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Last updated: Sat Feb 3 05:00:48 2007

Asterisk developer's documentation :: Codename Pineapple

---

frame.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2005, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief Frame and codec manipulation routines
 *
 * \author Mark Spencer <markster@digium.com> 
 */

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision: 51499 $")

#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>

#include "asterisk/lock.h"
#include "asterisk/frame.h"
#include "asterisk/logger.h"
#include "asterisk/options.h"
#include "asterisk/channel.h"
#include "asterisk/cli.h"
#include "asterisk/term.h"
#include "asterisk/utils.h"
#include "asterisk/threadstorage.h"
#include "asterisk/linkedlists.h"

#ifdef TRACE_FRAMES
static int headers;
static AST_LIST_HEAD_STATIC(headerlist, ast_frame);
#endif

#if !defined(LOW_MEMORY)
static void frame_cache_cleanup(void *data);

/*! \brief A per-thread cache of frame headers */
AST_THREADSTORAGE_CUSTOM(frame_cache, NULL, frame_cache_cleanup);

/*! 
 * \brief Maximum ast_frame cache size
 *
 * In most cases where the frame header cache will be useful, the size
 * of the cache will stay very small.  However, it is not always the case that
 * the same thread that allocates the frame will be the one freeing them, so
 * sometimes a thread will never have any frames in its cache, or the cache
 * will never be pulled from.  For the latter case, we limit the maximum size. 
 */ 
#define FRAME_CACHE_MAX_SIZE  10

/*! \brief This is just so ast_frames, a list head struct for holding a list of
 *  ast_frame structures, is defined. */
AST_LIST_HEAD_NOLOCK(ast_frames, ast_frame);

struct ast_frame_cache {
   struct ast_frames list;
   size_t size;
};
#endif

#define SMOOTHER_SIZE 8000

enum frame_type {
   TYPE_HIGH,     /* 0x0 */
   TYPE_LOW,      /* 0x1 */
   TYPE_SILENCE,  /* 0x2 */
   TYPE_DONTSEND  /* 0x3 */
};

#define TYPE_MASK 0x3

struct ast_smoother {
   int size;
   int format;
   int readdata;
   int optimizablestream;
   int flags;
   float samplesperbyte;
   struct ast_frame f;
   struct timeval delivery;
   char data[SMOOTHER_SIZE];
   char framedata[SMOOTHER_SIZE + AST_FRIENDLY_OFFSET];
   struct ast_frame *opt;
   int len;
};

/*! \brief Definition of supported media formats (codecs) */
static struct ast_format_list AST_FORMAT_LIST[] = {               /*!< Bit number: comment  - Bit numbers are hard coded in show_codec() */
   { 1, AST_FORMAT_G723_1 , "g723" , "G.723.1", 20, 30, 300, 30, 30 },  /*!<  1 */
   { 1, AST_FORMAT_GSM, "gsm" , "GSM", 33, 20, 300, 20, 20 },     /*!<  2: codec_gsm.c */
   { 1, AST_FORMAT_ULAW, "ulaw", "G.711 u-law", 80, 10, 150, 10, 20 },  /*!<  3: codec_ulaw.c */
   { 1, AST_FORMAT_ALAW, "alaw", "G.711 A-law", 80, 10, 150, 10, 20 },  /*!<  4: codec_alaw.c */
   { 1, AST_FORMAT_G726, "g726", "G.726 RFC3551", 40, 10, 300, 10, 20 },   /*!<  5: codec_g726.c */
   { 1, AST_FORMAT_ADPCM, "adpcm" , "ADPCM", 40, 10, 300, 10, 20 },  /*!<  6: codec_adpcm.c */
   { 1, AST_FORMAT_SLINEAR, "slin", "16 bit Signed Linear PCM", 160, 10, 70, 10, 20, AST_SMOOTHER_FLAG_BE },   /*!< 7 */
   { 1, AST_FORMAT_LPC10, "lpc10", "LPC10", 7, 20, 20, 20, 20 },     /*!<  8: codec_lpc10.c */ 
   { 1, AST_FORMAT_G729A, "g729", "G.729A", 10, 10, 230, 10, 20, AST_SMOOTHER_FLAG_G729 },   /*!<  9: Binary commercial distribution */
   { 1, AST_FORMAT_SPEEX, "speex", "SpeeX", 10, 10, 60, 10, 20 },    /*!< 10: codec_speex.c */
   { 1, AST_FORMAT_ILBC, "ilbc", "iLBC", 50, 30, 30, 30, 30 },    /*!< 11: codec_ilbc.c */ /* inc=30ms - workaround */
   { 1, AST_FORMAT_G726_AAL2, "g726aal2", "G.726 AAL2", 40, 10, 300, 10, 20 },   /*!<  12: codec_g726.c */
   { 1, AST_FORMAT_G722, "g722", "G722"},             /*!< 13 */
   { 0, 0, "nothing", "undefined" },
   { 0, 0, "nothing", "undefined" },
   { 0, 0, "nothing", "undefined" },
   { 0, 0, "nothing", "undefined" },
   { 0, AST_FORMAT_MAX_AUDIO, "maxaudio", "Maximum audio format" },  
   { 1, AST_FORMAT_JPEG, "jpeg", "JPEG image"}, /*!< 17: See format_jpeg.c */
   { 1, AST_FORMAT_PNG, "png", "PNG image"}, /*!< 18: Image format */
   { 1, AST_FORMAT_H261, "h261", "H.261 Video" },  /*!< 19: H.261 Video Passthrough */
   { 1, AST_FORMAT_H263, "h263", "H.263 Video" },  /*!< 20: H.263 Passthrough support, see format_h263.c */
   { 1, AST_FORMAT_H263_PLUS, "h263p", "H.263+ Video" }, /*!< 21: H.263plus passthrough support See format_h263.c */
   { 1, AST_FORMAT_H264, "h264", "H.264 Video" },  /*!< 22: Passthrough support, see format_h263.c */
   { 1, AST_FORMAT_MP4_VIDEO, "mpeg4", "MPEG4 Video" }, /*!< Passthrough support for MPEG4 */
   { 0, 0, "nothing", "undefined" },
   { 0, 0, "nothing", "undefined" },
   { 0, 0, "nothing", "undefined" },
   { 0, AST_FORMAT_MAX_VIDEO, "maxvideo", "Maximum video format" },
   { 1, AST_FORMAT_T140, "t140", "Passthrough T.140 Realtime Text" },
   { 0, 0, "nothing", "undefined" },
   { 0, 0, "nothing", "undefined" },
   { 0, AST_FORMAT_MAX_TEXT, "maxtext", "Maximum text format" },
};

