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
153
154
155
156
157
158
|
/*
* convert.c
*/
#include "convert.h"
#include <vdr/tools.h>
/* --- cConvert ------------------------------------------------------------- */
cConvert::cConvert(const cPostData &postdata)
{
encoder_buf.data = NULL;
encoder_buf.length = 0;
encoder_open = -1;
decoder_buf.data = NULL;
decoder_buf.length = 0;
decoder_open = -1;
init_decoder();
init_encoder(audio_codecs[postdata.get_codec()], postdata.get_bit_rate(),
postdata.get_sample_rate(), postdata.get_channels());
}
cConvert::~cConvert()
{
delete[] encoder_buf.data;
delete[] decoder_buf.data;
if (decoder_open > -1) {
avcodec_close(decoder_ctx);
av_free(decoder_ctx);
}
if (encoder_open > -1) {
avcodec_close(encoder_ctx);
av_free(encoder_ctx);
}
}
void cConvert::init_decoder(void)
{
decoder_codec = avcodec_find_decoder_by_name("mp2");
if (! decoder_codec) {
dsyslog("[audiorecorder]: codec mp2 is not supported (%s, "
"%s())", __FILE__, __func__);
return;
}
decoder_ctx = avcodec_alloc_context3(NULL);
decoder_open = avcodec_open2(decoder_ctx, decoder_codec, 0);
if (decoder_open < 0) {
dsyslog("[audiorecorder]: could not open codec mp2 (%s, "
"%s())", __FILE__, __func__);
return;
}
decoder_buf.data = new uchar[AVCODEC_MAX_AUDIO_FRAME_SIZE];
dsyslog("[audiorecorder]: decoder initialized (%s, %s())", __FILE__,
__func__);
}
void cConvert::init_encoder(const char *codec, int bit_rate, int sample_rate,
int channels)
{
encoder_codec = avcodec_find_encoder_by_name(codec);
if (! encoder_codec) {
dsyslog("[audiorecorder]: codec %s is not supported (%s, "
"%s())", codec, __FILE__, __func__);
return;
}
encoder_ctx = avcodec_alloc_context3(NULL);
encoder_ctx->bit_rate = bit_rate;
encoder_ctx->sample_rate = sample_rate;
encoder_ctx->channels = channels;
encoder_open = avcodec_open(encoder_ctx, encoder_codec);
if (encoder_open < 0) {
dsyslog("[audiorecorder]: could not open codec %s (%s, %s())", codec, __FILE__, __func__);
return;
}
encoder_buf.length = encoder_ctx->frame_size;
encoder_buf.data = new uchar[encoder_buf.length];
dsyslog("[audiorecorder]: encoder for %s-codec (br: %d, sr: %d, %d ch) "
"initialized (%s, %s())", encoder_codec->name,
encoder_ctx->bit_rate, encoder_ctx->sample_rate,
encoder_ctx->channels, __FILE__, __func__);
}
void cConvert::decode_mpa_frame(mpeg_audio_frame *mpa_frame)
{
if (decoder_open < 0) {
decoder_buf.length = 0;
return;
}
#if LIBAVCODEC_VERSION_INT < ((52<<16)+(0<<8)+0)
avcodec_decode_audio(decoder_ctx, (short *)decoder_buf.data,
&decoder_buf.length, mpa_frame->data, mpa_frame->length);
#else
AVPacket avpkt;
av_init_packet(&avpkt);
avpkt.data = mpa_frame->data;
avpkt.size = mpa_frame->length;
decoder_buf.length = AVCODEC_MAX_AUDIO_FRAME_SIZE;
int len = avcodec_decode_audio3(decoder_ctx, (short *)decoder_buf.data,
&decoder_buf.length, &avpkt);
#endif
}
abuffer *cConvert::reencode_mpa_frame(mpeg_audio_frame *mpa_frame,
float volume)
{
int c, len;
short *tmp;
if (decoder_open < 0 || encoder_open < 0)
return &encoder_buf;
if (strcmp(encoder_codec->name, "mp2") == 0 && volume == 1) {
mpa_frame_buf.data = mpa_frame->data;
mpa_frame_buf.offset = mpa_frame->length;
return &mpa_frame_buf;
}
decode_mpa_frame(mpa_frame);
if (volume != 1) {
/* manipulate the volume */
len = decoder_buf.length / sizeof(short);
tmp = (short *)decoder_buf.data;
for (c = 0; c < len; ++c) {
*(tmp) = (short)((float)*(tmp) * volume);
++tmp;
}
}
encoder_buf.offset = avcodec_encode_audio(encoder_ctx, encoder_buf.data,
encoder_buf.length, (short *)decoder_buf.data);
/* encoder_buf.offset is used to save the size of the encoded frame */
return &encoder_buf;
}
|
