1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
|
/* GStreamer
* Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <gst/audio/audio.h>
int
gst_audio_frame_byte_size (GstPad* pad)
{
/* calculate byte size of an audio frame
* this should be moved closer to the gstreamer core
* and be implemented for every mime type IMO
* returns 0 if there's an error, or the byte size if everything's ok
*/
int width = 0;
int channels = 0;
GstCaps *caps = NULL;
/* get caps of pad */
caps = GST_PAD_CAPS (pad);
if (caps == NULL)
/* ERROR: could not get caps of pad */
return 0;
width = gst_caps_get_int (caps, "width");
channels = gst_caps_get_int (caps, "channels");
return (width / 8) * channels;
}
long
gst_audio_frame_length (GstPad* pad, GstBuffer* buf)
/* calculate length of buffer in frames
* this should be moved closer to the gstreamer core
* and be implemented for every mime type IMO
* returns 0 if there's an error, or the number of frames if everything's ok
*/
{
int frame_byte_size = 0;
frame_byte_size = gst_audio_frame_byte_size (pad);
if (frame_byte_size == 0)
/* error */
return 0;
/* FIXME: this function assumes the buffer size to be a whole multiple
* of the frame byte size
*/
return GST_BUFFER_SIZE (buf) / frame_byte_size;
}
long
gst_audio_frame_rate (GstPad *pad)
/*
* calculate frame rate (based on caps of pad)
* returns 0 if failed, rate if success
*/
{
GstCaps *caps = NULL;
/* get caps of pad */
caps = GST_PAD_CAPS (pad);
if (caps == NULL)
/* ERROR: could not get caps of pad */
return 0;
else
return gst_caps_get_int (caps, "rate");
}
double
gst_audio_length (GstPad* pad, GstBuffer* buf)
{
/* calculate length in seconds
* of audio buffer buf
* based on capabilities of pad
*/
long bytes = 0;
int width = 0;
int channels = 0;
long rate = 0L;
double length;
GstCaps *caps = NULL;
/* get caps of pad */
caps = GST_PAD_CAPS (pad);
if (caps == NULL)
{
/* ERROR: could not get caps of pad */
length = 0.0;
}
else
{
bytes = GST_BUFFER_SIZE (buf);
width = gst_caps_get_int (caps, "width");
channels = gst_caps_get_int (caps, "channels");
rate = gst_caps_get_int (caps, "rate");
length = (bytes * 8.0) / (double) (rate * channels * width);
}
return length;
}
long
gst_audio_highest_sample_value (GstPad* pad)
/* calculate highest possible sample value
* based on capabilities of pad
*/
{
gboolean is_signed = FALSE;
gint width = 0;
GstCaps *caps = NULL;
caps = GST_PAD_CAPS (pad);
/* FIXME : Please change this to a better warning method ! */
if (caps == NULL)
printf ("WARNING: gstaudio: could not get caps of pad !\n");
width = gst_caps_get_int (caps, "width");
is_signed = gst_caps_get_boolean (caps, "signed");
if (is_signed) --width;
/* example : 16 bit, signed : samples between -32768 and 32767 */
return ((long) (1 << width));
}
gboolean
gst_audio_is_buffer_framed (GstPad* pad, GstBuffer* buf)
/* check if the buffer size is a whole multiple of the frame size */
{
if (GST_BUFFER_SIZE (buf) % gst_audio_frame_byte_size (pad) == 0)
return TRUE;
else
return FALSE;
}
|
