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authorAurelien Jacobs <aurel@gnuage.org>2007-11-01 18:40:42 +0000
committerAurelien Jacobs <aurel@gnuage.org>2007-11-01 18:40:42 +0000
commit76c443c6d4c6b414eea6b0826ff6a0361795234d (patch)
treec53340ccd6b2c475cdfd3588f8aedb78853f7e04 /libavcodec/adxdec.c
parentc31dea6136df692a3b0a3fcf490696b718fe9a05 (diff)
downloadffmpeg-76c443c6d4c6b414eea6b0826ff6a0361795234d.tar.gz
move adx.c to adxdec.c
Originally committed as revision 10904 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/adxdec.c')
-rw-r--r--libavcodec/adxdec.c169
1 files changed, 169 insertions, 0 deletions
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 (bufsize<offset || memcmp(buf+offset-6,"(c)CRI",6)) return 0;
+
+ avctx->channels = 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,
+};
+