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/types.h> 00033 #include <sys/time.h> 00034 00035 #include "asterisk/compiler.h" 00036 #include "asterisk/endian.h" 00037 #include "asterisk/linkedlists.h" 00038 00039 struct ast_codec_pref { 00040 char order[32]; 00041 char framing[32]; 00042 }; 00043 00044 /*! \page Def_Frame AST Multimedia and signalling frames 00045 \section Def_AstFrame What is an ast_frame ? 00046 A frame of data read used to communicate between 00047 between channels and applications. 00048 Frames are divided into frame types and subclasses. 00049 00050 \par Frame types 00051 \arg \b VOICE: Voice data, subclass is codec (AST_FORMAT_*) 00052 \arg \b VIDEO: Video data, subclass is codec (AST_FORMAT_*) 00053 \arg \b DTMF: A DTMF digit, subclass is the digit 00054 \arg \b IMAGE: Image transport, mostly used in IAX 00055 \arg \b TEXT: Text messages 00056 \arg \b HTML: URL's and web pages 00057 \arg \b MODEM: Modulated data encodings, such as T.38 and V.150 00058 \arg \b IAX: Private frame type for the IAX protocol 00059 \arg \b CNG: Comfort noice frames 00060 \arg \b CONTROL: A control frame, subclass defined as AST_CONTROL_ 00061 \arg \b NULL: Empty, useless frame 00062 00063 \par Files 00064 \arg frame.h Definitions 00065 \arg frame.c Function library 00066 \arg \ref Def_Channel Asterisk channels 00067 \section Def_ControlFrame Control Frames 00068 Control frames send signalling information between channels 00069 and devices. They are prefixed with AST_CONTROL_, like AST_CONTROL_FRAME_HANGUP 00070 \arg \b HANGUP The other end has hungup 00071 \arg \b RING Local ring 00072 \arg \b RINGING The other end is ringing 00073 \arg \b ANSWER The other end has answered 00074 \arg \b BUSY Remote end is busy 00075 \arg \b TAKEOFFHOOK Make it go off hook (what's "it" ? ) 00076 \arg \b OFFHOOK Line is off hook 00077 \arg \b CONGESTION Congestion (circuit is busy, not available) 00078 \arg \b FLASH Other end sends flash hook 00079 \arg \b WINK Other end sends wink 00080 \arg \b OPTION Send low-level option 00081 \arg \b RADIO_KEY Key radio (see app_rpt.c) 00082 \arg \b RADIO_UNKEY Un-key radio (see app_rpt.c) 00083 \arg \b PROGRESS Other end indicates call progress 00084 \arg \b PROCEEDING Indicates proceeding 00085 \arg \b HOLD Call is placed on hold 00086 \arg \b UNHOLD Call is back from hold 00087 \arg \b VIDUPDATE Video update requested 00088 \arg \b SRCUPDATE The source of media has changed 00089 00090 */ 00091 00092 /*! 00093 * \brief Frame types 00094 * 00095 * \note It is important that the values of each frame type are never changed, 00096 * because it will break backwards compatability with older versions. 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 /*! This frame came from a translator and is still the original frame. 00131 * The translator can not be free'd if the frame inside of it still has 00132 * this flag set. */ 00133 AST_FRFLAG_FROM_TRANSLATOR = (1 << 1), 00134 /*! This frame came from a dsp and is still the original frame. 00135 * The dsp cannot be free'd if the frame inside of it still has 00136 * this flag set. */ 00137 AST_FRFLAG_FROM_DSP = (1 << 2), 00138 /*! This frame came from a filestream and is still the original frame. 