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 }; 00135 00136 /*! \brief Data structure associated with a single frame of data 00137 */ 00138 struct ast_frame { 00139 /*! Kind of frame */ 00140 enum ast_frame_type frametype; 00141 /*! Subclass, frame dependent */ 00142 int subclass; 00143 /*! Length of data */ 00144 int datalen; 00145 /*! Number of 8khz samples in this frame */ 00146 int samples; 00147 /*! Was the data malloc'd? i.e. should we free it when we discard the frame? */ 00148 int mallocd; 00149 /*! The number of bytes allocated for a malloc'd frame header */ 00150 size_t mallocd_hdr_len; 00151 /*! How many bytes exist _before_ "data" that can be used if needed */ 00152 int offset; 00153 /*! Optional source of frame for debugging */ 00154 const char *src; 00155 /*! Pointer to actual data */ 00156 void *data; 00157 /*! Global delivery time */ 00158 struct timeval delivery; 00159 /*! For placing in a linked list */ 00160 AST_LIST_ENTRY(ast_frame) frame_list; 00161 /*! Misc. frame flags */ 00162 unsigned int flags; 00163 /*! Timestamp in milliseconds */ 00164 long ts; 00165 /*! Length in milliseconds */ 00166 long len; 00167 /*! Sequence number */ 00168 int seqno; 00169 }; 00170 00171 /*! 00172 * Set the various field of a frame to point to a buffer. 00173 * Typically you set the base address of the buffer, the offset as 00174 * AST_FRIENDLY_OFFSET, and the datalen as the amount of bytes queued. 00175 * The remaining things (to be done manually) is set the number of 00176 * samples, which cannot be derived from the datalen unless you know 00177 * the number of bits per sample. 00178 */ 00179 #define AST_FRAME_SET_BUFFER(fr, _base, _ofs, _datalen) \ 00180 { \ 00181 (fr)->data = (char *)_base + (_ofs); \ 00182 (fr)->offset = (_ofs); \ 00183 (fr)->datalen = (_datalen); \ 00184 } 00185 00186 /*! Queueing a null frame is fairly common, so we declare a global null frame object 00187 for this purpose instead of having to declare one on the stack */ 00188 extern struct ast_frame ast_null_frame; 00189 00190 #define AST_FRIENDLY_OFFSET 64 /*! It's polite for a a new frame to 00191 have this number of bytes for additional 00192 headers. */ 00193 #define AST_MIN_OFFSET 32 /*! Make sure we keep at least this much handy */ 00194 00195 /*! Need the header be free'd? */ 00196 #define AST_MALLOCD_HDR (1 << 0) 00197 /*! Need the data be free'd? */ 00198 #define AST_MALLOCD_DATA (1 << 1) 00199 /*! Need the source be free'd? (haha!) */ 00200 #define AST_MALLOCD_SRC (1 << 2) 00201 00202 /* MODEM subclasses */ 00203 /*! T.38 Fax-over-IP */ 00204 #define AST_MODEM_T38 1 00205 /*! V.150 Modem-over-IP */ 00206 #define AST_MODEM_V150 2 00207 00208 /* HTML subclasses */ 00209 /*! Sending a URL */ 00210 #define AST_HTML_URL 1 00211 /*! Data frame */ 00212 #define AST_HTML_DATA 2 00213 /*! Beginning frame */ 00214 #define AST_HTML_BEGIN 4 00215 /*! End frame */ 00216 #define AST_HTML_END 8 00217 /*! Load is complete */ 00218 #define AST_HTML_LDCOMPLETE 16 00219 /*! Peer is unable to support HTML */ 00220 #define AST_HTML_NOSUPPORT 17 00221 /*! Send URL, and track */ 00222 #define AST_HTML_LINKURL 18 00223 /*! No more HTML linkage */ 00224 #define AST_HTML_UNLINK 19 00225 /*! Reject link request */ 00226 #define AST_HTML_LINKREJECT 20 00227 00228 /* Data formats for capabilities and frames alike */ 00229 /*! G.723.1 compression */ 00230 #define AST_FORMAT_G723_1 (1 << 0) 00231 /*! GSM compression */ 00232 #define AST_FORMAT_GSM (1 << 1) 00233 /*! Raw mu-law data (G.711) */ 00234 #define AST_FORMAT_ULAW (1 << 2) 00235 /*! Raw A-law data (G.711) */ 00236 #define AST_FORMAT_ALAW (1 << 3) 00237 /*! ADPCM (G.726, 32kbps, AAL2 codeword packing) */ 00238 #define AST_FORMAT_G726_AAL2 (1 << 4) 00239 /*! ADPCM (IMA) */ 00240 #define AST_FORMAT_ADPCM (1 << 5) 00241 /*! Raw 16-bit Signed Linear (8000 Hz) PCM */ 00242 #define AST_FORMAT_SLINEAR (1 << 6) 00243 /*! LPC10, 180 samples/frame */ 00244 #define AST_FORMAT_LPC10 (1 << 7) 00245 /*! G.729A audio */ 00246 #define AST_FORMAT_G729A (1 << 8) 00247 /*! SpeeX Free Compression */ 00248 #define AST_FORMAT_SPEEX (1 << 9) 00249 /*! iLBC Free Compression */ 00250 #define AST_FORMAT_ILBC (1 << 10) 00251 /*! ADPCM (G.726, 32kbps, RFC3551 codeword packing) */ 00252 #define AST_FORMAT_G726 (1 << 11) 00253 /*! G.722 */ 00254 #define AST_FORMAT_G722 (1 << 12) 00255 /*! Maximum audio format */ 00256 #define AST_FORMAT_MAX_AUDIO (1 << 15) 00257 /*! Maximum audio mask */ 00258 #define AST_FORMAT_AUDIO_MASK ((1 << 16)-1) 00259 /*! JPEG Images */ 00260 #define AST_FORMAT_JPEG (1 << 16) 00261 /*! PNG Images */ 00262 #define AST_FORMAT_PNG (1 << 17) 00263 /*! H.261 Video */ 00264 #define AST_FORMAT_H261 (1 << 18) 00265 /*! H.263 Video */ 00266 #define AST_FORMAT_H263 (1 << 19) 00267 /*! H.263+ Video */ 00268 #define AST_FORMAT_H263_PLUS (1 << 20) 00269 /*! H.264 Video */ 00270 #define AST_FORMAT_H264 (1 << 21) 00271 /*! MPEG4 Video */ 00272 #define AST_FORMAT_MP4_VIDEO (1 << 22) 00273 /*! Maximum video format */ 00274 #define AST_FORMAT_MAX_VIDEO (1 << 24) 00275 #define AST_FORMAT_VIDEO_MASK (((1 << 25)-1) & ~(AST_FORMAT_AUDIO_MASK)) 00276 00277 enum ast_control_frame_type { 00278 AST_CONTROL_HANGUP = 1, /*!< Other end has hungup */ 00279 AST_CONTROL_RING = 2, /*!< Local ring */ 00280 AST_CONTROL_RINGING = 3, /*!< Remote end is ringing */ 00281 AST_CONTROL_ANSWER = 4, /*!< Remote end has answered */ 00282 AST_CONTROL_BUSY = 5, /*!< Remote end is busy */ 00283 AST_CONTROL_TAKEOFFHOOK = 6, /*!< Make it go off hook */ 00284 AST_CONTROL_OFFHOOK = 7, /*!< Line is off hook */ 00285 AST_CONTROL_CONGESTION = 8, /*!< Congestion (circuits busy) */ 00286 AST_CONTROL_FLASH = 9, /*!< Flash hook */ 00287 AST_CONTROL_WINK = 10, /*!< Wink */ 00288 AST_CONTROL_OPTION = 11, /*!< Set a low-level option */ 00289 AST_CONTROL_RADIO_KEY = 12, /*!< Key Radio */ 00290 AST_CONTROL_RADIO_UNKEY = 13, /*!< Un-Key Radio */ 00291 AST_CONTROL_PROGRESS = 14, /*!< Indicate PROGRESS */ 00292 AST_CONTROL_PROCEEDING = 15, /*!< Indicate CALL PROCEEDING */ 00293 AST_CONTROL_HOLD = 16, /*!< Indicate call is placed on hold */ 00294 AST_CONTROL_UNHOLD = 17, /*!< Indicate call is left from hold */ 00295 AST_CONTROL_VIDUPDATE = 18, /*!< Indicate video frame update */ 00296 AST_CONTROL_SRCUPDATE = 20, /*!< Indicate source of media has changed */ 00297 }; 00298 00299 #define AST_SMOOTHER_FLAG_G729 (1 << 0) 00300 #define AST_SMOOTHER_FLAG_BE (1 << 1) 00301 00302 /* Option identifiers and flags */ 00303 #define AST_OPTION_FLAG_REQUEST 0 00304 #define AST_OPTION_FLAG_ACCEPT 1 00305 #define AST_OPTION_FLAG_REJECT 2 00306 #define AST_OPTION_FLAG_QUERY 4 00307 #define AST_OPTION_FLAG_ANSWER 5 00308 #define AST_OPTION_FLAG_WTF 6 00309 00310 /*! Verify touchtones by muting audio transmission 00311 (and reception) and verify the tone is still present */ 00312 #define AST_OPTION_TONE_VERIFY 1 00313 00314 /*! Put a compatible channel into TDD (TTY for the hearing-impared) mode */ 00315 #define AST_OPTION_TDD 2 00316 00317 /*! Relax the parameters for DTMF reception (mainly for radio use) */ 00318 #define AST_OPTION_RELAXDTMF 3 00319 00320 /*! Set (or clear) Audio (Not-Clear) Mode */ 00321 #define AST_OPTION_AUDIO_MODE 4 00322 00323 /*! Set channel transmit gain 00324 * Option data is a single signed char 00325 representing number of decibels (dB) 00326 to set gain to (on top of any gain 00327 specified in channel driver) 00328 */ 00329 #define AST_OPTION_TXGAIN 5 00330 00331 /*! Set channel receive gain 00332 * Option data is a single signed char 00333 representing number of decibels (dB) 00334 to set