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frame.c

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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  *
00021  * \brief Frame manipulation routines
00022  * 
00023  */
00024 
00025 #include <stdlib.h>
00026 #include <unistd.h>
00027 #include <string.h>
00028 #include <errno.h>
00029 #include <stdio.h>
00030 
00031 #include "asterisk.h"
00032 
00033 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 33036 $")
00034 
00035 #include "asterisk/lock.h"
00036 #include "asterisk/frame.h"
00037 #include "asterisk/logger.h"
00038 #include "asterisk/options.h"
00039 #include "asterisk/channel.h"
00040 #include "asterisk/cli.h"
00041 #include "asterisk/term.h"
00042 #include "asterisk/utils.h"
00043 
00044 #ifdef TRACE_FRAMES
00045 static int headers = 0;
00046 static struct ast_frame *headerlist = NULL;
00047 AST_MUTEX_DEFINE_STATIC(framelock);
00048 #endif
00049 
00050 #define SMOOTHER_SIZE 8000
00051 
00052 #define TYPE_HIGH  0x0
00053 #define TYPE_LOW   0x1
00054 #define TYPE_SILENCE  0x2
00055 #define TYPE_DONTSEND    0x3
00056 #define TYPE_MASK  0x3
00057 
00058 struct ast_format_list {
00059    int visible;   /*!< Can we see this entry */
00060    int bits;   /*!< bitmask value */
00061    char *name; /*!< short name */
00062    char *desc; /*!< Description */
00063 };
00064 
00065 struct ast_smoother {
00066    int size;
00067    int format;
00068    int readdata;
00069    int optimizablestream;
00070    int flags;
00071    float samplesperbyte;
00072    struct ast_frame f;
00073    struct timeval delivery;
00074    char data[SMOOTHER_SIZE];
00075    char framedata[SMOOTHER_SIZE + AST_FRIENDLY_OFFSET];
00076    struct ast_frame *opt;
00077    int len;
00078 };
00079 
00080 /*! \brief Definition of supported media formats (codecs) */
00081 static struct ast_format_list AST_FORMAT_LIST[] = {
00082    { 1, AST_FORMAT_G723_1 , "g723" , "G.723.1"},   /*!< codec_g723_1.c */
00083    { 1, AST_FORMAT_GSM, "gsm" , "GSM"},      /*!< codec_gsm.c */
00084    { 1, AST_FORMAT_ULAW, "ulaw", "G.711 u-law" },  /*!< codec_ulaw.c */
00085    { 1, AST_FORMAT_ALAW, "alaw", "G.711 A-law" },  /*!< codec_alaw.c */
00086    { 1, AST_FORMAT_G726, "g726", "G.726" },  /*!< codec_g726.c */
00087    { 1, AST_FORMAT_ADPCM, "adpcm" , "ADPCM"},   /*!< codec_adpcm.c */
00088    { 1, AST_FORMAT_SLINEAR, "slin",  "16 bit Signed Linear PCM"}, /*!<  */
00089    { 1, AST_FORMAT_LPC10, "lpc10", "LPC10" },   /*!< codec_lpc10.c */
00090    { 1, AST_FORMAT_G729A, "g729", "G.729A" },   /*!< Binary commercial distribution */
00091    { 1, AST_FORMAT_SPEEX, "speex", "SpeeX" },   /*!< codec_speex.c */
00092    { 1, AST_FORMAT_ILBC, "ilbc", "iLBC"}, /*!< codec_ilbc.c */
00093    { 0, 0, "nothing", "undefined" },
00094    { 0, 0, "nothing", "undefined" },
00095    { 0, 0, "nothing", "undefined" },
00096    { 0, 0, "nothing", "undefined" },
00097    { 0, AST_FORMAT_MAX_AUDIO, "maxaudio", "Maximum audio format" },
00098    { 1, AST_FORMAT_JPEG, "jpeg", "JPEG image"}, /*!< See format_jpeg.c */
00099    { 1, AST_FORMAT_PNG, "png", "PNG image"}, /*!< Image format */
00100    { 1, AST_FORMAT_H261, "h261", "H.261 Video" },  /*!< Passthrough */
00101    { 1, AST_FORMAT_H263, "h263", "H.263 Video" },  /*!< Passthrough support, see format_h263.c */
00102    { 1, AST_FORMAT_H263_PLUS, "h263p", "H.263+ Video" }, /*!< See format_h263.c */
00103    { 0, 0, "nothing", "undefined" },
00104    { 0, 0, "nothing", "undefined" },
00105    { 0, 0, "nothing", "undefined" },
00106    { 0, 0, "nothing", "undefined" },
00107    { 0, AST_FORMAT_MAX_VIDEO, "maxvideo", "Maximum video format" },
00108 };
00109 
00110 void ast_smoother_reset(struct ast_smoother *s, int size)
00111 {
00112    memset(s, 0, sizeof(struct ast_smoother));
00113    s->size = size;
00114 }
00115 
00116 struct ast_smoother *ast_smoother_new(int size)
00117 {
00118    struct ast_smoother *s;
00119    if (size < 1)
00120       return NULL;
00121    s = malloc(sizeof(struct ast_smoother));
00122    if (s)
00123       ast_smoother_reset(s, size);
00124    return s;
00125 }
00126 
00127 int ast_smoother_get_flags(struct ast_smoother *s)
00128 {
00129    return s->flags;
00130 }
00131 
00132 void ast_smoother_set_flags(struct ast_smoother *s, int flags)
00133 {
00134    s->flags = flags;
00135 }
00136 
00137 int __ast_smoother_feed(struct ast_smoother *s, struct ast_frame *f, int swap)
00138 {
00139    if (f->frametype != AST_FRAME_VOICE) {
00140       ast_log(LOG_WARNING, "Huh?  Can't smooth a non-voice frame!\n");
00141       return -1;
00142    }
00143    if (!s->format) {
00144       s->format = f->subclass;
00145       s->samplesperbyte = (float)f->samples / (float)f->datalen;
00146    } else if (s->format != f->subclass) {
00147       ast_log(LOG_WARNING, "Smoother was working on %d format frames, now trying to feed %d?\n", s->format, f->subclass);
00148       return -1;
00149    }
00150    if (s->len + f->datalen > SMOOTHER_SIZE) {
00151       ast_log(LOG_WARNING, "Out of smoother space\n");
00152       return -1;
00153    }
00154    if (((f->datalen == s->size) || ((f->datalen < 10) && (s->flags & AST_SMOOTHER_FLAG_G729)))