00139 * The filestream cannot be free'd if the frame inside of it still has 00140 * this flag set. */ 00141 AST_FRFLAG_FROM_FILESTREAM = (1 << 3), 00142 }; 00143 00144 /*! \brief Data structure associated with a single frame of data 00145 */ 00146 struct ast_frame { 00147 /*! Kind of frame */ 00148 enum ast_frame_type frametype; 00149 /*! Subclass, frame dependent */ 00150 int subclass; 00151 /*! Length of data */ 00152 int datalen; 00153 /*! Number of 8khz samples in this frame */ 00154 int samples; 00155 /*! Was the data malloc'd? i.e. should we free it when we discard the frame? */ 00156 int mallocd; 00157 /*! The number of bytes allocated for a malloc'd frame header */ 00158 size_t mallocd_hdr_len; 00159 /*! How many bytes exist _before_ "data" that can be used if needed */ 00160 int offset; 00161 /*! Optional source of frame for debugging */ 00162 const char *src; 00163 /*! Pointer to actual data */ 00164 void *data; 00165 /*! Global delivery time */ 00166 struct timeval delivery; 00167 /*! For placing in a linked list */ 00168 AST_LIST_ENTRY(ast_frame) frame_list; 00169 /*! Misc. frame flags */ 00170 unsigned int flags; 00171 /*! Timestamp in milliseconds */ 00172 long ts; 00173 /*! Length in milliseconds */ 00174 long len; 00175 /*! Sequence number */ 00176 int seqno; 00177 }; 00178 00179 /*! 00180 * Set the various field of a frame to point to a buffer. 00181 * Typically you set the base address of the buffer, the offset as 00182 * AST_FRIENDLY_OFFSET, and the datalen as the amount of bytes queued. 00183 * The remaining things (to be done manually) is set the number of 00184 * samples, which cannot be derived from the datalen unless you know 00185 * the number of bits per sample. 00186 */ 00187 #define AST_FRAME_SET_BUFFER(fr, _base, _ofs, _datalen) \ 00188 { \ 00189 (fr)->data = (char *)_base + (_ofs); \ 00190 (fr)->offset = (_ofs); \ 00191 (fr)->datalen = (_datalen); \ 00192 } 00193 00194 /*! Queueing a null frame is fairly common, so we declare a global null frame object 00195 for this purpose instead of having to declare one on the stack */ 00196 extern struct ast_frame ast_null_frame; 00197 00198 #define AST_FRIENDLY_OFFSET 64 /*! It's polite for a a new frame to 00199 have this number of bytes for additional 00200 headers. */ 00201 #define AST_MIN_OFFSET 32 /*! Make sure we keep at least this much handy */ 00202 00203 /*! Need the header be free'd? */ 00204 #define AST_MALLOCD_HDR (1 << 0) 00205 /*! Need the data be free'd? */ 00206 #define AST_MALLOCD_DATA (1 << 1) 00207 /*! Need the source be free'd? (haha!) */ 00208 #define AST_MALLOCD_SRC (1 << 2) 00209 00210 /* MODEM subclasses */ 00211 /*! T.38 Fax-over-IP */ 00212 #define AST_MODEM_T38 1 00213 /*! V.150 Modem-over-IP */ 00214 #define AST_MODEM_V150 2 00215 00216 /* HTML subclasses */ 00217 /*! Sending a URL */ 00218 #define AST_HTML_URL 1 00219 /*! Data frame */ 00220 #define AST_HTML_DATA 2 00221 /*! Beginning frame */ 00222 #define AST_HTML_BEGIN 4 00223 /*! End frame */ 00224 #define AST_HTML_END 8 00225 /*! Load is complete */ 00226 #define AST_HTML_LDCOMPLETE 16 00227 /*! Peer is unable to support HTML */ 00228 #define AST_HTML_NOSUPPORT 17 00229 /*! Send URL, and track */ 00230 #define AST_HTML_LINKURL 18 00231 /*! No more HTML linkage */ 00232 #define AST_HTML_UNLINK 19 00233 /*! Reject link request */ 00234 #define AST_HTML_LINKREJECT 20 00235 00236 /* Data formats for capabilities and frames alike */ 00237 /*! G.723.1 compression */ 00238 #define AST_FORMAT_G723_1 (1 << 0) 00239 /*! GSM compression */ 00240 #define AST_FORMAT_GSM (1 << 1) 00241 /*! Raw mu-law data (G.711) */ 00242 #define AST_FORMAT_ULAW (1 << 2) 00243 /*! Raw A-law data (G.711) */ 00244 #define AST_FORMAT_ALAW (1 << 3) 00245 /*! ADPCM (G.726, 32kbps, AAL2 codeword packing) */ 00246 #define AST_FORMAT_G726_AAL2 (1 << 4) 00247 /*! ADPCM (IMA) */ 00248 #define AST_FORMAT_ADPCM (1 << 5) 00249 /*! Raw 16-bit Signed Linear (8000 Hz) PCM */ 00250 #define AST_FORMAT_SLINEAR (1 << 6) 00251 /*! LPC10, 180 samples/frame */ 00252 #define AST_FORMAT_LPC10 (1 << 7) 00253 /*! G.729A audio */ 00254 #define AST_FORMAT_G729A (1 << 8) 00255 /*! SpeeX Free Compression */ 00256 #define AST_FORMAT_SPEEX (1 << 9) 00257 /*! iLBC Free Compression */ 00258 #define AST_FORMAT_ILBC (1 << 10) 00259 /*! ADPCM (G.726, 32kbps, RFC3551 codeword packing) */ 00260 #define AST_FORMAT_G726 (1 << 11) 00261 /*! G.722 */ 00262 #define AST_FORMAT_G722 (1 << 12) 00263 /*! Unsupported audio bits */ 00264 #define AST_FORMAT_AUDIO_UNDEFINED ((1 << 13) | (1 << 14) | (1 << 15)) 00265 /*! Maximum audio format */ 00266 #define AST_FORMAT_MAX_AUDIO (1 << 15) 00267 /*! Maximum audio mask */ 00268 #define AST_FORMAT_AUDIO_MASK ((1 << 16)-1) 00269 /*! JPEG Images */ 00270 #define AST_FORMAT_JPEG (1 << 16) 00271 /*! PNG Images */ 00272 #define AST_FORMAT_PNG (1 << 17) 00273 /*! H.261 Video */ 00274 #define AST_FORMAT_H261 (1 << 18) 00275 /*! H.263 Video */ 00276 #define AST_FORMAT_H263 (1 << 19) 00277 /*! H.263+ Video */ 00278 #define AST_FORMAT_H263_PLUS (1 << 20) 00279 /*! H.264 Video */ 00280 #define AST_FORMAT_H264 (1 << 21) 00281 /*! Maximum video format */ 00282 #define AST_FORMAT_MAX_VIDEO (1 << 24) 00283 #define AST_FORMAT_VIDEO_MASK (((1 << 25)-1) & ~(AST_FORMAT_AUDIO_MASK)) 00284 00285 enum ast_control_frame_type { 00286 AST_CONTROL_HANGUP = 1, /*!< Other end has hungup */ 00287 AST_CONTROL_RING = 2, /*!< Local ring */ 00288 AST_CONTROL_RINGING = 3, /*!< Remote end is ringing */ 00289 AST_CONTROL_ANSWER = 4, /*!< Remote end has answered */ 00290 AST_CONTROL_BUSY = 5, /*!< Remote end is busy */ 00291 AST_CONTROL_TAKEOFFHOOK = 6, /*!< Make it go off hook */ 00292 AST_CONTROL_OFFHOOK = 7, /*!< Line is off hook */ 00293 AST_CONTROL_CONGESTION = 8, /*!< Congestion (circuits busy) */ 00294 AST_CONTROL_FLASH = 9, /*!< Flash hook */ 00295 AST_CONTROL_WINK = 10, /*!< Wink */ 00296 AST_CONTROL_OPTION = 11, /*!< Set a low-level option */ 00297 AST_CONTROL_RADIO_KEY = 12, /*!< Key Radio */ 00298 AST_CONTROL_RADIO_UNKEY = 13, /*!< Un-Key Radio */ 00299 AST_CONTROL_PROGRESS = 14, /*!< Indicate PROGRESS */ 00300 AST_CONTROL_PROCEEDING = 15, /*!< Indicate CALL PROCEEDING */ 00301 AST_CONTROL_HOLD = 16, /*!< Indicate call is placed on hold */ 00302 AST_CONTROL_UNHOLD = 17, /*!< Indicate call is left from hold */ 00303 AST_CONTROL_VIDUPDATE = 18, /*!< Indicate video frame update */ 00304 AST_CONTROL_ATXFERCMD = 19, /*!< AMI triggered attended transfer */ 00305 AST_CONTROL_SRCUPDATE = 20, /*!< Indicate source of media has changed */ 00306 }; 00307 00308 #define AST_SMOOTHER_FLAG_G729 (1 << 0) 00309 #define AST_SMOOTHER_FLAG_BE (1 << 1) 00310 00311 /* Option identifiers and flags */ 00312 #define AST_OPTION_FLAG_REQUEST 0 00313 #define AST_OPTION_FLAG_ACCEPT 1 00314 #define AST_OPTION_FLAG_REJECT 2 00315 #define AST_OPTION_FLAG_QUERY 4 00316 #define AST_OPTION_FLAG_ANSWER 5 00317 #define AST_OPTION_FLAG_WTF 6 00318 00319 /*! Verify touchtones by muting audio transmission 00320 (and reception) and verify the tone is still present */ 00321 #define AST_OPTION_TONE_VERIFY 1 00322 00323 /*! Put a compatible channel into TDD (TTY for the hearing-impared) mode */ 00324 #define AST_OPTION_TDD 2 00325 00326 /*! Relax the parameters for DTMF reception (mainly for radio use) */ 00327 #define AST_OPTION_RELAXDTMF 3 00328 00329 /*! Set (or clear) Audio (Not-Clear) Mode */ 00330 #define AST_OPTION_AUDIO_MODE 4 00331 00332 /*! Set channel transmit gain 00333 * Option data is a single signed char 00334 representing number of decibels (dB) 00335 to set gain to (on top of any gain 00336 specified in channel driver) 00337 */ 00338 #define AST_OPTION_TXGAIN 5 00339 00340 /*! Set channel receive gain 00341 * Option data is a single signed char 00342 representing number of decibels (dB) 00343 to set gain to (on top of any gain 00344 specified in channel