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1905 serge 1
/*
3960 Serge 2
	libmpg123: MPEG Audio Decoder library (version 1.15.4)
1905 serge 3
 
3960 Serge 4
	copyright 1995-2010 by the mpg123 project - free software under the terms of the LGPL 2.1
1905 serge 5
	see COPYING and AUTHORS files in distribution or http://mpg123.org
6
*/
7
 
8
#ifndef MPG123_LIB_H
9
#define MPG123_LIB_H
10
 
11
/** \file mpg123.h The header file for the libmpg123 MPEG Audio decoder */
12
 
3960 Serge 13
/* A macro to check at compile time which set of API functions to expect.
14
   This should be incremented at least each time a new symbol is added to the header. */
15
#define MPG123_API_VERSION 37
16
 
1905 serge 17
/* These aren't actually in use... seems to work without using libtool. */
18
#ifdef BUILD_MPG123_DLL
19
/* The dll exports. */
20
#define EXPORT __declspec(dllexport)
21
#else
22
#ifdef LINK_MPG123_DLL
23
/* The exe imports. */
24
#define EXPORT __declspec(dllimport)
25
#else
26
/* Nothing on normal/UNIX builds */
27
#define EXPORT
28
#endif
29
#endif
30
 
31
#ifndef MPG123_NO_CONFIGURE /* Enable use of this file without configure. */
32
#include 
33
#include 
34
 
3960 Serge 35
/* Simplified large file handling.
36
	I used to have a check here that prevents building for a library with conflicting large file setup
37
	(application that uses 32 bit offsets with library that uses 64 bits).
38
	While that was perfectly fine in an environment where there is one incarnation of the library,
39
	it hurt GNU/Linux and Solaris systems with multilib where the distribution fails to provide the
40
	correct header matching the 32 bit library (where large files need explicit support) or
41
	the 64 bit library (where there is no distinction).
1905 serge 42
 
3960 Serge 43
	New approach: When the app defines _FILE_OFFSET_BITS, it wants non-default large file support,
44
	and thus functions with added suffix (mpg123_open_64).
45
	Any mismatch will be caught at link time because of the _FILE_OFFSET_BITS setting used when
46
	building libmpg123. Plus, there's dual mode large file support in mpg123 since 1.12 now.
47
	Link failure is not the expected outcome of any half-sane usage anymore.
48
 
49
	More complication: What about client code defining _LARGEFILE64_SOURCE? It might want direct access to the _64 functions, along with the ones without suffix. Well, that's possible now via defining MPG123_NO_LARGENAME and MPG123_LARGESUFFIX, respectively, for disabling or enforcing the suffix names.
50
*/
51
 
52
/*
53
	Now, the renaming of large file aware functions.
54
	By default, it appends underscore _FILE_OFFSET_BITS (so, mpg123_seek_64 for mpg123_seek), if _FILE_OFFSET_BITS is defined. You can force a different suffix via MPG123_LARGESUFFIX (that must include the underscore), or you can just disable the whole mess by defining MPG123_NO_LARGENAME.
55
*/
56
#if (!defined MPG123_NO_LARGENAME) && ((defined _FILE_OFFSET_BITS) || (defined MPG123_LARGESUFFIX))
57
 
58
/* Need some trickery to concatenate the value(s) of the given macro(s). */
59
#define MPG123_MACROCAT_REALLY(a, b) a ## b
60
#define MPG123_MACROCAT(a, b) MPG123_MACROCAT_REALLY(a, b)
61
#ifndef MPG123_LARGESUFFIX
62
#define MPG123_LARGESUFFIX MPG123_MACROCAT(_, _FILE_OFFSET_BITS)
1905 serge 63
#endif
3960 Serge 64
#define MPG123_LARGENAME(func) MPG123_MACROCAT(func, MPG123_LARGESUFFIX)
1905 serge 65
 
3960 Serge 66
#define mpg123_open         MPG123_LARGENAME(mpg123_open)
67
#define mpg123_open_fd      MPG123_LARGENAME(mpg123_open_fd)
68
#define mpg123_open_handle  MPG123_LARGENAME(mpg123_open_handle)
69
#define mpg123_framebyframe_decode MPG123_LARGENAME(mpg123_framebyframe_decode)
70
#define mpg123_decode_frame MPG123_LARGENAME(mpg123_decode_frame)
71
#define mpg123_tell         MPG123_LARGENAME(mpg123_tell)
72
#define mpg123_tellframe    MPG123_LARGENAME(mpg123_tellframe)
73
#define mpg123_tell_stream  MPG123_LARGENAME(mpg123_tell_stream)
74
#define mpg123_seek         MPG123_LARGENAME(mpg123_seek)
75
#define mpg123_feedseek     MPG123_LARGENAME(mpg123_feedseek)
76
#define mpg123_seek_frame   MPG123_LARGENAME(mpg123_seek_frame)
77
#define mpg123_timeframe    MPG123_LARGENAME(mpg123_timeframe)
78
#define mpg123_index        MPG123_LARGENAME(mpg123_index)
79
#define mpg123_set_index    MPG123_LARGENAME(mpg123_set_index)
80
#define mpg123_position     MPG123_LARGENAME(mpg123_position)
81
#define mpg123_length       MPG123_LARGENAME(mpg123_length)
82
#define mpg123_set_filesize MPG123_LARGENAME(mpg123_set_filesize)
83
#define mpg123_replace_reader MPG123_LARGENAME(mpg123_replace_reader)
84
#define mpg123_replace_reader_handle MPG123_LARGENAME(mpg123_replace_reader_handle)
85
#define mpg123_framepos MPG123_LARGENAME(mpg123_framepos)
1905 serge 86
 
3960 Serge 87
#endif /* largefile hackery */
1905 serge 88
 
89
#endif /* MPG123_NO_CONFIGURE */
90
 
91
#ifdef __cplusplus
92
extern "C" {
93
#endif
94
 
95
/** \defgroup mpg123_init mpg123 library and handle setup
96
 *
97
 * Functions to initialise and shutdown the mpg123 library and handles.
98
 * The parameters of handles have workable defaults, you only have to tune them when you want to tune something;-)
99
 * Tip: Use a RVA setting...
100
 *
101
 * @{
102
 */
103
 
104
/** Opaque structure for the libmpg123 decoder handle. */
105
struct mpg123_handle_struct;
106
 
107
/** Opaque structure for the libmpg123 decoder handle.
108
 *  Most functions take a pointer to a mpg123_handle as first argument and operate on its data in an object-oriented manner.
109
 */
110
typedef struct mpg123_handle_struct mpg123_handle;
111
 
112
/** Function to initialise the mpg123 library.
113
 *	This function is not thread-safe. Call it exactly once per process, before any other (possibly threaded) work with the library.
114
 *
115
 *	\return MPG123_OK if successful, otherwise an error number.
116
 */
117
EXPORT int  mpg123_init(void);
118
 
119
/** Function to close down the mpg123 library.
120
 *	This function is not thread-safe. Call it exactly once per process, before any other (possibly threaded) work with the library. */
121
EXPORT void mpg123_exit(void);
122
 
123
/** Create a handle with optional choice of decoder (named by a string, see mpg123_decoders() or mpg123_supported_decoders()).
124
 *  and optional retrieval of an error code to feed to mpg123_plain_strerror().
125
 *  Optional means: Any of or both the parameters may be NULL.
126
 *
127
 *  \return Non-NULL pointer when successful.
128
 */
129
EXPORT mpg123_handle *mpg123_new(const char* decoder, int *error);
130
 
131
/** Delete handle, mh is either a valid mpg123 handle or NULL. */
132
EXPORT void mpg123_delete(mpg123_handle *mh);
133
 
