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/*
* mpa-frame.c
*/
#include "mpa-frame.h"
#include "audiorecorder.h"
#include <vdr/tools.h>
#include <iostream>
using namespace std;
const int sample_rates[] = { 44100, 48000, 32000, 0 };
const int bit_rates[] = { 0, 32000, 48000, 56000, 64000, 80000, 96000, 112000,
128000, 160000, 192000, 224000, 256000, 320000, 384000, 0 };
void get_mpa_frame(abuffer *buf, mpeg_audio_frame *mpa_frame,
const char *description)
{
int c;
mpa_frame->data = NULL;
for (c = buf->offset; c < buf->length - buf->offset - 2; ++c) {
if ((buf->data[c] == 0xff) && (buf->data[c + 1] & 0xe0) &&
(buf->data[c + 1] & 0x1e) == 0x1c) {
/* mpeg v1, layer II header found */
mpa_frame->bit_rate = bit_rates[buf->data[c + 2] >> 4];
mpa_frame->sample_rate = sample_rates[(buf->data[c + 2]
>> 2) & 0x03];
if (mpa_frame->sample_rate < 1)
continue;
mpa_frame->channels = (buf->data[c + 3] >> 6) == 3 ?
1 : 2;
int p = buf->data[c + 2] & 0x01; /* padding bit */
mpa_frame->length = 144 * mpa_frame->bit_rate /
mpa_frame->sample_rate + p;
if (c + mpa_frame->length <= buf->length)
mpa_frame->data = buf->data + c;
break;
}
}
if (c > buf->offset && cPluginAudiorecorder::get_dbg_level() > 0)
cout << "skipped " << c - buf->offset << " byte(s) "
<< description << "> (" << __FILE__ << ", " << __func__
<< "())" << endl;
buf->offset = c;
}
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