00001 /* 00002 * Asterisk -- An open source telephony toolkit. 00003 * 00004 * Copyright (C) 1999 - 2005, Digium, Inc. 00005 * 00006 * Mark Spencer <markster@digium.com> 00007 * 00008 * See http://www.asterisk.org for more information about 00009 * the Asterisk project. Please do not directly contact 00010 * any of the maintainers of this project for assistance; 00011 * the project provides a web site, mailing lists and IRC 00012 * channels for your use. 00013 * 00014 * This program is free software, distributed under the terms of 00015 * the GNU General Public License Version 2. See the LICENSE file 00016 * at the top of the source tree. 00017 */ 00018 00019 /*! \file 00020 * \brief Asterisk internal frame definitions. 00021 * \arg For an explanation of frames, see \ref Def_Frame 00022 * \arg Frames are send of Asterisk channels, see \ref Def_Channel 00023 */ 00024 00025 #ifndef _ASTERISK_FRAME_H 00026 #define _ASTERISK_FRAME_H 00027 00028 #if defined(__cplusplus) || defined(c_plusplus) 00029 extern "C" { 00030 #endif 00031 00032 #include <sys/time.h> 00033 00034 #include "asterisk/endian.h" 00035 #include "asterisk/linkedlists.h" 00036 00037 struct ast_codec_pref { 00038 char order[32]; 00039 char framing[32]; 00040 }; 00041 00042 /*! \page Def_Frame AST Multimedia and signalling frames 00043 \section Def_AstFrame What is an ast_frame ? 00044 A frame of data read used to communicate between 00045 between channels and applications. 00046 Frames are divided into frame types and subclasses. 00047 00048 \par Frame types 00049 \arg \b VOICE: Voice data, subclass is codec (AST_FORMAT_*) 00050 \arg \b VIDEO: Video data, subclass is codec (AST_FORMAT_*) 00051 \arg \b DTMF: A DTMF digit, subclass is the digit 00052 \arg \b IMAGE: Image transport, mostly used in IAX 00053 \arg \b TEXT: Text messages and character by character (real time text) 00054 \arg \b HTML: URL's and web pages 00055 \arg \b MODEM: Modulated data encodings, such as T.38 and V.150 00056 \arg \b IAX: Private frame type for the IAX protocol 00057 \arg \b CNG: Comfort noice frames 00058 \arg \b CONTROL: A control frame, subclass defined as AST_CONTROL_ 00059 \arg \b NULL: Empty, useless frame 00060 00061 \par Files 00062 \arg frame.h Definitions 00063 \arg frame.c Function library 00064 \arg \ref Def_Channel Asterisk channels 00065 \section Def_ControlFrame Control Frames 00066 Control frames send signalling information between channels 00067 and devices. They are prefixed with AST_CONTROL_, like AST_CONTROL_FRAME_HANGUP 00068 \arg \b HANGUP The other end has hungup 00069 \arg \b RING Local ring 00070 \arg \b RINGING The other end is ringing 00071 \arg \b ANSWER The other end has answered 00072 \arg \b BUSY Remote end is busy 00073 \arg \b TAKEOFFHOOK Make it go off hook (what's "it" ? ) 00074 \arg \b OFFHOOK Line is off hook 00075 \arg \b CONGESTION Congestion (circuit is busy, not available) 00076 \arg \b FLASH Other end sends flash hook 00077 \arg \b WINK Other end sends wink 00078 \arg \b OPTION Send low-level option 00079 \arg \b RADIO_KEY Key radio (see app_rpt.c) 00080 \arg \b RADIO_UNKEY Un-key radio (see app_rpt.c) 00081 \arg \b PROGRESS Other end indicates call progress 00082 \arg \b PROCEEDING Indicates proceeding 00083 \arg \b HOLD Call is placed on hold 00084 \arg \b UNHOLD Call is back from hold 00085 \arg \b VIDUPDATE Video update requested 00086 \arg \b SRCUPDATE The source of media has changed (RTP marker bit must change) 00087 \arg \b SRCCHANGE Media source has changed (RTP marker bit and SSRC must change) 00088 00089 */ 00090 00091 /*! 