Initial community commit
This commit is contained in:
parent
537bcbc862
commit
fc06254474
16440 changed files with 4239995 additions and 2 deletions
110
Src/aacdec/ADTSHeader.c
Normal file
110
Src/aacdec/ADTSHeader.c
Normal file
|
@ -0,0 +1,110 @@
|
|||
#include "ADTSHeader.h"
|
||||
#include <bfc/error.h>
|
||||
|
||||
enum
|
||||
{
|
||||
ADTS_NOT_PROTECTED=1,
|
||||
ADTS_PROTECTED=0,
|
||||
ADTS_SYNC = 0xFFF,
|
||||
ADTS_MAIN = 0x00,
|
||||
ADTS_LC = 0x01,
|
||||
ADTS_SSR = 0x10,
|
||||
ADTS_LTP = 0x11,
|
||||
};
|
||||
|
||||
|
||||
int nsaac_adts_parse(nsaac_adts_header_t header, const uint8_t *buffer)
|
||||
{
|
||||
unsigned int syncword = (buffer[0] << 4) | (buffer[1] >> 4);
|
||||
unsigned int layer;
|
||||
unsigned int sample_rate_index;
|
||||
if (syncword != ADTS_SYNC)
|
||||
return NErr_LostSynchronization;
|
||||
|
||||
header->syncword = syncword;
|
||||
header->id = (buffer[1] >> 3) & 1;
|
||||
layer = (buffer[1] >> 1) & 3;
|
||||
if (layer != 0)
|
||||
return NErr_WrongFormat;
|
||||
header->layer = layer;
|
||||
header->protection = (buffer[1]) & 1;
|
||||
header->profile = (buffer[2] >> 6) & 3;
|
||||
sample_rate_index = (buffer[2] >> 2) & 0xF;
|
||||
if (sample_rate_index == 15)
|
||||
return NErr_UnsupportedFormat; // might actually be OK if we can separately signal the sample rate
|
||||
|
||||
if (sample_rate_index > 13)
|
||||
return NErr_Reserved;
|
||||
|
||||
header->sample_rate_index = sample_rate_index;
|
||||
header->private_bit = (buffer[2] >> 1) & 1;
|
||||
header->channel_configuration = ((buffer[2] & 1) << 2) | ((buffer[3] >> 6) & 3);
|
||||
header->original = (buffer[3] >> 5) &1;
|
||||
header->home = (buffer[3] >> 4) &1;
|
||||
|
||||
//copyright_identification_bit = (buffer[3] >> 3) & 1;
|
||||
//copyright_identification_start = (buffer[3] >> 2) & 1;
|
||||
header->frame_length = ((buffer[3] & 3) << 11) | (buffer[4]<<3) | ((buffer[5] >> 5) & 7);
|
||||
header->buffer_fullness = ((buffer[5] & 0x1F) << 6) | (buffer[6] >> 2);
|
||||
header->num_data_blocks = buffer[6] & 3;
|
||||
return NErr_Success;
|
||||
}
|
||||
|
||||
|
||||
static const unsigned int aac_sratetab[] =
|
||||
{
|
||||
96000,
|
||||
88200,
|
||||
64000,
|
||||
48000,
|
||||
44100,
|
||||
32000,
|
||||
24000,
|
||||
22050,
|
||||
16000,
|
||||
12000,
|
||||
11025,
|
||||
8000,
|
||||
7350,
|
||||
};
|
||||
|
||||
unsigned int nsaac_adts_get_samplerate(nsaac_adts_header_t header)
|
||||
{
|
||||
return aac_sratetab[header->sample_rate_index];
|
||||
}
|
||||
|
||||
int nsaac_adts_match(nsaac_adts_header_t header1, nsaac_adts_header_t header2)
|
||||
{
|
||||
if (header1->id != header2->id)
|
||||
return NErr_False;
|
||||
|
||||
if (header1->profile != header2->profile)
|
||||
return NErr_False;
|
||||
|
||||
if (header1->sample_rate_index != header2->sample_rate_index)
|
||||
return NErr_False;
|
||||
|
||||
if (header1->channel_configuration != header2->channel_configuration)
|
||||
return NErr_False;
|
||||
|
||||
return NErr_True;
|
||||
}
|
||||
|
||||
int nsaac_adts_get_channel_count(nsaac_adts_header_t header)
|
||||
{
|
||||
switch(header->channel_configuration)
|
||||
{
|
||||
case 7:
|
||||
return 8;
|
||||
default:
|
||||
return header->channel_configuration;
|
||||
}
|
||||
}
|
||||
|
||||
size_t nsaac_adts_get_header_size(nsaac_adts_header_t header)
|
||||
{
|
||||
if (header->protection == ADTS_PROTECTED)
|
||||
return 9;
|
||||
else
|
||||
return 7;
|
||||
}
|
Loading…
Add table
Add a link
Reference in a new issue