t30.h

Go to the documentation of this file.
00001 /*
00002  * SpanDSP - a series of DSP components for telephony
00003  *
00004  * t30.h - definitions for T.30 fax processing
00005  *
00006  * Written by Steve Underwood <steveu@coppice.org>
00007  *
00008  * Copyright (C) 2003 Steve Underwood
00009  *
00010  * All rights reserved.
00011  *
00012  * This program is free software; you can redistribute it and/or modify
00013  * it under the terms of the GNU General Public License version 2, as
00014  * published by the Free Software Foundation.
00015  *
00016  * This program is distributed in the hope that it will be useful,
00017  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00018  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00019  * GNU General Public License for more details.
00020  *
00021  * You should have received a copy of the GNU General Public License
00022  * along with this program; if not, write to the Free Software
00023  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
00024  *
00025  * $Id: t30.h,v 1.93 2008/02/20 13:01:45 steveu Exp $
00026  */
00027 
00028 /*! \file */
00029 
00030 #if !defined(_SPANDSP_T30_H_)
00031 #define _SPANDSP_T30_H_
00032 
00033 /*! \page t30_page T.30 FAX protocol handling
00034 
00035 \section t30_page_sec_1 What does it do?
00036 The T.30 protocol is the core protocol used for FAX transmission. This module
00037 implements most of its key featrues. It does not interface to the outside work.
00038 Seperate modules do that for T.38, analogue line, and other forms of FAX
00039 communication.
00040 
00041 Current features of this module include:
00042 
00043     - FAXing to and from multi-page TIFF/F files, whose images are one of the standard
00044       FAX sizes.
00045     - T.4 1D (MH), T.4 2D,(MR) and T.6 (MMR) compression.
00046     - Error correction (ECM)
00047     - All standard resolutions and page sizes
00048 
00049 \section t30_page_sec_2 How does it work?
00050 
00051 Some of the following is paraphrased from some notes found a while ago on the Internet.
00052 I cannot remember exactly where they came from, but they are useful.
00053 
00054 The answer (CED) tone
00055 
00056 The T.30 standard says an answering fax device must send CED (a 2100Hz tone) for
00057 approximately 3 seconds before sending the first handshake message. Some machines
00058 send an 1100Hz or 1850Hz tone, and some send no tone at all. In fact, this answer
00059 tone is so unpredictable, it cannot really be used. It should, however, always be
00060 generated according to the specification.
00061 
00062 Common Timing Deviations
00063 
00064 The T.30 spec. specifies a number of time-outs. For example, after dialing a number,
00065 a calling fax system should listen for a response for 35 seconds before giving up.
00066 These time-out periods are as follows: 
00067 
00068     * T1 - 35+-5s: the maximum time for which two fax system will attempt to identify each other
00069     * T2 - 6+-1s:  a time-out used to start the sequence for changing transmit parameters
00070     * T3 - 10+-5s: a time-out used in handling operator interrupts
00071     * T5 - 60+-5s: a time-out used in error correction mode
00072 
00073 These time-outs are sometimes misinterpreted. In addition, they are routinely
00074 ignored, sometimes with good reason. For example, after placing a call, the
00075 calling fax system is supposed to wait for 35 seconds before giving up. If the
00076 answering unit does not answer on the first ring or if a voice answering machine
00077 is connected to the line, or if there are many delays through the network,
00078 the delay before answer can be much longer than 35 seconds. 
00079 
00080 Fax units that support error correction mode (ECM) can respond to a post-image
00081 handshake message with a receiver not ready (RNR) message. The calling unit then
00082 queries the receiving fax unit with a receiver ready (RR) message. If the
00083 answering unit is still busy (printing for example), it will repeat the RNR
00084 message. According to the T.30 standard, this sequence (RR/RNR RR/RNR) can be
00085 repeated for up to the end of T5 (60+-5s). However, many fax systems
00086 ignore the time-out and will continue the sequence indefinitely, unless the user
00087 manually overrides. 
00088 
00089 All the time-outs are subject to alteration, and sometimes misuse. Good T.30
00090 implementations must do the right thing, and tolerate others doing the wrong thing.
00091  
00092 Variations in the inter-carrier gap
00093 
00094 T.30 specifies 75+-20ms of silence between signals using different modulation
00095 schemes. Examples are between the end of a DCS signal and the start of a TCF signal,
00096 and between the end of an image and the start of a post-image signal. Many fax systems
00097 violate this requirement, especially for the silent period between DCS and TCF.
00098 This may be stretched to well over 100ms. If this period is too long, it can interfere with
00099 handshake signal error recovery, should a packet be corrupted on the line. Systems
00100 should ensure they stay within the prescribed T.30 limits, and be tolerant of others
00101 being out of spec.. 
00102 
00103 Other timing variations
00104 
00105 Testing is required to determine the ability of a fax system to handle
00106 variations in the duration of pauses between unacknowledged handshake message
00107 repetitions, and also in the pauses between the receipt of a handshake command and
00108 the start of a response to that command. In order to reduce the total
00109 transmission time, many fax systems start sending a response message before the
00110 end of the command has been received. 
00111 
00112 Other deviations from the T.30 standard
00113 
00114 There are many other commonly encountered variations between machines, including:
00115 
00116     * frame sequence deviations
00117     * preamble and flag sequence variations
00118     * improper EOM usage
00119     * unusual data rate fallback sequences
00120     * common training pattern detection algorithms
00121     * image transmission deviations
00122     * use of the talker echo protect tone
00123     * image padding and short lines
00124     * RTP/RTN handshake message usage
00125     * long duration lines
00126     * nonstandard disconnect sequences
00127     * DCN usage
00128 */
00129 
00130 #define T30_MAX_DIS_DTC_DCS_LEN     22
00131 #define T30_MAX_IDENT_LEN           20
00132 #define T30_MAX_LOCAL_NSF_LEN       100
00133 #define T30_MAX_PAGE_HEADER_INFO    50
00134 
00135 typedef struct t30_state_s t30_state_t;
00136 
00137 /*!
00138     T.30 phase B callback handler.
00139     \brief T.30 phase B callback handler.
00140     \param s The T.30 context.
00141     \param user_data An opaque pointer.
00142     \param result The phase B event code.
00143 */
00144 typedef void (t30_phase_b_handler_t)(t30_state_t *s, void *user_data, int result);
00145 
00146 /*!
