to forward-declare structures and types that
users can't use at all.

This commit changes this by adding a new structure FFCodec to
codec_internal.h that extends AVCodec, i.e. contains the public
AVCodec as first member; the private fields of AVCodec are moved
to this structure, leaving codec.h clean.

Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-03-21 01:33:09 +01:00

188 lines
6.6 KiB
C

/*
* Copyright (c) 2012
* MIPS Technologies, Inc., California.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the MIPS Technologies, Inc., nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE MIPS TECHNOLOGIES, INC. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE MIPS TECHNOLOGIES, INC. BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* Author: Stanislav Ocovaj (socovaj@mips.com)
*
* AC3 fixed-point decoder for MIPS platforms
*
* 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
*/
#define FFT_FLOAT 0
#define USE_FIXED 1
#include "ac3dec.h"
#include "codec_internal.h"
static const int end_freq_inv_tab[8] =
{
50529027, 44278013, 39403370, 32292987, 27356480, 23729101, 20951060, 18755316
};
static void scale_coefs (
int32_t *dst,
const int32_t *src,
int dynrng,
int len)
{
int i, shift;
unsigned mul, round;
int temp, temp1, temp2, temp3, temp4, temp5, temp6, temp7;
mul = (dynrng & 0x1f) + 0x20;
shift = 4 - (sign_extend(dynrng, 9) >> 5);
if (shift > 0 ) {
round = 1 << (shift-1);
for (i=0; i<len; i+=8) {
temp = src[i] * mul;
temp1 = src[i+1] * mul;
temp = temp + round;
temp2 = src[i+2] * mul;
temp1 = temp1 + round;
dst[i] = temp >> shift;
temp3 = src[i+3] * mul;
temp2 = temp2 + round;
dst[i+1] = temp1 >> shift;
temp4 = src[i + 4] * mul;
temp3 = temp3 + round;
dst[i+2] = temp2 >> shift;
temp5 = src[i+5] * mul;
temp4 = temp4 + round;
dst[i+3] = temp3 >> shift;
temp6 = src[i+6] * mul;
dst[i+4] = temp4 >> shift;
temp5 = temp5 + round;
temp7 = src[i+7] * mul;
temp6 = temp6 + round;
dst[i+5] = temp5 >> shift;
temp7 = temp7 + round;
dst[i+6] = temp6 >> shift;
dst[i+7] = temp7 >> shift;
}
} else {
shift = -shift;
mul <<= shift;
for (i=0; i<len; i+=8) {
dst[i] = src[i ] * mul;
dst[i+1] = src[i+1] * mul;
dst[i+2] = src[i+2] * mul;
dst[i+3] = src[i+3] * mul;
dst[i+4] = src[i+4] * mul;
dst[i+5] = src[i+5] * mul;
dst[i+6] = src[i+6] * mul;
dst[i+7] = src[i+7] * mul;
}
}
}
/**
* Downmix samples from original signal to stereo or mono (this is for 16-bit samples
* and fixed point decoder - original (for 32-bit samples) is in ac3dsp.c).
*/
static void ac3_downmix_c_fixed16(int16_t **samples, int16_t **matrix,
int out_ch, int in_ch, int len)
{
int i, j;
int v0, v1;
if (out_ch == 2) {
for (i = 0; i < len; i++) {
v0 = v1 = 0;
for (j = 0; j < in_ch; j++) {
v0 += samples[j][i] * matrix[0][j];
v1 += samples[j][i] * matrix[1][j];
}
samples[0][i] = (v0+2048)>>12;
samples[1][i] = (v1+2048)>>12;
}
} else if (out_ch == 1) {
for (i = 0; i < len; i++) {
v0 = 0;
for (j = 0; j < in_ch; j++)
v0 += samples[j][i] * matrix[0][j];
samples[0][i] = (v0+2048)>>12;
}
}
}
#include "eac3dec.c"
#include "ac3dec.c"
static const AVOption options[] = {
{ "cons_noisegen", "enable consistent noise generation", OFFSET(consistent_noise_generation), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, PAR },
{ "drc_scale", "percentage of dynamic range compression to apply", OFFSET(drc_scale), AV_OPT_TYPE_FLOAT, {.dbl = 1.0}, 0.0, 6.0, PAR },
{ "heavy_compr", "enable heavy dynamic range compression", OFFSET(heavy_compression), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, PAR },
{ "downmix", "Request a specific channel layout from the decoder", OFFSET(downmix_layout), AV_OPT_TYPE_CHLAYOUT, {.str = NULL}, .flags = PAR },
{ NULL},
};
static const AVClass ac3_decoder_class = {
.class_name = "Fixed-Point AC-3 Decoder",
.item_name = av_default_item_name,
.option = options,
.version = LIBAVUTIL_VERSION_INT,
};
const FFCodec ff_ac3_fixed_decoder = {
.p.name = "ac3_fixed",
.p.long_name = NULL_IF_CONFIG_SMALL("ATSC A/52A (AC-3)"),
.p.type = AVMEDIA_TYPE_AUDIO,
.p.id = AV_CODEC_ID_AC3,
.p.priv_class = &ac3_decoder_class,
.priv_data_size = sizeof (AC3DecodeContext),
.init = ac3_decode_init,
.close = ac3_decode_end,
.decode = ac3_decode_frame,
.p.capabilities = AV_CODEC_CAP_CHANNEL_CONF |
AV_CODEC_CAP_DR1,
.p.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16P,
AV_SAMPLE_FMT_NONE },
.caps_internal = FF_CODEC_CAP_INIT_THREADSAFE | FF_CODEC_CAP_INIT_CLEANUP,
};