134
/** Enumeration of the parameters types that it is possible to set/get. */
135
enum mpg123_parms
136
{
3960 Serge 137
	MPG123_VERBOSE = 0,        /**< set verbosity value for enabling messages to stderr, >= 0 makes sense (integer) */
1905 serge 138
	MPG123_FLAGS,          /**< set all flags, p.ex val = MPG123_GAPLESS|MPG123_MONO_MIX (integer) */
139
	MPG123_ADD_FLAGS,      /**< add some flags (integer) */
140
	MPG123_FORCE_RATE,     /**< when value > 0, force output rate to that value (integer) */
141
	MPG123_DOWN_SAMPLE,    /**< 0=native rate, 1=half rate, 2=quarter rate (integer) */
142
	MPG123_RVA,            /**< one of the RVA choices above (integer) */
143
	MPG123_DOWNSPEED,      /**< play a frame N times (integer) */
144
	MPG123_UPSPEED,        /**< play every Nth frame (integer) */
145
	MPG123_START_FRAME,    /**< start with this frame (skip frames before that, integer) */
146
	MPG123_DECODE_FRAMES,  /**< decode only this number of frames (integer) */
147
	MPG123_ICY_INTERVAL,   /**< stream contains ICY metadata with this interval (integer) */
148
	MPG123_OUTSCALE,       /**< the scale for output samples (amplitude - integer or float according to mpg123 output format, normally integer) */
149
	MPG123_TIMEOUT,        /**< timeout for reading from a stream (not supported on win32, integer) */
150
	MPG123_REMOVE_FLAGS,   /**< remove some flags (inverse of MPG123_ADD_FLAGS, integer) */
3960 Serge 151
	MPG123_RESYNC_LIMIT,   /**< Try resync on frame parsing for that many bytes or until end of stream (<0 ... integer). This can enlarge the limit for skipping junk on beginning, too (but not reduce it).  */
1905 serge 152
	MPG123_INDEX_SIZE      /**< Set the frame index size (if supported). Values <0 mean that the index is allowed to grow dynamically in these steps (in positive direction, of course) -- Use this when you really want a full index with every individual frame. */
153
	,MPG123_PREFRAMES /**< Decode/ignore that many frames in advance for layer 3. This is needed to fill bit reservoir after seeking, for example (but also at least one frame in advance is needed to have all "normal" data for layer 3). Give a positive integer value, please.*/
3960 Serge 154
	,MPG123_FEEDPOOL  /**< For feeder mode, keep that many buffers in a pool to avoid frequent malloc/free. The pool is allocated on mpg123_open_feed(). If you change this parameter afterwards, you can trigger growth and shrinkage during decoding. The default value could change any time. If you care about this, then set it. (integer) */
155
	,MPG123_FEEDBUFFER /**< Minimal size of one internal feeder buffer, again, the default value is subject to change. (integer) */
1905 serge 156
};
157
 
158
/** Flag bits for MPG123_FLAGS, use the usual binary or to combine. */
159
enum mpg123_param_flags
160
{
161
	 MPG123_FORCE_MONO   = 0x7  /**<     0111 Force some mono mode: This is a test bitmask for seeing if any mono forcing is active. */
162
	,MPG123_MONO_LEFT    = 0x1  /**<     0001 Force playback of left channel only.  */
163
	,MPG123_MONO_RIGHT   = 0x2  /**<     0010 Force playback of right channel only. */
164
	,MPG123_MONO_MIX     = 0x4  /**<     0100 Force playback of mixed mono.         */
165
	,MPG123_FORCE_STEREO = 0x8  /**<     1000 Force stereo output.                  */
166
	,MPG123_FORCE_8BIT   = 0x10 /**< 00010000 Force 8bit formats.                   */
167
	,MPG123_QUIET        = 0x20 /**< 00100000 Suppress any printouts (overrules verbose).                    */
168
	,MPG123_GAPLESS      = 0x40 /**< 01000000 Enable gapless decoding (default on if libmpg123 has support). */
169
	,MPG123_NO_RESYNC    = 0x80 /**< 10000000 Disable resync stream after error.                             */
170
	,MPG123_SEEKBUFFER   = 0x100 /**< 000100000000 Enable small buffer on non-seekable streams to allow some peek-ahead (for better MPEG sync). */
171
	,MPG123_FUZZY        = 0x200 /**< 001000000000 Enable fuzzy seeks (guessing byte offsets or using approximate seek points from Xing TOC) */
172
	,MPG123_FORCE_FLOAT  = 0x400 /**< 010000000000 Force floating point output (32 or 64 bits depends on mpg123 internal precision). */
173
	,MPG123_PLAIN_ID3TEXT = 0x800 /**< 100000000000 Do not translate ID3 text data to UTF-8. ID3 strings will contain the raw text data, with the first byte containing the ID3 encoding code. */
3960 Serge 174
	,MPG123_IGNORE_STREAMLENGTH = 0x1000 /**< 1000000000000 Ignore any stream length information contained in the stream, which can be contained in a 'TLEN' frame of an ID3v2 tag or a Xing tag */
175
	,MPG123_SKIP_ID3V2 = 0x2000 /**< 10 0000 0000 0000 Do not parse ID3v2 tags, just skip them. */
176
	,MPG123_IGNORE_INFOFRAME = 0x4000 /**< 100 0000 0000 0000 Do not parse the LAME/Xing info frame, treat it as normal MPEG data. */
177
	,MPG123_AUTO_RESAMPLE = 0x8000 /**< 1000 0000 0000 0000 Allow automatic internal resampling of any kind (default on if supported). Especially when going lowlevel with replacing output buffer, you might want to unset this flag. Setting MPG123_DOWNSAMPLE or MPG123_FORCE_RATE will override this. */
1905 serge 178
};
179
 
180
/** choices for MPG123_RVA */
181
enum mpg123_param_rva
182
{
183
	 MPG123_RVA_OFF   = 0 /**< RVA disabled (default).   */
184
	,MPG123_RVA_MIX   = 1 /**< Use mix/track/radio gain. */
185
	,MPG123_RVA_ALBUM = 2 /**< Use album/audiophile gain */
186
	,MPG123_RVA_MAX   = MPG123_RVA_ALBUM /**< The maximum RVA code, may increase in future. */
187
};
188
 
189
/* TODO: Assess the possibilities and troubles of changing parameters during playback. */
190
 
191
/** Set a specific parameter, for a specific mpg123_handle, using a parameter
192
 *  type key chosen from the mpg123_parms enumeration, to the specified value. */
193
EXPORT int mpg123_param(mpg123_handle *mh, enum mpg123_parms type, long value, double fvalue);
194
 
195
/** Get a specific parameter, for a specific mpg123_handle.
196
 *  See the mpg123_parms enumeration for a list of available parameters. */
197
EXPORT int mpg123_getparam(mpg123_handle *mh, enum mpg123_parms type, long *val, double *fval);
198
 
3960 Serge 199
/** Feature set available for query with mpg123_feature. */
200
enum mpg123_feature_set
201
{
202
	 MPG123_FEATURE_ABI_UTF8OPEN = 0     /**< mpg123 expects path names to be given in UTF-8 encoding instead of plain native. */
203
	,MPG123_FEATURE_OUTPUT_8BIT          /**< 8bit output   */
204
	,MPG123_FEATURE_OUTPUT_16BIT         /**< 16bit output  */
205
	,MPG123_FEATURE_OUTPUT_32BIT         /**< 32bit output  */
206
	,MPG123_FEATURE_INDEX                /**< support for building a frame index for accurate seeking */
207
	,MPG123_FEATURE_PARSE_ID3V2          /**< id3v2 parsing */
208
	,MPG123_FEATURE_DECODE_LAYER1        /**< mpeg layer-1 decoder enabled */
209
	,MPG123_FEATURE_DECODE_LAYER2        /**< mpeg layer-2 decoder enabled */
210
	,MPG123_FEATURE_DECODE_LAYER3        /**< mpeg layer-3 decoder enabled */
211
	,MPG123_FEATURE_DECODE_ACCURATE      /**< accurate decoder rounding    */
212
	,MPG123_FEATURE_DECODE_DOWNSAMPLE    /**< downsample (sample omit)     */
213
	,MPG123_FEATURE_DECODE_NTOM          /**< flexible rate decoding       */
214
	,MPG123_FEATURE_PARSE_ICY            /**< ICY support                  */
215
	,MPG123_FEATURE_TIMEOUT_READ         /**< Reader with timeout (network). */
216
};
217
 
218
/** Query libmpg123 feature, 1 for success, 0 for unimplemented functions. */
219
EXPORT int mpg123_feature(const enum mpg123_feature_set key);
220
 
1905 serge 221
/* @} */
222
 
223
 
224
/** \defgroup mpg123_error mpg123 error handling
225
 *
226
 * Functions to get text version of the error numbers and an enumeration
227
 * of the error codes returned by libmpg123.
228
 *
229
 * Most functions operating on a mpg123_handle simply return MPG123_OK on success and MPG123_ERR on failure (setting the internal error variable of the handle to the specific error code).
230
 * Decoding/seek functions may also return message codes MPG123_DONE, MPG123_NEW_FORMAT and MPG123_NEED_MORE (please read up on these on how to react!).
231
 * The positive range of return values is used for "useful" values when appropriate.
232
 *
233
 * @{
234
 */
235
 
