ABX<->WAV converter; ABX code modularized, ABX encoder added, direct WAV file io

git-svn-id: svn://svn.code.sf.net/p/sc2/code/trunk@3596 8092fc87-c524-0410-9efc-e669fe64eaf9
2011-05-04 20:19:27 +00:00
parent ede7d2a545
commit c18134d041
13 changed files with 1925 additions and 315 deletions
@@ -0,0 +1,99 @@
+/*
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program 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 General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+/* ABX format encoder/decoder */
+
+#ifndef ABX_H_INCL
+#define ABX_H_INCL
+
+#include <stdint.h>
+#include "port.h"
+
+typedef struct
+{
+	uint16_t numFrames;  // Number of frames in this file
+	uint32_t totalSize;  // Total size of uncompressed data
+	uint16_t maxBufSize; // Maximum buffer needed for decoded samples
+	uint16_t freq;       // Base sampling frequency
+} abx_FileHeader;
+
+typedef struct
+{
+	uint32_t ofs;    // File offset of frame data
+	uint16_t fsize;  // Compressed frame size (in file)
+	uint16_t usize;  // Uncompressed data size
+} abx_FrameInfo;
+
+typedef struct
+{
+	uint16_t usize;        // Uncompressed data size
+	uint16_t freq;         // Sampling frequency
+	uint8_t blockSize;     // Block size picked by encoder; power of 2 and minimum 8
+	uint8_t minSquelch;    // INFO: Minimum repeat count for squelching
+	uint16_t maxError;     // INFO: Maximum total error squared per block
+} abx_FrameHeader;
+
+#define SQLCH   0x40     // Squelch byte flag
+#define RESYNC  0x80     // Resync byte flag.
+
+#define DELTAMOD   0x30  // Delta modulation bits.
+#define DELTASHIFT 4     // Delta modulation bits.
+
+#define ONEBIT 0x10 		// One bit delta modulate
+#define TWOBIT 0x20 		// Two bit delta modulate
+#define FOURBIT 0x30		// four bit delta modulate
+
+#define MULTIPLIER 0x0F  // Bottom nibble contains multiplier value.
+#define SQUELCHCNT 0x3F  // Bits for squelching.
+
+#define ABX_DEFAULT_FREQ       11025
+#define ABX_DEFAULT_ERROR      32
+#define ABX_DEFAULT_SQUELCH    2
+#define ABX_DEFAULT_BLOCKSIZE  32
+
+typedef struct
+{
+	// read-only
+	int last_error;
+	unsigned numFrames;
+	uint16_t freq;
+
+	// internal
+	bool writing;
+	FILE *fp;
+	abx_FrameInfo *frames;
+	unsigned nextFrame;
+	unsigned maxFrames;
+	uint32_t frames_ofs;
+	uint32_t data_ofs;
+	uint32_t totalSize;
+	int maxError;
+	unsigned maxBufSize;
+	unsigned maxEncSize;
+	uint8_t *buf;
+} abx_File;
+
+bool abx_open(abx_File *abx, const char *filename);
+bool abx_create(abx_File *abx, const char *filename);
+void abx_close(abx_File *abx);
+bool abx_setSamplingRate(abx_File *abx, uint32_t freq);
+bool abx_setMaxFrames(abx_File *abx, unsigned maxFrames);
+uint32_t abx_getMaxBuffer(abx_File *abx);
+
+uint32_t abx_readFrame(abx_File *abx, void *buf, uint32_t bufsize);
+uint32_t abx_writeFrame(abx_File *abx, void *buf, uint32_t bufsize);
+
+#endif /* ABX_H_INCL */