00155              && !s->opt && (f->offset >= AST_MIN_OFFSET)) {
00156       if (!s->len) {
00157          /* Optimize by sending the frame we just got
00158             on the next read, thus eliminating the douple
00159             copy */
00160          s->opt = f;
00161          return 0;
00162       } else {
00163          s->optimizablestream++;
00164          if (s->optimizablestream > 10) {
00165             /* For the past 10 rounds, we have input and output
00166                frames of the correct size for this smoother, yet
00167                we were unable to optimize because there was still
00168                some cruft left over.  Lets just drop the cruft so
00169                we can move to a fully optimized path */
00170             s->len = 0;
00171             s->opt = f;
00172             return 0;
00173          }
00174       }
00175    } else 
00176       s->optimizablestream = 0;
00177    if (s->flags & AST_SMOOTHER_FLAG_G729) {
00178       if (s->len % 10) {
00179          ast_log(LOG_NOTICE, "Dropping extra frame of G.729 since we already have a VAD frame at the end\n");
00180          return 0;
00181       }
00182    }
00183    if (swap)
00184       ast_swapcopy_samples(s->data+s->len, f->data, f->samples);
00185    else
00186       memcpy(s->data + s->len, f->data, f->datalen);
00187    /* If either side is empty, reset the delivery time */
00188    if (!s->len || ast_tvzero(f->delivery) || ast_tvzero(s->delivery))   /* XXX really ? */
00189       s->delivery = f->delivery;
00190    s->len += f->datalen;
00191    return 0;
00192 }
00193 
00194 struct ast_frame *ast_smoother_read(struct ast_smoother *s)
00195 {
00196    struct ast_frame *opt;
00197    int len;
00198    /* IF we have an optimization frame, send it */
00199    if (s->opt) {
00200       if (s->opt->offset < AST_FRIENDLY_OFFSET)
00201          ast_log(LOG_WARNING, "Returning a frame of inappropriate offset (%d).",
00202                      s->opt->offset);
00203       opt = s->opt;
00204       s->opt = NULL;
00205       return opt;
00206    }
00207 
00208    /* Make sure we have enough data */
00209    if (s->len < s->size) {
00210       /* Or, if this is a G.729 frame with VAD on it, send it immediately anyway */
00211       if (!((s->flags & AST_SMOOTHER_FLAG_G729) && (s->size % 10)))
00212          return NULL;
00213    }
00214    len = s->size;
00215    if (len > s->len)
00216       len = s->len;
00217    /* Make frame */
00218    s->f.frametype = AST_FRAME_VOICE;
00219    s->f.subclass = s->format;
00220    s->f.data = s->framedata + AST_FRIENDLY_OFFSET;
00221    s->f.offset = AST_FRIENDLY_OFFSET;
00222    s->f.datalen = len;
00223    /* Samples will be improper given VAD, but with VAD the concept really doesn't even exist */
00224    s->f.samples = len * s->samplesperbyte;   /* XXX rounding */
00225    s->f.delivery = s->delivery;
00226    /* Fill Data */
00227    memcpy(s->f.data, s->data, len);
00228    s->len -= len;
00229    /* Move remaining data to the front if applicable */
00230    if (s->len) {
00231       /* In principle this should all be fine because if we are sending
00232          G.729 VAD, the next timestamp will take over anyawy */
00233       memmove(s->data, s->data + len, s->len);
00234       if (!ast_tvzero(s->delivery)) {
00235          /* If we have delivery time, increment it, otherwise, leave it at 0 */
00236          s->delivery = ast_tvadd(s->delivery, ast_samp2tv(s->f.samples, 8000));
00237       }
00238    }
00239    /* Return frame */
00240    return &s->f;
00241 }
00242 
00243 void ast_smoother_free(struct ast_smoother *s)
00244 {
00245    free(s);
00246 }
00247 
00248 static struct ast_frame *ast_frame_header_new(void)
00249 {
00250    struct ast_frame *f;
00251    f = malloc(sizeof(struct ast_frame));
00252    if (f)
00253       memset(f, 0, sizeof(struct ast_frame));
00254 #ifdef TRACE_FRAMES
00255    if (f) {
00256       headers++;
00257       f->prev = NULL;
00258       ast_mutex_lock(&framelock);
00259       f->next = headerlist;
00260       if (headerlist)
00261          headerlist->prev = f;
00262       headerlist = f;
00263       ast_mutex_unlock(&framelock);
00264    }
00265 #endif   
00266    return f;
00267 }
00268 
00269 /*!
00270  * \todo Important: I should be made more efficient.  Frame headers should
00271  * most definitely be cached
00272  */
00273 void ast_frfree(struct ast_frame *fr)
00274 {
00275    if (fr->mallocd & AST_MALLOCD_DATA) {
00276       if (fr->data) 
00277          free(fr->data - fr->offset);
00278    }
00279    if (fr->mallocd & AST_MALLOCD_SRC) {
00280       if (fr->src)
00281          free((char *)fr->src);
00282    }
00283    if (fr->mallocd & AST_MALLOCD_HDR) {
00284 #ifdef TRACE_FRAMES
00285       headers--;
00286       ast_mutex_lock(&framelock);
00287       if (fr->next)
00288          fr->next->prev = fr->prev;
00289       if (fr->prev)
00290          fr->prev->next = fr->next;
00291       else
00292          headerlist = fr->next;
00293       ast_mutex_unlock(&framelock);
00294 #endif         
00295       free(fr);
00296    }
00297 }
00298 
00299 /*!
00300  * \brief 'isolates' a frame by duplicating non-malloc'ed components
00301  * (header, src, data).