gain to (on top of any gain 00335 specified in channel driver) 00336 */ 00337 #define AST_OPTION_RXGAIN 6 00338 00339 /* set channel into "Operator Services" mode */ 00340 #define AST_OPTION_OPRMODE 7 00341 00342 /*! Explicitly enable or disable echo cancelation for the given channel */ 00343 #define AST_OPTION_ECHOCAN 8 00344 00345 struct oprmode { 00346 struct ast_channel *peer; 00347 int mode; 00348 } ; 00349 00350 struct ast_option_header { 00351 /* Always keep in network byte order */ 00352 #if __BYTE_ORDER == __BIG_ENDIAN 00353 uint16_t flag:3; 00354 uint16_t option:13; 00355 #else 00356 #if __BYTE_ORDER == __LITTLE_ENDIAN 00357 uint16_t option:13; 00358 uint16_t flag:3; 00359 #else 00360 #error Byte order not defined 00361 #endif 00362 #endif 00363 uint8_t data[0]; 00364 }; 00365 00366 00367 /*! \brief Definition of supported media formats (codecs) */ 00368 struct ast_format_list { 00369 int visible; /*!< Can we see this entry */ 00370 int bits; /*!< bitmask value */ 00371 char *name; /*!< short name */ 00372 char *desc; /*!< Description */ 00373 int fr_len; /*!< Single frame length in bytes */ 00374 int min_ms; /*!< Min value */ 00375 int max_ms; /*!< Max value */ 00376 int inc_ms; /*!< Increment */ 00377 int def_ms; /*!< Default value */ 00378 unsigned int flags; /*!< Smoother flags */ 00379 int cur_ms; /*!< Current value */ 00380 }; 00381 00382 00383 /*! \brief Requests a frame to be allocated 00384 * 00385 * \param source 00386 * Request a frame be allocated. source is an optional source of the frame, 00387 * len is the requested length, or "0" if the caller will supply the buffer 00388 */ 00389 #if 0 /* Unimplemented */ 00390 struct ast_frame *ast_fralloc(char *source, int len); 00391 #endif 00392 00393 /*! 00394 * \brief Frees a frame 00395 * 00396 * \param fr Frame to free 00397 * \param cache Whether to consider this frame for frame caching 00398 */ 00399 void ast_frame_free(struct ast_frame *fr, int cache); 00400 00401 #define ast_frfree(fr) ast_frame_free(fr, 1) 00402 00403 /*! \brief Makes a frame independent of any static storage 00404 * \param fr frame to act upon 00405 * Take a frame, and if it's not been malloc'd, make a malloc'd copy 00406 * and if the data hasn't been malloced then make the 00407 * data malloc'd. If you need to store frames, say for queueing, then 00408 * you should call this function. 00409 * \return Returns a frame on success, NULL on error 00410 */ 00411 struct ast_frame *ast_frisolate(struct ast_frame *fr); 00412 00413 /*! \brief Copies a frame 00414 * \param fr frame to copy 00415 * Duplicates a frame -- should only rarely be used, typically frisolate is good enough 00416 * \return Returns a frame on success, NULL on error 00417 */ 00418 struct ast_frame *ast_frdup(const struct ast_frame *fr); 00419 00420 void ast_swapcopy_samples(void *dst, const void *src, int samples); 00421 00422 /* Helpers for byteswapping native samples to/from 00423 little-endian and big-endian. */ 00424 #if __BYTE_ORDER == __LITTLE_ENDIAN 00425 #define ast_frame_byteswap_le(fr) do { ; } while(0) 00426 #define ast_frame_byteswap_be(fr) do { struct ast_frame *__f = (fr); ast_swapcopy_samples(__f->data, __f->data, __f->samples); } while(0) 00427 #else 00428 #define ast_frame_byteswap_le(fr) do { struct ast_frame *__f = (fr); ast_swapcopy_samples(__f->data, __f->data, __f->samples); } while(0) 00429 #define ast_frame_byteswap_be(fr) do { ; } while(0) 00430 #endif 00431 00432 00433 /*! \brief Get the name of a format 00434 * \param format id of format 00435 * \return A static string containing the name of the format or "unknown" if unknown. 00436 */ 00437 char* ast_getformatname(int format); 00438 00439 /*! \brief Get the names of a set of formats 00440 * \param buf a buffer for the output string 00441 * \param size size of buf (bytes) 00442 * \param format the format (combined IDs of codecs) 00443 * Prints a list of readable codec names corresponding to "format". 