236
/** Enumeration of the message and error codes and returned by libmpg123 functions. */
237
enum mpg123_errors
238
{
239
	MPG123_DONE=-12,	/**< Message: Track ended. Stop decoding. */
240
	MPG123_NEW_FORMAT=-11,	/**< Message: Output format will be different on next call. Note that some libmpg123 versions between 1.4.3 and 1.8.0 insist on you calling mpg123_getformat() after getting this message code. Newer verisons behave like advertised: You have the chance to call mpg123_getformat(), but you can also just continue decoding and get your data. */
241
	MPG123_NEED_MORE=-10,	/**< Message: For feed reader: "Feed me more!" (call mpg123_feed() or mpg123_decode() with some new input data). */
242
	MPG123_ERR=-1,			/**< Generic Error */
243
	MPG123_OK=0, 			/**< Success */
244
	MPG123_BAD_OUTFORMAT, 	/**< Unable to set up output format! */
245
	MPG123_BAD_CHANNEL,		/**< Invalid channel number specified. */
246
	MPG123_BAD_RATE,		/**< Invalid sample rate specified.  */
247
	MPG123_ERR_16TO8TABLE,	/**< Unable to allocate memory for 16 to 8 converter table! */
248
	MPG123_BAD_PARAM,		/**< Bad parameter id! */
249
	MPG123_BAD_BUFFER,		/**< Bad buffer given -- invalid pointer or too small size. */
250
	MPG123_OUT_OF_MEM,		/**< Out of memory -- some malloc() failed. */
251
	MPG123_NOT_INITIALIZED,	/**< You didn't initialize the library! */
252
	MPG123_BAD_DECODER,		/**< Invalid decoder choice. */
253
	MPG123_BAD_HANDLE,		/**< Invalid mpg123 handle. */
254
	MPG123_NO_BUFFERS,		/**< Unable to initialize frame buffers (out of memory?). */
255
	MPG123_BAD_RVA,			/**< Invalid RVA mode. */
256
	MPG123_NO_GAPLESS,		/**< This build doesn't support gapless decoding. */
257
	MPG123_NO_SPACE,		/**< Not enough buffer space. */
258
	MPG123_BAD_TYPES,		/**< Incompatible numeric data types. */
259
	MPG123_BAD_BAND,		/**< Bad equalizer band. */
260
	MPG123_ERR_NULL,		/**< Null pointer given where valid storage address needed. */
261
	MPG123_ERR_READER,		/**< Error reading the stream. */
262
	MPG123_NO_SEEK_FROM_END,/**< Cannot seek from end (end is not known). */
263
	MPG123_BAD_WHENCE,		/**< Invalid 'whence' for seek function.*/
264
	MPG123_NO_TIMEOUT,		/**< Build does not support stream timeouts. */
265
	MPG123_BAD_FILE,		/**< File access error. */
266
	MPG123_NO_SEEK,			/**< Seek not supported by stream. */
267
	MPG123_NO_READER,		/**< No stream opened. */
268
	MPG123_BAD_PARS,		/**< Bad parameter handle. */
3960 Serge 269
	MPG123_BAD_INDEX_PAR,	/**< Bad parameters to mpg123_index() and mpg123_set_index() */
1905 serge 270
	MPG123_OUT_OF_SYNC,	/**< Lost track in bytestream and did not try to resync. */
271
	MPG123_RESYNC_FAIL,	/**< Resync failed to find valid MPEG data. */
272
	MPG123_NO_8BIT,	/**< No 8bit encoding possible. */
273
	MPG123_BAD_ALIGN,	/**< Stack aligmnent error */
274
	MPG123_NULL_BUFFER,	/**< NULL input buffer with non-zero size... */
275
	MPG123_NO_RELSEEK,	/**< Relative seek not possible (screwed up file offset) */
276
	MPG123_NULL_POINTER, /**< You gave a null pointer somewhere where you shouldn't have. */
277
	MPG123_BAD_KEY,	/**< Bad key value given. */
278
	MPG123_NO_INDEX,	/**< No frame index in this build. */
279
	MPG123_INDEX_FAIL,	/**< Something with frame index went wrong. */
280
	MPG123_BAD_DECODER_SETUP,	/**< Something prevents a proper decoder setup */
281
	MPG123_MISSING_FEATURE  /**< This feature has not been built into libmpg123. */
282
	,MPG123_BAD_VALUE /**< A bad value has been given, somewhere. */
283
	,MPG123_LSEEK_FAILED /**< Low-level seek failed. */
3960 Serge 284
	,MPG123_BAD_CUSTOM_IO /**< Custom I/O not prepared. */
285
	,MPG123_LFS_OVERFLOW /**< Offset value overflow during translation of large file API calls -- your client program cannot handle that large file. */
286
	,MPG123_INT_OVERFLOW /**< Some integer overflow. */
1905 serge 287
};
288
 
289
/** Return a string describing that error errcode means. */
290
EXPORT const char* mpg123_plain_strerror(int errcode);
291
 
292
/** Give string describing what error has occured in the context of handle mh.
293
 *  When a function operating on an mpg123 handle returns MPG123_ERR, you should check for the actual reason via
294
 *  char *errmsg = mpg123_strerror(mh)
295
 *  This function will catch mh == NULL and return the message for MPG123_BAD_HANDLE. */
296
EXPORT const char* mpg123_strerror(mpg123_handle *mh);
297
 
298
/** Return the plain errcode intead of a string. */
299
EXPORT int mpg123_errcode(mpg123_handle *mh);
300
 
301
/*@}*/
302
 
303
 
304
/** \defgroup mpg123_decoder mpg123 decoder selection
305
 *
306
 * Functions to list and select the available decoders.
307
 * Perhaps the most prominent feature of mpg123: You have several (optimized) decoders to choose from (on x86 and PPC (MacOS) systems, that is).
308
 *
309
 * @{
310
 */
311
 
312
/** Return a NULL-terminated array of generally available decoder names (plain 8bit ASCII). */
3960 Serge 313
EXPORT const char **mpg123_decoders(void);
1905 serge 314
 
315
/** Return a NULL-terminated array of the decoders supported by the CPU (plain 8bit ASCII). */
3960 Serge 316
EXPORT const char **mpg123_supported_decoders(void);
1905 serge 317
 
318
/** Set the chosen decoder to 'decoder_name' */
319
EXPORT int mpg123_decoder(mpg123_handle *mh, const char* decoder_name);
320
 
321
/** Get the currently active decoder engine name.
322
    The active decoder engine can vary depening on output constraints,
323
    mostly non-resampling, integer output is accelerated via 3DNow & Co. but for other modes a fallback engine kicks in.
324
    Note that this can return a decoder that is ony active in the hidden and not available as decoder choice from the outside.
325
    \return The decoder name or NULL on error. */
326
EXPORT const char* mpg123_current_decoder(mpg123_handle *mh);
327
 
328
/*@}*/
329
 
330
 
331
/** \defgroup mpg123_output mpg123 output audio format
332
 *
333
 * Functions to get and select the format of the decoded audio.
334
 *
3960 Serge 335
 * Before you dive in, please be warned that you might get confused by this. This seems to happen a lot, therefore I am trying to explain in advance.
336
 *
337
 * The mpg123 library decides what output format to use when encountering the first frame in a stream, or actually any frame that is still valid but differs from the frames before in the prompted output format. At such a deciding point, an internal table of allowed encodings, sampling rates and channel setups is consulted. According to this table, an output format is chosen and the decoding engine set up accordingly (including ptimized routines for different output formats). This might seem unusual but it just follows from the non-existence of "MPEG audio files" with defined overall properties. There are streams, streams are concatenations of (semi) independent frames. We store streams on disk and call them "MPEG audio files", but that does not change their nature as the decoder is concerned (the LAME/Xing header for gapless decoding makes things interesting again).
338
 *
339
 * To get to the point: What you do with mpg123_format() and friends is to fill the internal table of allowed formats before it is used. That includes removing support for some formats or adding your forced sample rate (see MPG123_FORCE_RATE) that will be used with the crude internal resampler. Also keep in mind that the sample encoding is just a question of choice -- the MPEG frames do only indicate their native sampling rate and channel count. If you want to decode to integer or float samples, 8 or 16 bit ... that is your decision. In a "clean" world, libmpg123 would always decode to 32 bit float and let you handle any sample conversion. But there are optimized routines that work faster by directly decoding to the desired encoding / accuracy. We prefer efficiency over conceptual tidyness.
340
 *
341
 * People often start out thinking that mpg123_format() should change the actual decoding format on the fly. That is wrong. It only has effect on the next natural change of output format, when libmpg123 will consult its format table again. To make life easier, you might want to call mpg123_format_none() before any thing else and then just allow one desired encoding and a limited set of sample rates / channel choices that you actually intend to deal with. You can force libmpg123 to decode everything to 44100 KHz, stereo, 16 bit integer ... it will duplicate mono channels and even do resampling if needed (unless that feature is disabled in the build, same with some encodings). But I have to stress that the resampling of libmpg123 is very crude and doesn't even contain any kind of "proper" interpolation.
342
 *
343
 * In any case, watch out for MPG123_NEW_FORMAT as return message from decoding routines and call mpg123_getformat() to get the currently active output format.
344
 *
1905 serge 345
 * @{
346
 */
347
 