struct ast_frame ast_null_frame = { AST_FRAME_NULL, };

void ast_smoother_reset(struct ast_smoother *s, int size)
{
   memset(s, 0, sizeof(*s));
   s->size = size;
}

struct ast_smoother *ast_smoother_new(int size)
{
   struct ast_smoother *s;
   if (size < 1)
      return NULL;
   if ((s = ast_malloc(sizeof(*s))))
      ast_smoother_reset(s, size);
   return s;
}

int ast_smoother_get_flags(struct ast_smoother *s)
{
   return s->flags;
}

void ast_smoother_set_flags(struct ast_smoother *s, int flags)
{
   s->flags = flags;
}

int ast_smoother_test_flag(struct ast_smoother *s, int flag)
{
   return (s->flags & flag);
}

int __ast_smoother_feed(struct ast_smoother *s, struct ast_frame *f, int swap)
{
   if (f->frametype != AST_FRAME_VOICE) {
      ast_log(LOG_WARNING, "Huh?  Can't smooth a non-voice frame!\n");
      return -1;
   }
   if (!s->format) {
      s->format = f->subclass;
      s->samplesperbyte = (float)f->samples / (float)f->datalen;
   } else if (s->format != f->subclass) {
      ast_log(LOG_WARNING, "Smoother was working on %d format frames, now trying to feed %d?\n", s->format, f->subclass);
      return -1;
   }
   if (s->len + f->datalen > SMOOTHER_SIZE) {
      ast_log(LOG_WARNING, "Out of smoother space\n");
      return -1;
   }
   if (((f->datalen == s->size) || ((f->datalen < 10) && (s->flags & AST_SMOOTHER_FLAG_G729)))
             && !s->opt && (f->offset >= AST_MIN_OFFSET)) {
      if (!s->len) {
         /* Optimize by sending the frame we just got
            on the next read, thus eliminating the douple
            copy */
         if (swap)
            ast_swapcopy_samples(f->data, f->data, f->samples);
         s->opt = f;
         return 0;
      } else {
         s->optimizablestream++;
         if (s->optimizablestream > 10) {
            /* For the past 10 rounds, we have input and output
               frames of the correct size for this smoother, yet
               we were unable to optimize because there was still
               some cruft left over.  Lets just drop the cruft so
               we can move to a fully optimized path */
            if (swap)
               ast_swapcopy_samples(f->data, f->data, f->samples);
            s->len = 0;
            s->opt = f;
            return 0;
         }
      }
   } else 
      s->optimizablestream = 0;
   if (s->flags & AST_SMOOTHER_FLAG_G729) {
      if (s->len % 10) {
         ast_log(LOG_NOTICE, "Dropping extra frame of G.729 since we already have a VAD frame at the end\n");
         return 0;
      }
   }
   if (swap)
      ast_swapcopy_samples(s->data+s->len, f->data, f->samples);
   else
      memcpy(s->data + s->len, f->data, f->datalen);
   /* If either side is empty, reset the delivery time */
   if (!s->len || ast_tvzero(f->delivery) || ast_tvzero(s->delivery))   /* XXX really ? */
      s->delivery = f->delivery;
   s->len += f->datalen;
   return 0;
}

struct ast_frame *ast_smoother_read(struct ast_smoother *s)
{
   struct ast_frame *opt;
   int len;

   /* IF we have an optimization frame, send it */
   if (s->opt) {
      if (s->opt->offset < AST_FRIENDLY_OFFSET)
         ast_log(LOG_WARNING, "Returning a frame of inappropriate offset (%d).\n",
                     s->opt->offset);
      opt = s->opt;
      s->opt = NULL;
      return opt;
   }

   /* Make sure we have enough data */
   if (s->len < s->size) {
      /* Or, if this is a G.729 frame with VAD on it, send it immediately anyway */
      if (!((s->flags & AST_SMOOTHER_FLAG_G729) && (s->size % 10)))
         return NULL;
   }
   len = s->size;
   if (len > s->len)
      len = s->len;
   /* Make frame */
   s->f.frametype = AST_FRAME_VOICE;
   s->f.subclass = s->format;
   s->f.data = s->framedata + AST_FRIENDLY_OFFSET;
   s->f.offset = AST_FRIENDLY_OFFSET;
   s->f.datalen = len;
   /* Samples will be improper given VAD, but with VAD the concept really doesn't even exist */
   s->f.samples = len * s->samplesperbyte;   /* XXX rounding */
   s->f.delivery = s->delivery;
   /* Fill Data */
   memcpy(s->f.data, s->data, len);
   s->len -= len;
   /* Move remaining data to the front if applicable */
   if (s->len) {
      /* In principle this should all be fine because if we are sending
         G.729 VAD, the next timestamp will take over anyawy */
      memmove(s->data, s->data + len, s->len);
      if (!ast_tvzero(s->delivery)) {
         /* If we have delivery time, increment it, otherwise, leave it at 0 */
         s->delivery = ast_tvadd(s->delivery, ast_samp2tv(s->f.samples, 8000));
      }
   }
   /* Return frame */
   return &s->f;
}

void ast_smoother_free(struct ast_smoother *s)
{
   free(s);
}

static struct ast_frame *ast_frame_header_new(void)
{
   struct ast_frame *f;