00147     T.30 phase D callback handler.
00148     \brief T.30 phase D callback handler.
00149     \param s The T.30 context.
00150     \param user_data An opaque pointer.
00151     \param result The phase D event code.
00152 */
00153 typedef void (t30_phase_d_handler_t)(t30_state_t *s, void *user_data, int result);
00154 
00155 /*!
00156     T.30 phase E callback handler.
00157     \brief T.30 phase E callback handler.
00158     \param s The T.30 context.
00159     \param user_data An opaque pointer.
00160     \param completion_code The phase E completion code.
00161 */
00162 typedef void (t30_phase_e_handler_t)(t30_state_t *s, void *user_data, int completion_code);
00163 
00164 /*!
00165     T.30 document handler.
00166     \brief T.30 document handler.
00167     \param s The T.30 context.
00168     \param user_data An opaque pointer.
00169     \param result The document event code.
00170 */
00171 typedef int (t30_document_handler_t)(t30_state_t *s, void *user_data, int status);
00172 
00173 /*!
00174     T.30 set a receive or transmit type handler.
00175     \brief T.30 set a receive or transmit type handler.
00176     \param user_data An opaque pointer.
00177     \param type The modem, tone or silence to be sent or received.
00178     \param short_train TRUE if the short training sequence should be used (where one exists).
00179     \param use_hdlc FALSE for bit stream, TRUE for HDLC framing.
00180 */
00181 typedef void (t30_set_handler_t)(void *user_data, int type, int short_train, int use_hdlc);
00182 
00183 /*!
00184     T.30 send HDLC handler.
00185     \brief T.30 send HDLC handler.
00186     \param user_data An opaque pointer.
00187     \param msg The HDLC message.
00188     \param len The length of the message.
00189 */
00190 typedef void (t30_send_hdlc_handler_t)(void *user_data, const uint8_t *msg, int len);
00191 
00192 /*!
00193     T.30 protocol completion codes, at phase E.
00194 */
00195 enum
00196 {
00197     T30_ERR_OK = 0,         /*! OK */
00198 
00199     /* Link problems */
00200     T30_ERR_CEDTONE,        /*! The CED tone exceeded 5s */
00201     T30_ERR_T0_EXPIRED,     /*! Timed out waiting for initial communication */
00202     T30_ERR_T1_EXPIRED,     /*! Timed out waiting for the first message */
00203     T30_ERR_T3_EXPIRED,     /*! Timed out waiting for procedural interrupt */
00204     T30_ERR_HDLC_CARRIER,   /*! The HDLC carrier did not stop in a timely manner */
00205     T30_ERR_CANNOT_TRAIN,   /*! Failed to train with any of the compatible modems */
00206     T30_ERR_OPERINTFAIL,    /*! Operator intervention failed */
00207     T30_ERR_INCOMPATIBLE,   /*! Far end is not compatible */
00208     T30_ERR_RX_INCAPABLE,   /*! Far end is not able to receive */
00209     T30_ERR_TX_INCAPABLE,   /*! Far end is not able to transmit */
00210     T30_ERR_NORESSUPPORT,   /*! Far end cannot receive at the resolution of the image */
00211     T30_ERR_NOSIZESUPPORT,  /*! Far end cannot receive at the size of image */
00212     T30_ERR_UNEXPECTED,     /*! Unexpected message received */
00213 
00214     /* TIFF file problems */
00215     T30_ERR_FILEERROR,      /*! TIFF/F file cannot be opened */
00216     T30_ERR_NOPAGE,         /*! TIFF/F page not found */
00217     T30_ERR_BADTIFF,        /*! TIFF/F format is not compatible */
00218 
00219     /* Phase E status values returned to a transmitter */
00220     T30_ERR_BADDCSTX,       /*! Received bad response to DCS or training */
00221     T30_ERR_BADPGTX,        /*! Received a DCN from remote after sending a page */
00222     T30_ERR_ECMPHDTX,       /*! Invalid ECM response received from receiver */
00223     T30_ERR_T5_EXPIRED,     /*! Timed out waiting for receiver ready (ECM mode) */
00224     T30_ERR_GOTDCNTX,       /*! Received a DCN while waiting for a DIS */
00225     T30_ERR_INVALRSPTX,     /*! Invalid response after sending a page */
00226     T30_ERR_NODISTX,        /*! Received other than DIS while waiting for DIS */
00227     T30_ERR_PHBDEADTX,      /*! Received no response to DCS, training or TCF */
00228     T30_ERR_PHDDEADTX,      /*! No response after sending a page */
00229 
00230     /* Phase E status values returned to a receiver */
00231     T30_ERR_ECMPHDRX,       /*! Invalid ECM response received from transmitter */
00232     T30_ERR_GOTDCSRX,       /*! DCS received while waiting for DTC */
00233     T30_ERR_INVALCMDRX,     /*! Unexpected command after page received */
00234     T30_ERR_NOCARRIERRX,    /*! Carrier lost during fax receive */
00235     T30_ERR_NOEOLRX,        /*! Timed out while waiting for EOL (end Of line) */
00236     T30_ERR_NOFAXRX,        /*! Timed out while waiting for first line */
00237     T30_ERR_T2EXPDCNRX,     /*! Timer T2 expired while waiting for DCN */
00238     T30_ERR_T2EXPDRX,       /*! Timer T2 expired while waiting for phase D */
00239     T30_ERR_T2EXPFAXRX,     /*! Timer T2 expired while waiting for fax page */
00240     T30_ERR_T2EXPMPSRX,     /*! Timer T2 expired while waiting for next fax page */
00241     T30_ERR_T2EXPRRRX,      /*! Timer T2 expired while waiting for RR command */
00242     T30_ERR_T2EXPRX,        /*! Timer T2 expired while waiting for NSS, DCS or MCF */
00243     T30_ERR_DCNWHYRX,       /*! Unexpected DCN while waiting for DCS or DIS */
00244     T30_ERR_DCNDATARX,      /*! Unexpected DCN while waiting for image data */
00245     T30_ERR_DCNFAXRX,       /*! Unexpected DCN while waiting for EOM, EOP or MPS */
00246     T30_ERR_DCNPHDRX,       /*! Unexpected DCN after EOM or MPS sequence */
00247     T30_ERR_DCNRRDRX,       /*! Unexpected DCN after RR/RNR sequence */
00248     T30_ERR_DCNNORTNRX,     /*! Unexpected DCN after requested retransmission */
00249 
00250     T30_ERR_BADPAGE,        /*! TIFF/F page number tag missing */
00251     T30_ERR_BADTAG,         /*! Incorrect values for TIFF/F tags */
00252     T30_ERR_BADTIFFHDR,     /*! Bad TIFF/F header - incorrect values in fields */
00253     T30_ERR_NODATA,         /*! Data requested is not available (NSF, DIS, DCS) */
00254     T30_ERR_NOMEM,          /*! Cannot allocate memory for more pages */
00255     T30_ERR_NOPOLL,         /*! Poll not accepted */
00256     T30_ERR_RETRYDCN,       /*! Disconnected after permitted retries */
00257     T30_ERR_CALLDROPPED     /*! The call dropped prematurely */
00258 };
00259 
00260 /*!