348
/** An enum over all sample types possibly known to mpg123.
349
 *  The values are designed as bit flags to allow bitmasking for encoding families.
350
 *
351
 *  Note that (your build of) libmpg123 does not necessarily support all these.
352
 *  Usually, you can expect the 8bit encodings and signed 16 bit.
353
 *  Also 32bit float will be usual beginning with mpg123-1.7.0 .
3960 Serge 354
 *  What you should bear in mind is that (SSE, etc) optimized routines may be absent
355
 *  for some formats. We do have SSE for 16, 32 bit and float, though.
356
 *  24 bit integer is done via postprocessing of 32 bit output -- just cutting
357
 *  the last byte, no rounding, even. If you want better, do it yourself.
1905 serge 358
 *
3960 Serge 359
 *  All formats are in native byte order. If you need different endinaness, you
360
 *  can simply postprocess the output buffers (libmpg123 wouldn't do anything else).
361
 *  mpg123_encsize() can be helpful there.
1905 serge 362
 */
363
enum mpg123_enc_enum
364
{
3960 Serge 365
	 MPG123_ENC_8      = 0x00f  /**<      0000 0000 1111 Some 8 bit  integer encoding. */
366
	,MPG123_ENC_16     = 0x040  /**<      0000 0100 0000 Some 16 bit integer encoding. */
367
	,MPG123_ENC_24     = 0x4000 /**< 0100 0000 0000 0000 Some 24 bit integer encoding. */
368
	,MPG123_ENC_32     = 0x100  /**<      0001 0000 0000 Some 32 bit integer encoding. */
369
	,MPG123_ENC_SIGNED = 0x080  /**<      0000 1000 0000 Some signed integer encoding. */
370
	,MPG123_ENC_FLOAT  = 0xe00  /**<      1110 0000 0000 Some float encoding. */
1905 serge 371
	,MPG123_ENC_SIGNED_16   = (MPG123_ENC_16|MPG123_ENC_SIGNED|0x10) /**<           1101 0000 signed 16 bit */
372
	,MPG123_ENC_UNSIGNED_16 = (MPG123_ENC_16|0x20)                   /**<           0110 0000 unsigned 16 bit */
373
	,MPG123_ENC_UNSIGNED_8  = 0x01                                   /**<           0000 0001 unsigned 8 bit */
374
	,MPG123_ENC_SIGNED_8    = (MPG123_ENC_SIGNED|0x02)               /**<           1000 0010 signed 8 bit */
375
	,MPG123_ENC_ULAW_8      = 0x04                                   /**<           0000 0100 ulaw 8 bit */
376
	,MPG123_ENC_ALAW_8      = 0x08                                   /**<           0000 1000 alaw 8 bit */
377
	,MPG123_ENC_SIGNED_32   = MPG123_ENC_32|MPG123_ENC_SIGNED|0x1000 /**< 0001 0001 1000 0000 signed 32 bit */
378
	,MPG123_ENC_UNSIGNED_32 = MPG123_ENC_32|0x2000                   /**< 0010 0001 0000 0000 unsigned 32 bit */
3960 Serge 379
	,MPG123_ENC_SIGNED_24   = MPG123_ENC_24|MPG123_ENC_SIGNED|0x1000 /**< 0101 0000 1000 0000 signed 24 bit */
380
	,MPG123_ENC_UNSIGNED_24 = MPG123_ENC_24|0x2000                   /**< 0110 0000 0000 0000 unsigned 24 bit */
1905 serge 381
	,MPG123_ENC_FLOAT_32    = 0x200                                  /**<      0010 0000 0000 32bit float */
382
	,MPG123_ENC_FLOAT_64    = 0x400                                  /**<      0100 0000 0000 64bit float */
383
	,MPG123_ENC_ANY = ( MPG123_ENC_SIGNED_16  | MPG123_ENC_UNSIGNED_16 | MPG123_ENC_UNSIGNED_8
384
	                  | MPG123_ENC_SIGNED_8   | MPG123_ENC_ULAW_8      | MPG123_ENC_ALAW_8
385
	                  | MPG123_ENC_SIGNED_32  | MPG123_ENC_UNSIGNED_32
3960 Serge 386
	                  | MPG123_ENC_SIGNED_24  | MPG123_ENC_UNSIGNED_24
387
	                  | MPG123_ENC_FLOAT_32   | MPG123_ENC_FLOAT_64 ) /**< Any encoding on the list. */
1905 serge 388
};
389
 
390
/** They can be combined into one number (3) to indicate mono and stereo... */
391
enum mpg123_channelcount
392
{
393
	 MPG123_MONO   = 1
394
	,MPG123_STEREO = 2
395
};
396
 
397
/** An array of supported standard sample rates
398
 *  These are possible native sample rates of MPEG audio files.
399
 *  You can still force mpg123 to resample to a different one, but by default you will only get audio in one of these samplings.
400
 *  \param list Store a pointer to the sample rates array there.
401
 *  \param number Store the number of sample rates there. */
402
EXPORT void mpg123_rates(const long **list, size_t *number);
403
 
404
/** An array of supported audio encodings.
405
 *  An audio encoding is one of the fully qualified members of mpg123_enc_enum (MPG123_ENC_SIGNED_16, not MPG123_SIGNED).
406
 *  \param list Store a pointer to the encodings array there.
407
 *  \param number Store the number of encodings there. */
408
EXPORT void mpg123_encodings(const int **list, size_t *number);
409
 
3960 Serge 410
/** Return the size (in bytes) of one mono sample of the named encoding.
411
 * \param encoding The encoding value to analyze.
412
 * \return positive size of encoding in bytes, 0 on invalid encoding. */
413
EXPORT int mpg123_encsize(int encoding);
414
 
1905 serge 415
/** Configure a mpg123 handle to accept no output format at all,
416
 *  use before specifying supported formats with mpg123_format */
417
EXPORT int mpg123_format_none(mpg123_handle *mh);
418
 
419
/** Configure mpg123 handle to accept all formats
420
 *  (also any custom rate you may set) -- this is default. */
421
EXPORT int mpg123_format_all(mpg123_handle *mh);
422
 
423
/** Set the audio format support of a mpg123_handle in detail:
424
 *  \param mh audio decoder handle
425
 *  \param rate The sample rate value (in Hertz).
426
 *  \param channels A combination of MPG123_STEREO and MPG123_MONO.
427
 *  \param encodings A combination of accepted encodings for rate and channels, p.ex MPG123_ENC_SIGNED16 | MPG123_ENC_ULAW_8 (or 0 for no support). Please note that some encodings may not be supported in the library build and thus will be ignored here.
428
 *  \return MPG123_OK on success, MPG123_ERR if there was an error. */
429
EXPORT int mpg123_format(mpg123_handle *mh, long rate, int channels, int encodings);
430
 
431
/** Check to see if a specific format at a specific rate is supported
432
 *  by mpg123_handle.
433
 *  \return 0 for no support (that includes invalid parameters), MPG123_STEREO,
434
 *          MPG123_MONO or MPG123_STEREO|MPG123_MONO. */
435
EXPORT int mpg123_format_support(mpg123_handle *mh, long rate, int encoding);
436
 
437
/** Get the current output format written to the addresses givenr. */
438
EXPORT int mpg123_getformat(mpg123_handle *mh, long *rate, int *channels, int *encoding);
439
 
440
/*@}*/
441
 
442
 
443
/** \defgroup mpg123_input mpg123 file input and decoding
444
 *
445
 * Functions for input bitstream and decoding operations.
446
 * Decoding/seek functions may also return message codes MPG123_DONE, MPG123_NEW_FORMAT and MPG123_NEED_MORE (please read up on these on how to react!).
447
 * @{
448
 */
449
 
450
/* reading samples / triggering decoding, possible return values: */
451
/** Enumeration of the error codes returned by libmpg123 functions. */
452
 
453
/** Open and prepare to decode the specified file by filesystem path.
454
 *  This does not open HTTP urls; libmpg123 contains no networking code.
455
 *  If you want to decode internet streams, use mpg123_open_fd() or mpg123_open_feed().
456
 */
457
EXPORT int mpg123_open(mpg123_handle *mh, const char *path);
458
 
459
/** Use an already opened file descriptor as the bitstream input
460
 *  mpg123_close() will _not_ close the file descriptor.
461
 */
462
EXPORT int mpg123_open_fd(mpg123_handle *mh, int fd);
463
 
3960 Serge 464
/** Use an opaque handle as bitstream input. This works only with the
465
 *  replaced I/O from mpg123_replace_reader_handle()!
466
 *  mpg123_close() will call the cleanup callback for your handle (if you gave one).
467
 */
468
EXPORT int mpg123_open_handle(mpg123_handle *mh, void *iohandle);
469
 
1905 serge 470
/** Open a new bitstream and prepare for direct feeding
471
 *  This works together with mpg123_decode(); you are responsible for reading and feeding the input bitstream.
472
 */
473
EXPORT int mpg123_open_feed(mpg123_handle *mh);
474
 
475
/** Closes the source, if libmpg123 opened it. */
476
EXPORT int mpg123_close(mpg123_handle *mh);
477
 
478
/** Read from stream and decode up to outmemsize bytes.
479
 *  \param outmemory address of output buffer to write to
480
 *  \param outmemsize maximum number of bytes to write
481
 *  \param done address to store the number of actually decoded bytes to
482
 *  \return error/message code (watch out for MPG123_DONE and friends!) */
483
EXPORT int mpg123_read(mpg123_handle *mh, unsigned char *outmemory, size_t outmemsize, size_t *done);
484
 