00092 * \brief Frame types 00093 * 00094 * \note It is important that the values of each frame type are never changed, 00095 * because it will break backwards compatability with older versions. 00096 * This is because these constants are transmitted directly over IAX2. 00097 */ 00098 enum ast_frame_type { 00099 /*! DTMF end event, subclass is the digit */ 00100 AST_FRAME_DTMF_END = 1, 00101 /*! Voice data, subclass is AST_FORMAT_* */ 00102 AST_FRAME_VOICE, 00103 /*! Video frame, maybe?? :) */ 00104 AST_FRAME_VIDEO, 00105 /*! A control frame, subclass is AST_CONTROL_* */ 00106 AST_FRAME_CONTROL, 00107 /*! An empty, useless frame */ 00108 AST_FRAME_NULL, 00109 /*! Inter Asterisk Exchange private frame type */ 00110 AST_FRAME_IAX, 00111 /*! Text messages */ 00112 AST_FRAME_TEXT, 00113 /*! Image Frames */ 00114 AST_FRAME_IMAGE, 00115 /*! HTML Frame */ 00116 AST_FRAME_HTML, 00117 /*! Comfort Noise frame (subclass is level of CNG in -dBov), 00118 body may include zero or more 8-bit quantization coefficients */ 00119 AST_FRAME_CNG, 00120 /*! Modem-over-IP data streams */ 00121 AST_FRAME_MODEM, 00122 /*! DTMF begin event, subclass is the digit */ 00123 AST_FRAME_DTMF_BEGIN, 00124 }; 00125 #define AST_FRAME_DTMF AST_FRAME_DTMF_END 00126 00127 enum { 00128 /*! This frame contains valid timing information */ 00129 AST_FRFLAG_HAS_TIMING_INFO = (1 << 0), 00130 }; 00131 00132 /*! \brief Data structure associated with a single frame of data 00133 */ 00134 struct ast_frame { 00135 /*! Kind of frame */ 00136 enum ast_frame_type frametype; 00137 /*! Subclass, frame dependent */ 00138 int subclass; 00139 /*! Length of data */ 00140 int datalen; 00141 /*! Number of samples in this frame */ 00142 int samples; 00143 /*! Was the data malloc'd? i.e. should we free it when we discard the frame? */ 00144 int mallocd; 00145 /*! The number of bytes allocated for a malloc'd frame header */ 00146 size_t mallocd_hdr_len; 00147 /*! How many bytes exist _before_ "data" that can be used if needed */ 00148 int offset; 00149 /*! Optional source of frame for debugging */ 00150 const char *src; 00151 /*! Pointer to actual data */ 00152 union { void *ptr; uint32_t uint32; char pad[8]; } data; 00153 /*! Global delivery time */ 00154 struct timeval delivery; 00155 /*! For placing in a linked list */ 00156 AST_LIST_ENTRY(ast_frame) frame_list; 00157 /*! Misc. frame flags */ 00158 unsigned int flags; 00159 /*! Timestamp in milliseconds */ 00160 long ts; 00161 /*! Length in milliseconds */ 00162 long len; 00163 /*! Sequence number */ 00164 int seqno; 00165 }; 00166 00167 /*! 00168 * Set the various field of a frame to point to a buffer. 00169 * Typically you set the base address of the buffer, the offset as 00170 * AST_FRIENDLY_OFFSET, and the datalen as the amount of bytes queued. 00171 * The remaining things (to be done manually) is set the number of 00172 * samples, which cannot be derived from the datalen unless you know 00173 * the number of bits per sample. 00174 */ 00175 #define AST_FRAME_SET_BUFFER(fr, _base, _ofs, _datalen) \ 00176 { \ 00177 (fr)->data.ptr = (char *)_base + (_ofs); \ 00178 (fr)->offset = (_ofs); \ 00179 (fr)->datalen = (_datalen); \ 00180 } 00181 00182 /*! Queueing a null frame is fairly common, so we declare a global null frame object 00183 for this purpose instead of having to declare one on the stack */ 00184 extern struct ast_frame ast_null_frame; 00185 00186 /*! \brief Offset into a frame's data buffer. 