00261     I/O modes for the T.30 protocol.
00262 */
00263 enum
00264 {
00265     T30_MODEM_NONE = 0,
00266     T30_MODEM_PAUSE,
00267     T30_MODEM_CED,
00268     T30_MODEM_CNG,
00269     T30_MODEM_V21,
00270     T30_MODEM_V27TER_2400,
00271     T30_MODEM_V27TER_4800,
00272     T30_MODEM_V29_7200,
00273     T30_MODEM_V29_9600,
00274     T30_MODEM_V17_7200,
00275     T30_MODEM_V17_9600,
00276     T30_MODEM_V17_12000,
00277     T30_MODEM_V17_14400,
00278     T30_MODEM_DONE
00279 };
00280 
00281 enum
00282 {
00283     T30_FRONT_END_SEND_STEP_COMPLETE = 0,
00284     /*! The current receive has completed. This is only needed to report an
00285         unexpected end of the receive operation, as might happen with T.38
00286         dying. */
00287     T30_FRONT_END_RECEIVE_COMPLETE,
00288     T30_FRONT_END_SIGNAL_PRESENT,
00289     T30_FRONT_END_SIGNAL_ABSENT
00290 };
00291 
00292 enum
00293 {
00294     T30_SUPPORT_V27TER = 0x01,
00295     T30_SUPPORT_V29 = 0x02,
00296     T30_SUPPORT_V17 = 0x04,
00297     T30_SUPPORT_V34 = 0x08,
00298     T30_SUPPORT_IAF = 0x10,
00299 };
00300 
00301 enum
00302 {
00303     T30_SUPPORT_NO_COMPRESSION = 0x01,
00304     T30_SUPPORT_T4_1D_COMPRESSION = 0x02,
00305     T30_SUPPORT_T4_2D_COMPRESSION = 0x04,
00306     T30_SUPPORT_T6_COMPRESSION = 0x08,
00307     T30_SUPPORT_T85_COMPRESSION = 0x10,     /* Monochrome JBIG */
00308     T30_SUPPORT_T43_COMPRESSION = 0x20,     /* Colour JBIG */
00309     T30_SUPPORT_T45_COMPRESSION = 0x40      /* Run length colour compression */
00310 };
00311 
00312 enum
00313 {
00314     T30_SUPPORT_STANDARD_RESOLUTION = 0x01,
00315     T30_SUPPORT_FINE_RESOLUTION = 0x02,
00316     T30_SUPPORT_SUPERFINE_RESOLUTION = 0x04,
00317 
00318     T30_SUPPORT_R4_RESOLUTION = 0x10000,
00319     T30_SUPPORT_R8_RESOLUTION = 0x20000,
00320     T30_SUPPORT_R16_RESOLUTION = 0x40000,
00321 
00322     T30_SUPPORT_300_300_RESOLUTION = 0x100000,
00323     T30_SUPPORT_400_400_RESOLUTION = 0x200000,
00324     T30_SUPPORT_600_600_RESOLUTION = 0x400000,
00325     T30_SUPPORT_1200_1200_RESOLUTION = 0x800000,
00326     T30_SUPPORT_300_600_RESOLUTION = 0x1000000,
00327     T30_SUPPORT_400_800_RESOLUTION = 0x2000000,
00328     T30_SUPPORT_600_1200_RESOLUTION = 0x4000000
00329 };
00330 
00331 enum
00332 {
00333     T30_SUPPORT_215MM_WIDTH = 0x01,
00334     T30_SUPPORT_255MM_WIDTH = 0x02,
00335     T30_SUPPORT_303MM_WIDTH = 0x04,
00336 
00337     T30_SUPPORT_UNLIMITED_LENGTH = 0x10000,
00338     T30_SUPPORT_A4_LENGTH = 0x20000,
00339     T30_SUPPORT_B4_LENGTH = 0x40000,
00340     T30_SUPPORT_US_LETTER_LENGTH = 0x80000,
00341     T30_SUPPORT_US_LEGAL_LENGTH = 0x100000
00342 };
00343 
00344 enum
00345 {
00346     T30_SUPPORT_SEP = 0x01,
00347     T30_SUPPORT_PSA = 0x02
00348 };
00349 
00350 enum
00351 {
00352     T30_IAF_MODE_T37 = 0x01,
00353     T30_IAF_MODE_T38 = 0x02,
00354     T30_IAF_MODE_FLOW_CONTROL = 0x04,
00355     /*! Continuous flow mode means data is sent as fast as possible, usually across
00356         the Internet, where speed is not constrained by a PSTN modem. */
00357     T30_IAF_MODE_CONTINUOUS_FLOW = 0x08,
00358     /*! No TCF means TCF is not exchanged. The end points must sort out usable speed
00359         issues locally. */
00360     T30_IAF_MODE_NO_TCF = 0x10,
00361     /*! No fill bits means do not insert fill bits, even if the T.30 messages request
00362         them. */
00363     T30_IAF_MODE_NO_FILL_BITS = 0x20,
00364     /*! No indicators means do not send indicator messages when using T.38. */
00365     T30_IAF_MODE_NO_INDICATORS = 0x40
00366 };
00367 
00368 /*!
00369     T.30 FAX channel descriptor. This defines the state of a single working
00370     instance of a T.30 FAX channel.