485
/** Feed data for a stream that has been opened with mpg123_open_feed().
486
 *  It's give and take: You provide the bytestream, mpg123 gives you the decoded samples.
487
 *  \param in input buffer
488
 *  \param size number of input bytes
489
 *  \return error/message code. */
490
EXPORT int mpg123_feed(mpg123_handle *mh, const unsigned char *in, size_t size);
491
 
492
/** Decode MPEG Audio from inmemory to outmemory.
493
 *  This is very close to a drop-in replacement for old mpglib.
494
 *  When you give zero-sized output buffer the input will be parsed until
495
 *  decoded data is available. This enables you to get MPG123_NEW_FORMAT (and query it)
496
 *  without taking decoded data.
497
 *  Think of this function being the union of mpg123_read() and mpg123_feed() (which it actually is, sort of;-).
498
 *  You can actually always decide if you want those specialized functions in separate steps or one call this one here.
499
 *  \param inmemory input buffer
500
 *  \param inmemsize number of input bytes
501
 *  \param outmemory output buffer
502
 *  \param outmemsize maximum number of output bytes
503
 *  \param done address to store the number of actually decoded bytes to
504
 *  \return error/message code (watch out especially for MPG123_NEED_MORE)
505
 */
3960 Serge 506
EXPORT int mpg123_decode(mpg123_handle *mh, const unsigned char *inmemory, size_t inmemsize, unsigned char *outmemory, size_t outmemsize, size_t *done);
1905 serge 507
 
508
/** Decode next MPEG frame to internal buffer
509
 *  or read a frame and return after setting a new format.
510
 *  \param num current frame offset gets stored there
511
 *  \param audio This pointer is set to the internal buffer to read the decoded audio from.
512
 *  \param bytes number of output bytes ready in the buffer
513
 */
514
EXPORT int mpg123_decode_frame(mpg123_handle *mh, off_t *num, unsigned char **audio, size_t *bytes);
515
 
3960 Serge 516
/** Decode current MPEG frame to internal buffer.
517
 * Warning: This is experimental API that might change in future releases!
518
 * Please watch mpg123 development closely when using it.
519
 *  \param num last frame offset gets stored there
520
 *  \param audio this pointer is set to the internal buffer to read the decoded audio from.
521
 *  \param bytes number of output bytes ready in the buffer
522
 */
523
EXPORT int mpg123_framebyframe_decode(mpg123_handle *mh, off_t *num, unsigned char **audio, size_t *bytes);
524
 
525
/** Find, read and parse the next mp3 frame
526
 * Warning: This is experimental API that might change in future releases!
527
 * Please watch mpg123 development closely when using it.
528
 */
529
EXPORT int mpg123_framebyframe_next(mpg123_handle *mh);
530
 
531
/** Get access to the raw input data for the last parsed frame.
532
 * This gives you a direct look (and write access) to the frame body data.
533
 * Together with the raw header, you can reconstruct the whole raw MPEG stream without junk and meta data, or play games by actually modifying the frame body data before decoding this frame (mpg123_framebyframe_decode()).
534
 * A more sane use would be to use this for CRC checking (see mpg123_info() and MPG123_CRC), the first two bytes of the body make up the CRC16 checksum, if present.
535
 * You can provide NULL for a parameter pointer when you are not interested in the value.
536
 *
537
 * \param header the 4-byte MPEG header
538
 * \param bodydata pointer to the frame body stored in the handle (without the header)
539
 * \param bodybytes size of frame body in bytes (without the header)
540
 * \return MPG123_OK if there was a yet un-decoded frame to get the data from, MPG123_ERR otherwise (without further explanation, the error state of the mpg123_handle is not modified by this function).
541
 */
542
EXPORT int mpg123_framedata(mpg123_handle *mh, unsigned long *header, unsigned char **bodydata, size_t *bodybytes);
543
 
544
/** Get the input position (byte offset in stream) of the last parsed frame.
545
 * This can be used for external seek index building, for example.
546
 * It just returns the internally stored offset, regardless of validity -- you ensure that a valid frame has been parsed before! */
547
EXPORT off_t mpg123_framepos(mpg123_handle *mh);
548
 
1905 serge 549
/*@}*/
550
 
551
 
552
/** \defgroup mpg123_seek mpg123 position and seeking
553
 *
554
 * Functions querying and manipulating position in the decoded audio bitstream.
555
 * The position is measured in decoded audio samples, or MPEG frame offset for the specific functions.
556
 * If gapless code is in effect, the positions are adjusted to compensate the skipped padding/delay - meaning, you should not care about that at all and just use the position defined for the samples you get out of the decoder;-)
557
 * The general usage is modelled after stdlib's ftell() and fseek().
558
 * Especially, the whence parameter for the seek functions has the same meaning as the one for fseek() and needs the same constants from stdlib.h:
559
 * - SEEK_SET: set position to (or near to) specified offset
560
 * - SEEK_CUR: change position by offset from now
561
 * - SEEK_END: set position to offset from end
562
 *
563
 * Note that sample-accurate seek only works when gapless support has been enabled at compile time; seek is frame-accurate otherwise.
564
 * Also, really sample-accurate seeking (meaning that you get the identical sample value after seeking compared to plain decoding up to the position) is only guaranteed when you do not mess with the position code by using MPG123_UPSPEED, MPG123_DOWNSPEED or MPG123_START_FRAME. The first two mainly should cause trouble with NtoM resampling, but in any case with these options in effect, you have to keep in mind that the sample offset is not the same as counting the samples you get from decoding since mpg123 counts the skipped samples, too (or the samples played twice only once)!
565
 * Short: When you care about the sample position, don't mess with those parameters;-)
566
 * Also, seeking is not guaranteed to work for all streams (underlying stream may not support it).
567
 *
568
 * @{
569
 */
570
 
571
/** Returns the current position in samples.
572
 *  On the next read, you'd get that sample. */
573
EXPORT off_t mpg123_tell(mpg123_handle *mh);
574
 
575
/** Returns the frame number that the next read will give you data from. */
576
EXPORT off_t mpg123_tellframe(mpg123_handle *mh);
577
 
578
/** Returns the current byte offset in the input stream. */
579
EXPORT off_t mpg123_tell_stream(mpg123_handle *mh);
580
 
581
/** Seek to a desired sample offset.
582
 *  Set whence to SEEK_SET, SEEK_CUR or SEEK_END.
583
 *  \return The resulting offset >= 0 or error/message code */
584
EXPORT off_t mpg123_seek(mpg123_handle *mh, off_t sampleoff, int whence);
585
 
586
/** Seek to a desired sample offset in data feeding mode.
587
 *  This just prepares things to be right only if you ensure that the next chunk of input data will be from input_offset byte position.
588
 *  \param input_offset The position it expects to be at the
589
 *                      next time data is fed to mpg123_decode().
590
 *  \return The resulting offset >= 0 or error/message code */
591
EXPORT off_t mpg123_feedseek(mpg123_handle *mh, off_t sampleoff, int whence, off_t *input_offset);
592
 
593
/** Seek to a desired MPEG frame index.
594
 *  Set whence to SEEK_SET, SEEK_CUR or SEEK_END.
595
 *  \return The resulting offset >= 0 or error/message code */
596
EXPORT off_t mpg123_seek_frame(mpg123_handle *mh, off_t frameoff, int whence);
597
 
598
/** Return a MPEG frame offset corresponding to an offset in seconds.
599
 *  This assumes that the samples per frame do not change in the file/stream, which is a good assumption for any sane file/stream only.
600
 *  \return frame offset >= 0 or error/message code */
601
EXPORT off_t mpg123_timeframe(mpg123_handle *mh, double sec);
602
 
603
/** Give access to the frame index table that is managed for seeking.
3960 Serge 604
 *  You are asked not to modify the values... Use mpg123_set_index to set the
605
 *  seek index
1905 serge 606
 *  \param offsets pointer to the index array
3960 Serge 607
 *  \param step one index byte offset advances this many MPEG frames
608
 *  \param fill number of recorded index offsets; size of the array */
1905 serge 609
EXPORT int mpg123_index(mpg123_handle *mh, off_t **offsets, off_t *step, size_t *fill);
610
 
3960 Serge 611
/** Set the frame index table
612
 *  Setting offsets to NULL and fill > 0 will allocate fill entries. Setting offsets
613
 *  to NULL and fill to 0 will clear the index and free the allocated memory used by the index.
614
 *  \param offsets pointer to the index array
615
 *  \param step    one index byte offset advances this many MPEG frames
616
 *  \param fill    number of recorded index offsets; size of the array */
617
EXPORT int mpg123_set_index(mpg123_handle *mh, off_t *offsets, off_t step, size_t fill);
618
 
