216 lines
6.7 KiB
C
Executable File
216 lines
6.7 KiB
C
Executable File
/*
|
|
* Copyright (C) 2008 Jaikrishnan Menon
|
|
* Copyright (C) 2011 Stefano Sabatini
|
|
*
|
|
* 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
|
|
* 8svx audio decoder
|
|
* @author Jaikrishnan Menon
|
|
*
|
|
* supports: fibonacci delta encoding
|
|
* : exponential encoding
|
|
*
|
|
* For more information about the 8SVX format:
|
|
* http://netghost.narod.ru/gff/vendspec/iff/iff.txt
|
|
* http://sox.sourceforge.net/AudioFormats-11.html
|
|
* http://aminet.net/package/mus/misc/wavepak
|
|
* http://amigan.1emu.net/reg/8SVX.txt
|
|
*
|
|
* Samples can be found here:
|
|
* http://aminet.net/mods/smpl/
|
|
*/
|
|
|
|
#include "libavutil/avassert.h"
|
|
#include "avcodec.h"
|
|
#include "internal.h"
|
|
#include "libavutil/common.h"
|
|
|
|
/** decoder context */
|
|
typedef struct EightSvxContext {
|
|
uint8_t fib_acc[2];
|
|
const int8_t *table;
|
|
|
|
/* buffer used to store the whole first packet.
|
|
data is only sent as one large packet */
|
|
uint8_t *data[2];
|
|
int data_size;
|
|
int data_idx;
|
|
} EightSvxContext;
|
|
|
|
static const int8_t fibonacci[16] = { -34, -21, -13, -8, -5, -3, -2, -1, 0, 1, 2, 3, 5, 8, 13, 21 };
|
|
static const int8_t exponential[16] = { -128, -64, -32, -16, -8, -4, -2, -1, 0, 1, 2, 4, 8, 16, 32, 64 };
|
|
|
|
#define MAX_FRAME_SIZE 2048
|
|
|
|
/**
|
|
* Delta decode the compressed values in src, and put the resulting
|
|
* decoded samples in dst.
|
|
*
|
|
* @param[in,out] state starting value. it is saved for use in the next call.
|
|
* @param table delta sequence table
|
|
*/
|
|
static void delta_decode(uint8_t *dst, const uint8_t *src, int src_size,
|
|
uint8_t *state, const int8_t *table)
|
|
{
|
|
uint8_t val = *state;
|
|
|
|
while (src_size--) {
|
|
uint8_t d = *src++;
|
|
val = av_clip_uint8(val + table[d & 0xF]);
|
|
*dst++ = val;
|
|
val = av_clip_uint8(val + table[d >> 4]);
|
|
*dst++ = val;
|
|
}
|
|
|
|
*state = val;
|
|
}
|
|
|
|
/** decode a frame */
|
|
static int eightsvx_decode_frame(AVCodecContext *avctx, void *data,
|
|
int *got_frame_ptr, AVPacket *avpkt)
|
|
{
|
|
EightSvxContext *esc = avctx->priv_data;
|
|
AVFrame *frame = data;
|
|
int buf_size;
|
|
int ch, ret;
|
|
int hdr_size = 2;
|
|
|
|
/* decode and interleave the first packet */
|
|
if (!esc->data[0] && avpkt) {
|
|
int chan_size = avpkt->size / avctx->channels - hdr_size;
|
|
|
|
if (avpkt->size % avctx->channels) {
|
|
av_log(avctx, AV_LOG_WARNING, "Packet with odd size, ignoring last byte\n");
|
|
}
|
|
if (avpkt->size < (hdr_size + 1) * avctx->channels) {
|
|
av_log(avctx, AV_LOG_ERROR, "packet size is too small\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
esc->fib_acc[0] = avpkt->data[1] + 128;
|
|
if (avctx->channels == 2)
|
|
esc->fib_acc[1] = avpkt->data[2+chan_size+1] + 128;
|
|
|
|
esc->data_idx = 0;
|
|
esc->data_size = chan_size;
|
|
if (!(esc->data[0] = av_malloc(chan_size)))
|
|
return AVERROR(ENOMEM);
|
|
if (avctx->channels == 2) {