00444 * ex: for format=AST_FORMAT_GSM|AST_FORMAT_SPEEX|AST_FORMAT_ILBC it will return "0x602 (GSM|SPEEX|ILBC)" 00445 * \return The return value is buf. 00446 */ 00447 char* ast_getformatname_multiple(char *buf, size_t size, int format); 00448 00449 /*! 00450 * \brief Gets a format from a name. 00451 * \param name string of format 00452 * \return This returns the form of the format in binary on success, 0 on error. 00453 */ 00454 int ast_getformatbyname(const char *name); 00455 00456 /*! \brief Get a name from a format 00457 * Gets a name from a format 00458 * \param codec codec number (1,2,4,8,16,etc.) 00459 * \return This returns a static string identifying the format on success, 0 on error. 00460 */ 00461 char *ast_codec2str(int codec); 00462 00463 /*! \page ast_smooth 00464 The ast_smoother interface was designed specifically 00465 to take frames of variant sizes and produce frames of a single expected 00466 size, precisely what you want to do. 00467 00468 The basic interface is: 00469 00470 - Initialize with ast_smoother_new() 00471 - Queue input frames with ast_smoother_feed() 00472 - Get output frames with ast_smoother_read() 00473 - when you're done, free the structure with ast_smoother_free() 00474 - Also see ast_smoother_test_flag(), ast_smoother_set_flags(), ast_smoother_get_flags(), ast_smoother_reset() 00475 */ 00476 struct ast_smoother; 00477 00478 struct ast_format_list *ast_get_format_list_index(int index); 00479 struct ast_format_list *ast_get_format_list(size_t *size); 00480 struct ast_smoother *ast_smoother_new(int bytes); 00481 void ast_smoother_set_flags(struct ast_smoother *smoother, int flags); 00482 int ast_smoother_get_flags(struct ast_smoother *smoother); 00483 int ast_smoother_test_flag(struct ast_smoother *s, int flag); 00484 void ast_smoother_free(struct ast_smoother *s); 00485 void ast_smoother_reset(struct ast_smoother *s, int bytes); 00486 int __ast_smoother_feed(struct ast_smoother *s, struct ast_frame *f, int swap); 00487 struct ast_frame *ast_smoother_read(struct ast_smoother *s); 00488 #define ast_smoother_feed(s,f) __ast_smoother_feed(s, f, 0) 00489 #if __BYTE_ORDER == __LITTLE_ENDIAN 00490 #define ast_smoother_feed_be(s,f) __ast_smoother_feed(s, f, 1) 00491 #define ast_smoother_feed_le(s,f) __ast_smoother_feed(s, f, 0) 00492 #else 00493 #define ast_smoother_feed_be(s,f) __ast_smoother_feed(s, f, 0) 00494 #define ast_smoother_feed_le(s,f) __ast_smoother_feed(s, f, 1) 00495 #endif 00496 00497 void ast_frame_dump(const char *name, struct ast_frame *f, char *prefix); 00498 00499 /*! \page AudioCodecPref Audio Codec Preferences 00500 In order to negotiate audio codecs in the order they are configured 00501 in <channel>.conf for a device, we set up codec preference lists 00502 in addition to the codec capabilities setting. The capabilities 00503 setting is a bitmask of audio and video codecs with no internal 00504 order. This will reflect the offer given to the other side, where 00505 the prefered codecs will be added to the top of the list in the 00506 order indicated by the "allow" lines in the device configuration. 