1905 serge 619
/** Get information about current and remaining frames/seconds.
620
 *  WARNING: This function is there because of special usage by standalone mpg123 and may be removed in the final version of libmpg123!
621
 *  You provide an offset (in frames) from now and a number of output bytes
622
 *  served by libmpg123 but not yet played. You get the projected current frame
623
 *  and seconds, as well as the remaining frames/seconds. This does _not_ care
624
 *  about skipped samples due to gapless playback. */
3960 Serge 625
EXPORT int mpg123_position( mpg123_handle *mh, off_t frame_offset, off_t buffered_bytes, off_t *current_frame, off_t *frames_left, double *current_seconds, double *seconds_left);
1905 serge 626
 
627
/*@}*/
628
 
629
 
630
/** \defgroup mpg123_voleq mpg123 volume and equalizer
631
 *
632
 * @{
633
 */
634
 
635
enum mpg123_channels
636
{
637
	 MPG123_LEFT=0x1	/**< The Left Channel. */
638
	,MPG123_RIGHT=0x2	/**< The Right Channel. */
639
	,MPG123_LR=0x3	/**< Both left and right channel; same as MPG123_LEFT|MPG123_RIGHT */
640
};
641
 
642
/** Set the 32 Band Audio Equalizer settings.
643
 *  \param channel Can be MPG123_LEFT, MPG123_RIGHT or MPG123_LEFT|MPG123_RIGHT for both.
644
 *  \param band The equaliser band to change (from 0 to 31)
645
 *  \param val The (linear) adjustment factor. */
646
EXPORT int mpg123_eq(mpg123_handle *mh, enum mpg123_channels channel, int band, double val);
647
 
648
/** Get the 32 Band Audio Equalizer settings.
649
 *  \param channel Can be MPG123_LEFT, MPG123_RIGHT or MPG123_LEFT|MPG123_RIGHT for (arithmetic mean of) both.
650
 *  \param band The equaliser band to change (from 0 to 31)
651
 *  \return The (linear) adjustment factor. */
652
EXPORT double mpg123_geteq(mpg123_handle *mh, enum mpg123_channels channel, int band);
653
 
654
/** Reset the 32 Band Audio Equalizer settings to flat */
655
EXPORT int mpg123_reset_eq(mpg123_handle *mh);
656
 
657
/** Set the absolute output volume including the RVA setting,
658
 *  vol<0 just applies (a possibly changed) RVA setting. */
659
EXPORT int mpg123_volume(mpg123_handle *mh, double vol);
660
 
661
/** Adjust output volume including the RVA setting by chosen amount */
662
EXPORT int mpg123_volume_change(mpg123_handle *mh, double change);
663
 
664
/** Return current volume setting, the actual value due to RVA, and the RVA
665
 *  adjustment itself. It's all as double float value to abstract the sample
666
 *  format. The volume values are linear factors / amplitudes (not percent)
667
 *  and the RVA value is in decibels. */
668
EXPORT int mpg123_getvolume(mpg123_handle *mh, double *base, double *really, double *rva_db);
669
 
670
/* TODO: Set some preamp in addition / to replace internal RVA handling? */
671
 
672
/*@}*/
673
 
674
 
675
/** \defgroup mpg123_status mpg123 status and information
676
 *
677
 * @{
678
 */
679
 
680
/** Enumeration of the mode types of Variable Bitrate */
681
enum mpg123_vbr {
682
	MPG123_CBR=0,	/**< Constant Bitrate Mode (default) */
683
	MPG123_VBR,		/**< Variable Bitrate Mode */
684
	MPG123_ABR		/**< Average Bitrate Mode */
685
};
686
 
687
/** Enumeration of the MPEG Versions */
688
enum mpg123_version {
689
	MPG123_1_0=0,	/**< MPEG Version 1.0 */
690
	MPG123_2_0,		/**< MPEG Version 2.0 */
691
	MPG123_2_5		/**< MPEG Version 2.5 */
692
};
693
 
694
 
695
/** Enumeration of the MPEG Audio mode.
696
 *  Only the mono mode has 1 channel, the others have 2 channels. */
697
enum mpg123_mode {
698
	MPG123_M_STEREO=0,	/**< Standard Stereo. */
699
	MPG123_M_JOINT,		/**< Joint Stereo. */
700
	MPG123_M_DUAL,		/**< Dual Channel. */
701
	MPG123_M_MONO		/**< Single Channel. */
702
};
703
 
704
 
705
/** Enumeration of the MPEG Audio flag bits */
706
enum mpg123_flags {
707
	MPG123_CRC=0x1,			/**< The bitstream is error protected using 16-bit CRC. */
708
	MPG123_COPYRIGHT=0x2,	/**< The bitstream is copyrighted. */
709
	MPG123_PRIVATE=0x4,		/**< The private bit has been set. */
710
	MPG123_ORIGINAL=0x8	/**< The bitstream is an original, not a copy. */
711
};
712
 
713
/** Data structure for storing information about a frame of MPEG Audio */
714
struct mpg123_frameinfo
715
{
716
	enum mpg123_version version;	/**< The MPEG version (1.0/2.0/2.5). */
717
	int layer;						/**< The MPEG Audio Layer (MP1/MP2/MP3). */
718
	long rate; 						/**< The sampling rate in Hz. */
719
	enum mpg123_mode mode;			/**< The audio mode (Mono, Stereo, Joint-stero, Dual Channel). */
720
	int mode_ext;					/**< The mode extension bit flag. */
3960 Serge 721
	int framesize;					/**< The size of the frame (in bytes, including header). */
722
	enum mpg123_flags flags;		/**< MPEG Audio flag bits. Just now I realize that it should be declared as int, not enum. It's a bitwise combination of the enum values. */
1905 serge 723
	int emphasis;					/**< The emphasis type. */
724
	int bitrate;					/**< Bitrate of the frame (kbps). */
725
	int abr_rate;					/**< The target average bitrate. */
726
	enum mpg123_vbr vbr;			/**< The VBR mode. */
727
};
728
 
729
/** Get frame information about the MPEG audio bitstream and store it in a mpg123_frameinfo structure. */
730
EXPORT int mpg123_info(mpg123_handle *mh, struct mpg123_frameinfo *mi);
731
 
732
/** Get the safe output buffer size for all cases (when you want to replace the internal buffer) */
3960 Serge 733
EXPORT size_t mpg123_safe_buffer(void);
1905 serge 734
 
735
/** Make a full parsing scan of each frame in the file. ID3 tags are found. An accurate length
736
 *  value is stored. Seek index will be filled. A seek back to current position
737
 *  is performed. At all, this function refuses work when stream is
738
 *  not seekable.
739
 *  \return MPG123_OK or MPG123_ERR.
740
 */
741
EXPORT int mpg123_scan(mpg123_handle *mh);
742
 
743
/** Return, if possible, the full (expected) length of current track in samples.
744
  * \return length >= 0 or MPG123_ERR if there is no length guess possible. */
745
EXPORT off_t mpg123_length(mpg123_handle *mh);
746
 
747
/** Override the value for file size in bytes.
748
  * Useful for getting sensible track length values in feed mode or for HTTP streams.
749
  * \return MPG123_OK or MPG123_ERR */
750
EXPORT int mpg123_set_filesize(mpg123_handle *mh, off_t size);
751
 
752
/** Returns the time (seconds) per frame; <0 is error. */
753
EXPORT double mpg123_tpf(mpg123_handle *mh);
754
 
3960 Serge 755
/** Returns the samples per frame for the most recently parsed frame; <0 is error. */
756
EXPORT int mpg123_spf(mpg123_handle *mh);
757
 
1905 serge 758
/** Get and reset the clip count. */
759
EXPORT long mpg123_clip(mpg123_handle *mh);
760
 
761
 
762
/** The key values for state information from mpg123_getstate(). */
763
enum mpg123_state
764
{
765
	 MPG123_ACCURATE = 1 /**< Query if positons are currently accurate (integer value, 0 if false, 1 if true) */
3960 Serge 766
	,MPG123_BUFFERFILL   /**< Get fill of internal (feed) input buffer as integer byte count returned as long and as double. An error is returned on integer overflow while converting to (signed) long, but the returned floating point value shold still be fine. */
767
	,MPG123_FRANKENSTEIN /**< Stream consists of carelessly stitched together files (the leading one featuring gapless info).  */
1905 serge 768
};
769
 
770
/** Get various current decoder/stream state information.
771
 *  \param key the key to identify the information to give.
772
 *  \param val the address to return (long) integer values to
773
 *  \param fval the address to return floating point values to
774
 *  \return MPG123_OK or MPG123_ERR for success
775
 */
776
EXPORT int mpg123_getstate(mpg123_handle *mh, enum mpg123_state key, long *val, double *fval);
777
 
778
/*@}*/
779
 
780
 
781
/** \defgroup mpg123_metadata mpg123 metadata handling
782
 *
783
 * Functions to retrieve the metadata from MPEG Audio files and streams.
784
 * Also includes string handling functions.
785
 *
786
 * @{
787
 */
788
 
789
/** Data structure for storing strings in a safer way than a standard C-String.
790
 *  Can also hold a number of null-terminated strings. */
791
typedef struct
792
{
793
	char* p;     /**< pointer to the string data */
794
	size_t size; /**< raw number of bytes allocated */
795
	size_t fill; /**< number of used bytes (including closing zero byte) */
796
} mpg123_string;
797
 