|
|
if (!(esc->data[1] = av_malloc(chan_size))) {
|
|
av_freep(&esc->data[0]);
|
|
return AVERROR(ENOMEM);
|
|
}
|
|
}
|
|
memcpy(esc->data[0], &avpkt->data[hdr_size], chan_size);
|
|
if (avctx->channels == 2)
|
|
memcpy(esc->data[1], &avpkt->data[2*hdr_size+chan_size], chan_size);
|
|
}
|
|
if (!esc->data[0]) {
|
|
av_log(avctx, AV_LOG_ERROR, "unexpected empty packet\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
/* decode next piece of data from the buffer */
|
|
buf_size = FFMIN(MAX_FRAME_SIZE, esc->data_size - esc->data_idx);
|
|
if (buf_size <= 0) {
|
|
*got_frame_ptr = 0;
|
|
return avpkt->size;
|
|
}
|
|
|
|
/* get output buffer */
|
|
frame->nb_samples = buf_size * 2;
|
|
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
|
|
return ret;
|
|
|
|
for (ch = 0; ch < avctx->channels; ch++) {
|
|
delta_decode(frame->data[ch], &esc->data[ch][esc->data_idx],
|
|
buf_size, &esc->fib_acc[ch], esc->table);
|
|
}
|
|
|
|
esc->data_idx += buf_size;
|
|
|
|
*got_frame_ptr = 1;
|
|
|
|
return ((avctx->frame_number == 0)*hdr_size + buf_size)*avctx->channels;
|
|
}
|
|
|
|
static av_cold int eightsvx_decode_init(AVCodecContext *avctx)
|
|
{
|
|
EightSvxContext *esc = avctx->priv_data;
|
|
|
|
if (avctx->channels < 1 || avctx->channels > 2) {
|
|
av_log(avctx, AV_LOG_ERROR, "8SVX does not support more than 2 channels\n");
|
|
return AVERROR_INVALIDDATA;
|
|
}
|
|
|
|
switch (avctx->codec->id) {
|
|
case AV_CODEC_ID_8SVX_FIB: esc->table = fibonacci; break;
|
|
case AV_CODEC_ID_8SVX_EXP: esc->table = exponential; break;
|
|
default:
|
|
av_assert1(0);
|
|
}
|
|
avctx->sample_fmt = AV_SAMPLE_FMT_U8P;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static av_cold int eightsvx_decode_close(AVCodecContext *avctx)
|
|
{
|
|
EightSvxContext *esc = avctx->priv_data;
|
|
|
|
av_freep(&esc->data[0]);
|
|
av_freep(&esc->data[1]);
|
|
esc->data_size = 0;
|
|
esc->data_idx = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
#if CONFIG_EIGHTSVX_FIB_DECODER
|
|
AVCodec ff_eightsvx_fib_decoder = {
|
|
.name = "8svx_fib",
|
|
.long_name = NULL_IF_CONFIG_SMALL("8SVX fibonacci"),
|
|
.type = AVMEDIA_TYPE_AUDIO,
|
|
.id = AV_CODEC_ID_8SVX_FIB,
|
|
.priv_data_size = sizeof (EightSvxContext),
|
|
.init = eightsvx_decode_init,
|
|
.decode = eightsvx_decode_frame,
|
|
.close = eightsvx_decode_close,
|
|
.capabilities = AV_CODEC_CAP_DR1,
|
|
.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_U8P,
|
|
AV_SAMPLE_FMT_NONE },
|
|
};
|
|
#endif
|
|
#if CONFIG_EIGHTSVX_EXP_DECODER
|
|
AVCodec ff_eightsvx_exp_decoder = {
|
|
.name = "8svx_exp",
|
|
.long_name = NULL_IF_CONFIG_SMALL("8SVX exponential"),
|
|
.type = AVMEDIA_TYPE_AUDIO,
|
|
.id = AV_CODEC_ID_8SVX_EXP,
|
|
.priv_data_size = sizeof (EightSvxContext),
|
|
.init = eightsvx_decode_init,
|
|
.decode = eightsvx_decode_frame,
|
|
.close = eightsvx_decode_close,
|
|
.capabilities = AV_CODEC_CAP_DR1,
|
|
.sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_U8P,
|
|
AV_SAMPLE_FMT_NONE },
|
|
};
|
|
#endif
|