#if !defined(LOW_MEMORY)
   struct ast_frame_cache *frames;

   if ((frames = ast_threadstorage_get(&frame_cache, sizeof(*frames)))) {
      if ((f = AST_LIST_REMOVE_HEAD(&frames->list, frame_list))) {
         size_t mallocd_len = f->mallocd_hdr_len;
         memset(f, 0, sizeof(*f));
         f->mallocd_hdr_len = mallocd_len;
         f->mallocd = AST_MALLOCD_HDR;
         frames->size--;
         return f;
      }
   }
   if (!(f = ast_calloc_cache(1, sizeof(*f))))
      return NULL;
#else
   if (!(f = ast_calloc(1, sizeof(*f))))
      return NULL;
#endif

   f->mallocd_hdr_len = sizeof(*f);
#ifdef TRACE_FRAMES
   AST_LIST_LOCK(&headerlist);
   headers++;
   AST_LIST_INSERT_HEAD(&headerlist, f, frame_list);
   AST_LIST_UNLOCK(&headerlist);
#endif   
   
   return f;
}

#if !defined(LOW_MEMORY)
static void frame_cache_cleanup(void *data)
{
   struct ast_frame_cache *frames = data;
   struct ast_frame *f;

   while ((f = AST_LIST_REMOVE_HEAD(&frames->list, frame_list)))
      free(f);
   
   free(frames);
}
#endif

void ast_frame_free(struct ast_frame *fr, int cache)
{
   if (!fr->mallocd)
      return;

#if !defined(LOW_MEMORY)
   if (cache && fr->mallocd == AST_MALLOCD_HDR) {
      /* Cool, only the header is malloc'd, let's just cache those for now 
       * to keep things simple... */
      struct ast_frame_cache *frames;

      if ((frames = ast_threadstorage_get(&frame_cache, sizeof(*frames))) 
          && frames->size < FRAME_CACHE_MAX_SIZE) {
         AST_LIST_INSERT_HEAD(&frames->list, fr, frame_list);
         frames->size++;
         return;
      }
   }
#endif
   
   if (fr->mallocd & AST_MALLOCD_DATA) {
      if (fr->data) 
         free(fr->data - fr->offset);
   }
   if (fr->mallocd & AST_MALLOCD_SRC) {
      if (fr->src)
         free((char *)fr->src);
   }
   if (fr->mallocd & AST_MALLOCD_HDR) {
#ifdef TRACE_FRAMES
      AST_LIST_LOCK(&headerlist);
      headers--;
      AST_LIST_REMOVE(&headerlist, fr, frame_list);
      AST_LIST_UNLOCK(&headerlist);
#endif         
      free(fr);
   }
}

/*!
 * \brief 'isolates' a frame by duplicating non-malloc'ed components
 * (header, src, data).
 * On return all components are malloc'ed
 */
struct ast_frame *ast_frisolate(struct ast_frame *fr)
{
   struct ast_frame *out;
   void *newdata;
   
   if (!(fr->mallocd & AST_MALLOCD_HDR)) {
      /* Allocate a new header if needed */
      if (!(out = ast_frame_header_new()))
         return NULL;
      out->frametype = fr->frametype;
      out->subclass = fr->subclass;
      out->datalen = fr->datalen;
      out->samples = fr->samples;
      out->offset = fr->offset;
      out->data = fr->data;
      /* Copy the timing data */
      out->has_timing_info = fr->has_timing_info;
      if (fr->has_timing_info) {
         out->ts = fr->ts;
         out->len = fr->len;
         out->seqno = fr->seqno;
      }
   } else
      out = fr;
   
   if (!(fr->mallocd & AST_MALLOCD_SRC)) {
      if (fr->src) {
         if (!(out->src = ast_strdup(fr->src))) {
            if (out != fr)
               free(out);
            return NULL;
         }
      }
   } else
      out->src = fr->src;
   
   if (!(fr->mallocd & AST_MALLOCD_DATA))  {
      if (!(newdata = ast_malloc(fr->datalen + AST_FRIENDLY_OFFSET))) {
         if (out->src != fr->src)
            free((void *) out->src);
         if (out != fr)
            free(out);
         return NULL;
      }
      newdata += AST_FRIENDLY_OFFSET;
      out->offset = AST_FRIENDLY_OFFSET;
      out->datalen = fr->datalen;
      memcpy(newdata, fr->data, fr->datalen);
      out->data = newdata;
   }

   out->mallocd = AST_MALLOCD_HDR | AST_MALLOCD_SRC | AST_MALLOCD_DATA;
   
   return out;
}

struct ast_frame *ast_frdup(const struct ast_frame *f)
{
   struct ast_frame *out = NULL;
   int len, srclen = 0;
   void *buf = NULL;

#if !defined(LOW_MEMORY)
   struct ast_frame_cache *frames;
#endif

   /* Start with standard stuff */
   len = sizeof(*out) + AST_FRIENDLY_OFFSET + f->datalen;
   /* If we have a source, add space for it */
   /*
    * XXX Watch out here - if we receive a src which is not terminated
    * properly, we can be easily attacked. Should limit the size we deal with.
    */
   if (f->src)
      srclen = strlen(f->src);
   if (srclen > 0)
      len += srclen + 1;
   
#if !defined(LOW_MEMORY)
   if ((frames = ast_threadstorage_get(&frame_cache, sizeof(*frames)))) {
      AST_LIST_TRAVERSE_SAFE_BEGIN(&frames->list, out, frame_list) {
         if (out->mallocd_hdr_len >= len) {
            size_t mallocd_len = out->mallocd_hdr_len;
            AST_LIST_REMOVE_CURRENT(&frames->list, frame_list);
            memset(out, 0, sizeof(*out));
            out->mallocd_hdr_len = mallocd_len;
            buf = out;
            frames->size--;
            break;
         }
      }
      AST_LIST_TRAVERSE_SAFE_END
   }
#endif

   if (!buf) {
      if (!(buf = ast_calloc_cache(1, len)))
         return NULL;
      out = buf;
      out->mallocd_hdr_len = len;
   }