00371 */
00372 struct t30_state_s
00373 {
00374     /* This must be kept the first thing in the structure, so it can be pointed
00375        to reliably as the structures change over time. */
00376     /*! \brief T.4 context for reading or writing image data. */
00377     t4_state_t t4;
00378 
00379     /*! \brief TRUE if behaving as the calling party */
00380     int calling_party;
00381     
00382     /*! \brief The received DCS, formatted as an ASCII string, for inclusion
00383                in the TIFF file. */
00384     char rx_dcs_string[T30_MAX_DIS_DTC_DCS_LEN*3 + 1];
00385     /*! \brief The local identifier string. */
00386     char local_ident[T30_MAX_IDENT_LEN + 1];
00387     /*! \brief The identifier string supplied by the remote FAX machine. */
00388     char far_ident[T30_MAX_IDENT_LEN + 1];
00389     /*! \brief The sub-address string to be sent to the remote FAX machine. */
00390     char local_sub_address[T30_MAX_IDENT_LEN + 1];
00391     /*! \brief The sub-address string supplied by the remote FAX machine. */
00392     char far_sub_address[T30_MAX_IDENT_LEN + 1];
00393     /*! \brief The selective polling sub-address supplied by the remote FAX machine. */
00394     char sep_address[T30_MAX_IDENT_LEN + 1];
00395     /*! \brief The polled sub-address supplied by the remote FAX machine. */
00396     char psa_address[T30_MAX_IDENT_LEN + 1];
00397     /*! \brief A password to be associated with the T.30 context. */
00398     char local_password[T30_MAX_IDENT_LEN + 1];
00399     /*! \brief A password expected from the far end. */
00400     char far_password[T30_MAX_IDENT_LEN + 1];
00401     /*! \brief The text which will be used in FAX page header. No text results
00402                in no header line. */
00403     char header_info[T30_MAX_PAGE_HEADER_INFO + 1];
00404     /*! \brief The country of origin of the remote machine, if known, else NULL. */
00405     const char *country;
00406     /*! \brief The vendor of the remote machine, if known, else NULL. */
00407     const char *vendor;
00408     /*! \brief The model of the remote machine, if known, else NULL. */
00409     const char *model;
00410     /*! \brief An NSF frame to be sent to the far end. */
00411     uint8_t local_nsf[T30_MAX_LOCAL_NSF_LEN];
00412     /*! \brief The length of the NSF frame to be sent to the far end. */
00413     int local_nsf_len;
00414 
00415     /*! \brief A pointer to a callback routine to be called when phase B events
00416         occur. */
00417     t30_phase_b_handler_t *phase_b_handler;
00418     /*! \brief An opaque pointer supplied in event B callbacks. */
00419     void *phase_b_user_data;
00420     /*! \brief A pointer to a callback routine to be called when phase D events
00421         occur. */
00422     t30_phase_d_handler_t *phase_d_handler;
00423     /*! \brief An opaque pointer supplied in event D callbacks. */
00424     void *phase_d_user_data;
00425     /*! \brief A pointer to a callback routine to be called when phase E events
00426         occur. */
00427     t30_phase_e_handler_t *phase_e_handler;
00428     /*! \brief An opaque pointer supplied in event E callbacks. */
00429     void *phase_e_user_data;
00430 
00431     /*! \brief A pointer to a callback routine to be called when document events
00432         (e.g. end of transmitted document) occur. */
00433     t30_document_handler_t *document_handler;
00434     /*! \brief An opaque pointer supplied in document callbacks. */
00435     void *document_user_data;
00436 
00437     /*! \brief The handler for changes to the receive mode */
00438     t30_set_handler_t *set_rx_type_handler;
00439     /*! \brief An opaque pointer passed to the handler for changes to the receive mode */
00440     void *set_rx_type_user_data;
00441     /*! \brief The handler for changes to the transmit mode */
00442     t30_set_handler_t *set_tx_type_handler;
00443     /*! \brief An opaque pointer passed to the handler for changes to the transmit mode */
00444     void *set_tx_type_user_data;
00445 
00446     /*! \brief The transmitted HDLC frame handler. */
00447     t30_send_hdlc_handler_t *send_hdlc_handler;
00448     /*! \brief An opaque pointer passed to the transmitted HDLC frame handler. */
00449     void *send_hdlc_user_data;
00450 
00451     /*! \brief The DIS code for the minimum scan row time we require. This is usually 0ms,
00452         but if we are trying to simulate another type of FAX machine, we may need a non-zero
00453         value here. */
00454     uint8_t local_min_scan_time_code;
00455 
00456     /*! \brief The current T.30 phase. */
00457     int phase;
00458     /*! \brief The T.30 phase to change to when the current phase ends. */
00459     int next_phase;
00460     /*! \brief The current state of the T.30 state machine. */
00461     int state;
00462     /*! \brief The step in sending a sequence of HDLC frames. */
00463     int step;
00464 
00465     /*! \brief The preparation buffer for the DCS message to be transmitted. */
00466     uint8_t dcs_frame[T30_MAX_DIS_DTC_DCS_LEN];
00467     /*! \brief The length of the DCS message to be transmitted. */
00468     int dcs_len;
00469     /*! \brief The preparation buffer for DIS or DTC message to be transmitted. */
00470     uint8_t local_dis_dtc_frame[T30_MAX_DIS_DTC_DCS_LEN];
00471     /*! \brief The length of the DIS or DTC message to be transmitted. */
00472     int local_dis_dtc_len;
00473     /*! \brief The last DIS or DTC message received form the far end. */
00474     uint8_t far_dis_dtc_frame[T30_MAX_DIS_DTC_DCS_LEN];
00475     /*! \brief The length of the last DIS or DTC message received form the far end. */
00476     int far_dis_dtc_len;
00477     /*! \brief TRUE if a valid DIS has been received from the far end. */
00478     int dis_received;
00479 
00480     /*! \brief A flag to indicate a message is in progress. */
00481     int in_message;
00482 
00483     /*! \brief TRUE if the short training sequence should be used. */
00484     int short_train;
00485 
00486     /*! \brief A count of the number of bits in the trainability test. */
00487     int training_test_bits;
00488     /*! \brief The current count of consecutive zero bits, during the trainability test. */
00489     int training_current_zeros;
00490     /*! \brief The maximum consecutive zero bits seen to date, during the trainability test. */
00491     int training_most_zeros;
00492 
00493     /*! \brief The current fallback step for the fast message transfer modem. */
00494     int current_fallback;
00495     /*! \brief The subset of supported modems allowed at the current time, allowing for negotiation. */
00496     int current_permitted_modems;
00497     /*! \brief TRUE if a carrier is present. Otherwise FALSE. */
00498     int rx_signal_present;
00499     /*! \brief TRUE if a modem has trained correctly. */
00500     int rx_trained;
00501     int current_rx_type;
00502     int current_tx_type;
00503 
00504     /*! \brief T0 is the answer timeout when calling another FAX machine.
