From 76c443c6d4c6b414eea6b0826ff6a0361795234d Mon Sep 17 00:00:00 2001 From: Aurelien Jacobs Date: Thu, 1 Nov 2007 18:40:42 +0000 Subject: move adx.c to adxdec.c Originally committed as revision 10904 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/adxdec.c | 169 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 169 insertions(+) create mode 100644 libavcodec/adxdec.c (limited to 'libavcodec/adxdec.c') diff --git a/libavcodec/adxdec.c b/libavcodec/adxdec.c new file mode 100644 index 0000000000..cc7ca5ffcf --- /dev/null +++ b/libavcodec/adxdec.c @@ -0,0 +1,169 @@ +/* + * ADX ADPCM codecs + * Copyright (c) 2001,2003 BERO + * + * 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 "avcodec.h" +#include "adx.h" + +/** + * @file adx.c + * SEGA CRI adx codecs. + * + * Reference documents: + * http://ku-www.ss.titech.ac.jp/~yatsushi/adx.html + * adx2wav & wav2adx http://www.geocities.co.jp/Playtown/2004/ + */ + +/* 18 bytes <-> 32 samples */ + +static void adx_decode(short *out,const unsigned char *in,PREV *prev) +{ + int scale = AV_RB16(in); + int i; + int s0,s1,s2,d; + +// printf("%x ",scale); + + in+=2; + s1 = prev->s1; + s2 = prev->s2; + for(i=0;i<16;i++) { + d = in[i]; + // d>>=4; if (d&8) d-=16; + d = ((signed char)d >> 4); + s0 = (BASEVOL*d*scale + SCALE1*s1 - SCALE2*s2)>>14; + s2 = s1; + s1 = av_clip_int16(s0); + *out++=s1; + + d = in[i]; + //d&=15; if (d&8) d-=16; + d = ((signed char)(d<<4) >> 4); + s0 = (BASEVOL*d*scale + SCALE1*s1 - SCALE2*s2)>>14; + s2 = s1; + s1 = av_clip_int16(s0); + *out++=s1; + } + prev->s1 = s1; + prev->s2 = s2; + +} + +static void adx_decode_stereo(short *out,const unsigned char *in,PREV *prev) +{ + short tmp[32*2]; + int i; + + adx_decode(tmp ,in ,prev); + adx_decode(tmp+32,in+18,prev+1); + for(i=0;i<32;i++) { + out[i*2] = tmp[i]; + out[i*2+1] = tmp[i+32]; + } +} + +/* return data offset or 0 */ +static int adx_decode_header(AVCodecContext *avctx,const unsigned char *buf,size_t bufsize) +{ + int offset; + + if (buf[0]!=0x80) return 0; + offset = (AV_RB32(buf)^0x80000000)+4; + if (bufsizechannels = buf[7]; + avctx->sample_rate = AV_RB32(buf+8); + avctx->bit_rate = avctx->sample_rate*avctx->channels*18*8/32; + + return offset; +} + +static int adx_decode_frame(AVCodecContext *avctx, + void *data, int *data_size, + uint8_t *buf0, int buf_size) +{ + ADXContext *c = avctx->priv_data; + short *samples = data; + const uint8_t *buf = buf0; + int rest = buf_size; + + if (!c->header_parsed) { + int hdrsize = adx_decode_header(avctx,buf,rest); + if (hdrsize==0) return -1; + c->header_parsed = 1; + buf += hdrsize; + rest -= hdrsize; + } + + /* 18 bytes of data are expanded into 32*2 bytes of audio, + so guard against buffer overflows */ + if(rest/18 > *data_size/64) + rest = (*data_size/64) * 18; + + if (c->in_temp) { + int copysize = 18*avctx->channels - c->in_temp; + memcpy(c->dec_temp+c->in_temp,buf,copysize); + rest -= copysize; + buf += copysize; + if (avctx->channels==1) { + adx_decode(samples,c->dec_temp,c->prev); + samples += 32; + } else { + adx_decode_stereo(samples,c->dec_temp,c->prev); + samples += 32*2; + } + } + // + if (avctx->channels==1) { + while(rest>=18) { + adx_decode(samples,buf,c->prev); + rest-=18; + buf+=18; + samples+=32; + } + } else { + while(rest>=18*2) { + adx_decode_stereo(samples,buf,c->prev); + rest-=18*2; + buf+=18*2; + samples+=32*2; + } + } + // + c->in_temp = rest; + if (rest) { + memcpy(c->dec_temp,buf,rest); + buf+=rest; + } + *data_size = (uint8_t*)samples - (uint8_t*)data; +// printf("%d:%d ",buf-buf0,*data_size); fflush(stdout); + return buf-buf0; +} + +AVCodec adpcm_adx_decoder = { + "adpcm_adx", + CODEC_TYPE_AUDIO, + CODEC_ID_ADPCM_ADX, + sizeof(ADXContext), + NULL, + NULL, + NULL, + adx_decode_frame, +}; + -- cgit v1.2.3