   out->frametype = f->frametype;
   out->subclass = f->subclass;
   out->datalen = f->datalen;
   out->samples = f->samples;
   out->delivery = f->delivery;
   /* Set us as having malloc'd header only, so it will eventually
      get freed. */
   out->mallocd = AST_MALLOCD_HDR;
   out->offset = AST_FRIENDLY_OFFSET;
   if (out->datalen) {
      out->data = buf + sizeof(*out) + AST_FRIENDLY_OFFSET;
      memcpy(out->data, f->data, out->datalen); 
   }
   if (srclen > 0) {
      out->src = buf + sizeof(*out) + AST_FRIENDLY_OFFSET + f->datalen;
      /* Must have space since we allocated for it */
      strcpy((char *)out->src, f->src);
   }
   out->has_timing_info = f->has_timing_info;
   out->ts = f->ts;
   out->len = f->len;
   out->seqno = f->seqno;
   return out;
}

void ast_swapcopy_samples(void *dst, const void *src, int samples)
{
   int i;
   unsigned short *dst_s = dst;
   const unsigned short *src_s = src;

   for (i = 0; i < samples; i++)
      dst_s[i] = (src_s[i]<<8) | (src_s[i]>>8);
}


struct ast_format_list *ast_get_format_list_index(int index) 
{
   return &AST_FORMAT_LIST[index];
}

struct ast_format_list *ast_get_format_list(size_t *size) 
{
   *size = (sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]));
   return AST_FORMAT_LIST;
}

char* ast_getformatname(int format)
{
   int x;
   char *ret = "unknown";
   for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
      if (AST_FORMAT_LIST[x].visible && AST_FORMAT_LIST[x].bits == format) {
         ret = AST_FORMAT_LIST[x].name;
         break;
      }
   }
   return ret;
}

char *ast_getformatname_multiple(char *buf, size_t size, int format)
{
   int x;
   unsigned len;
   char *start, *end = buf;

   if (!size)
      return buf;
   snprintf(end, size, "0x%x (", format);
   len = strlen(end);
   end += len;
   size -= len;
   start = end;
   for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
      if (AST_FORMAT_LIST[x].visible && (AST_FORMAT_LIST[x].bits & format)) {
         snprintf(end, size,"%s|",AST_FORMAT_LIST[x].name);
         len = strlen(end);
         end += len;
         size -= len;
      }
   }
   if (start == end)
      snprintf(start, size, "nothing)");
   else if (size > 1)
      *(end -1) = ')';
   return buf;
}

static struct ast_codec_alias_table {
   char *alias;
   char *realname;
} ast_codec_alias_table[] = {
   { "slinear", "slin"},
   { "g723.1", "g723"},
};

static const char *ast_expand_codec_alias(const char *in)
{
   int x;

   for (x = 0; x < sizeof(ast_codec_alias_table) / sizeof(ast_codec_alias_table[0]); x++) {
      if (!strcmp(in,ast_codec_alias_table[x].alias))
         return ast_codec_alias_table[x].realname;
   }
   return in;
}

int ast_getformatbyname(const char *name)
{
   int x, all, format = 0;

   all = strcasecmp(name, "all") ? 0 : 1;
   for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
      if (AST_FORMAT_LIST[x].visible && (all || 
           !strcasecmp(AST_FORMAT_LIST[x].name,name) ||
           !strcasecmp(AST_FORMAT_LIST[x].name,ast_expand_codec_alias(name)))) {
         format |= AST_FORMAT_LIST[x].bits;
         if (!all)
            break;
      }
   }

   return format;
}

char *ast_codec2str(int codec)
{
   int x;
   char *ret = "unknown";
   for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
      if (AST_FORMAT_LIST[x].visible && AST_FORMAT_LIST[x].bits == codec) {
         ret = AST_FORMAT_LIST[x].desc;
         break;
      }
   }
   return ret;
}

static int show_codecs(int fd, int argc, char *argv[])
{
   int i, found=0;
   char hex[25];
   
   if ((argc < 3) || (argc > 4))
      return RESULT_SHOWUSAGE;

   if (!ast_opt_dont_warn)
      ast_cli(fd, "Disclaimer: this command is for informational purposes only.\n"
            "\tIt does not indicate anything about your configuration.\n");

   ast_cli(fd, "%11s %9s %10s   TYPE   %8s   %s\n","INT","BINARY","HEX","NAME","DESC");
   ast_cli(fd, "--------------------------------------------------------------------------------\n");
   if ((argc == 3) || (!strcasecmp(argv[3],"audio"))) {
      found = 1;
      for (i=0;i<13;i++) {
         snprintf(hex,25,"(0x%x)",1<<i);
         ast_cli(fd, "%11u (1 << %2d) %10s  audio   %8s   (%s)\n",1 << i,i,hex,ast_getformatname(1<<i),ast_codec2str(1<<i));
      }
   }

   if ((argc == 3) || (!strcasecmp(argv[3],"image"))) {
      found = 1;
      for (i=16;i<18;i++) {
         snprintf(hex,25,"(0x%x)",1<<i);
         ast_cli(fd, "%11u (1 << %2d) %10s  image   %8s   (%s)\n",1 << i,i,hex,ast_getformatname(1<<i),ast_codec2str(1<<i));
      }
   }

   if ((argc == 3) || (!strcasecmp(argv[3],"video"))) {
      found = 1;
      for (i=18;i<22;i++) {
         snprintf(hex,25,"(0x%x)",1<<i);
         ast_cli(fd, "%11u (1 << %2d) %10s  video   %8s   (%s)\n",1 << i,i,hex,ast_getformatname(1<<i),ast_codec2str(1<<i));
      }
   }

   if (! found)
      return RESULT_SHOWUSAGE;
   else
      return RESULT_SUCCESS;
}

static const char frame_show_codecs_usage[] =
"Usage: core show codecs [audio|video|image]\n"
"       Displays codec mapping\n";

static int show_codec_n(int fd, int argc, char *argv[])
{
   int codec, i, found=0;

   if (argc != 4)
      return RESULT_SHOWUSAGE;

   if (sscanf(argv[3],"%d",&codec) != 1)
      return RESULT_SHOWUSAGE;

   for (i = 0; i < 32; i++)
      if (codec & (1 << i)) {
         found = 1;
         ast_cli(fd, "%11u (1 << %2d)  %s\n",1 << i,i,ast_codec2str(1<<i));
      }

   if (!found)
      ast_cli(fd, "Codec %d not found\n", codec);

   return RESULT_SUCCESS;
}

static char frame_show_codec_n_usage[] =
"Usage: core show codec <number>\n"
"       Displays codec mapping\n";