00302  * On return all components are malloc'ed
00303  */
00304 struct ast_frame *ast_frisolate(struct ast_frame *fr)
00305 {
00306    struct ast_frame *out;
00307    void *newdata;
00308 
00309    if (!(fr->mallocd & AST_MALLOCD_HDR)) {
00310       /* Allocate a new header if needed */
00311       out = ast_frame_header_new();
00312       if (!out) {
00313          ast_log(LOG_WARNING, "Out of memory\n");
00314          return NULL;
00315       }
00316       out->frametype = fr->frametype;
00317       out->subclass = fr->subclass;
00318       out->datalen = fr->datalen;
00319       out->samples = fr->samples;
00320       out->offset = fr->offset;
00321       out->src = NULL;
00322       out->data = fr->data;
00323    } else
00324       out = fr;
00325    
00326    if (!(fr->mallocd & AST_MALLOCD_SRC)) {
00327       if (fr->src) {
00328          out->src = strdup(fr->src);
00329          if (!out->src) {
00330             if (out != fr)
00331                free(out);
00332             ast_log(LOG_WARNING, "Out of memory\n");
00333             return NULL;
00334          }
00335       }
00336    } else
00337       out->src = fr->src;
00338    
00339    if (!(fr->mallocd & AST_MALLOCD_DATA))  {
00340       newdata = malloc(fr->datalen + AST_FRIENDLY_OFFSET);
00341       if (!newdata) {
00342          if (out->src != fr->src)
00343             free((void *) out->src);
00344          if (out != fr)
00345             free(out);
00346          ast_log(LOG_WARNING, "Out of memory\n");
00347          return NULL;
00348       }
00349       newdata += AST_FRIENDLY_OFFSET;
00350       out->offset = AST_FRIENDLY_OFFSET;
00351       out->datalen = fr->datalen;
00352       memcpy(newdata, fr->data, fr->datalen);
00353       out->data = newdata;
00354    }
00355 
00356    out->mallocd = AST_MALLOCD_HDR | AST_MALLOCD_SRC | AST_MALLOCD_DATA;
00357    
00358    return out;
00359 }
00360 
00361 struct ast_frame *ast_frdup(struct ast_frame *f)
00362 {
00363    struct ast_frame *out;
00364    int len, srclen = 0;
00365    void *buf;
00366    /* Start with standard stuff */
00367    len = sizeof(struct ast_frame) + AST_FRIENDLY_OFFSET + f->datalen;
00368    /* If we have a source, add space for it */
00369    /*
00370     * XXX Watch out here - if we receive a src which is not terminated
00371     * properly, we can be easily attacked. Should limit the size we deal with.
00372     */
00373    if (f->src)
00374       srclen = strlen(f->src);
00375    if (srclen > 0)
00376       len += srclen + 1;
00377    buf = malloc(len);
00378    if (!buf)
00379       return NULL;
00380    out = buf;
00381    /* Set us as having malloc'd header only, so it will eventually
00382       get freed. */
00383    out->frametype = f->frametype;
00384    out->subclass = f->subclass;
00385    out->datalen = f->datalen;
00386    out->samples = f->samples;
00387    out->delivery = f->delivery;
00388    out->mallocd = AST_MALLOCD_HDR;
00389    out->offset = AST_FRIENDLY_OFFSET;
00390    out->data = buf + sizeof(struct ast_frame) + AST_FRIENDLY_OFFSET;
00391    if (srclen > 0) {
00392       out->src = out->data + f->datalen;
00393       /* Must have space since we allocated for it */
00394       strcpy((char *)out->src, f->src);
00395    } else
00396       out->src = NULL;
00397    out->prev = NULL;
00398    out->next = NULL;
00399    memcpy(out->data, f->data, out->datalen); 
00400    return out;
00401 }
00402 
00403 #if 0
00404 /*
00405  * XXX
00406  * This function is badly broken - it does not handle correctly
00407  * partial reads on either header or body.
00408  * However is it never used anywhere so we leave it commented out
00409  */
00410 struct ast_frame *ast_fr_fdread(int fd)
00411 {
00412    char buf[65536];
00413    int res;
00414    int ttl = sizeof(struct ast_frame);
00415    struct ast_frame *f = (struct ast_frame *)buf;
00416    /* Read a frame directly from there.  They're always in the
00417       right format. */
00418    
00419    while(ttl) {
00420       res = read(fd, buf, ttl);
00421       if (res < 0) {
00422          ast_log(LOG_WARNING, "Bad read on %d: %s\n", fd, strerror(errno));
00423          return NULL;
00424       }
00425       ttl -= res;
00426    }
00427    
00428    /* read the frame header */
00429    f->mallocd = 0;
00430    /* Re-write data position */
00431    f->data = buf + sizeof(struct ast_frame);
00432    f->offset = 0;
00433    /* Forget about being mallocd */
00434    f->mallocd = 0;
00435    /* Re-write the source */
00436    f->src = (char *)__FUNCTION__;
00437    if (f->datalen > sizeof(buf) - sizeof(struct ast_frame)) {
00438       /* Really bad read */
00439       ast_log(LOG_WARNING, "Strange read (%d bytes)\n", f->datalen);
00440       return NULL;
00441    }
00442    if (f->datalen) {
00443       if ((res = read(fd, f->data, f->datalen)) != f->datalen) {
00444          /* Bad read */
00445          ast_log(LOG_WARNING, "How very strange, expected %d, got %d\n", f->datalen, res);
00446          return NULL;
00447       }
00448    }
00449    if ((f->frametype == AST_FRAME_CONTROL) && (f->subclass == AST_CONTROL_HANGUP)) {
00450       return NULL;
00451    }
00452    return ast_frisolate(f);
00453 }
00454 
00455 /* Some convenient routines for sending frames to/from stream or datagram
00456    sockets, pipes, etc (maybe even files) */
00457 
00458 /*
00459  * XXX this function is also partly broken because it does not handle
00460  * partial writes. We comment it out too, and also the unique
00461  * client it has, ast_fr_fdhangup()
00462  */
00463 int ast_fr_fdwrite(int fd, struct ast_frame *frame)
00464 {