driver) 00345 */ 00346 #define AST_OPTION_RXGAIN 6 00347 00348 /* set channel into "Operator Services" mode */ 00349 #define AST_OPTION_OPRMODE 7 00350 00351 /*! Explicitly enable or disable echo cancelation for the given channel */ 00352 #define AST_OPTION_ECHOCAN 8 00353 00354 struct oprmode { 00355 struct ast_channel *peer; 00356 int mode; 00357 } ; 00358 00359 struct ast_option_header { 00360 /* Always keep in network byte order */ 00361 #if __BYTE_ORDER == __BIG_ENDIAN 00362 uint16_t flag:3; 00363 uint16_t option:13; 00364 #else 00365 #if __BYTE_ORDER == __LITTLE_ENDIAN 00366 uint16_t option:13; 00367 uint16_t flag:3; 00368 #else 00369 #error Byte order not defined 00370 #endif 00371 #endif 00372 uint8_t data[0]; 00373 }; 00374 00375 00376 /*! \brief Definition of supported media formats (codecs) */ 00377 struct ast_format_list { 00378 int visible; /*!< Can we see this entry */ 00379 int bits; /*!< bitmask value */ 00380 char *name; /*!< short name */ 00381 char *desc; /*!< Description */ 00382 int fr_len; /*!< Single frame length in bytes */ 00383 int min_ms; /*!< Min value */ 00384 int max_ms; /*!< Max value */ 00385 int inc_ms; /*!< Increment */ 00386 int def_ms; /*!< Default value */ 00387 unsigned int flags; /*!< Smoother flags */ 00388 int cur_ms; /*!< Current value */ 00389 }; 00390 00391 00392 /*! \brief Requests a frame to be allocated 00393 * 00394 * \param source 00395 * Request a frame be allocated. source is an optional source of the frame, 00396 * len is the requested length, or "0" if the caller will supply the buffer 00397 */ 00398 #if 0 /* Unimplemented */ 00399 struct ast_frame *ast_fralloc(char *source, int len); 00400 #endif 00401 00402 /*! 00403 * \brief Frees a frame 00404 * 00405 * \param fr Frame to free 00406 * \param cache Whether to consider this frame for frame caching 00407 */ 00408 void ast_frame_free(struct ast_frame *fr, int cache); 00409 00410 #define ast_frfree(fr) ast_frame_free(fr, 1) 00411 00412 /*! \brief Makes a frame independent of any static storage 00413 * \param fr frame to act upon 00414 * Take a frame, and if it's not been malloc'd, make a malloc'd copy 00415 * and if the data hasn't been malloced then make the 00416 * data malloc'd. If you need to store frames, say for queueing, then 00417 * you should call this function. 00418 * \return Returns a frame on success, NULL on error 00419 */ 00420 struct ast_frame *ast_frisolate(struct ast_frame *fr); 00421 00422 /*! \brief Copies a frame 00423 * \param fr frame to copy 00424 * Duplicates a frame -- should only rarely be used, typically frisolate is good enough 00425 * \return Returns a frame on success, NULL on error 00426 */ 00427 struct ast_frame *ast_frdup(const struct ast_frame *fr); 00428 00429 void ast_swapcopy_samples(void *dst, const void *src, int samples); 00430 00431 /* Helpers for byteswapping native samples to/from 00432 little-endian and big-endian. */ 00433 #if __BYTE_ORDER == __LITTLE_ENDIAN 00434 #define ast_frame_byteswap_le(fr) do { ; } while(0) 00435 #define ast_frame_byteswap_be(fr) do { struct ast_frame *__f = (fr); ast_swapcopy_samples(__f->data, __f->data, __f->samples); } while(0) 00436 #else 00437 #define ast_frame_byteswap_le(fr) do { struct ast_frame *__f = (fr); ast_swapcopy_samples(__f->data, __f->data, __f->samples); } while(0) 00438 #define ast_frame_byteswap_be(fr) do { ; } while(0) 00439 #endif 00440 00441 00442 /*! \brief Get the name of a format 00443 * \param format id of format 00444 * \return A static string containing the name of the format or "unknown" if unknown. 