/*! Dump a frame for debugging purposes */
void ast_frame_dump(const char *name, struct ast_frame *f, char *prefix)
{
   const char noname[] = "unknown";
   char ftype[40] = "Unknown Frametype";
   char cft[80];
   char subclass[40] = "Unknown Subclass";
   char csub[80];
   char moreinfo[40] = "";
   char cn[60];
   char cp[40];
   char cmn[40];

   if (!name)
      name = noname;


   if (!f) {
      ast_verbose("%s [ %s (NULL) ] [%s]\n", 
         term_color(cp, prefix, COLOR_BRMAGENTA, COLOR_BLACK, sizeof(cp)),
         term_color(cft, "HANGUP", COLOR_BRRED, COLOR_BLACK, sizeof(cft)), 
         term_color(cn, name, COLOR_YELLOW, COLOR_BLACK, sizeof(cn)));
      return;
   }
   /* XXX We should probably print one each of voice and video when the format changes XXX */
   if (f->frametype == AST_FRAME_VOICE)
      return;
   if (f->frametype == AST_FRAME_VIDEO)
      return;
   switch(f->frametype) {
   case AST_FRAME_DTMF_BEGIN:
      strcpy(ftype, "DTMF Begin");
      subclass[0] = f->subclass;
      subclass[1] = '\0';
      break;
   case AST_FRAME_DTMF_END:
      strcpy(ftype, "DTMF End");
      subclass[0] = f->subclass;
      subclass[1] = '\0';
      break;
   case AST_FRAME_CONTROL:
      strcpy(ftype, "Control");
      switch(f->subclass) {
      case AST_CONTROL_HANGUP:
         strcpy(subclass, "Hangup");
         break;
      case AST_CONTROL_RING:
         strcpy(subclass, "Ring");
         break;
      case AST_CONTROL_RINGING:
         strcpy(subclass, "Ringing");
         break;
      case AST_CONTROL_ANSWER:
         strcpy(subclass, "Answer");
         break;
      case AST_CONTROL_BUSY:
         strcpy(subclass, "Busy");
         break;
      case AST_CONTROL_TAKEOFFHOOK:
         strcpy(subclass, "Take Off Hook");
         break;
      case AST_CONTROL_OFFHOOK:
         strcpy(subclass, "Line Off Hook");
         break;
      case AST_CONTROL_CONGESTION:
         strcpy(subclass, "Congestion");
         break;
      case AST_CONTROL_FLASH:
         strcpy(subclass, "Flash");
         break;
      case AST_CONTROL_WINK:
         strcpy(subclass, "Wink");
         break;
      case AST_CONTROL_OPTION:
         strcpy(subclass, "Option");
         break;
      case AST_CONTROL_RADIO_KEY:
         strcpy(subclass, "Key Radio");
         break;
      case AST_CONTROL_RADIO_UNKEY:
         strcpy(subclass, "Unkey Radio");
         break;
      case -1:
         strcpy(subclass, "Stop generators");
         break;
      default:
         snprintf(subclass, sizeof(subclass), "Unknown control '%d'", f->subclass);
      }
      break;
   case AST_FRAME_NULL:
      strcpy(ftype, "Null Frame");
      strcpy(subclass, "N/A");
      break;
   case AST_FRAME_IAX:
      /* Should never happen */
      strcpy(ftype, "IAX Specific");
      snprintf(subclass, sizeof(subclass), "IAX Frametype %d", f->subclass);
      break;
   case AST_FRAME_TEXT:
      strcpy(ftype, "Text");
      strcpy(subclass, "N/A");
      ast_copy_string(moreinfo, f->data, sizeof(moreinfo));
      break;
   case AST_FRAME_IMAGE:
      strcpy(ftype, "Image");
      snprintf(subclass, sizeof(subclass), "Image format %s\n", ast_getformatname(f->subclass));
      break;
   case AST_FRAME_HTML:
      strcpy(ftype, "HTML");
      switch(f->subclass) {
      case AST_HTML_URL:
         strcpy(subclass, "URL");
         ast_copy_string(moreinfo, f->data, sizeof(moreinfo));
         break;
      case AST_HTML_DATA:
         strcpy(subclass, "Data");
         break;
      case AST_HTML_BEGIN:
         strcpy(subclass, "Begin");
         break;
      case AST_HTML_END:
         strcpy(subclass, "End");
         break;
      case AST_HTML_LDCOMPLETE:
         strcpy(subclass, "Load Complete");
         break;
      case AST_HTML_NOSUPPORT:
         strcpy(subclass, "No Support");
         break;
      case AST_HTML_LINKURL:
         strcpy(subclass, "Link URL");
         ast_copy_string(moreinfo, f->data, sizeof(moreinfo));
         break;
      case AST_HTML_UNLINK:
         strcpy(subclass, "Unlink");
         break;
      case AST_HTML_LINKREJECT:
         strcpy(subclass, "Link Reject");
         break;
      default:
         snprintf(subclass, sizeof(subclass), "Unknown HTML frame '%d'\n", f->subclass);
         break;
      }
      break;
   case AST_FRAME_MODEM:
      strcpy(ftype, "Modem");
      switch (f->subclass) {
      case AST_MODEM_T38:
         strcpy(subclass, "T.38");
         break;
      case AST_MODEM_V150:
         strcpy(subclass, "V.150");
         break;
      default:
         snprintf(subclass, sizeof(subclass), "Unknown MODEM frame '%d'\n", f->subclass);
         break;
      }
      break;
   default:
      snprintf(ftype, sizeof(ftype), "Unknown Frametype '%d'", f->frametype);
   }
   if (!ast_strlen_zero(moreinfo))
      ast_verbose("%s [ TYPE: %s (%d) SUBCLASS: %s (%d) '%s' ] [%s]\n",  
             term_color(cp, prefix, COLOR_BRMAGENTA, COLOR_BLACK, sizeof(cp)),
             term_color(cft, ftype, COLOR_BRRED, COLOR_BLACK, sizeof(cft)),
             f->frametype, 
             term_color(csub, subclass, COLOR_BRCYAN, COLOR_BLACK, sizeof(csub)),
             f->subclass, 
             term_color(cmn, moreinfo, COLOR_BRGREEN, COLOR_BLACK, sizeof(cmn)),
             term_color(cn, name, COLOR_YELLOW, COLOR_BLACK, sizeof(cn)));
   else
      ast_verbose("%s [ TYPE: %s (%d) SUBCLASS: %s (%d) ] [%s]\n",  
             term_color(cp, prefix, COLOR_BRMAGENTA, COLOR_BLACK, sizeof(cp)),
             term_color(cft, ftype, COLOR_BRRED, COLOR_BLACK, sizeof(cft)),
             f->frametype, 
             term_color(csub, subclass, COLOR_BRCYAN, COLOR_BLACK, sizeof(csub)),
             f->subclass, 
             term_color(cn, name, COLOR_YELLOW, COLOR_BLACK, sizeof(cn)));
}