00465    /* Write the frame exactly */
00466    if (write(fd, frame, sizeof(struct ast_frame)) != sizeof(struct ast_frame)) {
00467       ast_log(LOG_WARNING, "Write error: %s\n", strerror(errno));
00468       return -1;
00469    }
00470    if (write(fd, frame->data, frame->datalen) != frame->datalen) {
00471       ast_log(LOG_WARNING, "Write error: %s\n", strerror(errno));
00472       return -1;
00473    }
00474    return 0;
00475 }
00476 
00477 int ast_fr_fdhangup(int fd)
00478 {
00479    struct ast_frame hangup = {
00480       AST_FRAME_CONTROL,
00481       AST_CONTROL_HANGUP
00482    };
00483    return ast_fr_fdwrite(fd, &hangup);
00484 }
00485 
00486 #endif /* unused functions */
00487 void ast_swapcopy_samples(void *dst, const void *src, int samples)
00488 {
00489    int i;
00490    unsigned short *dst_s = dst;
00491    const unsigned short *src_s = src;
00492 
00493    for (i=0; i<samples; i++)
00494       dst_s[i] = (src_s[i]<<8) | (src_s[i]>>8);
00495 }
00496 
00497 
00498 struct ast_format_list *ast_get_format_list_index(int index) 
00499 {
00500    return &AST_FORMAT_LIST[index];
00501 }
00502 
00503 struct ast_format_list *ast_get_format_list(size_t *size) 
00504 {
00505    *size = (sizeof(AST_FORMAT_LIST) / sizeof(struct ast_format_list));
00506    return AST_FORMAT_LIST;
00507 }
00508 
00509 char* ast_getformatname(int format)
00510 {
00511    int x = 0;
00512    char *ret = "unknown";
00513    for (x = 0 ; x < sizeof(AST_FORMAT_LIST) / sizeof(struct ast_format_list) ; x++) {
00514       if(AST_FORMAT_LIST[x].visible && AST_FORMAT_LIST[x].bits == format) {
00515          ret = AST_FORMAT_LIST[x].name;
00516          break;
00517       }
00518    }
00519    return ret;
00520 }
00521 
00522 char *ast_getformatname_multiple(char *buf, size_t size, int format) {
00523 
00524    int x = 0;
00525    unsigned len;
00526    char *end = buf;
00527    char *start = buf;
00528    if (!size) return buf;
00529    snprintf(end, size, "0x%x (", format);
00530    len = strlen(end);
00531    end += len;
00532    size -= len;
00533    start = end;
00534    for (x = 0 ; x < sizeof(AST_FORMAT_LIST) / sizeof(struct ast_format_list) ; x++) {
00535       if (AST_FORMAT_LIST[x].visible && (AST_FORMAT_LIST[x].bits & format)) {
00536          snprintf(end, size,"%s|",AST_FORMAT_LIST[x].name);
00537          len = strlen(end);
00538          end += len;
00539          size -= len;
00540       }
00541    }
00542    if (start == end)
00543       snprintf(start, size, "nothing)");
00544    else if (size > 1)
00545       *(end -1) = ')';
00546    return buf;
00547 }
00548 
00549 static struct ast_codec_alias_table {
00550    char *alias;
00551    char *realname;
00552 
00553 } ast_codec_alias_table[] = {
00554    {"slinear","slin"},
00555    {"g723.1","g723"},
00556 };
00557 
00558 static char *ast_expand_codec_alias(char *in) {
00559    int x = 0;
00560 
00561    for (x = 0; x < sizeof(ast_codec_alias_table) / sizeof(struct ast_codec_alias_table) ; x++) {
00562       if(!strcmp(in,ast_codec_alias_table[x].alias))
00563          return ast_codec_alias_table[x].realname;
00564    }
00565    return in;
00566 }
00567 
00568 int ast_getformatbyname(char *name)
00569 {
00570    int x = 0, all = 0, format = 0;
00571 
00572    all = strcasecmp(name, "all") ? 0 : 1;
00573    for (x = 0 ; x < sizeof(AST_FORMAT_LIST) / sizeof(struct ast_format_list) ; x++) {
00574       if(AST_FORMAT_LIST[x].visible && (all || 
00575                                 !strcasecmp(AST_FORMAT_LIST[x].name,name) ||
00576                                 !strcasecmp(AST_FORMAT_LIST[x].name,ast_expand_codec_alias(name)))) {
00577          format |= AST_FORMAT_LIST[x].bits;
00578          if(!all)
00579             break;
00580       }
00581    }
00582 
00583    return format;
00584 }
00585 
00586 char *ast_codec2str(int codec) {
00587    int x = 0;
00588    char *ret = "unknown";
00589    for (x = 0 ; x < sizeof(AST_FORMAT_LIST) / sizeof(struct ast_format_list) ; x++) {
00590       if(AST_FORMAT_LIST[x].visible && AST_FORMAT_LIST[x].bits == codec) {
00591          ret = AST_FORMAT_LIST[x].desc;
00592          break;
00593       }
00594    }
00595    return ret;
00596 }
00597 
00598 static int show_codecs(int fd, int argc, char *argv[])
00599 {
00600    int i, found=0;
00601    char hex[25];
00602    
00603    if ((argc < 2) || (argc > 3))
00604       return RESULT_SHOWUSAGE;
00605 
00606    if (!option_dontwarn)
00607       ast_cli(fd, "Disclaimer: this command is for informational purposes only.\n"
00608             "\tIt does not indicate anything about your configuration.\n");
00609 
00610    ast_cli(fd, "%11s %9s %10s   TYPE   %5s   %s\n","INT","BINARY","HEX","NAME","DESC");
00611    ast_cli(fd, "--------------------------------------------------------------------------------\n");
00612    if ((argc == 2) || (!strcasecmp(argv[1],"audio"))) {
00613       found = 1;
00614       for (i=0;i<11;i++) {
00615          snprintf(hex,25,"(0x%x)",1<<i);
00616          ast_cli(fd, "%11u (1 << %2d) %10s  audio   %5s   (%s)\n",1 << i,i,hex,ast_getformatname(1<<i),ast_codec2str(1<<i));
00617       }
00618    }
00619 
00620    if ((argc == 2) || (!strcasecmp(argv[1],"image"))) {
00621       found = 1;
00622       for (i=16;i<18;i++) {
00623          snprintf(hex,25,"(0x%x)",1<<i);
00624          ast_cli(fd, "%11u (1 << %2d) %10s  image   %5s   (%s)\n",1 << i,i,hex,ast_getformatname(1<<i),ast_codec2str(1<<i));
00625       }
00626    }
00627 
00628    if ((argc == 2) || (!strcasecmp(argv[1],"video"))) {
00629       found = 1;
00630       for (i=18;i<21;i++) {
00631          snprintf(hex,25,"(0x%x)",1<<i);
