VorbisInfoFloor UnpackFloor0(OggBitStream input)
{
var info = new VorbisInfoFloor();
int order = input.ReadBits(8);
int rate = input.ReadBits(16);
int barkmap = input.ReadBits(16);
int ampbits = input.ReadBits(6);
int ampdB = input.ReadBits(8);
int numbooks = input.ReadBits(4) + 1;
if (order < 1 || rate < 1 || barkmap < 1 || numbooks < 1)
{
return(null);
}
for (int j = 0; j < numbooks; ++j)
{
int books = input.ReadByte();
if (books < 0 || books >= CodecSetup.Books)
{
return(null);
}
}
return(info);
}
VorbisInfoFloor UnpackFloor1(OggBitStream input)
{
int max_class = -1;
var info = new VorbisInfoFloor();
// read partitions
int partitions = input.ReadBits(5); // only 0 to 31 legal
var partition_class = new int[partitions];
for (int j = 0; j < partitions; ++j)
{
partition_class[j] = input.ReadBits(4); // only 0 to 15 legal
if (partition_class[j] < 0)
{
return(null);
}
if (max_class < partition_class[j])
{
max_class = partition_class[j];
}
}
// read partition classes
var class_dim = new int[max_class + 1];
for (int j = 0; j < max_class + 1; ++j)
{
class_dim[j] = input.ReadBits(3) + 1; // 1 to 8
int class_subs = input.ReadBits(2); // 0,1,2,3 bits
if (class_subs < 0)
{
return(null);
}
if (class_subs > 0)
{
input.ReadBits(8); // class_book
}
for (int k = 0; k < (1 << class_subs); ++k)
{
int class_subbook = input.ReadBits(8) - 1; // info.class_subbook[j][k]
}
}
// read the post list
int mult = input.ReadBits(2) + 1; // only 1,2,3,4 legal now
int rangebits = input.ReadBits(4);
if (rangebits < 0)
{
return(null);
}
int count = 0;
// var postlist = new int[VorbisInfoFloor.Posit + 2];
for (int j = 0, k = 0; j < partitions; ++j)
{
count += class_dim[partition_class[j]];
if (count > VorbisInfoFloor.Posit)
{
return(null);
}
for (; k < count; ++k)
{
int t = input.ReadBits(rangebits);
if (t < 0 || t >= (1 << rangebits))
{
return(null);
}
// postlist[k+2] = t;
}
}
// postlist[0] = 0;
// postlist[1] = 1<<rangebits;
// don't allow repeated values in post list as they'd result in
// zero-length segments
/*
* var indices = Enumerable.Range (0, count+2).OrderBy (i => postlist[i]).ToArray();
* for (int j = 1; j < count+2; j++)
* if(postlist[indices[j-1]] == postlist[indices[j]])
* return null;
*/
return(info);
}
