Asterisk - The Open Source Telephony Project  GIT-master-0190e70
smoother.c
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1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 1999 - 2005, Digium, Inc.
5  *
6  * Mark Spencer <markster@digium.com>
7  *
8  * See http://www.asterisk.org for more information about
9  * the Asterisk project. Please do not directly contact
10  * any of the maintainers of this project for assistance;
11  * the project provides a web site, mailing lists and IRC
12  * channels for your use.
13  *
14  * This program is free software, distributed under the terms of
15  * the GNU General Public License Version 2. See the LICENSE file
16  * at the top of the source tree.
17  */
18 
19 /*! \file
20  *
21  * \brief Frame smoother manipulation routines
22  *
23  * \author Mark Spencer <markster@digium.com>
24  */
25 
26 /*** MODULEINFO
27  <support_level>core</support_level>
28  ***/
29 
30 #include "asterisk.h"
31 
32 #include "asterisk/_private.h"
33 #include "asterisk/frame.h"
34 #include "asterisk/astobj2.h"
35 #include "asterisk/time.h"
36 #include "asterisk/utils.h"
37 #include "asterisk/format.h"
38 #include "asterisk/codec.h"
39 #include "asterisk/smoother.h"
40 
41 #define SMOOTHER_SIZE 8000
42 
43 struct ast_smoother {
44  int size;
45  struct ast_format *format;
46  int flags;
48  unsigned int opt_needs_swap:1;
49  struct ast_frame f;
50  struct timeval delivery;
53  struct ast_frame *opt;
54  int len;
55 };
56 
57 static int smoother_frame_feed(struct ast_smoother *s, struct ast_frame *f, int swap)
58 {
59  if (s->flags & AST_SMOOTHER_FLAG_G729) {
60  if (s->len % 10) {
61  ast_log(LOG_NOTICE, "Dropping extra frame of G.729 since we already have a VAD frame at the end\n");
62  return 0;
63  }
64  }
65  if (swap) {
66  ast_swapcopy_samples(s->data + s->len, f->data.ptr, f->samples);
67  } else {
68  memcpy(s->data + s->len, f->data.ptr, f->datalen);
69  }
70  /* If either side is empty, reset the delivery time */
71  if (!s->len || ast_tvzero(f->delivery) || ast_tvzero(s->delivery)) { /* XXX really ? */
72  s->delivery = f->delivery;
73  }
74  s->len += f->datalen;
75 
76  return 0;
77 }
78 
79 void ast_smoother_reset(struct ast_smoother *s, int bytes)
80 {
81  ao2_cleanup(s->format);
82  memset(s, 0, sizeof(*s));
83  s->size = bytes;
84 }
85 
86 void ast_smoother_reconfigure(struct ast_smoother *s, int bytes)
87 {
88  /* if there is no change, then nothing to do */
89  if (s->size == bytes) {
90  return;
91  }
92  /* set the new desired output size */
93  s->size = bytes;
94  /* if there is no 'optimized' frame in the smoother,
95  * then there is nothing left to do
96  */
97  if (!s->opt) {
98  return;
99  }
100  /* there is an 'optimized' frame here at the old size,
101  * but it must now be put into the buffer so the data
102  * can be extracted at the new size
103  */
105  s->opt = NULL;
106 }
107 
109 {
110  struct ast_smoother *s;
111  if (size < 1)
112  return NULL;
113  if ((s = ast_calloc(1, sizeof(*s))))
114  ast_smoother_reset(s, size);
115  return s;
116 }
117 
119 {
120  return s->flags;
121 }
122 
124 {
125  s->flags = flags;
126 }
127 
129 {
130  return (s->flags & flag);
131 }
132 
133 int __ast_smoother_feed(struct ast_smoother *s, struct ast_frame *f, int swap)
134 {
135  if (f->frametype != AST_FRAME_VOICE) {
136  ast_log(LOG_WARNING, "Huh? Can't smooth a non-voice frame!\n");
137  return -1;
138  }
139  if (!s->format) {
140  s->format = ao2_bump(f->subclass.format);
141  s->samplesperbyte = (float)f->samples / (float)f->datalen;
143  ast_log(LOG_WARNING, "Smoother was working on %s format frames, now trying to feed %s?\n",
145  return -1;
146  }
147  if (s->len + f->datalen > SMOOTHER_SIZE) {
148  ast_log(LOG_WARNING, "Out of smoother space\n");
149  return -1;
150  }
151  if (((f->datalen == s->size) ||
152  ((f->datalen < 10) && (s->flags & AST_SMOOTHER_FLAG_G729))) &&
153  !s->opt &&
154  !s->len &&
155  (f->offset >= AST_MIN_OFFSET)) {
156  /* Optimize by sending the frame we just got
157  on the next read, thus eliminating the douple
158  copy */
159  if (swap)
161  s->opt = f;
162  s->opt_needs_swap = swap ? 1 : 0;
163  return 0;
164  }
165 
166  return smoother_frame_feed(s, f, swap);
167 }
168 
170 {
171  struct ast_frame *opt;
172  int len;
173 
174  /* IF we have an optimization frame, send it */
175  if (s->opt) {
176  if (s->opt->offset < AST_FRIENDLY_OFFSET)
177  ast_log(LOG_WARNING, "Returning a frame of inappropriate offset (%d).\n",
178  s->opt->offset);
179  opt = s->opt;
180  s->opt = NULL;
181  return opt;
182  }
183 
184  /* Make sure we have enough data */