#ifdef TRACE_FRAMES
static int show_frame_stats(int fd, int argc, char *argv[])
{
   struct ast_frame *f;
   int x=1;
   if (argc != 4)
      return RESULT_SHOWUSAGE;
   AST_LIST_LOCK(&headerlist);
   ast_cli(fd, "     Framer Statistics     \n");
   ast_cli(fd, "---------------------------\n");
   ast_cli(fd, "Total allocated headers: %d\n", headers);
   ast_cli(fd, "Queue Dump:\n");
   AST_LIST_TRAVERSE(&headerlist, f, frame_list)
      ast_cli(fd, "%d.  Type %d, subclass %d from %s\n", x++, f->frametype, f->subclass, f->src ? f->src : "<Unknown>");
   AST_LIST_UNLOCK(&headerlist);
   return RESULT_SUCCESS;
}

static const char frame_stats_usage[] =
"Usage: core show frame stats\n"
"       Displays debugging statistics from framer\n";
#endif

/* Builtin Asterisk CLI-commands for debugging */
static struct ast_cli_entry my_clis[] = {
   { { "core", "show", "codecs", NULL },
   show_codecs, "Displays a list of codecs",
   frame_show_codecs_usage },

   { { "core", "show", "audio", "codecs", NULL },
   show_codecs, "Displays a list of audio codecs",
   frame_show_codecs_usage },

   { { "core", "show", "video", "codecs", NULL },
   show_codecs, "Displays a list of video codecs",
   frame_show_codecs_usage },

   { { "core", "show", "image", "codecs", NULL },
   show_codecs, "Displays a list of image codecs",
   frame_show_codecs_usage },

   { { "core", "show", "codec", NULL },
   show_codec_n, "Shows a specific codec",
   frame_show_codec_n_usage },

#ifdef TRACE_FRAMES
   { { "core", "show", "frame", "stats", NULL },
   show_frame_stats, "Shows frame statistics",
   frame_stats_usage },
#endif
};

int init_framer(void)
{
   ast_cli_register_multiple(my_clis, sizeof(my_clis) / sizeof(struct ast_cli_entry));
   return 0;   
}

void ast_codec_pref_convert(struct ast_codec_pref *pref, char *buf, size_t size, int right) 
{
   int x, differential = (int) 'A', mem;
   char *from, *to;

   if (right) {
      from = pref->order;
      to = buf;
      mem = size;
   } else {
      to = pref->order;
      from = buf;
      mem = 32;
   }

   memset(to, 0, mem);
   for (x = 0; x < 32 ; x++) {
      if (!from[x])
         break;
      to[x] = right ? (from[x] + differential) : (from[x] - differential);
   }
}

int ast_codec_pref_string(struct ast_codec_pref *pref, char *buf, size_t size) 
{
   int x, codec; 
   size_t total_len, slen;
   char *formatname;
   
   memset(buf,0,size);
   total_len = size;
   buf[0] = '(';
   total_len--;
   for(x = 0; x < 32 ; x++) {
      if (total_len <= 0)
         break;
      if (!(codec = ast_codec_pref_index(pref,x)))
         break;
      if ((formatname = ast_getformatname(codec))) {
         slen = strlen(formatname);
         if (slen > total_len)
            break;
         strncat(buf,formatname,total_len);
         total_len -= slen;
      }
      if (total_len && x < 31 && ast_codec_pref_index(pref , x + 1)) {
         strncat(buf,"|",total_len);
         total_len--;
      }
   }
   if (total_len) {
      strncat(buf,")",total_len);
      total_len--;
   }

   return size - total_len;
}

int ast_codec_pref_index(struct ast_codec_pref *pref, int index) 
{
   int slot = 0;

   
   if ((index >= 0) && (index < sizeof(pref->order))) {
      slot = pref->order[index];
   }

   return slot ? AST_FORMAT_LIST[slot-1].bits : 0;
}

/*! \brief Remove codec from pref list */
void ast_codec_pref_remove(struct ast_codec_pref *pref, int format)
{
   struct ast_codec_pref oldorder;
   int x, y = 0;
   int slot;
   int size;

   if (!pref->order[0])
      return;

   memcpy(&oldorder, pref, sizeof(oldorder));
   memset(pref, 0, sizeof(*pref));

   for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
      slot = oldorder.order[x];
      size = oldorder.framing[x];
      if (! slot)
         break;
      if (AST_FORMAT_LIST[slot-1].bits != format) {
         pref->order[y] = slot;
         pref->framing[y++] = size;
      }
   }
   
}

/*! \brief Append codec to list */
int ast_codec_pref_append(struct ast_codec_pref *pref, int format)
{
   int x, newindex = -1;

   ast_codec_pref_remove(pref, format);

   for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
      if (AST_FORMAT_LIST[x].bits == format) {
         newindex = x + 1;
         break;
      }
   }

   if (newindex) {
      for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
         if (!pref->order[x]) {
            pref->order[x] = newindex;
            break;
         }
      }
   }

   return x;
}


/*! \brief Set packet size for codec */
int ast_codec_pref_setsize(struct ast_codec_pref *pref, int format, int framems)
{
   int x, index = -1;

   for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
      if (AST_FORMAT_LIST[x].bits == format) {
         index = x;
         break;
      }
   }

   if (index < 0)
      return -1;

