split adx encoder in its own file

Originally committed as revision 10903 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/adx.h

@@ -0,0 +1,49 @@
+/*
+ * 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
+ */
+
+/**
+ * @file adx.h
+ * 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/
+ */
+
+#ifndef FFMPEG_ADX_H
+#define FFMPEG_ADX_H
+
+typedef struct {
+    int s1,s2;
+} PREV;
+
+typedef struct {
+    PREV prev[2];
+    int header_parsed;
+    unsigned char dec_temp[18*2];
+    int in_temp;
+} ADXContext;
+
+#define    BASEVOL   0x4000
+#define    SCALE1    0x7298
+#define    SCALE2    0x3350
+
+#endif /* FFMPEG_ADX_H */