00507 00508 Video codecs are not included in the preference lists since they 00509 can't be transcoded and we just have to pick whatever is supported 00510 */ 00511 00512 /*! \brief Initialize an audio codec preference to "no preference" See \ref AudioCodecPref */ 00513 void ast_codec_pref_init(struct ast_codec_pref *pref); 00514 00515 /*! \brief Codec located at a particular place in the preference index See \ref AudioCodecPref */ 00516 int ast_codec_pref_index(struct ast_codec_pref *pref, int index); 00517 00518 /*! \brief Remove audio a codec from a preference list */ 00519 void ast_codec_pref_remove(struct ast_codec_pref *pref, int format); 00520 00521 /*! \brief Append a audio codec to a preference list, removing it first if it was already there 00522 */ 00523 int ast_codec_pref_append(struct ast_codec_pref *pref, int format); 00524 00525 /*! \brief Prepend an audio codec to a preference list, removing it first if it was already there 00526 */ 00527 void ast_codec_pref_prepend(struct ast_codec_pref *pref, int format, int only_if_existing); 00528 00529 /*! \brief Select the best audio format according to preference list from supplied options. 00530 If "find_best" is non-zero then if nothing is found, the "Best" format of 00531 the format list is selected, otherwise 0 is returned. */ 00532 int ast_codec_choose(struct ast_codec_pref *pref, int formats, int find_best); 00533 00534 /*! \brief Set packet size for codec 00535 */ 00536 int ast_codec_pref_setsize(struct ast_codec_pref *pref, int format, int framems); 00537 00538 /*! \brief Get packet size for codec 00539 */ 00540 struct ast_format_list ast_codec_pref_getsize(struct ast_codec_pref *pref, int format); 00541 00542 /*! \brief Parse an "allow" or "deny" line in a channel or device configuration 00543 and update the capabilities mask and pref if provided. 00544 Video codecs are not added to codec preference lists, since we can not transcode 00545 */ 00546 void ast_parse_allow_disallow(struct ast_codec_pref *pref, int *mask, const char *list, int allowing); 00547 00548 /*! \brief Dump audio codec preference list into a string */ 00549 int ast_codec_pref_string(struct ast_codec_pref *pref, char *buf, size_t size); 00550 00551 /*! \brief Shift an audio codec preference list up or down 65 bytes so that it becomes an ASCII string */ 00552 void ast_codec_pref_convert(struct ast_codec_pref *pref, char *buf, size_t size, int right); 00553 00554 /*! \brief Returns the number of samples contained in the frame */ 00555 int ast_codec_get_samples(struct ast_frame *f); 00556 00557 /*! \brief Returns the number of bytes for the number of samples of the given format */ 00558 int ast_codec_get_len(int format, int samples); 00559 00560 /*! \brief Appends a frame to the end of a list of frames, truncating the maximum length of the list */ 00561 struct ast_frame *ast_frame_enqueue(struct ast_frame *head, struct ast_frame *f, int maxlen, int dupe); 00562 00563 00564 /*! \brief Gets duration in ms of interpolation frame for a format */ 00565 static inline int ast_codec_interp_len(int format) 00566 { 00567 return (format == AST_FORMAT_ILBC) ? 30 : 20; 00568 } 00569 00570 /*! 00571 \brief Adjusts the volume of the audio samples contained in a frame. 00572 \param f The frame containing the samples (must be AST_FRAME_VOICE and AST_FORMAT_SLINEAR) 00573 \param adjustment The number of dB to adjust up or down. 00574 \return 0 for success, non-zero for an error 00575 */ 00576 int ast_frame_adjust_volume(struct ast_frame *f, int adjustment); 00577 00578 /*! 00579 \brief Sums two frames of audio samples. 00580 \param f1 The first frame (which will contain the result) 00581 \param f2 The second frame 00582 \return 0 for success, non-zero for an error 00583 00584 The frames must be AST_FRAME_VOICE and must contain AST_FORMAT_SLINEAR samples, 00585 and must contain the same number of samples. 00586 */ 00587 int ast_frame_slinear_sum(struct ast_frame *f1, struct ast_frame *f2); 00588 00589 /*! 00590 * \brief Get the sample rate for a given format. 00591 */ 00592 static force_inline int ast_format_rate(int format) 00593 { 00594 if (format == AST_FORMAT_G722) 00595 return 16000; 00596 00597 return 8000; 00598 } 00599 00600 #if defined(__cplusplus) || defined(c_plusplus) 00601 } 00602 #endif 00603 00604 #endif /* _ASTERISK_FRAME_H */