798
/** Create and allocate memory for a new mpg123_string */
799
EXPORT void mpg123_init_string(mpg123_string* sb);
800
 
801
/** Free-up mempory for an existing mpg123_string */
802
EXPORT void mpg123_free_string(mpg123_string* sb);
803
 
804
/** Change the size of a mpg123_string
805
 *  \return 0 on error, 1 on success */
806
EXPORT int  mpg123_resize_string(mpg123_string* sb, size_t news);
807
 
808
/** Increase size of a mpg123_string if necessary (it may stay larger).
809
 *  Note that the functions for adding and setting in current libmpg123 use this instead of mpg123_resize_string().
810
 *  That way, you can preallocate memory and safely work afterwards with pieces.
811
 *  \return 0 on error, 1 on success */
812
EXPORT int  mpg123_grow_string(mpg123_string* sb, size_t news);
813
 
814
/** Copy the contents of one mpg123_string string to another.
815
 *  \return 0 on error, 1 on success */
816
EXPORT int  mpg123_copy_string(mpg123_string* from, mpg123_string* to);
817
 
818
/** Append a C-String to an mpg123_string
819
 *  \return 0 on error, 1 on success */
820
EXPORT int  mpg123_add_string(mpg123_string* sb, const char* stuff);
821
 
822
/** Append a C-substring to an mpg123 string
823
 *  \return 0 on error, 1 on success
824
 *  \param from offset to copy from
825
 *  \param count number of characters to copy (a null-byte is always appended) */
826
EXPORT int  mpg123_add_substring(mpg123_string *sb, const char *stuff, size_t from, size_t count);
827
 
828
/** Set the conents of a mpg123_string to a C-string
829
 *  \return 0 on error, 1 on success */
830
EXPORT int  mpg123_set_string(mpg123_string* sb, const char* stuff);
831
 
832
/** Set the contents of a mpg123_string to a C-substring
833
 *  \return 0 on error, 1 on success
834
 *  \param from offset to copy from
835
 *  \param count number of characters to copy (a null-byte is always appended) */
836
EXPORT int  mpg123_set_substring(mpg123_string *sb, const char *stuff, size_t from, size_t count);
837
 
3960 Serge 838
/** Count characters in a mpg123 string (non-null bytes or UTF-8 characters).
839
 *  \return character count
840
 *  \param sb the string
841
 *  \param utf8 a flag to tell if the string is in utf8 encoding
842
 *  Even with the fill property, the character count is not obvious as there could be multiple trailing null bytes.
843
*/
844
EXPORT size_t mpg123_strlen(mpg123_string *sb, int utf8);
845
 
846
/** Remove trailing \r and \n, if present.
847
 *  \return 0 on error, 1 on success
848
 *  \param sb the string
849
 */
850
EXPORT int mpg123_chomp_string(mpg123_string *sb);
851
 
1905 serge 852
/** The mpg123 text encodings. This contains encodings we encounter in ID3 tags or ICY meta info. */
853
enum mpg123_text_encoding
854
{
855
	 mpg123_text_unknown  = 0 /**< Unkown encoding... mpg123_id3_encoding can return that on invalid codes. */
856
	,mpg123_text_utf8     = 1 /**< UTF-8 */
857
	,mpg123_text_latin1   = 2 /**< ISO-8859-1. Note that sometimes latin1 in ID3 is abused for totally different encodings. */
858
	,mpg123_text_icy      = 3 /**< ICY metadata encoding, usually CP-1252 but we take it as UTF-8 if it qualifies as such. */
859
	,mpg123_text_cp1252   = 4 /**< Really CP-1252 without any guessing. */
860
	,mpg123_text_utf16    = 5 /**< Some UTF-16 encoding. The last of a set of leading BOMs (byte order mark) rules.
861
	                           *   When there is no BOM, big endian ordering is used. Note that UCS-2 qualifies as UTF-8 when
862
	                           *   you don't mess with the reserved code points. If you want to decode little endian data
863
	                           *   without BOM you need to prepend 0xff 0xfe yourself. */
864
	,mpg123_text_utf16bom = 6 /**< Just an alias for UTF-16, ID3v2 has this as distinct code. */
865
	,mpg123_text_utf16be  = 7 /**< Another alias for UTF16 from ID3v2. Note, that, because of the mess that is reality,
866
	                           *   BOMs are used if encountered. There really is not much distinction between the UTF16 types for mpg123
867
	                           *   One exception: Since this is seen in ID3v2 tags, leading null bytes are skipped for all other UTF16
868
	                           *   types (we expect a BOM before real data there), not so for utf16be!*/
869
	,mpg123_text_max      = 7 /**< Placeholder for the maximum encoding value. */
870
};
871
 
872
/** The encoding byte values from ID3v2. */
873
enum mpg123_id3_enc
874
{
875
	 mpg123_id3_latin1   = 0 /**< Note: This sometimes can mean anything in practice... */
876
	,mpg123_id3_utf16bom = 1 /**< UTF16, UCS-2 ... it's all the same for practical purposes. */
877
	,mpg123_id3_utf16be  = 2 /**< Big-endian UTF-16, BOM see note for mpg123_text_utf16be. */
878
	,mpg123_id3_utf8     = 3 /**< Our lovely overly ASCII-compatible 8 byte encoding for the world. */
879
	,mpg123_id3_enc_max  = 3 /**< Placeholder to check valid range of encoding byte. */
880
};
881
 
882
/** Convert ID3 encoding byte to mpg123 encoding index. */
883
EXPORT enum mpg123_text_encoding mpg123_enc_from_id3(unsigned char id3_enc_byte);
884
 
885
/** Store text data in string, after converting to UTF-8 from indicated encoding
886
 *  \return 0 on error, 1 on success (on error, mpg123_free_string is called on sb)
887
 *  \param sb  target string
888
 *  \param enc mpg123 text encoding value
889
 *  \param source source buffer with plain unsigned bytes (you might need to cast from char *)
890
 *  \param source_size number of bytes in the source buffer
891
 *
892
 *  A prominent error can be that you provided an unknown encoding value, or this build of libmpg123 lacks support for certain encodings (ID3 or ICY stuff missing).
893
 *  Also, you might want to take a bit of care with preparing the data; for example, strip leading zeroes (I have seen that).
894
 */
895
EXPORT int mpg123_store_utf8(mpg123_string *sb, enum mpg123_text_encoding enc, const unsigned char *source, size_t source_size);
896
 
897
/** Sub data structure for ID3v2, for storing various text fields (including comments).
898
 *  This is for ID3v2 COMM, TXXX and all the other text fields.
899
 *  Only COMM and TXXX have a description, only COMM and USLT have a language.
900
 *  You should consult the ID3v2 specification for the use of the various text fields ("frames" in ID3v2 documentation, I use "fields" here to separate from MPEG frames). */
901
typedef struct
902
{
903
	char lang[3]; /**< Three-letter language code (not terminated). */
904
	char id[4];   /**< The ID3v2 text field id, like TALB, TPE2, ... (4 characters, no string termination). */
905
	mpg123_string description; /**< Empty for the generic comment... */
906
	mpg123_string text;        /**< ... */
907
} mpg123_text;
908
 
909
/** Data structure for storing IDV3v2 tags.
910
 *  This structure is not a direct binary mapping with the file contents.
911
 *  The ID3v2 text frames are allowed to contain multiple strings.
912
 *  So check for null bytes until you reach the mpg123_string fill.
913
 *  All text is encoded in UTF-8. */
914
typedef struct
915
{
916
	unsigned char version; /**< 3 or 4 for ID3v2.3 or ID3v2.4. */
917
	mpg123_string *title;   /**< Title string (pointer into text_list). */
918
	mpg123_string *artist;  /**< Artist string (pointer into text_list). */
919
	mpg123_string *album;   /**< Album string (pointer into text_list). */
920
	mpg123_string *year;    /**< The year as a string (pointer into text_list). */
921
	mpg123_string *genre;   /**< Genre String (pointer into text_list). The genre string(s) may very well need postprocessing, esp. for ID3v2.3. */
922
	mpg123_string *comment; /**< Pointer to last encountered comment text with empty description. */
923
	/* Encountered ID3v2 fields are appended to these lists.
924
	   There can be multiple occurences, the pointers above always point to the last encountered data. */
925
	mpg123_text    *comment_list; /**< Array of comments. */
926
	size_t          comments;     /**< Number of comments. */
927
	mpg123_text    *text;         /**< Array of ID3v2 text fields (including USLT) */
928
	size_t          texts;        /**< Numer of text fields. */
929
	mpg123_text    *extra;        /**< The array of extra (TXXX) fields. */
930
	size_t          extras;       /**< Number of extra text (TXXX) fields. */
931
} mpg123_id3v2;
932
 