00445 */ 00446 char* ast_getformatname(int format); 00447 00448 /*! \brief Get the names of a set of formats 00449 * \param buf a buffer for the output string 00450 * \param size size of buf (bytes) 00451 * \param format the format (combined IDs of codecs) 00452 * Prints a list of readable codec names corresponding to "format". 00453 * ex: for format=AST_FORMAT_GSM|AST_FORMAT_SPEEX|AST_FORMAT_ILBC it will return "0x602 (GSM|SPEEX|ILBC)" 00454 * \return The return value is buf. 00455 */ 00456 char* ast_getformatname_multiple(char *buf, size_t size, int format); 00457 00458 /*! 00459 * \brief Gets a format from a name. 00460 * \param name string of format 00461 * \return This returns the form of the format in binary on success, 0 on error. 00462 */ 00463 int ast_getformatbyname(const char *name); 00464 00465 /*! \brief Get a name from a format 00466 * Gets a name from a format 00467 * \param codec codec number (1,2,4,8,16,etc.) 00468 * \return This returns a static string identifying the format on success, 0 on error. 00469 */ 00470 char *ast_codec2str(int codec); 00471 00472 struct ast_smoother; 00473 00474 struct ast_format_list *ast_get_format_list_index(int index); 00475 struct ast_format_list *ast_get_format_list(size_t *size); 00476 struct ast_smoother *ast_smoother_new(int bytes); 00477 void ast_smoother_set_flags(struct ast_smoother *smoother, int flags); 00478 int ast_smoother_get_flags(struct ast_smoother *smoother); 00479 int ast_smoother_test_flag(struct ast_smoother *s, int flag); 00480 void ast_smoother_free(struct ast_smoother *s); 00481 void ast_smoother_reset(struct ast_smoother *s, int bytes); 00482 00483 /*! 00484 * \brief Reconfigure an existing smoother to output a different number of bytes per frame 00485 * \param s the smoother to reconfigure 00486 * \param bytes the desired number of bytes per output frame 00487 * \return nothing 00488 * 00489 */ 00490 void ast_smoother_reconfigure(struct ast_smoother *s, int bytes); 00491 00492 int __ast_smoother_feed(struct ast_smoother *s, struct ast_frame *f, int swap); 00493 struct ast_frame *ast_smoother_read(struct ast_smoother *s); 00494 #define ast_smoother_feed(s,f) __ast_smoother_feed(s, f, 0) 00495 #if __BYTE_ORDER == __LITTLE_ENDIAN 00496 #define ast_smoother_feed_be(s,f) __ast_smoother_feed(s, f, 1) 00497 #define ast_smoother_feed_le(s,f) __ast_smoother_feed(s, f, 0) 00498 #else 00499 #define ast_smoother_feed_be(s,f) __ast_smoother_feed(s, f, 0) 00500 #define ast_smoother_feed_le(s,f) __ast_smoother_feed(s, f, 1) 00501 #endif 00502 00503 void ast_frame_dump(const char *name, struct ast_frame *f, char *prefix); 00504 00505 /*! \page AudioCodecPref Audio Codec Preferences 00506 In order to negotiate audio codecs in the order they are configured 00507 in <channel>.conf for a device, we set up codec preference lists 00508 in addition to the codec capabilities setting. The capabilities 00509 setting is a bitmask of audio and video codecs with no internal 00510 order. This will reflect the offer given to the other side, where 00511 the prefered codecs will be added to the top of the list in the 00512 order indicated by the "allow" lines in the device configuration. 00513 00514 Video codecs are not included in the preference lists since they 00515 can't be transcoded and we just have to pick whatever is supported 00516 */ 00517 00518 /*! \brief Initialize an audio codec preference to "no preference" See \ref AudioCodecPref */ 00519 void ast_codec_pref_init(struct ast_codec_pref *pref); 00520 00521 /*! \brief Codec located at a particular place in the preference index See \ref AudioCodecPref */ 00522 int ast_codec_pref_index(struct ast_codec_pref *pref, int index); 00523 00524 /*! \brief Remove audio a codec from a preference list */ 00525 void ast_codec_pref_remove(struct ast_codec_pref *pref, int format); 00526 00527 /*! \brief Append a audio codec to a preference list, removing it first if it was already there 00528 */ 00529 int ast_codec_pref_append(struct ast_codec_pref *pref, int format); 00530 00531 /*! \brief Prepend an audio codec to a preference list, removing it first if it was already there 00532 */ 00533 void ast_codec_pref_prepend(struct ast_codec_pref *pref, int format, int only_if_existing); 00534 00535 /*! \brief Select the best audio format according to preference list from supplied options. 