mirror of https://git.ffmpeg.org/ffmpeg.git
138 lines
4.5 KiB
C
138 lines
4.5 KiB
C
/*
|
|
* Real Audio 1.0 (14.4K)
|
|
*
|
|
* Copyright (c) 2008 Vitor Sessak
|
|
* Copyright (c) 2003 Nick Kurshev
|
|
* Based on public domain decoder at http://www.honeypot.net/audio
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
#include "libavutil/channel_layout.h"
|
|
#include "avcodec.h"
|
|
#include "get_bits.h"
|
|
#include "internal.h"
|
|
#include "ra144.h"
|
|
|
|
|
|
static av_cold int ra144_decode_init(AVCodecContext * avctx)
|
|
{
|
|
RA144Context *ractx = avctx->priv_data;
|
|
|
|
ractx->avctx = avctx;
|
|
|
|
ractx->lpc_coef[0] = ractx->lpc_tables[0];
|
|
ractx->lpc_coef[1] = ractx->lpc_tables[1];
|
|
|
|
avctx->channels = 1;
|
|
avctx->channel_layout = AV_CH_LAYOUT_MONO;
|
|
avctx->sample_fmt = AV_SAMPLE_FMT_S16;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void do_output_subblock(RA144Context *ractx, const int16_t *lpc_coefs,
|
|
int gval, GetBitContext *gb)
|
|
{
|
|
int cba_idx = get_bits(gb, 7); // index of the adaptive CB, 0 if none
|
|
int gain = get_bits(gb, 8);
|
|
int cb1_idx = get_bits(gb, 7);
|
|
int cb2_idx = get_bits(gb, 7);
|
|
|
|
ff_subblock_synthesis(ractx, lpc_coefs, cba_idx, cb1_idx, cb2_idx, gval,
|
|
gain);
|
|
}
|
|
|
|
/** Uncompress one block (20 bytes -> 160*2 bytes). */
|
|
static int ra144_decode_frame(AVCodecContext * avctx, void *data,
|
|
int *got_frame_ptr, AVPacket *avpkt)
|
|
{
|
|
AVFrame *frame = data;
|
|
const uint8_t *buf = avpkt->data;
|
|
int buf_size = avpkt->size;
|
|
static const uint8_t sizes[LPC_ORDER] = {6, 5, 5, 4, 4, 3, 3, 3, 3, 2};
|
|
unsigned int refl_rms[NBLOCKS]; // RMS of the reflection coefficients
|
|
int16_t block_coefs[NBLOCKS][LPC_ORDER]; // LPC coefficients of each sub-block
|
|
unsigned int lpc_refl[LPC_ORDER]; // LPC reflection coefficients of the frame
|
|
int i, j;
|
|
int ret;
|
|
int16_t *samples;
|
|
unsigned int energy;
|
|
|
|
RA144Context *ractx = avctx->priv_data;
|
|
GetBitContext gb;
|
|
|
|
if (buf_size < FRAME_SIZE) {
|
|
av_log(avctx, AV_LOG_ERROR,
|
|
"Frame too small (%d bytes). Truncated file?\n", buf_size);
|
|
*got_frame_ptr = 0;
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
/* get output buffer */
|
|
frame->nb_samples = NBLOCKS * BLOCKSIZE;
|
|
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
|
|
return ret;
|
|
samples = (int16_t *)frame->data[0];
|
|
|
|
init_get_bits8(&gb, buf, FRAME_SIZE);
|
|
|
|
for (i = 0; i < LPC_ORDER; i++)
|
|
lpc_refl[i] = ff_lpc_refl_cb[i][get_bits(&gb, sizes[i])];
|
|
|
|
ff_eval_coefs(ractx->lpc_coef[0], lpc_refl);
|
|
ractx->lpc_refl_rms[0] = ff_rms(lpc_refl);
|
|
|
|
energy = ff_energy_tab[get_bits(&gb, 5)];
|
|
|
|
refl_rms[0] = ff_interp(ractx, block_coefs[0], 1, 1, ractx->old_energy);
|
|
refl_rms[1] = ff_interp(ractx, block_coefs[1], 2,
|
|
energy <= ractx->old_energy,
|
|
ff_t_sqrt(energy*ractx->old_energy) >> 12);
|
|
refl_rms[2] = ff_interp(ractx, block_coefs[2], 3, 0, energy);
|
|
refl_rms[3] = ff_rescale_rms(ractx->lpc_refl_rms[0], energy);
|
|
|
|
ff_int_to_int16(block_coefs[3], ractx->lpc_coef[0]);
|
|
|
|
for (i=0; i < NBLOCKS; i++) {
|
|
do_output_subblock(ractx, block_coefs[i], refl_rms[i], &gb);
|
|
|
|
for (j=0; j < BLOCKSIZE; j++)
|
|
*samples++ = av_clip_int16(ractx->curr_sblock[j + 10] << 2);
|
|
}
|
|
|
|
ractx->old_energy = energy;
|
|
ractx->lpc_refl_rms[1] = ractx->lpc_refl_rms[0];
|
|
|
|
FFSWAP(unsigned int *, ractx->lpc_coef[0], ractx->lpc_coef[1]);
|
|
|
|
*got_frame_ptr = 1;
|
|
|
|
return FRAME_SIZE;
|
|
}
|
|
|
|
AVCodec ff_ra_144_decoder = {
|
|
.name = "real_144",
|
|
.long_name = NULL_IF_CONFIG_SMALL("RealAudio 1.0 (14.4K)"),
|
|
.type = AVMEDIA_TYPE_AUDIO,
|
|
.id = AV_CODEC_ID_RA_144,
|
|
.priv_data_size = sizeof(RA144Context),
|
|
.init = ra144_decode_init,
|
|
.decode = ra144_decode_frame,
|
|
.capabilities = CODEC_CAP_DR1,
|
|
};
|