933
/** Data structure for ID3v1 tags (the last 128 bytes of a file).
934
 *  Don't take anything for granted (like string termination)!
935
 *  Also note the change ID3v1.1 did: comment[28] = 0; comment[19] = track_number
936
 *  It is your task to support ID3v1 only or ID3v1.1 ...*/
937
typedef struct
938
{
939
	char tag[3];         /**< Always the string "TAG", the classic intro. */
940
	char title[30];      /**< Title string.  */
941
	char artist[30];     /**< Artist string. */
942
	char album[30];      /**< Album string. */
943
	char year[4];        /**< Year string. */
944
	char comment[30];    /**< Comment string. */
945
	unsigned char genre; /**< Genre index. */
946
} mpg123_id3v1;
947
 
948
#define MPG123_ID3     0x3 /**< 0011 There is some ID3 info. Also matches 0010 or NEW_ID3. */
949
#define MPG123_NEW_ID3 0x1 /**< 0001 There is ID3 info that changed since last call to mpg123_id3. */
950
#define MPG123_ICY     0xc /**< 1100 There is some ICY info. Also matches 0100 or NEW_ICY.*/
951
#define MPG123_NEW_ICY 0x4 /**< 0100 There is ICY info that changed since last call to mpg123_icy. */
952
 
953
/** Query if there is (new) meta info, be it ID3 or ICY (or something new in future).
954
   The check function returns a combination of flags. */
955
EXPORT int mpg123_meta_check(mpg123_handle *mh); /* On error (no valid handle) just 0 is returned. */
956
 
3960 Serge 957
/** Clean up meta data storage (ID3v2 and ICY), freeing memory. */
958
EXPORT void mpg123_meta_free(mpg123_handle *mh);
959
 
1905 serge 960
/** Point v1 and v2 to existing data structures wich may change on any next read/decode function call.
961
 *  v1 and/or v2 can be set to NULL when there is no corresponding data.
962
 *  \return Return value is MPG123_OK or MPG123_ERR,  */
963
EXPORT int mpg123_id3(mpg123_handle *mh, mpg123_id3v1 **v1, mpg123_id3v2 **v2);
964
 
965
/** Point icy_meta to existing data structure wich may change on any next read/decode function call.
966
 *  \return Return value is MPG123_OK or MPG123_ERR,  */
967
EXPORT int mpg123_icy(mpg123_handle *mh, char **icy_meta); /* same for ICY meta string */
968
 
969
/** Decode from windows-1252 (the encoding ICY metainfo used) to UTF-8.
970
 *  Note that this is very similar to mpg123_store_utf8(&sb, mpg123_text_icy, icy_text, strlen(icy_text+1)) .
971
 *  \param icy_text The input data in ICY encoding
972
 *  \return pointer to newly allocated buffer with UTF-8 data (You free() it!) */
973
EXPORT char* mpg123_icy2utf8(const char* icy_text);
974
 
975
 
976
/* @} */
977
 
978
 
979
/** \defgroup mpg123_advpar mpg123 advanced parameter API
980
 *
981
 *  Direct access to a parameter set without full handle around it.
982
 *	Possible uses:
983
 *    - Influence behaviour of library _during_ initialization of handle (MPG123_VERBOSE).
984
 *    - Use one set of parameters for multiple handles.
985
 *
986
 *	The functions for handling mpg123_pars (mpg123_par() and mpg123_fmt()
987
 *  family) directly return a fully qualified mpg123 error code, the ones
988
 *  operating on full handles normally MPG123_OK or MPG123_ERR, storing the
989
 *  specific error code itseld inside the handle.
990
 *
991
 * @{
992
 */
993
 
994
/** Opaque structure for the libmpg123 decoder parameters. */
995
struct mpg123_pars_struct;
996
 
997
/** Opaque structure for the libmpg123 decoder parameters. */
998
typedef struct mpg123_pars_struct   mpg123_pars;
999
 
1000
/** Create a handle with preset parameters. */
1001
EXPORT mpg123_handle *mpg123_parnew(mpg123_pars *mp, const char* decoder, int *error);
1002
 
1003
/** Allocate memory for and return a pointer to a new mpg123_pars */
1004
EXPORT mpg123_pars *mpg123_new_pars(int *error);
1005
 
1006
/** Delete and free up memory used by a mpg123_pars data structure */
1007
EXPORT void         mpg123_delete_pars(mpg123_pars* mp);
1008
 
1009
/** Configure mpg123 parameters to accept no output format at all,
1010
 * use before specifying supported formats with mpg123_format */
1011
EXPORT int mpg123_fmt_none(mpg123_pars *mp);
1012
 
1013
/** Configure mpg123 parameters to accept all formats
1014
 *  (also any custom rate you may set) -- this is default. */
1015
EXPORT int mpg123_fmt_all(mpg123_pars *mp);
1016
 
1017
/** Set the audio format support of a mpg123_pars in detail:
1018
	\param rate The sample rate value (in Hertz).
1019
	\param channels A combination of MPG123_STEREO and MPG123_MONO.
1020
	\param encodings A combination of accepted encodings for rate and channels, p.ex MPG123_ENC_SIGNED16|MPG123_ENC_ULAW_8 (or 0 for no support).
1021
	\return 0 on success, -1 if there was an error. /
1022
*/
1023
EXPORT int mpg123_fmt(mpg123_pars *mh, long rate, int channels, int encodings); /* 0 is good, -1 is error */
1024
 
1025
/** Check to see if a specific format at a specific rate is supported
1026
 *  by mpg123_pars.
1027
 *  \return 0 for no support (that includes invalid parameters), MPG123_STEREO,
1028
 *          MPG123_MONO or MPG123_STEREO|MPG123_MONO. */
1029
EXPORT int mpg123_fmt_support(mpg123_pars *mh,   long rate, int encoding);
1030
 
1031
/** Set a specific parameter, for a specific mpg123_pars, using a parameter
1032
 *  type key chosen from the mpg123_parms enumeration, to the specified value. */
1033
EXPORT int mpg123_par(mpg123_pars *mp, enum mpg123_parms type, long value, double fvalue);
1034
 
1035
/** Get a specific parameter, for a specific mpg123_pars.
1036
 *  See the mpg123_parms enumeration for a list of available parameters. */
1037
EXPORT int mpg123_getpar(mpg123_pars *mp, enum mpg123_parms type, long *val, double *fval);
1038
 
1039
/* @} */
1040
 
1041
 
1042
/** \defgroup mpg123_lowio mpg123 low level I/O
1043
  * You may want to do tricky stuff with I/O that does not work with mpg123's default file access or you want to make it decode into your own pocket...
1044
  *
1045
  * @{ */
1046
 
1047
/** Replace default internal buffer with user-supplied buffer.
1048
  * Instead of working on it's own private buffer, mpg123 will directly use the one you provide for storing decoded audio. */
1049
EXPORT int mpg123_replace_buffer(mpg123_handle *mh, unsigned char *data, size_t size);
1050
 
1051
/** The max size of one frame's decoded output with current settings.
1052
 *  Use that to determine an appropriate minimum buffer size for decoding one frame. */
1053
EXPORT size_t mpg123_outblock(mpg123_handle *mh);
1054
 
1055
/** Replace low-level stream access functions; read and lseek as known in POSIX.
1056
 *  You can use this to make any fancy file opening/closing yourself,
3960 Serge 1057
 *  using mpg123_open_fd() to set the file descriptor for your read/lseek (doesn't need to be a "real" file descriptor...).
1905 serge 1058
 *  Setting a function to NULL means that the default internal read is
3960 Serge 1059
 *  used (active from next mpg123_open call on).
1060
 *  Note: As it would be troublesome to mess with this while having a file open,
1061
 *  this implies mpg123_close(). */
1062
EXPORT int mpg123_replace_reader(mpg123_handle *mh, ssize_t (*r_read) (int, void *, size_t), off_t (*r_lseek)(int, off_t, int));
1905 serge 1063
 
3960 Serge 1064
/** Replace I/O functions with your own ones operating on some kind of handle instead of integer descriptors.
1065
 *  The handle is a void pointer, so you can pass any data you want...
1066
 *  mpg123_open_handle() is the call you make to use the I/O defined here.
1067
 *  There is no fallback to internal read/seek here.
1068
 *  Note: As it would be troublesome to mess with this while having a file open,
1069
 *  this mpg123_close() is implied here.
1070
 *  \param r_read The callback for reading (behaviour like posix read).
1071
 *  \param r_lseek The callback for seeking (like posix lseek).
1072
 *  \param cleanup A callback to clean up an I/O handle on mpg123_close, can be NULL for none (you take care of cleaning your handles). */
1073
EXPORT int mpg123_replace_reader_handle(mpg123_handle *mh, ssize_t (*r_read) (void *, void *, size_t), off_t (*r_lseek)(void *, off_t, int), void (*cleanup)(void*));
1074
 
1905 serge 1075
/* @} */
1076
 
1077
#ifdef __cplusplus
1078
}
1079
#endif
1080
 
1081
#endif