[Audio] Refactor audio module, add android decoder libs.

android-specific/MP3Decoder/include/fmt123.h

@@ -0,0 +1,135 @@
+/*
+	libmpg123: MPEG Audio Decoder library
+
+	separate header just for audio format definitions not tied to
+	library code
+
+	copyright 1995-2015 by the mpg123 project
+	free software under the terms of the LGPL 2.1
+	see COPYING and AUTHORS files in distribution or http://mpg123.org
+*/
+
+#ifndef MPG123_ENC_H
+#define MPG123_ENC_H
+
+/** \file fmt123.h Audio format definitions. */
+
+/** \defgroup mpg123_enc mpg123 PCM sample encodings
+ *  These are definitions for audio formats used by libmpg123 and
+ *  libout123.
+ *
+ * @{
+ */
+
+/** An enum over all sample types possibly known to mpg123.
+ *  The values are designed as bit flags to allow bitmasking for encoding
+ *  families.
+ *  This is also why the enum is not used as type for actual encoding variables,
+ *  plain integers (at least 16 bit, 15 bit being used) cover the possible
+ *  combinations of these flags.
+ *
+ *  Note that (your build of) libmpg123 does not necessarily support all these.
+ *  Usually, you can expect the 8bit encodings and signed 16 bit.
+ *  Also 32bit float will be usual beginning with mpg123-1.7.0 .
+ *  What you should bear in mind is that (SSE, etc) optimized routines may be
+ *  absent for some formats. We do have SSE for 16, 32 bit and float, though.
+ *  24 bit integer is done via postprocessing of 32 bit output -- just cutting
+ *  the last byte, no rounding, even. If you want better, do it yourself.
+ *
+ *  All formats are in native byte order. If you need different endinaness, you
+ *  can simply postprocess the output buffers (libmpg123 wouldn't do anything
+ * else). The macro MPG123_SAMPLESIZE() can be helpful there.
+ */
+enum mpg123_enc_enum
+{
+/* 0000 0000 0000 1111 Some 8 bit  integer encoding. */
+	MPG123_ENC_8      = 0x00f
+/* 0000 0000 0100 0000 Some 16 bit integer encoding. */
+,	MPG123_ENC_16     = 0x040
+/* 0100 0000 0000 0000 Some 24 bit integer encoding. */
+,	MPG123_ENC_24     = 0x4000 
+/* 0000 0001 0000 0000 Some 32 bit integer encoding. */
+,	MPG123_ENC_32     = 0x100  
+/* 0000 0000 1000 0000 Some signed integer encoding. */
+,	MPG123_ENC_SIGNED = 0x080  
+/* 0000 1110 0000 0000 Some float encoding. */
+,	MPG123_ENC_FLOAT  = 0xe00  
+/* 0000 0000 1101 0000 signed 16 bit */
+,	MPG123_ENC_SIGNED_16   = (MPG123_ENC_16|MPG123_ENC_SIGNED|0x10)
+/* 0000 0000 0110 0000 unsigned 16 bit */
+,	MPG123_ENC_UNSIGNED_16 = (MPG123_ENC_16|0x20)
+/* 0000 0000 0000 0001 unsigned 8 bit */
+,	MPG123_ENC_UNSIGNED_8  = 0x01
+/* 0000 0000 1000 0010 signed 8 bit */
+,	MPG123_ENC_SIGNED_8    = (MPG123_ENC_SIGNED|0x02)
+/* 0000 0000 0000 0100 ulaw 8 bit */
+,	MPG123_ENC_ULAW_8      = 0x04
+/* 0000 0000 0000 1000 alaw 8 bit */
+,	MPG123_ENC_ALAW_8      = 0x08
+/* 0001 0001 1000 0000 signed 32 bit */
+,	MPG123_ENC_SIGNED_32   = MPG123_ENC_32|MPG123_ENC_SIGNED|0x1000
+/* 0010 0001 0000 0000 unsigned 32 bit */
+,	MPG123_ENC_UNSIGNED_32 = MPG123_ENC_32|0x2000
+/* 0101 0000 1000 0000 signed 24 bit */
+,	MPG123_ENC_SIGNED_24   = MPG123_ENC_24|MPG123_ENC_SIGNED|0x1000
+/* 0110 0000 0000 0000 unsigned 24 bit */
+,	MPG123_ENC_UNSIGNED_24 = MPG123_ENC_24|0x2000
+/* 0000 0010 0000 0000 32bit float */
+,	MPG123_ENC_FLOAT_32    = 0x200
+/* 0000 0100 0000 0000 64bit float */
+,	MPG123_ENC_FLOAT_64    = 0x400
+/* Any possibly known encoding from the list above. */
+,	MPG123_ENC_ANY = ( MPG123_ENC_SIGNED_16  | MPG123_ENC_UNSIGNED_16
+	                 | MPG123_ENC_UNSIGNED_8 | MPG123_ENC_SIGNED_8
+	                 | MPG123_ENC_ULAW_8     | MPG123_ENC_ALAW_8
+	                 | MPG123_ENC_SIGNED_32  | MPG123_ENC_UNSIGNED_32
+	                 | MPG123_ENC_SIGNED_24  | MPG123_ENC_UNSIGNED_24
+	                 | MPG123_ENC_FLOAT_32   | MPG123_ENC_FLOAT_64    )
+};
+
+/** Get size of one PCM sample with given encoding.
+ *  This is included both in libmpg123 and libout123. Both offer
+ *  an API function to provide the macro results from library
+ *  compile-time, not that of you application. This most likely
+ *  does not matter as I do not expect any fresh PCM sample
+ *  encoding to appear. But who knows? Perhaps the encoding type
+ *  will be abused for funny things in future, not even plain PCM.
+ *  And, by the way: Thomas really likes the ?: operator.
+ * \param enc the encoding (mpg123_enc_enum value)
+ * \return size of one sample in bytes
+ */
+#define MPG123_SAMPLESIZE(enc) ( \
+	(enc) & MPG123_ENC_8 \
+	?	1 \
+	:	( (enc) & MPG123_ENC_16 \
+		?	2 \
+		:	( (enc) & MPG123_ENC_24 \
+			?	3 \
+			:	( (  (enc) & MPG123_ENC_32 \
+				  || (enc) == MPG123_ENC_FLOAT_32 ) \
+				?	4 \
+				:	( (enc) == MPG123_ENC_FLOAT_64 \
+					?	8 \
+					:	0 \
+)	)	)	)	)
+
+/** Structure defining an audio format.
+ *  Providing the members as individual function arguments to define a certain
+ *  output format is easy enough. This struct makes is more comfortable to deal
+ *  with a list of formats.
+ *  Negative values for the members might be used to communicate use of default
+ *  values.
+ */
+struct mpg123_fmt
+{
+	long rate;    /**< sampling rate in Hz  */
+	int channels; /**< channel count */
+	/** encoding code, can be single value or bitwise or of members of
+	 *  mpg123_enc_enum */
+	int encoding;
+};
+
+/* @} */
+
+#endif
+