   /* size validation */
   if (!framems)
      framems = AST_FORMAT_LIST[index].def_ms;

   if (AST_FORMAT_LIST[index].inc_ms && framems % AST_FORMAT_LIST[index].inc_ms) /* avoid division by zero */
      framems -= framems % AST_FORMAT_LIST[index].inc_ms;

   if (framems < AST_FORMAT_LIST[index].min_ms)
      framems = AST_FORMAT_LIST[index].min_ms;

   if (framems > AST_FORMAT_LIST[index].max_ms)
      framems = AST_FORMAT_LIST[index].max_ms;


   for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
      if (pref->order[x] == (index + 1)) {
         pref->framing[x] = framems;
         break;
      }
   }

   return x;
}

/*! \brief Get packet size for codec */
struct ast_format_list ast_codec_pref_getsize(struct ast_codec_pref *pref, int format)
{
   int x, index = -1, framems = 0;
   struct ast_format_list fmt = { 0, };

   for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
      if (AST_FORMAT_LIST[x].bits == format) {
         fmt = AST_FORMAT_LIST[x];
         index = x;
         break;
      }
   }

   for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
      if (pref->order[x] == (index + 1)) {
         framems = pref->framing[x];
         break;
      }
   }

   /* size validation */
   if (!framems)
      framems = AST_FORMAT_LIST[index].def_ms;

   if (AST_FORMAT_LIST[index].inc_ms && framems % AST_FORMAT_LIST[index].inc_ms) /* avoid division by zero */
      framems -= framems % AST_FORMAT_LIST[index].inc_ms;

   if (framems < AST_FORMAT_LIST[index].min_ms)
      framems = AST_FORMAT_LIST[index].min_ms;

   if (framems > AST_FORMAT_LIST[index].max_ms)
      framems = AST_FORMAT_LIST[index].max_ms;

   fmt.cur_ms = framems;

   return fmt;
}

/*! \brief Pick a codec */
int ast_codec_choose(struct ast_codec_pref *pref, int formats, int find_best)
{
   int x, ret = 0, slot;

   for (x = 0; x < sizeof(AST_FORMAT_LIST) / sizeof(AST_FORMAT_LIST[0]); x++) {
      slot = pref->order[x];

      if (!slot)
         break;
      if (formats & AST_FORMAT_LIST[slot-1].bits) {
         ret = AST_FORMAT_LIST[slot-1].bits;
         break;
      }
   }
   if (ret & AST_FORMAT_AUDIO_MASK)
      return ret;

   if (option_debug > 3)
      ast_log(LOG_DEBUG, "Could not find preferred codec - %s\n", find_best ? "Going for the best codec" : "Returning zero codec");

      return find_best ? ast_best_codec(formats) : 0;
}

int ast_parse_allow_disallow(struct ast_codec_pref *pref, int *mask, const char *list, int allowing) 
{
   int errors = 0;
   char *parse = NULL, *this = NULL, *psize = NULL;
   int format = 0, framems = 0;

   parse = ast_strdupa(list);
   while ((this = strsep(&parse, ","))) {
      framems = 0;
      if ((psize = strrchr(this, ':'))) {
         *psize++ = '\0';
         if (option_debug)
            ast_log(LOG_DEBUG,"Packetization for codec: %s is %s\n", this, psize);
         framems = atoi(psize);
         if (framems < 0) {
            framems = 0;
            errors++;
            ast_log(LOG_WARNING, "Bad packetization value for codec %s\n", this);
         }
      }
      if (!(format = ast_getformatbyname(this))) {
         ast_log(LOG_WARNING, "Cannot %s unknown format '%s'\n", allowing ? "allow" : "disallow", this);
         errors++;
         continue;
      }

      if (mask) {
         if (allowing)
            *mask |= format;
         else
            *mask &= ~format;
      }

      /* Set up a preference list for audio. Do not include video in preferences 
         since we can not transcode video and have to use whatever is offered
       */
      if (pref && (format & AST_FORMAT_AUDIO_MASK)) {
         if (strcasecmp(this, "all")) {
            if (allowing) {
               ast_codec_pref_append(pref, format);
               ast_codec_pref_setsize(pref, format, framems);
            }
            else
               ast_codec_pref_remove(pref, format);
         } else if (!allowing) {
            memset(pref, 0, sizeof(*pref));
         }
      }
   }
   return errors;
}

static int g723_len(unsigned char buf)
{
   enum frame_type type = buf & TYPE_MASK;

   switch(type) {
   case TYPE_DONTSEND:
      return 0;
      break;
   case TYPE_SILENCE:
      return 4;
      break;
   case TYPE_HIGH:
      return 24;
      break;
   case TYPE_LOW:
      return 20;
      break;
   default:
      ast_log(LOG_WARNING, "Badly encoded frame (%d)\n", type);
   }
   return -1;
}

static int g723_samples(unsigned char *buf, int maxlen)
{
   int pos = 0;
   int samples = 0;
   int res;
   while(pos < maxlen) {
      res = g723_len(buf[pos]);
      if (res <= 0)
         break;
      samples += 240;
      pos += res;
   }
   return samples;
}

static unsigned char get_n_bits_at(unsigned char *data, int n, int bit)
{
   int byte = bit / 8;       /* byte containing first bit */
   int rem = 8 - (bit % 8);  /* remaining bits in first byte */
   unsigned char ret = 0;
   
   if (n <= 0 || n > 8)
      return 0;

   if (rem < n) {
      ret = (data[byte] << (n - rem));
      ret |= (data[byte + 1] >> (8 - n + rem));
   } else {
      ret = (data[byte] >> (rem - n));
   }

   return (ret & (0xff >> (8 - n)));
}

static int speex_get_wb_sz_at(unsigned char *data, int len, int bit)
{
   static int SpeexWBSubModeSz[] = {
      0, 36, 112, 192,
      352, 0, 0, 0 };
   int off = bit;
   unsigned char c;

