move adx.c to adxdec.c

Originally committed as revision 10904 to svn://svn.ffmpeg.org/ffmpeg/trunk

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,
+};
+