00187 * 00188 * By providing some "empty" space prior to the actual data of an ast_frame, 00189 * this gives any consumer of the frame ample space to prepend other necessary 00190 * information without having to create a new buffer. 00191 * 00192 * As an example, RTP can use the data from an ast_frame and simply prepend the 00193 * RTP header information into the space provided by AST_FRIENDLY_OFFSET instead 00194 * of having to create a new buffer with the necessary space allocated. 00195 */ 00196 #define AST_FRIENDLY_OFFSET 64 00197 #define AST_MIN_OFFSET 32 /*! Make sure we keep at least this much handy */ 00198 00199 /*! Need the header be free'd? */ 00200 #define AST_MALLOCD_HDR (1 << 0) 00201 /*! Need the data be free'd? */ 00202 #define AST_MALLOCD_DATA (1 << 1) 00203 /*! Need the source be free'd? (haha!) */ 00204 #define AST_MALLOCD_SRC (1 << 2) 00205 00206 /* MODEM subclasses */ 00207 /*! T.38 Fax-over-IP */ 00208 #define AST_MODEM_T38 1 00209 /*! V.150 Modem-over-IP */ 00210 #define AST_MODEM_V150 2 00211 00212 /* HTML subclasses */ 00213 /*! Sending a URL */ 00214 #define AST_HTML_URL 1 00215 /*! Data frame */ 00216 #define AST_HTML_DATA 2 00217 /*! Beginning frame */ 00218 #define AST_HTML_BEGIN 4 00219 /*! End frame */ 00220 #define AST_HTML_END 8 00221 /*! Load is complete */ 00222 #define AST_HTML_LDCOMPLETE 16 00223 /*! Peer is unable to support HTML */ 00224 #define AST_HTML_NOSUPPORT 17 00225 /*! Send URL, and track */ 00226 #define AST_HTML_LINKURL 18 00227 /*! No more HTML linkage */ 00228 #define AST_HTML_UNLINK 19 00229 /*! Reject link request */ 00230 #define AST_HTML_LINKREJECT 20 00231 00232 /* Data formats for capabilities and frames alike */ 00233 /*! G.723.1 compression */ 00234 #define AST_FORMAT_G723_1 (1 << 0) 00235 /*! GSM compression */ 00236 #define AST_FORMAT_GSM (1 << 1) 00237 /*! Raw mu-law data (G.711) */ 00238 #define AST_FORMAT_ULAW (1 << 2) 00239 /*! Raw A-law data (G.711) */ 00240 #define AST_FORMAT_ALAW (1 << 3) 00241 /*! ADPCM (G.726, 32kbps, AAL2 codeword packing) */ 00242 #define AST_FORMAT_G726_AAL2 (1 << 4) 00243 /*! ADPCM (IMA) */ 00244 #define AST_FORMAT_ADPCM (1 << 5) 00245 /*! Raw 16-bit Signed Linear (8000 Hz) PCM */ 00246 #define AST_FORMAT_SLINEAR (1 << 6) 00247 /*! LPC10, 180 samples/frame */ 00248 #define AST_FORMAT_LPC10 (1 << 7) 00249 /*! G.729A audio */ 00250 #define AST_FORMAT_G729A (1 << 8) 00251 /*! SpeeX Free Compression */ 00252 #define AST_FORMAT_SPEEX (1 << 9) 00253 /*! iLBC Free Compression */ 00254 #define AST_FORMAT_ILBC (1 << 10) 00255 /*! ADPCM (G.726, 32kbps, RFC3551 codeword packing) */ 00256 #define AST_FORMAT_G726 (1 << 11) 00257 /*! G.722 */ 00258 #define AST_FORMAT_G722 (1 << 12) 00259 /*! Unsupported audio bits */ 00260 #define AST_FORMAT_AUDIO_UNDEFINED ((1 << 13) | (1 << 14)) 00261 /*! Raw 16-bit Signed Linear (16000 Hz) PCM */ 00262 #define AST_FORMAT_SLINEAR16 (1 << 15) 00263 /*! Maximum audio mask */ 00264 #define AST_FORMAT_AUDIO_MASK ((1 << 16)-1) 00265 /*! JPEG Images */ 00266 #define AST_FORMAT_JPEG (1 << 16) 00267 /*! PNG Images */ 00268 #define AST_FORMAT_PNG (1 << 17) 00269 /*! H.261 Video */ 00270 #define AST_FORMAT_H261 (1 << 18) 00271 /*! H.263 Video */ 00272 #define AST_FORMAT_H263 (1 << 19) 00273 /*! H.263+ Video */ 00274 #define AST_FORMAT_H263_PLUS (1 << 20) 00275 /*! H.264 Video */ 00276 #define AST_FORMAT_H264 (1 << 21) 00277 /*! MPEG4 