00505         Placing calls is handled outside the FAX processing, but this timeout keeps
00506         running until V.21 modulation is sent or received.
00507         T1 is the remote terminal identification timeout (in audio samples). */
00508     int timer_t0_t1;
00509     /*! \brief T2 is the HDLC command timeout.
00510                T4 is the HDLC response timeout (in audio samples). */
00511     int timer_t2_t4;
00512     /*! \brief TRUE if the T2/T4 timer is actually timing T4 */
00513     int timer_is_t4;
00514     /*! \brief Procedural interrupt timeout (in audio samples). */
00515     int timer_t3;
00516     /*! \brief This is only used in error correcting mode. */
00517     int timer_t5;
00518     /*! \brief This is only used in full duplex (e.g. ISDN) modes. */
00519     int timer_t6;
00520     /*! \brief This is only used in full duplex (e.g. ISDN) modes. */
00521     int timer_t7;
00522     /*! \brief This is only used in full duplex (e.g. ISDN) modes. */
00523     int timer_t8;
00524 
00525     /*! \brief TRUE once the far end FAX entity has been detected. */
00526     int far_end_detected;
00527 
00528     /*! \brief TRUE if a local T.30 interrupt is pending. */
00529     int local_interrupt_pending;
00530     /*! \brief The image coding being used on the line. */
00531     int line_encoding;
00532     /*! \brief The image coding being used for output files. */
00533     int output_encoding;
00534     /*! \brief The current DCS message minimum scan time code. */
00535     uint8_t min_scan_time_code;
00536     /*! \brief The X direction resolution of the current image, in pixels per metre. */
00537     int x_resolution;
00538     /*! \brief The Y direction resolution of the current image, in pixels per metre. */
00539     int y_resolution;
00540     /*! \brief The width of the current image, in pixels. */
00541     t4_image_width_t image_width;
00542     /*! \brief Current number of retries of the action in progress. */
00543     int retries;
00544     /*! \brief TRUE if error correcting mode is used. */
00545     int error_correcting_mode;
00546     /*! \brief The current count of consecutive T30_PPR messages. */
00547     int ppr_count;
00548     /*! \brief The current count of consecutive T30_RNR messages. */
00549     int receiver_not_ready_count;
00550     /*! \brief The number of octets to be used per ECM frame. */
00551     int octets_per_ecm_frame;
00552     /*! \brief The ECM partial page buffer. */
00553     uint8_t ecm_data[256][260];
00554     /*! \brief The lengths of the frames in the ECM partial page buffer. */
00555     int16_t ecm_len[256];
00556     /*! \brief A bit map of the OK ECM frames, constructed as a PPR frame. */
00557     uint8_t ecm_frame_map[3 + 32];
00558     
00559     /*! \brief The current page number, in ECM mode */
00560     int ecm_page;
00561     /*! \brief The current block number, in ECM mode */
00562     int ecm_block;
00563     /*! \brief The number of frames in the current block number, in ECM mode */
00564     int ecm_frames;
00565     /*! \brief The number of frames sent in the current burst of image transmission, in ECM mode */
00566     int ecm_frames_this_tx_burst;
00567     /*! \brief The current ECM frame, during ECM transmission. */
00568     int ecm_current_tx_frame;
00569     /*! \brief TRUE if we are at the end of an ECM page to se sent - i.e. there are no more
00570         partial pages still to come. */
00571     int ecm_at_page_end;
00572     int next_tx_step;
00573     int next_rx_step;
00574     /*! \brief Image file name for image reception. */
00575     char rx_file[256];
00576     /*! \brief The last page we are prepared accept for a received image file. -1 means no restriction. */
00577     int rx_stop_page;
00578     /*! \brief Image file name to be sent. */
00579     char tx_file[256];
00580     /*! \brief The first page to be sent from the image file. -1 means no restriction. */
00581     int tx_start_page;
00582     /*! \brief The last page to be sent from the image file. -1 means no restriction. */
00583     int tx_stop_page;
00584     int current_status;
00585     /*! \brief Internet Aware FAX mode bit mask. */
00586     int iaf;
00587     /*! \brief A bit mask of the currently supported modem types. */
00588     int supported_modems;
00589     /*! \brief A bit mask of the currently supported image compression modes. */
00590     int supported_compressions;
00591     /*! \brief A bit mask of the currently supported image resolutions. */
00592     int supported_resolutions;
00593     /*! \brief A bit mask of the currently supported image sizes. */
00594     int supported_image_sizes;
00595     /*! \brief A bit mask of the currently supported polling features. */
00596     int supported_polling_features;
00597     /*! \brief TRUE is T30_FNV message handling is enabled. */
00598     int support_fnv;
00599     /*! \brief TRUE is T30_CRP message handling is enabled. */
00600     int crp_enabled;
00601     /*! \brief TRUE is ECM mode handling is enabled. */
00602     int ecm_allowed;
00603     
00604     /*! \brief the FCF2 field of the last PPS message we received. */
00605     int last_pps_fcf2;
00606     /*! \brief The number of the first ECM frame which we do not currently received correctly. For
00607         a partial page received correctly, this will be one greater than the number of frames it
00608         contains. */
00609     int ecm_first_bad_frame;
00610     /*! \brief A count of successfully received ECM frames, to assess progress as a basis for
00611         deciding whether to continue error correction when PPRs keep repeating. */
00612     int ecm_progress;
00613 
00614     /*! \brief A password received from the far end. */
00615     char received_password[T30_MAX_IDENT_LEN + 1];
00616     /*! \brief TRUE if the far end requires that we send a password. */
00617     int password_required;
00618 
00619     /*! \brief Error and flow logging control */
00620     logging_state_t logging;
00621 };
00622 
00623 typedef struct
00624 {
00625     /*! \brief The current bit rate for image transfer. */
00626     int bit_rate;
00627     /*! \brief TRUE if error correcting mode is used. */
00628     int error_correcting_mode;
00629     /*! \brief The number of pages transferred so far. */
00630     int pages_transferred;
00631     /*! \brief The number of pages in the file (<0 if not known). */
00632     int pages_in_file;
00633     /*! \brief The number of horizontal pixels in the most recent page. */
00634     int width;
00635     /*! \brief The number of vertical pixels in the most recent page. */
00636     int length;
00637     /*! \brief The number of bad pixel rows in the most recent page. */
00638     int bad_rows;
00639     /*! \brief The largest number of bad pixel rows in a block in the most recent page. */
00640     int longest_bad_row_run;
00641     /*! \brief The horizontal column-to-column resolution of the page in pixels per metre */
00642     int x_resolution;
00643     /*! \brief The vertical row-to-row resolution of the page in pixels per metre */
00644     int y_resolution;
00645     /*! \brief The type of compression used between the FAX machines */
00646     int encoding;
00647     /*! \brief The size of the image, in bytes */
00648     int image_size;
00649     /*! \brief Current status */
00650     int current_status;
00651 } t30_stats_t;
00652 
00653 #if defined(__cplusplus)
00654 extern "C"
00655 {
00656 #endif
00657 
00658 /*! Initialise a T.30 context.