00632          ast_cli(fd, "%11u (1 << %2d) %10s  video   %5s   (%s)\n",1 << i,i,hex,ast_getformatname(1<<i),ast_codec2str(1<<i));
00633       }
00634    }
00635 
00636    if (! found)
00637       return RESULT_SHOWUSAGE;
00638    else
00639       return RESULT_SUCCESS;
00640 }
00641 
00642 static char frame_show_codecs_usage[] =
00643 "Usage: show [audio|video|image] codecs\n"
00644 "       Displays codec mapping\n";
00645 
00646 static int show_codec_n(int fd, int argc, char *argv[])
00647 {
00648    int codec, i, found=0;
00649 
00650    if (argc != 3)
00651       return RESULT_SHOWUSAGE;
00652 
00653    if (sscanf(argv[2],"%d",&codec) != 1)
00654       return RESULT_SHOWUSAGE;
00655 
00656    for (i=0;i<32;i++)
00657       if (codec & (1 << i)) {
00658          found = 1;
00659          ast_cli(fd, "%11u (1 << %2d)  %s\n",1 << i,i,ast_codec2str(1<<i));
00660       }
00661 
00662    if (! found)
00663       ast_cli(fd, "Codec %d not found\n", codec);
00664 
00665    return RESULT_SUCCESS;
00666 }
00667 
00668 static char frame_show_codec_n_usage[] =
00669 "Usage: show codec <number>\n"
00670 "       Displays codec mapping\n";
00671 
00672 /*! Dump a frame for debugging purposes */
00673 void ast_frame_dump(char *name, struct ast_frame *f, char *prefix)
00674 {
00675    char *n = "unknown";
00676    char ftype[40] = "Unknown Frametype";
00677    char cft[80];
00678    char subclass[40] = "Unknown Subclass";
00679    char csub[80];
00680    char moreinfo[40] = "";
00681    char cn[60];
00682    char cp[40];
00683    char cmn[40];
00684    if (name)
00685       n = name;
00686    if (!f) {
00687       ast_verbose("%s [ %s (NULL) ] [%s]\n", 
00688          term_color(cp, prefix, COLOR_BRMAGENTA, COLOR_BLACK, sizeof(cp)),
00689          term_color(cft, "HANGUP", COLOR_BRRED, COLOR_BLACK, sizeof(cft)), 
00690          term_color(cn, n, COLOR_YELLOW, COLOR_BLACK, sizeof(cn)));
00691       return;
00692    }
00693    /* XXX We should probably print one each of voice and video when the format changes XXX */
00694    if (f->frametype == AST_FRAME_VOICE)
00695       return;
00696    if (f->frametype == AST_FRAME_VIDEO)
00697       return;
00698    switch(f->frametype) {
00699    case AST_FRAME_DTMF:
00700       strcpy(ftype, "DTMF");
00701       subclass[0] = f->subclass;
00702       subclass[1] = '\0';
00703       break;
00704    case AST_FRAME_CONTROL:
00705       strcpy(ftype, "Control");
00706       switch(f->subclass) {
00707       case AST_CONTROL_HANGUP:
00708          strcpy(subclass, "Hangup");
00709          break;
00710       case AST_CONTROL_RING:
00711          strcpy(subclass, "Ring");
00712          break;
00713       case AST_CONTROL_RINGING:
00714          strcpy(subclass, "Ringing");
00715          break;
00716       case AST_CONTROL_ANSWER:
00717          strcpy(subclass, "Answer");
00718          break;
00719       case AST_CONTROL_BUSY:
00720          strcpy(subclass, "Busy");
00721          break;
00722       case AST_CONTROL_TAKEOFFHOOK:
00723          strcpy(subclass, "Take Off Hook");
00724          break;
00725       case AST_CONTROL_OFFHOOK:
00726          strcpy(subclass, "Line Off Hook");
00727          break;
00728       case AST_CONTROL_CONGESTION:
00729          strcpy(subclass, "Congestion");
00730          break;
00731       case AST_CONTROL_FLASH:
00732          strcpy(subclass, "Flash");
00733          break;
00734       case AST_CONTROL_WINK:
00735          strcpy(subclass, "Wink");
00736          break;
00737       case AST_CONTROL_OPTION:
00738          strcpy(subclass, "Option");
00739          break;
00740       case AST_CONTROL_RADIO_KEY:
00741          strcpy(subclass, "Key Radio");
00742          break;
00743       case AST_CONTROL_RADIO_UNKEY:
00744          strcpy(subclass, "Unkey Radio");
00745          break;
00746       case -1:
00747          strcpy(subclass, "Stop generators");
00748          break;
00749       default:
00750          snprintf(subclass, sizeof(subclass), "Unknown control '%d'", f->subclass);
00751       }
00752       break;
00753    case AST_FRAME_NULL:
00754       strcpy(ftype, "Null Frame");
00755       strcpy(subclass, "N/A");
00756       break;
00757    case AST_FRAME_IAX:
00758       /* Should never happen */
00759       strcpy(ftype, "IAX Specific");
00760       snprintf(subclass, sizeof(subclass), "IAX Frametype %d", f->subclass);
00761       break;
00762    case AST_FRAME_TEXT:
00763       strcpy(ftype, "Text");
00764       strcpy(subclass, "N/A");
00765       ast_copy_string(moreinfo, f->data, sizeof(moreinfo));
00766       break;
00767    case AST_FRAME_IMAGE:
00768       strcpy(ftype, "Image");
00769       snprintf(subclass, sizeof(subclass), "Image format %s\n", ast_getformatname(f->subclass));
00770       break;
00771    case AST_FRAME_HTML:
00772       strcpy(ftype, "HTML");
00773       switch(f->subclass) {
00774       case AST_HTML_URL:
00775          strcpy(subclass, "URL");
00776          ast_copy_string(moreinfo, f->data, sizeof(moreinfo));
00777          break;
00778       case AST_HTML_DATA:
00779          strcpy(subclass, "Data");
00780          break;
00781       case AST_HTML_BEGIN:
00782          strcpy(subclass, "Begin");
00783          break;
00784       case AST_HTML_END:
00785          strcpy(subclass, "End");
00786          break;
00787       case AST_HTML_LDCOMPLETE:
00788          strcpy(subclass, "Load Complete");
00789          break;
00790       case AST_HTML_NOSUPPORT:
00791          strcpy(subclass, "No Support");
00792          break;
00793       case AST_HTML_LINKURL:
00794          strcpy(subclass, "Link URL");