Video */ 00278 #define AST_FORMAT_MP4_VIDEO (1 << 22) 00279 #define AST_FORMAT_VIDEO_MASK (((1 << 25)-1) & ~(AST_FORMAT_AUDIO_MASK)) 00280 /*! T.140 RED Text format RFC 4103 */ 00281 #define AST_FORMAT_T140RED (1 << 26) 00282 /*! T.140 Text format - ITU T.140, RFC 4103 */ 00283 #define AST_FORMAT_T140 (1 << 27) 00284 /*! Maximum text mask */ 00285 #define AST_FORMAT_MAX_TEXT (1 << 28)) 00286 #define AST_FORMAT_TEXT_MASK (((1 << 30)-1) & ~(AST_FORMAT_AUDIO_MASK) & ~(AST_FORMAT_VIDEO_MASK)) 00287 00288 enum ast_control_frame_type { 00289 AST_CONTROL_HANGUP = 1, /*!< Other end has hungup */ 00290 AST_CONTROL_RING = 2, /*!< Local ring */ 00291 AST_CONTROL_RINGING = 3, /*!< Remote end is ringing */ 00292 AST_CONTROL_ANSWER = 4, /*!< Remote end has answered */ 00293 AST_CONTROL_BUSY = 5, /*!< Remote end is busy */ 00294 AST_CONTROL_TAKEOFFHOOK = 6, /*!< Make it go off hook */ 00295 AST_CONTROL_OFFHOOK = 7, /*!< Line is off hook */ 00296 AST_CONTROL_CONGESTION = 8, /*!< Congestion (circuits busy) */ 00297 AST_CONTROL_FLASH = 9, /*!< Flash hook */ 00298 AST_CONTROL_WINK = 10, /*!< Wink */ 00299 AST_CONTROL_OPTION = 11, /*!< Set a low-level option */ 00300 AST_CONTROL_RADIO_KEY = 12, /*!< Key Radio */ 00301 AST_CONTROL_RADIO_UNKEY = 13, /*!< Un-Key Radio */ 00302 AST_CONTROL_PROGRESS = 14, /*!< Indicate PROGRESS */ 00303 AST_CONTROL_PROCEEDING = 15, /*!< Indicate CALL PROCEEDING */ 00304 AST_CONTROL_HOLD = 16, /*!< Indicate call is placed on hold */ 00305 AST_CONTROL_UNHOLD = 17, /*!< Indicate call is left from hold */ 00306 AST_CONTROL_VIDUPDATE = 18, /*!< Indicate video frame update */ 00307 _XXX_AST_CONTROL_T38 = 19, /*!< T38 state change request/notification \deprecated This is no longer supported. Use AST_CONTROL_T38_PARAMETERS instead. */ 00308 AST_CONTROL_SRCUPDATE = 20, /*!< Indicate source of media has changed */ 00309 AST_CONTROL_T38_PARAMETERS = 24, /*!< T38 state change request/notification with parameters */ 00310 AST_CONTROL_SRCCHANGE = 25, /*!< Media source has changed and requires a new RTP SSRC */ 00311 }; 00312 00313 enum ast_control_t38 { 00314 AST_T38_REQUEST_NEGOTIATE = 1, /*!< Request T38 on a channel (voice to fax) */ 00315 AST_T38_REQUEST_TERMINATE, /*!< Terminate T38 on a channel (fax to voice) */ 00316 AST_T38_NEGOTIATED, /*!< T38 negotiated (fax mode) */ 00317 AST_T38_TERMINATED, /*!< T38 terminated (back to voice) */ 00318 AST_T38_REFUSED /*!< T38 refused for some reason (usually rejected by remote end) */ 00319 }; 00320 00321 enum ast_control_t38_rate { 00322 AST_T38_RATE_2400 = 0, 00323 AST_T38_RATE_4800, 00324 AST_T38_RATE_7200, 00325 AST_T38_RATE_9600, 00326 AST_T38_RATE_12000, 00327 AST_T38_RATE_14400, 00328 }; 00329 00330 enum ast_control_t38_rate_management { 00331 AST_T38_RATE_MANAGEMENT_TRANSFERRED_TCF = 0, 00332 AST_T38_RATE_MANAGEMENT_LOCAL_TCF, 00333 }; 00334 00335 struct ast_control_t38_parameters { 00336 enum ast_control_t38 request_response; /*!< Request or response of the T38 control frame */ 00337 unsigned int version; /*!< Supported T.38 version */ 00338 unsigned int max_ifp; /*!< Maximum IFP size supported */ 00339 enum ast_control_t38_rate rate; /*!< Maximum fax rate supported */ 00340 enum ast_control_t38_rate_management rate_management; /*!< Rate management setting */ 00341 unsigned int fill_bit_removal:1; /*!< Set if fill bit removal can be used */ 00342 unsigned int transcoding_mmr:1; /*!< Set if MMR transcoding can be used */ 00343 unsigned int transcoding_jbig:1; /*!