00659     \brief Initialise a T.30 context.
00660     \param s The T.30 context.
00661     \param calling_party TRUE if the context is for a calling party. FALSE if the
00662            context is for an answering party.
00663     \param set_rx_type_handler
00664     \param set_rx_type_user_data
00665     \param set_tx_type_handler
00666     \param set_tx_type_user_data
00667     \param send_hdlc_handler
00668     \param send_hdlc_user_data
00669     \return A pointer to the context, or NULL if there was a problem. */
00670 t30_state_t *t30_init(t30_state_t *s,
00671                       int calling_party,
00672                       t30_set_handler_t *set_rx_type_handler,
00673                       void *set_rx_type_user_data,
00674                       t30_set_handler_t *set_tx_type_handler,
00675                       void *set_tx_type_user_data,
00676                       t30_send_hdlc_handler_t *send_hdlc_handler,
00677                       void *send_hdlc_user_data);
00678 
00679 /*! Release a T.30 context.
00680     \brief Release a T.30 context.
00681     \param s The T.30 context.
00682     \return 0 for OK, else -1. */
00683 int t30_release(t30_state_t *s);
00684 
00685 /*! Free a T.30 context.
00686     \brief Free a T.30 context.
00687     \param s The T.30 context.
00688     \return 0 for OK, else -1. */
00689 int t30_free(t30_state_t *s);
00690 
00691 /*! Restart a T.30 context.
00692     \brief Restart a T.30 context.
00693     \param s The T.30 context.
00694     \return 0 for OK, else -1. */
00695 int t30_restart(t30_state_t *s);
00696 
00697 /*! Cleanup a T.30 context if the call terminates.
00698     \brief Cleanup a T.30 context if the call terminates.
00699     \param s The T.30 context. */
00700 void t30_terminate(t30_state_t *s);
00701 
00702 /*! Return a text name for a T.30 frame type.
00703     \brief Return a text name for a T.30 frame type.
00704     \param x The frametype octet.
00705     \return A pointer to the text name for the frame type. If the frame type is
00706             not value, the string "???" is returned. */
00707 const char *t30_frametype(uint8_t x);
00708 
00709 /*! Decode a DIS, DTC or DCS frame, and log the contents.
00710     \brief Decode a DIS, DTC or DCS frame, and log the contents.
00711     \param s The T.30 context.
00712     \param dis A pointer to the frame to be decoded.
00713     \param len The length of the frame. */
00714 void t30_decode_dis_dtc_dcs(t30_state_t *s, const uint8_t *dis, int len);
00715 
00716 /*! Convert a phase E completion code to a short text description.
00717     \brief Convert a phase E completion code to a short text description.
00718     \param result The result code.
00719     \return A pointer to the description. */
00720 const char *t30_completion_code_to_str(int result);
00721 
00722 /*! Set Internet aware FAX (IAF) mode.
00723     \brief Set Internet aware FAX (IAF) mode.
00724     \param s The T.30 context.
00725     \param iaf TRUE for IAF, or FALSE for non-IAF. */
00726 void t30_set_iaf_mode(t30_state_t *s, int iaf);
00727 
00728 /*! Set the header information associated with a T.30 context.
00729     \brief Set the header information associated with a T.30 context.
00730     \param s The T.30 context.
00731     \param info A pointer to the information string.
00732     \return 0 for OK, else -1. */
00733 int t30_set_header_info(t30_state_t *s, const char *info);
00734 
00735 /*! Set the sub-address associated with a T.30 context.
00736     \brief Set the sub-address associated with a T.30 context.
00737     \param s The T.30 context.
00738     \param sub_address A pointer to the sub-address.
00739     \return 0 for OK, else -1. */
00740 int t30_set_local_sub_address(t30_state_t *s, const char *sub_address);
00741 
00742 /*! Set the local password (i.e. the one we expect to be given by the far
00743     end) associated with a T.30 context.
00744     \brief Set the local password associated with a T.30 context.
00745     \param s The T.30 context.
00746     \param password A pointer to the password.
00747     \return 0 for OK, else -1. */
00748 int t30_set_local_password(t30_state_t *s, const char *password);
00749 
00750 /*! Set the far password (i.e. the one we will send to the far
00751     end) associated with a T.30 context.
00752     \brief Set the far password associated with a T.30 context.
00753     \param s The T.30 context.
00754     \param password A pointer to the password.
00755     \return 0 for OK, else -1. */
00756 int t30_set_far_password(t30_state_t *s, const char *password);
00757 
00758 /*! Set the local identifier associated with a T.30 context.
00759     \brief Set the local identifier associated with a T.30 context.
00760     \param s The T.30 context.
00761     \param id A pointer to the identifier.
00762     \return 0 for OK, else -1. */
00763 int t30_set_local_ident(t30_state_t *s, const char *id);
00764 
00765 /*! Set an NSF frame to be associated with a T.30 context.
00766     \brief Set an NSF frame to be associated with a T.30 context.
00767     \param s The T.30 context.
00768     \param nsf A pointer to the frame.
00769     \param len The length of the frame.
00770     \return 0 for OK, else -1. */
00771 int t30_set_local_nsf(t30_state_t *s, const uint8_t *nsf, int len);
00772 
00773 /*! Get the header information associated with a T.30 context.
00774     \brief Get the header information associated with a T.30 context.
00775     \param s The T.30 context.