00795          ast_copy_string(moreinfo, f->data, sizeof(moreinfo));
00796          break;
00797       case AST_HTML_UNLINK:
00798          strcpy(subclass, "Unlink");
00799          break;
00800       case AST_HTML_LINKREJECT:
00801          strcpy(subclass, "Link Reject");
00802          break;
00803       default:
00804          snprintf(subclass, sizeof(subclass), "Unknown HTML frame '%d'\n", f->subclass);
00805          break;
00806       }
00807       break;
00808    default:
00809       snprintf(ftype, sizeof(ftype), "Unknown Frametype '%d'", f->frametype);
00810    }
00811    if (!ast_strlen_zero(moreinfo))
00812       ast_verbose("%s [ TYPE: %s (%d) SUBCLASS: %s (%d) '%s' ] [%s]\n",  
00813          term_color(cp, prefix, COLOR_BRMAGENTA, COLOR_BLACK, sizeof(cp)),
00814          term_color(cft, ftype, COLOR_BRRED, COLOR_BLACK, sizeof(cft)),
00815          f->frametype, 
00816          term_color(csub, subclass, COLOR_BRCYAN, COLOR_BLACK, sizeof(csub)),
00817          f->subclass, 
00818          term_color(cmn, moreinfo, COLOR_BRGREEN, COLOR_BLACK, sizeof(cmn)),
00819          term_color(cn, n, COLOR_YELLOW, COLOR_BLACK, sizeof(cn)));
00820    else
00821       ast_verbose("%s [ TYPE: %s (%d) SUBCLASS: %s (%d) ] [%s]\n",  
00822          term_color(cp, prefix, COLOR_BRMAGENTA, COLOR_BLACK, sizeof(cp)),
00823          term_color(cft, ftype, COLOR_BRRED, COLOR_BLACK, sizeof(cft)),
00824          f->frametype, 
00825          term_color(csub, subclass, COLOR_BRCYAN, COLOR_BLACK, sizeof(csub)),
00826          f->subclass, 
00827          term_color(cn, n, COLOR_YELLOW, COLOR_BLACK, sizeof(cn)));
00828 
00829 }
00830 
00831 
00832 #ifdef TRACE_FRAMES
00833 static int show_frame_stats(int fd, int argc, char *argv[])
00834 {
00835    struct ast_frame *f;
00836    int x=1;
00837    if (argc != 3)
00838       return RESULT_SHOWUSAGE;
00839    ast_cli(fd, "     Framer Statistics     \n");
00840    ast_cli(fd, "---------------------------\n");
00841    ast_cli(fd, "Total allocated headers: %d\n", headers);
00842    ast_cli(fd, "Queue Dump:\n");
00843    ast_mutex_lock(&framelock);
00844    for (f=headerlist; f; f = f->next) {
00845       ast_cli(fd, "%d.  Type %d, subclass %d from %s\n", x++, f->frametype, f->subclass, f->src ? f->src : "<Unknown>");
00846    }
00847    ast_mutex_unlock(&framelock);
00848    return RESULT_SUCCESS;
00849 }
00850 
00851 static char frame_stats_usage[] =
00852 "Usage: show frame stats\n"
00853 "       Displays debugging statistics from framer\n";
00854 #endif
00855 
00856 /* Builtin Asterisk CLI-commands for debugging */
00857 static struct ast_cli_entry my_clis[] = {
00858 { { "show", "codecs", NULL }, show_codecs, "Shows codecs", frame_show_codecs_usage },
00859 { { "show", "audio", "codecs", NULL }, show_codecs, "Shows audio codecs", frame_show_codecs_usage },
00860 { { "show", "video", "codecs", NULL }, show_codecs, "Shows video codecs", frame_show_codecs_usage },
00861 { { "show", "image", "codecs", NULL }, show_codecs, "Shows image codecs", frame_show_codecs_usage },
00862 { { "show", "codec", NULL }, show_codec_n, "Shows a specific codec", frame_show_codec_n_usage },
00863 #ifdef TRACE_FRAMES
00864 { { "show", "frame", "stats", NULL }, show_frame_stats, "Shows frame statistics", frame_stats_usage },
00865 #endif
00866 };
00867 
00868 int init_framer(void)
00869 {
00870    ast_cli_register_multiple(my_clis, sizeof(my_clis)/sizeof(my_clis[0]) );
00871    return 0;   
00872 }
00873 
00874 void ast_codec_pref_convert(struct ast_codec_pref *pref, char *buf, size_t size, int right) 
00875 {
00876    int x = 0, differential = (int) 'A', mem = 0;
00877    char *from = NULL, *to = NULL;
00878 
00879    if(right) {
00880       from = pref->order;
00881       to = buf;
00882       mem = size;
00883    } else {
00884       to = pref->order;
00885       from = buf;
00886       mem = 32;
00887    }
00888 
00889    memset(to, 0, mem);
00890    for (x = 0; x < 32 ; x++) {
00891       if(!from[x])
00892          break;
00893       to[x] = right ? (from[x] + differential) : (from[x] - differential);
00894    }
00895 }
00896 
00897 int ast_codec_pref_string(struct ast_codec_pref *pref, char *buf, size_t size) 
00898 {
00899    int x = 0, codec = 0; 
00900    size_t total_len = 0, slen = 0;
00901    char *formatname = 0;
00902    
00903    memset(buf,0,size);
00904    total_len = size;
00905    buf[0] = '(';
00906    total_len--;
00907    for(x = 0; x < 32 ; x++) {
00908       if(total_len <= 0)
00909          break;
00910       if(!(codec = ast_codec_pref_index(pref,x)))
00911          break;
00912       if((formatname = ast_getformatname(codec))) {
00913          slen = strlen(formatname);
00914          if(slen > total_len)
00915             break;
00916          strncat(buf,formatname,total_len);
00917          total_len -= slen;
00918       }
00919       if(total_len && x < 31 && ast_codec_pref_index(pref , x + 1)) {
00920          strncat(buf,"|",total_len);
00921          total_len--;
00922       }
00923    }
00924    if(total_len) {
00925       strncat(buf,")",total_len);
00926       total_len--;
00927    }
00928 
00929    return size - total_len;
00930 }
00931 
00932 int ast_codec_pref_index(struct ast_codec_pref *pref, int index) 
00933 {
00934    int slot = 0;
00935 
00936    
00937    if((index >= 0) && (index < sizeof(pref->order))) {
00938       slot = pref->order[index];
00939    }
00940 
00941    return slot ? AST_FORMAT_LIST[slot-1].bits : 0;
00942 }
00943 
00944 /*! \brief ast_codec_pref_remove: Remove codec from pref list ---*/
00945 void ast_codec_pref_remove(struct ast_codec_pref *pref, int format)