< Set if JBIG transcoding can be used */ 00344 }; 00345 00346 #define AST_SMOOTHER_FLAG_G729 (1 << 0) 00347 #define AST_SMOOTHER_FLAG_BE (1 << 1) 00348 00349 /* Option identifiers and flags */ 00350 #define AST_OPTION_FLAG_REQUEST 0 00351 #define AST_OPTION_FLAG_ACCEPT 1 00352 #define AST_OPTION_FLAG_REJECT 2 00353 #define AST_OPTION_FLAG_QUERY 4 00354 #define AST_OPTION_FLAG_ANSWER 5 00355 #define AST_OPTION_FLAG_WTF 6 00356 00357 /*! Verify touchtones by muting audio transmission 00358 (and reception) and verify the tone is still present */ 00359 #define AST_OPTION_TONE_VERIFY 1 00360 00361 /*! Put a compatible channel into TDD (TTY for the hearing-impared) mode */ 00362 #define AST_OPTION_TDD 2 00363 00364 /*! Relax the parameters for DTMF reception (mainly for radio use) */ 00365 #define AST_OPTION_RELAXDTMF 3 00366 00367 /*! Set (or clear) Audio (Not-Clear) Mode */ 00368 #define AST_OPTION_AUDIO_MODE 4 00369 00370 /*! Set channel transmit gain 00371 * Option data is a single signed char 00372 representing number of decibels (dB) 00373 to set gain to (on top of any gain 00374 specified in channel driver) 00375 */ 00376 #define AST_OPTION_TXGAIN 5 00377 00378 /*! Set channel receive gain 00379 * Option data is a single signed char 00380 representing number of decibels (dB) 00381 to set gain to (on top of any gain 00382 specified in channel driver) 00383 */ 00384 #define AST_OPTION_RXGAIN 6 00385 00386 /* set channel into "Operator Services" mode */ 00387 #define AST_OPTION_OPRMODE 7 00388 00389 /*! Explicitly enable or disable echo cancelation for the given channel */ 00390 #define AST_OPTION_ECHOCAN 8 00391 00392 /* ! 00393 * Read-only. Allows query current status of T38 on the channel. 00394 * data: ast_t38state 00395 */ 00396 #define AST_OPTION_T38_STATE 10 00397 00398 struct oprmode { 00399 struct ast_channel *peer; 00400 int mode; 00401 } ; 00402 00403 struct ast_option_header { 00404 /* Always keep in network byte order */ 00405 #if __BYTE_ORDER == __BIG_ENDIAN 00406 uint16_t flag:3; 00407 uint16_t option:13; 00408 #else 00409 #if __BYTE_ORDER == __LITTLE_ENDIAN 00410 uint16_t option:13; 00411 uint16_t flag:3; 00412 #else 00413 #error Byte order not defined 00414 #endif 00415 #endif 00416 uint8_t data[0]; 00417 }; 00418 00419 00420 /*! \brief Definition of supported media formats (codecs) */ 00421 struct ast_format_list { 00422 int bits; /*!< bitmask value */ 00423 char *name; /*!< short name */ 00424 int samplespersecond; /*!< Number of samples per second (8000/16000) */ 00425 char *desc; /*!< Description */ 00426 int fr_len; /*!< Single frame length in bytes */ 00427 int min_ms; /*!< Min value */ 00428 int max_ms; /*!< Max value */ 00429 int inc_ms; /*!< Increment */ 00430 int def_ms; /*!< Default value */ 00431 unsigned int flags; /*!< Smoother flags */ 00432 int cur_ms; /*!< Current value */ 00433 }; 00434 00435 00436 /*! \brief Requests a frame to be allocated 00437 * 00438 * \param source 00439 * Request a frame be allocated. source is an optional source of the frame, 00440 * len is the requested length, or "0" if the caller will supply the buffer 00441 */ 00442 #if 0 /* Unimplemented */ 00443 struct ast_frame *ast_fralloc(char *source, int len); 00444 #endif 00445 00446 /*! 