00776     \param info A pointer to a buffer for the header information.  The buffer
00777            should be at least 51 bytes long.
00778     \return the length of the string. */
00779 size_t t30_get_header_info(t30_state_t *s, char *info);
00780 
00781 /*! Get the local sub-address associated with a T.30 context.
00782     \brief Get the local sub-address associated with a T.30 context.
00783     \param s The T.30 context.
00784     \param sub_address A pointer to a buffer for the sub-address.  The buffer
00785            should be at least 21 bytes long.
00786     \return the length of the string. */
00787 size_t t30_get_local_sub_address(t30_state_t *s, char *sub_address);
00788 
00789 /*! Get the far sub-address associated with a T.30 context.
00790     \brief Get the far sub-address associated with a T.30 context.
00791     \param s The T.30 context.
00792     \param sub_address A pointer to a buffer for the sub-address.  The buffer
00793            should be at least 21 bytes long.
00794     \return the length of the string. */
00795 size_t t30_get_far_sub_address(t30_state_t *s, char *sub_address);
00796 
00797 /*! Get the local password associated with a T.30 context.
00798     \brief Get the local password associated with a T.30 context.
00799     \param s The T.30 context.
00800     \param password A pointer to a buffer for the password.  The buffer
00801            should be at least 21 bytes long.
00802     \return the length of the string. */
00803 size_t t30_get_local_password(t30_state_t *s, char *password);
00804 
00805 /*! Get the far password associated with a T.30 context.
00806     \brief Get the far password associated with a T.30 context.
00807     \param s The T.30 context.
00808     \param password A pointer to a buffer for the password.  The buffer
00809            should be at least 21 bytes long.
00810     \return the length of the string. */
00811 size_t t30_get_far_password(t30_state_t *s, char *password);
00812 
00813 /*! Get the received password associated with a T.30 context.
00814     \brief Get the received password associated with a T.30 context.
00815     \param s The T.30 context.
00816     \param password A pointer to a buffer for the password.  The buffer
00817            should be at least 21 bytes long.
00818     \return the length of the string. */
00819 size_t t30_get_received_password(t30_state_t *s, char *password);
00820 
00821 /*! Get the local FAX machine identifier associated with a T.30 context.
00822     \brief Get the local identifier associated with a T.30 context.
00823     \param s The T.30 context.
00824     \param id A pointer to a buffer for the identifier. The buffer should
00825            be at least 21 bytes long.
00826     \return the length of the string. */
00827 size_t t30_get_local_ident(t30_state_t *s, char *id);
00828 
00829 /*! Get the remote FAX machine identifier associated with a T.30 context.
00830     \brief Get the remote identifier associated with a T.30 context.
00831     \param s The T.30 context.
00832     \param id A pointer to a buffer for the identifier. The buffer should
00833            be at least 21 bytes long.
00834     \return the length of the string. */
00835 size_t t30_get_far_ident(t30_state_t *s, char *id);
00836 
00837 /*! Get the country of origin of the remote FAX machine associated with a T.30 context.
00838     \brief Get the country of origin of the remote FAX machine associated with a T.30 context.
00839     \param s The T.30 context.
00840     \return a pointer to the country name, or NULL if the country is not known. */
00841 const char *t30_get_far_country(t30_state_t *s);
00842 
00843 /*! Get the name of the vendor of the remote FAX machine associated with a T.30 context.
00844     \brief Get the name of the vendor of the remote FAX machine associated with a T.30 context.
00845     \param s The T.30 context.
00846     \return a pointer to the vendor name, or NULL if the vendor is not known. */
00847 const char *t30_get_far_vendor(t30_state_t *s);
00848 
00849 /*! Get the name of the model of the remote FAX machine associated with a T.30 context.
00850     \brief Get the name of the model of the remote FAX machine associated with a T.30 context.
00851     \param s The T.30 context.
00852     \return a pointer to the model name, or NULL if the model is not known. */
00853 const char *t30_get_far_model(t30_state_t *s);
00854 
00855 /*! Get the current transfer statistics for the file being sent or received.
00856     \brief Get the current transfer statistics.
00857     \param s The T.30 context.
00858     \param t A pointer to a buffer for the statistics. */
00859 void t30_get_transfer_statistics(t30_state_t *s, t30_stats_t *t);
00860 
00861 /*! Set a callback function for T.30 phase B handling.
00862     \brief Set a callback function for T.30 phase B handling.
00863     \param s The T.30 context.
00864     \param handler The callback function
00865     \param user_data An opaque pointer passed to the callback function. */
00866 void t30_set_phase_b_handler(t30_state_t *s, t30_phase_b_handler_t *handler, void *user_data);
00867 
00868 /*! Set a callback function for T.30 phase D handling.
00869     \brief Set a callback function for T.30 phase D handling.
00870     \param s The T.30 context.
00871     \param handler The callback function
00872     \param user_data An opaque pointer passed to the callback function. */
00873 void t30_set_phase_d_handler(t30_state_t *s, t30_phase_d_handler_t *handler, void *user_data);
00874 
00875 /*! Set a callback function for T.30 phase E handling.
00876     \brief Set a callback function for T.30 phase E handling.
00877     \param s The T.30 context.
00878     \param handler The callback function
00879     \param user_data An opaque pointer passed to the callback function. */
00880 void t30_set_phase_e_handler(t30_state_t *s, t30_phase_e_handler_t *handler, void *user_data);
00881 
00882 /*! Set a callback function for T.30 end of document handling.
00883     \brief Set a callback function for T.30 end of document handling.
00884     \param s The T.30 context.
00885     \param handler The callback function
00886     \param user_data An opaque pointer passed to the callback function. */
00887 void t30_set_document_handler(t30_state_t *s, t30_document_handler_t *handler, void *user_data);
00888 
00889 /*! Specify the file name of the next TIFF file to be received by a T.30
00890     context.
00891     \brief Set next receive file name.
00892     \param s The T.30 context.
00893     \param file The file name
00894     \param stop_page The maximum page to receive. -1 for no restriction. */
00895 void t30_set_rx_file(t30_state_t *s, const char *file, int stop_page);
00896 
00897 /*! Specify the file name of the next TIFF file to be transmitted by a T.30
00898     context.
00899     \brief Set next transmit file name.
00900     \param s The T.30 context.
00901     \param file The file name
00902     \param start_page The first page to send. -1 for no restriction.