00946 {
00947    struct ast_codec_pref oldorder;
00948    int x=0, y=0;
00949    size_t size = 0;
00950    int slot = 0;
00951 
00952    if(!pref->order[0])
00953       return;
00954 
00955    size = sizeof(AST_FORMAT_LIST) / sizeof(struct ast_format_list);
00956 
00957    memcpy(&oldorder,pref,sizeof(struct ast_codec_pref));
00958    memset(pref,0,sizeof(struct ast_codec_pref));
00959 
00960    for (x = 0; x < size; x++) {
00961       slot = oldorder.order[x];
00962       if(! slot)
00963          break;
00964       if(AST_FORMAT_LIST[slot-1].bits != format)
00965          pref->order[y++] = slot;
00966    }
00967    
00968 }
00969 
00970 /*! \brief ast_codec_pref_append: Append codec to list ---*/
00971 int ast_codec_pref_append(struct ast_codec_pref *pref, int format)
00972 {
00973    size_t size = 0;
00974    int x = 0, newindex = -1;
00975 
00976    ast_codec_pref_remove(pref, format);
00977    size = sizeof(AST_FORMAT_LIST) / sizeof(struct ast_format_list);
00978 
00979    for (x = 0; x < size; x++) {
00980       if(AST_FORMAT_LIST[x].bits == format) {
00981          newindex = x + 1;
00982          break;
00983       }
00984    }
00985 
00986    if(newindex) {
00987       for (x = 0; x < size; x++) {
00988          if(!pref->order[x]) {
00989             pref->order[x] = newindex;
00990             break;
00991          }
00992       }
00993    }
00994 
00995    return x;
00996 }
00997 
00998 
00999 /*! \brief ast_codec_choose: Pick a codec ---*/
01000 int ast_codec_choose(struct ast_codec_pref *pref, int formats, int find_best)
01001 {
01002    size_t size = 0;
01003    int x = 0, ret = 0, slot = 0;
01004 
01005    size = sizeof(AST_FORMAT_LIST) / sizeof(struct ast_format_list);
01006    for (x = 0; x < size; x++) {
01007       slot = pref->order[x];
01008 
01009       if(!slot)
01010          break;
01011       if ( formats & AST_FORMAT_LIST[slot-1].bits ) {
01012          ret = AST_FORMAT_LIST[slot-1].bits;
01013          break;
01014       }
01015    }
01016    if(ret)
01017       return ret;
01018 
01019       return find_best ? ast_best_codec(formats) : 0;
01020 }
01021 
01022 void ast_parse_allow_disallow(struct ast_codec_pref *pref, int *mask, const char *list, int allowing) 
01023 {
01024    char *parse;
01025    char *this;
01026    int format;
01027 
01028    parse = ast_strdupa(list);
01029    while ((this = strsep(&parse, ","))) {
01030       if (!(format = ast_getformatbyname(this))) {
01031          ast_log(LOG_WARNING, "Cannot %s unknown format '%s'\n", allowing ? "allow" : "disallow", this);
01032          continue;
01033       }
01034 
01035       if (mask) {
01036          if (allowing)
01037             *mask |= format;
01038          else
01039             *mask &= ~format;
01040       }
01041 
01042       if (pref) {
01043          if (strcasecmp(this, "all")) {
01044             if (allowing)
01045                ast_codec_pref_append(pref, format);
01046             else
01047                ast_codec_pref_remove(pref, format);
01048          } else if (!allowing) {
01049             memset(pref, 0, sizeof(*pref));
01050          }
01051       }
01052    }
01053 }
01054 
01055 static int g723_len(unsigned char buf)
01056 {
01057    switch(buf & TYPE_MASK) {
01058    case TYPE_DONTSEND:
01059       return 0;
01060       break;
01061    case TYPE_SILENCE:
01062       return 4;
01063       break;
01064    case TYPE_HIGH:
01065       return 24;
01066       break;
01067    case TYPE_LOW:
01068       return 20;
01069       break;
01070    default:
01071       ast_log(LOG_WARNING, "Badly encoded frame (%d)\n", buf & TYPE_MASK);
01072    }
01073    return -1;
01074 }
01075 
01076 static int g723_samples(unsigned char *buf, int maxlen)
01077 {
01078    int pos = 0;
01079    int samples = 0;
01080    int res;
01081    while(pos < maxlen) {
01082       res = g723_len(buf[pos]);
01083       if (res <= 0)
01084          break;
01085       samples += 240;
01086       pos += res;
01087    }
01088    return samples;
01089 }
01090 
01091 static unsigned char get_n_bits_at(unsigned char *data, int n, int bit)
01092 {
01093    int byte = bit / 8;       /* byte containing first bit */
01094    int rem = 8 - (bit % 8);  /* remaining bits in first byte */
01095    unsigned char ret = 0;
01096    
01097    if (n <= 0 || n > 8)
01098       return 0;
01099 
01100    if (rem < n) {
01101       ret = (data[byte] << (n - rem));
01102       ret |= (data[byte + 1] >> (8 - n + rem));
01103    } else {
01104       ret = (data[byte] >> (rem - n));
01105    }
01106 
01107    return (ret & (0xff >> (8 - n)));
01108 }
01109 
01110 static int speex_get_wb_sz_at(unsigned char *data, int len, int bit)
01111 {
01112    static int SpeexWBSubModeSz[] = {
01113       0, 36, 112, 192,
01114       352, 0, 0, 0 };
01115    int off = bit;
01116    unsigned char c;
01117 
01118    /* skip up to two wideband frames */
01119    if (((len * 8 - off) >= 5) && 
01120       get_n_bits_at(data, 1, off)) {
01121       c = get_n_bits_at(data, 3, off + 1);
01122       off += SpeexWBSubModeSz[c];
01123 
01124       if (((len * 8 - off) >= 5) && 
01125          get_n_bits_at(data, 1, off)) {
01126          c = get_n_bits_at(data, 3, off + 1);
01127          off += SpeexWBSubModeSz[c];
01128 
01129          if (((len * 8 - off) >= 5) && 
01130             get_n_bits_at(data, 1, off)) {
01131             ast_log(LOG_WARNING, "Encountered corrupt speex frame; too many wideband frames in a row.\n");
01132             return -1;
01133          }
01134       }
01135 
01136    }
01137    return off - bit;
01138 }
01139 