00447 * \brief Frees a frame or list of frames 00448 * 00449 * \param fr Frame to free, or head of list to free 00450 * \param cache Whether to consider this frame for frame caching 00451 */ 00452 void ast_frame_free(struct ast_frame *fr, int cache); 00453 00454 #define ast_frfree(fr) ast_frame_free(fr, 1) 00455 00456 /*! \brief Makes a frame independent of any static storage 00457 * \param fr frame to act upon 00458 * Take a frame, and if it's not been malloc'd, make a malloc'd copy 00459 * and if the data hasn't been malloced then make the 00460 * data malloc'd. If you need to store frames, say for queueing, then 00461 * you should call this function. 00462 * \return Returns a frame on success, NULL on error 00463 * \note This function may modify the frame passed to it, so you must 00464 * not assume the frame will be intact after the isolated frame has 00465 * been produced. In other words, calling this function on a frame 00466 * should be the last operation you do with that frame before freeing 00467 * it (or exiting the block, if the frame is on the stack.) 00468 */ 00469 struct ast_frame *ast_frisolate(struct ast_frame *fr); 00470 00471 /*! \brief Copies a frame 00472 * \param fr frame to copy 00473 * Duplicates a frame -- should only rarely be used, typically frisolate is good enough 00474 * \return Returns a frame on success, NULL on error 00475 */ 00476 struct ast_frame *ast_frdup(const struct ast_frame *fr); 00477 00478 void ast_swapcopy_samples(void *dst, const void *src, int samples); 00479 00480 /* Helpers for byteswapping native samples to/from 00481 little-endian and big-endian. */ 00482 #if __BYTE_ORDER == __LITTLE_ENDIAN 00483 #define ast_frame_byteswap_le(fr) do { ; } while(0) 00484 #define ast_frame_byteswap_be(fr) do { struct ast_frame *__f = (fr); ast_swapcopy_samples(__f->data.ptr, __f->data.ptr, __f->samples); } while(0) 00485 #else 00486 #define ast_frame_byteswap_le(fr) do { struct ast_frame *__f = (fr); ast_swapcopy_samples(__f->data.ptr, __f->data.ptr, __f->samples); } while(0) 00487 #define ast_frame_byteswap_be(fr) do { ; } while(0) 00488 #endif 00489 00490 00491 /*! \brief Get the name of a format 00492 * \param format id of format 00493 * \return A static string containing the name of the format or "unknown" if unknown. 00494 */ 00495 char* ast_getformatname(int format); 00496 00497 /*! \brief Get the names of a set of formats 00498 * \param buf a buffer for the output string 00499 * \param size size of buf (bytes) 00500 * \param format the format (combined IDs of codecs) 00501 * Prints a list of readable codec names corresponding to "format". 00502 * ex: for format=AST_FORMAT_GSM|AST_FORMAT_SPEEX|AST_FORMAT_ILBC it will return "0x602 (GSM|SPEEX|ILBC)" 00503 * \return The return value is buf. 00504 */ 00505 char* ast_getformatname_multiple(char *buf, size_t size, int format); 00506 00507 /*! 00508 * \brief Gets a format from a name. 00509 * \param name string of format 00510 * \return This returns the form of the format in binary on success, 0 on error. 00511 */ 00512 int ast_getformatbyname(const char *name); 00513 00514 /*! \brief Get a name from a format 00515 * Gets a name from a format 00516 * \param codec codec number (1,2,4,8,16,etc.) 00517 * \return This returns a static string identifying the format on success, 0 on error. 