   /* skip up to two wideband frames */
   if (((len * 8 - off) >= 5) && 
      get_n_bits_at(data, 1, off)) {
      c = get_n_bits_at(data, 3, off + 1);
      off += SpeexWBSubModeSz[c];

      if (((len * 8 - off) >= 5) && 
         get_n_bits_at(data, 1, off)) {
         c = get_n_bits_at(data, 3, off + 1);
         off += SpeexWBSubModeSz[c];

         if (((len * 8 - off) >= 5) && 
            get_n_bits_at(data, 1, off)) {
            ast_log(LOG_WARNING, "Encountered corrupt speex frame; too many wideband frames in a row.\n");
            return -1;
         }
      }

   }
   return off - bit;
}

static int speex_samples(unsigned char *data, int len)
{
   static int SpeexSubModeSz[] = {
               5, 43, 119, 160,
      220, 300, 364, 492, 
      79, 0, 0, 0,
      0, 0, 0, 0 };
   static int SpeexInBandSz[] = { 
      1, 1, 4, 4,
      4, 4, 4, 4,
      8, 8, 16, 16,
      32, 32, 64, 64 };
   int bit = 0;
   int cnt = 0;
   int off;
   unsigned char c;

   while ((len * 8 - bit) >= 5) {
      /* skip wideband frames */
      off = speex_get_wb_sz_at(data, len, bit);
      if (off < 0)  {
         ast_log(LOG_WARNING, "Had error while reading wideband frames for speex samples\n");
         break;
      }
      bit += off;

      if ((len * 8 - bit) < 5) {
         ast_log(LOG_WARNING, "Not enough bits remaining after wide band for speex samples.\n");
         break;
      }

      /* get control bits */
      c = get_n_bits_at(data, 5, bit);
      bit += 5;

      if (c == 15) { 
         /* terminator */
         break; 
      } else if (c == 14) {
         /* in-band signal; next 4 bits contain signal id */
         c = get_n_bits_at(data, 4, bit);
         bit += 4;
         bit += SpeexInBandSz[c];
      } else if (c == 13) {
         /* user in-band; next 5 bits contain msg len */
         c = get_n_bits_at(data, 5, bit);
         bit += 5;
         bit += c * 8;
      } else if (c > 8) {
         /* unknown */
         break;
      } else {
         /* skip number bits for submode (less the 5 control bits) */
         bit += SpeexSubModeSz[c] - 5;
         cnt += 160; /* new frame */
      }
   }
   return cnt;
}

int ast_codec_get_samples(struct ast_frame *f)
{
   int samples=0;
   switch(f->subclass) {
   case AST_FORMAT_SPEEX:
      samples = speex_samples(f->data, f->datalen);
      break;
   case AST_FORMAT_G723_1:
                samples = g723_samples(f->data, f->datalen);
      break;
   case AST_FORMAT_ILBC:
      samples = 240 * (f->datalen / 50);
      break;
   case AST_FORMAT_GSM:
      samples = 160 * (f->datalen / 33);
      break;
   case AST_FORMAT_G729A:
      samples = f->datalen * 8;
      break;
   case AST_FORMAT_SLINEAR:
      samples = f->datalen / 2;
      break;
   case AST_FORMAT_LPC10:
                /* assumes that the RTP packet contains one LPC10 frame */
      samples = 22 * 8;
      samples += (((char *)(f->data))[7] & 0x1) * 8;
      break;
   case AST_FORMAT_ULAW:
   case AST_FORMAT_ALAW:
   case AST_FORMAT_G722:
      samples = f->datalen;
      break;
   case AST_FORMAT_ADPCM:
   case AST_FORMAT_G726:
   case AST_FORMAT_G726_AAL2:
      samples = f->datalen * 2;
      break;
   default:
      ast_log(LOG_WARNING, "Unable to calculate samples for format %s\n", ast_getformatname(f->subclass));
   }
   return samples;
}

int ast_codec_get_len(int format, int samples)
{
   int len = 0;

   /* XXX Still need speex, g723, and lpc10 XXX */ 
   switch(format) {
   case AST_FORMAT_G723_1:
      len = (samples / 240) * 20;
      break;
   case AST_FORMAT_ILBC:
      len = (samples / 240) * 50;
      break;
   case AST_FORMAT_GSM:
      len = (samples / 160) * 33;
      break;
   case AST_FORMAT_G729A:
      len = samples / 8;
      break;
   case AST_FORMAT_SLINEAR:
      len = samples * 2;
      break;
   case AST_FORMAT_ULAW:
   case AST_FORMAT_ALAW:
      len = samples;
      break;
   case AST_FORMAT_ADPCM:
   case AST_FORMAT_G726:
   case AST_FORMAT_G726_AAL2:
      len = samples / 2;
      break;
   default:
      ast_log(LOG_WARNING, "Unable to calculate sample length for format %s\n", ast_getformatname(format));
   }

   return len;
}

int ast_frame_adjust_volume(struct ast_frame *f, int adjustment)
{
   int count;
   short *fdata = f->data;
   short adjust_value = abs(adjustment);

   if ((f->frametype != AST_FRAME_VOICE) || (f->subclass != AST_FORMAT_SLINEAR))
      return -1;

   if (!adjustment)
      return 0;

   for (count = 0; count < f->samples; count++) {
      if (adjustment > 0) {
         ast_slinear_saturated_multiply(&fdata[count], &adjust_value);
      } else if (adjustment < 0) {
         ast_slinear_saturated_divide(&fdata[count], &adjust_value);
      }
   }

   return 0;
}

int ast_frame_slinear_sum(struct ast_frame *f1, struct ast_frame *f2)
{
   int count;
   short *data1, *data2;

   if ((f1->frametype != AST_FRAME_VOICE) || (f1->subclass != AST_FORMAT_SLINEAR))
      return -1;

   if ((f2->frametype != AST_FRAME_VOICE) || (f2->subclass != AST_FORMAT_SLINEAR))
      return -1;

   if (f1->samples != f2->samples)
      return -1;

   for (count = 0, data1 = f1->data, data2 = f2->data;
        count < f1->samples;
        count++, data1++, data2++)
      ast_slinear_saturated_add(data1, data2);

   return 0;
}

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