private bool get_side_info()
{
int ch, gr;
if (header.version() == Header.MPEG1)
{
si.main_data_begin = stream.get_bits(9);
if (channels == 1)
si.private_bits = stream.get_bits(5);
else
si.private_bits = stream.get_bits(3);
for (ch = 0; ch < channels; ch++)
{
si.ch[ch].scfsi[0] = stream.get_bits(1);
si.ch[ch].scfsi[1] = stream.get_bits(1);
si.ch[ch].scfsi[2] = stream.get_bits(1);
si.ch[ch].scfsi[3] = stream.get_bits(1);
}
for (gr = 0; gr < 2; gr++)
{
for (ch = 0; ch < channels; ch++)
{
si.ch[ch].gr[gr].part2_3_length = stream.get_bits(12);
si.ch[ch].gr[gr].big_values = stream.get_bits(9);
si.ch[ch].gr[gr].global_gain = stream.get_bits(8);
si.ch[ch].gr[gr].scalefac_compress = stream.get_bits(4);
si.ch[ch].gr[gr].window_switching_flag = stream.get_bits(1);
if ((si.ch[ch].gr[gr].window_switching_flag) != 0)
{
si.ch[ch].gr[gr].block_type = stream.get_bits(2);
si.ch[ch].gr[gr].mixed_block_flag = stream.get_bits(1);
si.ch[ch].gr[gr].table_select[0] = stream.get_bits(5);
si.ch[ch].gr[gr].table_select[1] = stream.get_bits(5);
si.ch[ch].gr[gr].subblock_gain[0] = stream.get_bits(3);
si.ch[ch].gr[gr].subblock_gain[1] = stream.get_bits(3);
si.ch[ch].gr[gr].subblock_gain[2] = stream.get_bits(3);
// Set region_count parameters since they are implicit in this case.
if (si.ch[ch].gr[gr].block_type == 0)
{
// Side info bad: block_type == 0 in split block
return false;
}
else if (si.ch[ch].gr[gr].block_type == 2 && si.ch[ch].gr[gr].mixed_block_flag == 0)
{
si.ch[ch].gr[gr].region0_count = 8;
}
else
{
si.ch[ch].gr[gr].region0_count = 7;
}
si.ch[ch].gr[gr].region1_count = 20 - si.ch[ch].gr[gr].region0_count;
}
else
{
si.ch[ch].gr[gr].table_select[0] = stream.get_bits(5);
si.ch[ch].gr[gr].table_select[1] = stream.get_bits(5);
si.ch[ch].gr[gr].table_select[2] = stream.get_bits(5);
si.ch[ch].gr[gr].region0_count = stream.get_bits(4);
si.ch[ch].gr[gr].region1_count = stream.get_bits(3);
si.ch[ch].gr[gr].block_type = 0;
}
si.ch[ch].gr[gr].preflag = stream.get_bits(1);
si.ch[ch].gr[gr].scalefac_scale = stream.get_bits(1);
si.ch[ch].gr[gr].count1table_select = stream.get_bits(1);
}
}
}
else
{
// MPEG-2 LSF, SZD: MPEG-2.5 LSF
si.main_data_begin = stream.get_bits(8);
if (channels == 1)
si.private_bits = stream.get_bits(1);
else
si.private_bits = stream.get_bits(2);
for (ch = 0; ch < channels; ch++)
{
si.ch[ch].gr[0].part2_3_length = stream.get_bits(12);
si.ch[ch].gr[0].big_values = stream.get_bits(9);
si.ch[ch].gr[0].global_gain = stream.get_bits(8);
si.ch[ch].gr[0].scalefac_compress = stream.get_bits(9);
si.ch[ch].gr[0].window_switching_flag = stream.get_bits(1);
if ((si.ch[ch].gr[0].window_switching_flag) != 0)
{
si.ch[ch].gr[0].block_type = stream.get_bits(2);
si.ch[ch].gr[0].mixed_block_flag = stream.get_bits(1);
si.ch[ch].gr[0].table_select[0] = stream.get_bits(5);
si.ch[ch].gr[0].table_select[1] = stream.get_bits(5);
si.ch[ch].gr[0].subblock_gain[0] = stream.get_bits(3);
si.ch[ch].gr[0].subblock_gain[1] = stream.get_bits(3);
si.ch[ch].gr[0].subblock_gain[2] = stream.get_bits(3);
// Set region_count parameters since they are implicit in this case.
if (si.ch[ch].gr[0].block_type == 0)
{
// Side info bad: block_type == 0 in split block
return false;
}
else if (si.ch[ch].gr[0].block_type == 2 && si.ch[ch].gr[0].mixed_block_flag == 0)
{
si.ch[ch].gr[0].region0_count = 8;
}
else
{
si.ch[ch].gr[0].region0_count = 7;
si.ch[ch].gr[0].region1_count = 20 - si.ch[ch].gr[0].region0_count;
}
}
else
{
si.ch[ch].gr[0].table_select[0] = stream.get_bits(5);
si.ch[ch].gr[0].table_select[1] = stream.get_bits(5);
si.ch[ch].gr[0].table_select[2] = stream.get_bits(5);
si.ch[ch].gr[0].region0_count = stream.get_bits(4);
si.ch[ch].gr[0].region1_count = stream.get_bits(3);
si.ch[ch].gr[0].block_type = 0;
}
si.ch[ch].gr[0].scalefac_scale = stream.get_bits(1);
si.ch[ch].gr[0].count1table_select = stream.get_bits(1);
}
// for(ch=0; ch<channels; ch++)
}
// if (header.version() == MPEG1)
return true;
}