00518 */ 00519 char *ast_codec2str(int codec); 00520 00521 /*! \name AST_Smoother 00522 */ 00523 /*@{ */ 00524 /*! \page ast_smooth The AST Frame Smoother 00525 The ast_smoother interface was designed specifically 00526 to take frames of variant sizes and produce frames of a single expected 00527 size, precisely what you want to do. 00528 00529 The basic interface is: 00530 00531 - Initialize with ast_smoother_new() 00532 - Queue input frames with ast_smoother_feed() 00533 - Get output frames with ast_smoother_read() 00534 - when you're done, free the structure with ast_smoother_free() 00535 - Also see ast_smoother_test_flag(), ast_smoother_set_flags(), ast_smoother_get_flags(), ast_smoother_reset() 00536 */ 00537 struct ast_smoother; 00538 00539 struct ast_smoother *ast_smoother_new(int bytes); 00540 void ast_smoother_set_flags(struct ast_smoother *smoother, int flags); 00541 int ast_smoother_get_flags(struct ast_smoother *smoother); 00542 int ast_smoother_test_flag(struct ast_smoother *s, int flag); 00543 void ast_smoother_free(struct ast_smoother *s); 00544 void ast_smoother_reset(struct ast_smoother *s, int bytes); 00545 00546 /*! 00547 * \brief Reconfigure an existing smoother to output a different number of bytes per frame 00548 * \param s the smoother to reconfigure 00549 * \param bytes the desired number of bytes per output frame 00550 * \return nothing 00551 * 00552 */ 00553 void ast_smoother_reconfigure(struct ast_smoother *s, int bytes); 00554 00555 int __ast_smoother_feed(struct ast_smoother *s, struct ast_frame *f, int swap); 00556 struct ast_frame *ast_smoother_read(struct ast_smoother *s); 00557 #define ast_smoother_feed(s,f) __ast_smoother_feed(s, f, 0) 00558 #if __BYTE_ORDER == __LITTLE_ENDIAN 00559 #define ast_smoother_feed_be(s,f) __ast_smoother_feed(s, f, 1) 00560 #define ast_smoother_feed_le(s,f) __ast_smoother_feed(s, f, 0) 00561 #else 00562 #define ast_smoother_feed_be(s,f) __ast_smoother_feed(s, f, 0) 00563 #define ast_smoother_feed_le(s,f) __ast_smoother_feed(s, f, 1) 00564 #endif 00565 /*@} Doxygen marker */ 00566 00567 struct ast_format_list *ast_get_format_list_index(int index); 00568 struct ast_format_list *ast_get_format_list(size_t *size); 00569 void ast_frame_dump(const char *name, struct ast_frame *f, char *prefix); 00570 00571 /*! \page AudioCodecPref Audio Codec Preferences 00572 00573 In order to negotiate audio codecs in the order they are configured 00574 in <channel>.conf for a device, we set up codec preference lists 00575 in addition to the codec capabilities setting. The capabilities 00576 setting is a bitmask of audio and video codecs with no internal 00577 order. This will reflect the offer given to the other side, where 00578 the prefered codecs will be added to the top of the list in the 00579 order indicated by the "allow" lines in the device configuration. 00580 00581 Video codecs are not included in the preference lists since they 00582 can't be transcoded and we just have to pick whatever is supported 00583 */ 00584 00585 /*! 00586 *\brief Initialize an audio codec preference to "no preference". 00587 * \arg \ref AudioCodecPref 00588 */ 00589 void ast_codec_pref_init(struct ast_codec_pref *pref); 00590 00591 /*! 00592 * \brief Codec located at a particular place in the preference index. 00593 * \arg \ref AudioCodecPref 00594 */ 00595 int ast_codec_pref_index(struct ast_codec_pref *pref, int index); 00596 00597 /*! \brief Remove audio a codec from a preference list */ 00598 void ast_codec_pref_remove(struct ast_codec_pref *pref, int format); 00599 00600 /*! \brief Append a audio codec to a preference list, removing it first if it was already there 00601 */ 00602 int ast_codec_pref_append(struct ast_codec_pref *pref, int format); 00603 00604 /*! \brief Prepend an audio codec to a preference list, removing it first if it was already there 00605 */ 00606 void ast_codec_pref_prepend(struct ast_codec_pref *pref, int format, int only_if_existing); 00607 00608 /*! \brief Select the best audio format according to preference list from supplied options. 