01140 static int speex_samples(unsigned char *data, int len)
01141 {
01142    static int SpeexSubModeSz[] = {
01143                5, 43, 119, 160,
01144       220, 300, 364, 492, 
01145       79, 0, 0, 0,
01146       0, 0, 0, 0 };
01147    static int SpeexInBandSz[] = { 
01148       1, 1, 4, 4,
01149       4, 4, 4, 4,
01150       8, 8, 16, 16,
01151       32, 32, 64, 64 };
01152    int bit = 0;
01153    int cnt = 0;
01154    int off = 0;
01155    unsigned char c;
01156 
01157    while ((len * 8 - bit) >= 5) {
01158       /* skip wideband frames */
01159       off = speex_get_wb_sz_at(data, len, bit);
01160       if (off < 0)  {
01161          ast_log(LOG_WARNING, "Had error while reading wideband frames for speex samples\n");
01162          break;
01163       }
01164       bit += off;
01165 
01166       if ((len * 8 - bit) < 5) {
01167          ast_log(LOG_WARNING, "Not enough bits remaining after wide band for speex samples.\n");
01168          break;
01169       }
01170 
01171       /* get control bits */
01172       c = get_n_bits_at(data, 5, bit);
01173       bit += 5;
01174 
01175       if (c == 15) { 
01176          /* terminator */
01177          break; 
01178       } else if (c == 14) {
01179          /* in-band signal; next 4 bits contain signal id */
01180          c = get_n_bits_at(data, 4, bit);
01181          bit += 4;
01182          bit += SpeexInBandSz[c];
01183       } else if (c == 13) {
01184          /* user in-band; next 5 bits contain msg len */
01185          c = get_n_bits_at(data, 5, bit);
01186          bit += 5;
01187          bit += c * 8;
01188       } else if (c > 8) {
01189          /* unknown */
01190          break;
01191       } else {
01192          /* skip number bits for submode (less the 5 control bits) */
01193          bit += SpeexSubModeSz[c] - 5;
01194          cnt += 160; /* new frame */
01195       }
01196    }
01197    return cnt;
01198 }
01199 
01200 int ast_codec_get_samples(struct ast_frame *f)
01201 {
01202    int samples=0;
01203    switch(f->subclass) {
01204    case AST_FORMAT_SPEEX:
01205       samples = speex_samples(f->data, f->datalen);
01206       break;
01207    case AST_FORMAT_G723_1:
01208                 samples = g723_samples(f->data, f->datalen);
01209       break;
01210    case AST_FORMAT_ILBC:
01211       samples = 240 * (f->datalen / 50);
01212       break;
01213    case AST_FORMAT_GSM:
01214       samples = 160 * (f->datalen / 33);
01215       break;
01216    case AST_FORMAT_G729A:
01217       samples = f->datalen * 8;
01218       break;
01219    case AST_FORMAT_SLINEAR:
01220       samples = f->datalen / 2;
01221       break;
01222    case AST_FORMAT_LPC10:
01223                 /* assumes that the RTP packet contains one LPC10 frame */
01224       samples = 22 * 8;
01225       samples += (((char *)(f->data))[7] & 0x1) * 8;
01226       break;
01227    case AST_FORMAT_ULAW:
01228    case AST_FORMAT_ALAW:
01229       samples = f->datalen;
01230       break;
01231    case AST_FORMAT_ADPCM:
01232    case AST_FORMAT_G726:
01233       samples = f->datalen * 2;
01234       break;
01235    default:
01236       ast_log(LOG_WARNING, "Unable to calculate samples for format %s\n", ast_getformatname(f->subclass));
01237    }
01238    return samples;
01239 }
01240 
01241 int ast_codec_get_len(int format, int samples)
01242 {
01243    int len = 0;
01244 
01245    /* XXX Still need speex, g723, and lpc10 XXX */ 
01246    switch(format) {
01247    case AST_FORMAT_ILBC:
01248       len = (samples / 240) * 50;
01249       break;
01250    case AST_FORMAT_GSM:
01251       len = (samples / 160) * 33;
01252       break;
01253    case AST_FORMAT_G729A:
01254       len = samples / 8;
01255       break;
01256    case AST_FORMAT_SLINEAR:
01257       len = samples * 2;
01258       break;
01259    case AST_FORMAT_ULAW:
01260    case AST_FORMAT_ALAW:
01261       len = samples;
01262       break;
01263    case AST_FORMAT_ADPCM:
01264    case AST_FORMAT_G726:
01265       len = samples / 2;
01266       break;
01267    default:
01268       ast_log(LOG_WARNING, "Unable to calculate sample length for format %s\n", ast_getformatname(format));
01269    }
01270 
01271    return len;
01272 }
01273 
01274 int ast_frame_adjust_volume(struct ast_frame *f, int adjustment)
01275 {
01276    int count;
01277    short *fdata = f->data;
01278    short adjust_value = abs(adjustment);
01279 
01280    if ((f->frametype != AST_FRAME_VOICE) || (f->subclass != AST_FORMAT_SLINEAR))
01281       return -1;
01282 
01283    if (!adjustment)
01284       return 0;
01285 
01286    for (count = 0; count < f->samples; count++) {
01287       if (adjustment > 0) {
01288          ast_slinear_saturated_multiply(&fdata[count], &adjust_value);
01289       } else if (adjustment < 0) {
01290          ast_slinear_saturated_divide(&fdata[count], &adjust_value);
01291       }
01292    }
01293 
01294    return 0;
01295 }
01296 
01297 int ast_frame_slinear_sum(struct ast_frame *f1, struct ast_frame *f2)
01298 {
01299    int count;
01300    short *data1, *data2;
01301 
01302    if ((f1->frametype != AST_FRAME_VOICE) || (f1->subclass != AST_FORMAT_SLINEAR))
01303       return -1;
01304 
01305    if ((f2->frametype != AST_FRAME_VOICE) || (f2->subclass != AST_FORMAT_SLINEAR))
01306       return -1;
01307 
01308    if (f1->samples != f2->samples)
01309       return -1;
01310 
01311    for (count = 0, data1 = f1->data, data2 = f2->data;
01312         count < f1->samples;
01313         count++, data1++, data2++)
01314       ast_slinear_saturated_add(data1, data2);
01315 
01316    return 0;
01317 }

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