00903     \param stop_page The last page to send. -1 for no restriction. */
00904 void t30_set_tx_file(t30_state_t *s, const char *file, int start_page, int stop_page);
00905 
00906 /*! Specify which modem types are supported by a T.30 context.
00907     \brief Specify supported modems.
00908     \param s The T.30 context.
00909     \param supported_modems Bit field list of the supported modems.
00910     \return 0 if OK, else -1. */
00911 int t30_set_supported_modems(t30_state_t *s, int supported_modems);
00912 
00913 /*! Specify a period of responding with receiver not ready.
00914     \brief Specify a period of responding with receiver not ready.
00915     \param s The T.30 context.
00916     \param count The number of times to report receiver not ready.
00917     \return 0 if OK, else -1. */
00918 int t30_set_receiver_not_ready(t30_state_t *s, int count);
00919 
00920 /*! Specify which compression types are supported by a T.30 context.
00921     \brief Specify supported compression types.
00922     \param s The T.30 context.
00923     \param supported_compressions Bit field list of the supported compression types.
00924     \return 0 if OK, else -1. */
00925 int t30_set_supported_compressions(t30_state_t *s, int supported_compressions);
00926 
00927 /*! Specify which resolutions are supported by a T.30 context.
00928     \brief Specify supported resolutions.
00929     \param s The T.30 context.
00930     \param supported_resolutions Bit field list of the supported resolutions.
00931     \return 0 if OK, else -1. */
00932 int t30_set_supported_resolutions(t30_state_t *s, int supported_resolutions);
00933 
00934 /*! Specify which images sizes are supported by a T.30 context.
00935     \brief Specify supported image sizes.
00936     \param s The T.30 context.
00937     \param supported_image_sizes Bit field list of the supported widths and lengths.
00938     \return 0 if OK, else -1. */
00939 int t30_set_supported_image_sizes(t30_state_t *s, int supported_image_sizes);
00940 
00941 /*! Specify if error correction mode (ECM) is allowed by a T.30 context.
00942     \brief Select ECM capability.
00943     \param s The T.30 context.
00944     \param enabled TRUE for ECM capable, FALSE for not ECM capable.
00945     \return 0 if OK, else -1. */
00946 int t30_set_ecm_capability(t30_state_t *s, int enabled);
00947 
00948 /*! Specify the output encoding for TIFF files created during FAX reception.
00949     \brief Specify the output encoding for TIFF files created during FAX reception.
00950     \param s The T.30 context.
00951     \param encoding The coding required. The options are T4_COMPRESSION_ITU_T4_1D,
00952            T4_COMPRESSION_ITU_T4_2D, T4_COMPRESSION_ITU_T6. T6 is usually the
00953            densest option, but support for it is broken in a number of software
00954            packages.
00955     \return 0 if OK, else -1. */
00956 int t30_set_rx_encoding(t30_state_t *s, int encoding);
00957 
00958 /*! Request a local interrupt of FAX exchange.
00959     \brief Request a local interrupt of FAX exchange.
00960     \param s The T.30 context.
00961     \param state TRUE to enable interrupt request, else FALSE. */
00962 void t30_local_interrupt_request(t30_state_t *s, int state);
00963 
00964 /*! Inform the T.30 engine of a status change in the front end (end of tx, rx signal change, etc.).
00965     \brief Inform the T.30 engine of a status change in the front end (end of tx, rx signal change, etc.).
00966     \param user_data The T.30 context.
00967     \param status The type of status change which occured. */
00968 void t30_front_end_status(void *user_data, int status);
00969 
00970 /*! Get a bit of received non-ECM image data.
00971     \brief Get a bit of received non-ECM image data.
00972     \param user_data An opaque pointer, which must point to the T.30 context.
00973     \return The next bit to transmit. */
00974 int t30_non_ecm_get_bit(void *user_data);
00975 
00976 /*! Get a byte of received non-ECM image data.
00977     \brief Get a byte of received non-ECM image data.
00978     \param user_data An opaque pointer, which must point to the T.30 context.
00979     \return The next byte to transmit. */
00980 int t30_non_ecm_get_byte(void *user_data);
00981 
00982 /*! Get a chunk of received non-ECM image data.
00983     \brief Get a bit of received non-ECM image data.
00984     \param user_data An opaque pointer, which must point to the T.30 context.
00985     \param buf The buffer to contain the data.
00986     \param max_len The maximum length of the chunk.
00987     \return The actual length of the chunk. */
00988 int t30_non_ecm_get_chunk(void *user_data, uint8_t buf[], int max_len);
00989 
00990 /*! Process a bit of received non-ECM image data.
00991     \brief Process a bit of received non-ECM image data
00992     \param user_data An opaque pointer, which must point to the T.30 context.
00993     \param bit The received bit. */
00994 void t30_non_ecm_put_bit(void *user_data, int bit);
00995 
00996 /*! Process a byte of received non-ECM image data.
00997     \brief Process a byte of received non-ECM image data
00998     \param user_data An opaque pointer, which must point to the T.30 context.
00999     \param byte The received byte. */
01000 void t30_non_ecm_put_byte(void *user_data, int byte);
01001 
01002 /*! Process a chunk of received non-ECM image data.
01003     \brief Process a chunk of received non-ECM image data
01004     \param user_data An opaque pointer, which must point to the T.30 context.
01005     \param buf The buffer containing the received data.
01006     \param len The length of the data in buf. */
01007 void t30_non_ecm_put_chunk(void *user_data, const uint8_t buf[], int len);
01008 
01009 /*! Process a received HDLC frame.
01010     \brief Process a received HDLC frame.
01011     \param user_data The T.30 context.
01012     \param msg The HDLC message.
01013     \param len The length of the message, in octets.
01014     \param ok TRUE if the frame was received without error. */
01015 void t30_hdlc_accept(void *user_data, const uint8_t *msg, int len, int ok);
01016 
01017 /*! Report the passage of time to the T.30 engine.
01018     \brief Report the passage of time to the T.30 engine.
01019     \param s The T.30 context.
01020     \param samples The time change in 1/8000th second steps. */
01021 void t30_timer_update(t30_state_t *s, int samples);
01022 
01023 #if defined(__cplusplus)
01024 }
01025 #endif
01026 
01027 #endif
01028 /*- End of file ------------------------------------------------------------*/

Generated on Thu Mar 20 17:20:25 2008 for libspandsp by  doxygen 1.5.5