00609 If "find_best" is non-zero then if nothing is found, the "Best" format of 00610 the format list is selected, otherwise 0 is returned. */ 00611 int ast_codec_choose(struct ast_codec_pref *pref, int formats, int find_best); 00612 00613 /*! \brief Set packet size for codec 00614 */ 00615 int ast_codec_pref_setsize(struct ast_codec_pref *pref, int format, int framems); 00616 00617 /*! \brief Get packet size for codec 00618 */ 00619 struct ast_format_list ast_codec_pref_getsize(struct ast_codec_pref *pref, int format); 00620 00621 /*! \brief Parse an "allow" or "deny" line in a channel or device configuration 00622 and update the capabilities mask and pref if provided. 00623 Video codecs are not added to codec preference lists, since we can not transcode 00624 \return Returns number of errors encountered during parsing 00625 */ 00626 int ast_parse_allow_disallow(struct ast_codec_pref *pref, int *mask, const char *list, int allowing); 00627 00628 /*! \brief Dump audio codec preference list into a string */ 00629 int ast_codec_pref_string(struct ast_codec_pref *pref, char *buf, size_t size); 00630 00631 /*! \brief Shift an audio codec preference list up or down 65 bytes so that it becomes an ASCII string */ 00632 void ast_codec_pref_convert(struct ast_codec_pref *pref, char *buf, size_t size, int right); 00633 00634 /*! \brief Returns the number of samples contained in the frame */ 00635 int ast_codec_get_samples(struct ast_frame *f); 00636 00637 /*! \brief Returns the number of bytes for the number of samples of the given format */ 00638 int ast_codec_get_len(int format, int samples); 00639 00640 /*! \brief Appends a frame to the end of a list of frames, truncating the maximum length of the list */ 00641 struct ast_frame *ast_frame_enqueue(struct ast_frame *head, struct ast_frame *f, int maxlen, int dupe); 00642 00643 00644 /*! \brief Gets duration in ms of interpolation frame for a format */ 00645 static inline int ast_codec_interp_len(int format) 00646 { 00647 return (format == AST_FORMAT_ILBC) ? 30 : 20; 00648 } 00649 00650 /*! 00651 \brief Adjusts the volume of the audio samples contained in a frame. 00652 \param f The frame containing the samples (must be AST_FRAME_VOICE and AST_FORMAT_SLINEAR) 00653 \param adjustment The number of dB to adjust up or down. 00654 \return 0 for success, non-zero for an error 00655 */ 00656 int ast_frame_adjust_volume(struct ast_frame *f, int adjustment); 00657 00658 /*! 00659 \brief Sums two frames of audio samples. 00660 \param f1 The first frame (which will contain the result) 00661 \param f2 The second frame 00662 \return 0 for success, non-zero for an error 00663 00664 The frames must be AST_FRAME_VOICE and must contain AST_FORMAT_SLINEAR samples, 00665 and must contain the same number of samples. 00666 */ 00667 int ast_frame_slinear_sum(struct ast_frame *f1, struct ast_frame *f2); 00668 00669 /*! 00670 * \brief Get the sample rate for a given format. 00671 */ 00672 static force_inline int ast_format_rate(int format) 00673 { 00674 if (format == AST_FORMAT_G722 || format == AST_FORMAT_SLINEAR16) 00675 return 16000; 00676 00677 return 8000; 00678 } 00679 00680 #if defined(__cplusplus) || defined(c_plusplus) 00681 } 00682 #endif 00683 00684 #endif /* _ASTERISK_FRAME_H */