1
0
mirror of https://github.com/rofafor/vdr-plugin-femon.git synced 2023-10-10 13:36:53 +02:00
vdr-plugin-femon/femonaac.c

106 lines
2.9 KiB
C
Raw Normal View History

/*
* Frontend Status Monitor plugin for the Video Disk Recorder
*
* See the README file for copyright information and how to reach the author.
*
*/
#include "femontools.h"
#include "femonaac.h"
#define IS_HEAAC_AUDIO(buf) (((buf)[0] == 0xFF) && (((buf)[1] & 0xF6) == 0xF0))
2015-03-07 17:22:02 +01:00
int cFemonAAC::sampleRateS[16] =
{
96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050, 16000, 12000, 11025, 8000, -1, -1, -1, -1
};
2015-03-07 17:22:02 +01:00
cFemonAAC::cFemonAAC(cFemonAudioIf *audioHandlerP)
: audioHandlerM(audioHandlerP)
{
2009-08-25 19:22:06 +02:00
}
cFemonAAC::~cFemonAAC()
{
}
2015-03-07 17:22:02 +01:00
bool cFemonAAC::processAudio(const uint8_t *bufP, int lenP)
2009-08-25 19:22:06 +02:00
{
2015-03-07 17:22:02 +01:00
cFemonBitStream bs(bufP, lenP * 8);
2009-08-25 19:22:06 +02:00
2015-03-07 17:22:02 +01:00
if (!audioHandlerM)
return false;
/* ADTS Fixed Header:
* syncword 12b always: '111111111111'
* id 1b 0: MPEG-4, 1: MPEG-2
* layer 2b always: '00'
* protection_absent 1b
* profile 2b 0: Main profile AAC MAIN 1: Low Complexity profile (LC) AAC LC 2: Scalable Sample Rate profile (SSR) AAC SSR 3: (reserved) AAC LTP
* sampling_frequency_index 4b
* private_bit 1b
* channel_configuration 3b
* original/copy 1b
* home 1b
* emphasis 2b only if ID == 0 (ie MPEG-4)
*/
2009-08-25 19:22:06 +02:00
// skip PES header
2015-03-07 17:22:02 +01:00
if (!PesLongEnough(lenP))
2009-08-25 19:22:06 +02:00
return false;
2015-03-07 17:22:02 +01:00
bs.SkipBits(8 * PesPayloadOffset(bufP));
2009-08-25 19:22:06 +02:00
// HE-AAC audio detection
2011-11-19 15:02:16 +01:00
if (bs.GetBits(12) != 0xFFF) // syncword
2009-08-25 19:22:06 +02:00
return false;
2011-11-19 15:02:16 +01:00
bs.SkipBit(); // id
2009-08-25 19:22:06 +02:00
// layer must be 0
2011-11-19 15:02:16 +01:00
if (bs.GetBits(2)) // layer
2009-08-25 19:22:06 +02:00
return false;
2011-11-19 15:02:16 +01:00
bs.SkipBit(); // protection_absent
bs.SkipBits(2); // profile
int sampling_frequency_index = bs.GetBits(4); // sampling_frequency_index
bs.SkipBit(); // private pid
int channel_configuration = bs.GetBits(3); // channel_configuration
2015-03-07 17:22:02 +01:00
audioHandlerM->SetAudioCodec(AUDIO_CODEC_HEAAC);
audioHandlerM->SetAudioBitrate(AUDIO_BITRATE_RESERVED);
switch (channel_configuration) {
case 0:
2015-03-07 17:22:02 +01:00
audioHandlerM->SetAudioChannel(AUDIO_CHANNEL_MODE_STEREO);
break;
case 1:
2015-03-07 17:22:02 +01:00
audioHandlerM->SetAudioChannel(AUDIO_CHANNEL_MODE_JOINT_STEREO);
break;
case 2:
2015-03-07 17:22:02 +01:00
audioHandlerM->SetAudioChannel(AUDIO_CHANNEL_MODE_DUAL);
break;
case 3:
2015-03-07 17:22:02 +01:00
audioHandlerM->SetAudioChannel(AUDIO_CHANNEL_MODE_SINGLE);
break;
default:
2015-03-07 17:22:02 +01:00
audioHandlerM->SetAudioChannel(AUDIO_CHANNEL_MODE_INVALID);
break;
}
switch (sampling_frequency_index) {
case 0xC ... 0xF:
2015-03-07 17:22:02 +01:00
audioHandlerM->SetAudioSamplingFrequency(AUDIO_SAMPLING_FREQUENCY_RESERVED);
break;
default:
2015-03-07 17:22:02 +01:00
audioHandlerM->SetAudioSamplingFrequency(sampleRateS[sampling_frequency_index]);
break;
}
return true;
}