185  if (s->len < s->size) {
186  /* Or, if this is a G.729 frame with VAD on it, send it immediately anyway */
187  if (!((s->flags & AST_SMOOTHER_FLAG_G729) && (s->len % 10)))
188  return NULL;
189  }
190  len = s->size;
191  if (len > s->len)
192  len = s->len;
193  /* Make frame */
195  s->f.subclass.format = s->format;
198  s->f.datalen = len;
199  /* Samples will be improper given VAD, but with VAD the concept really doesn't even exist */
200  s->f.samples = len * s->samplesperbyte; /* XXX rounding */
201  s->f.delivery = s->delivery;
202  /* Fill Data */
203  memcpy(s->f.data.ptr, s->data, len);
204  s->len -= len;
205  /* Move remaining data to the front if applicable */
206  if (s->len) {
207  /* In principle this should all be fine because if we are sending
208  G.729 VAD, the next timestamp will take over anyawy */
209  memmove(s->data, s->data + len, s->len);
210  if (!ast_tvzero(s->delivery)) {
211  /* If we have delivery time, increment it, otherwise, leave it at 0 */
214  }
215  }
216  /* Return frame */
217  return &s->f;
218 }
219 
221 {
222  ao2_cleanup(s->format);
223  ast_free(s);
224 }
int ast_smoother_test_flag(struct ast_smoother *s, int flag)
Definition: smoother.c:128
Asterisk main include file. File version handling, generic pbx functions.
#define AST_SMOOTHER_FLAG_G729
Definition: smoother.h:34
struct ast_frame * ast_smoother_read(struct ast_smoother *s)
Definition: smoother.c:169
Time-related functions and macros.
int ast_smoother_get_flags(struct ast_smoother *s)
Definition: smoother.c:118
void ast_smoother_reset(struct ast_smoother *s, int bytes)
Definition: smoother.c:79
#define LOG_WARNING
Definition: logger.h:274
union ast_frame::@257 data
int ast_tvzero(const struct timeval t)
Returns true if the argument is 0,0.
Definition: time.h:108
void ast_swapcopy_samples(void *dst, const void *src, int samples)
Definition: main/frame.c:396
Codec API.
Definition of a media format.
Definition: format.c:43
const char * ast_format_get_name(const struct ast_format *format)
Get the name associated with a format.
Definition: format.c:334
#define SMOOTHER_SIZE
Definition: smoother.c:41
struct ast_frame f
Definition: smoother.c:49
#define NULL
Definition: resample.c:96
Asterisk internal frame definitions.
struct ast_frame_subclass subclass
int __ast_smoother_feed(struct ast_smoother *s, struct ast_frame *f, int swap)
Definition: smoother.c:133
Utility functions.
#define AST_MIN_OFFSET
Media Format API.
void ast_smoother_set_flags(struct ast_smoother *s, int flags)
Definition: smoother.c:123
#define ao2_bump(obj)
Definition: astobj2.h:491
#define ast_log
Definition: astobj2.c:42
enum ast_format_cmp_res ast_format_cmp(const struct ast_format *format1, const struct ast_format *format2)
Compare two formats.
Definition: format.c:201
#define AST_FRIENDLY_OFFSET
Offset into a frame&#39;s data buffer.
static int smoother_frame_feed(struct ast_smoother *s, struct ast_frame *f, int swap)
Definition: smoother.c:57
Asterisk internal frame definitions.
struct timeval ast_samp2tv(unsigned int _nsamp, unsigned int _rate)
Returns a timeval corresponding to the duration of n samples at rate r. Useful to convert samples to ...
Definition: time.h:238
char data[SMOOTHER_SIZE]
Definition: smoother.c:51
float samplesperbyte
Definition: smoother.c:47
struct timeval delivery
Definition: smoother.c:50
struct timeval ast_tvadd(struct timeval a, struct timeval b)
Returns the sum of two timevals a + b.
Definition: extconf.c:2283
struct ast_frame * opt
Definition: smoother.c:53
#define LOG_NOTICE
Definition: logger.h:263
long int flag
Definition: f2c.h:83
void ast_smoother_reconfigure(struct ast_smoother *s, int bytes)
Reconfigure an existing smoother to output a different number of bytes per frame. ...
Definition: smoother.c:86
#define ast_free(a)
Definition: astmm.h:182
#define ast_calloc(num, len)
A wrapper for calloc()
Definition: astmm.h:204
Prototypes for public functions only of internal interest,.
struct timeval delivery
unsigned int opt_needs_swap
Definition: smoother.c:48
struct ast_format * format
Definition: smoother.c:45
#define ao2_cleanup(obj)
Definition: astobj2.h:1958
struct ast_smoother * ast_smoother_new(int size)
Definition: smoother.c:108
unsigned int ast_format_get_sample_rate(const struct ast_format *format)
Get the sample rate of a media format.
Definition: format.c:379
Data structure associated with a single frame of data.
char framedata[SMOOTHER_SIZE+AST_FRIENDLY_OFFSET]
Definition: smoother.c:52
enum ast_frame_type frametype
struct ast_format * format
void ast_smoother_free(struct ast_smoother *s)
Definition: smoother.c:220