00536 If "find_best" is non-zero then if nothing is found, the "Best" format of 00537 the format list is selected, otherwise 0 is returned. */ 00538 int ast_codec_choose(struct ast_codec_pref *pref, int formats, int find_best); 00539 00540 /*! \brief Set packet size for codec 00541 */ 00542 int ast_codec_pref_setsize(struct ast_codec_pref *pref, int format, int framems); 00543 00544 /*! \brief Get packet size for codec 00545 */ 00546 struct ast_format_list ast_codec_pref_getsize(struct ast_codec_pref *pref, int format); 00547 00548 /*! \brief Parse an "allow" or "deny" line in a channel or device configuration 00549 and update the capabilities mask and pref if provided. 00550 Video codecs are not added to codec preference lists, since we can not transcode 00551 */ 00552 void ast_parse_allow_disallow(struct ast_codec_pref *pref, int *mask, const char *list, int allowing); 00553 00554 /*! \brief Dump audio codec preference list into a string */ 00555 int ast_codec_pref_string(struct ast_codec_pref *pref, char *buf, size_t size); 00556 00557 /*! \brief Shift an audio codec preference list up or down 65 bytes so that it becomes an ASCII string */ 00558 void ast_codec_pref_convert(struct ast_codec_pref *pref, char *buf, size_t size, int right); 00559 00560 /*! \brief Returns the number of samples contained in the frame */ 00561 int ast_codec_get_samples(struct ast_frame *f); 00562 00563 /*! \brief Returns the number of bytes for the number of samples of the given format */ 00564 int ast_codec_get_len(int format, int samples); 00565 00566 /*! \brief Appends a frame to the end of a list of frames, truncating the maximum length of the list */ 00567 struct ast_frame *ast_frame_enqueue(struct ast_frame *head, struct ast_frame *f, int maxlen, int dupe); 00568 00569 00570 /*! \brief Gets duration in ms of interpolation frame for a format */ 00571 static inline int ast_codec_interp_len(int format) 00572 { 00573 return (format == AST_FORMAT_ILBC) ? 30 : 20; 00574 } 00575 00576 /*! 00577 \brief Adjusts the volume of the audio samples contained in a frame. 00578 \param f The frame containing the samples (must be AST_FRAME_VOICE and AST_FORMAT_SLINEAR) 00579 \param adjustment The number of dB to adjust up or down. 00580 \return 0 for success, non-zero for an error 00581 */ 00582 int ast_frame_adjust_volume(struct ast_frame *f, int adjustment); 00583 00584 /*! 00585 \brief Sums two frames of audio samples. 00586 \param f1 The first frame (which will contain the result) 00587 \param f2 The second frame 00588 \return 0 for success, non-zero for an error 00589 00590 The frames must be AST_FRAME_VOICE and must contain AST_FORMAT_SLINEAR samples, 00591 and must contain the same number of samples. 00592 */ 00593 int ast_frame_slinear_sum(struct ast_frame *f1, struct ast_frame *f2); 00594 00595 /*! 00596 * \brief Get the sample rate for a given format. 00597 */ 00598 static force_inline int ast_format_rate(int format) 00599 { 00600 if (format == AST_FORMAT_G722) 00601 return 16000; 00602 00603 return 8000; 00604 } 00605 00606 #if defined(__cplusplus) || defined(c_plusplus) 00607 } 00608 #endif 00609 00610 #endif /* _ASTERISK_FRAME_H */