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);
}
// https://www.xiph.org/vorbis/doc/libvorbis/vorbis_packet_blocksize.html
public int PacketBlockSize(OggPacket op)
{
using (var input = new OggBitStream(op))
{
// Check the packet type
if (input.ReadBits(1) != 0)
{
throw new InvalidDataException("Not an audio data packet.");
}
int modebits = 0;
for (int v = CodecSetup.Modes; v > 1; v >>= 1)
{
modebits++;
}
// read our mode and pre/post windowsize
int mode = input.ReadBits(modebits);
if (-1 == mode)
{
throw new InvalidDataException("Invalid Ogg/Vorbis packet.");
}
return(CodecSetup.BlockSizes[CodecSetup.ModeParam[mode].BlockFlag]);
}
}
// https://xiph.org/vorbis/doc/libvorbis/vorbis_synthesis_headerin.html
public void SynthesisHeaderin(VorbisComment vc, OggPacket op)
{
using (var input = new OggBitStream(op))
{
int packtype = input.ReadUInt8();
var buf = input.ReadBytes(6);
if (!buf.AsciiEqual("vorbis"))
{
throw new InvalidDataException("Not an Ogg/Vorbis stream.");
}
switch (packtype)
{
case 1:
if (!op.BoS)
{
throw InvalidHeader();
}
if (Rate != 0)
{
throw InvalidHeader();
}
UnpackInfo(input);
break;
case 3:
if (0 == Rate)
{
throw InvalidHeader();
}
vc.UnpackComment(input);
break;
case 5:
if (0 == Rate || null == vc.Vendor)
{
throw InvalidHeader();
}
UnpackBooks(input);
break;
default:
throw InvalidHeader();
}
}
}
void UnpackInfo(OggBitStream input)
{
Version = input.ReadInt32();
if (Version != 0)
{
throw new InvalidDataException("Invalid Vorbis encoder version.");
}
Channels = input.ReadUInt8();
Rate = input.ReadInt32();
BitrateUpper = input.ReadInt32();
BitrateNominal = input.ReadInt32();
BitrateLower = input.ReadInt32();
CodecSetup.BlockSizes[0] = 1 << input.ReadBits(4);
CodecSetup.BlockSizes[1] = 1 << input.ReadBits(4);
if (input.ReadBits(1) != 1)
{
throw InvalidHeader();
}
}
internal void UnpackComment(OggBitStream input)
{
int vendor_len = input.ReadInt32();
if (vendor_len < 0)
{
throw VorbisInfo.InvalidHeader();
}
var vendor = input.ReadBytes(vendor_len);
int count = input.ReadInt32();
if (count < 0)
{
throw VorbisInfo.InvalidHeader();
}
var comments = new List <byte[]> (count);
for (int i = 0; i < count; ++i)
{
int len = input.ReadInt32();
if (len < 0)
{
throw VorbisInfo.InvalidHeader();
}
var bytes = input.ReadBytes(len);
comments.Add(bytes);
}
if (input.ReadBits(1) != 1)
{
throw VorbisInfo.InvalidHeader();
}
this.Vendor = vendor;
this.Comments = comments;
}
VorbisInfoMapping UnpackMapping(OggBitStream input)
{
var info = new VorbisInfoMapping();
int b = input.ReadBits(1);
if (b < 0)
{
return(null);
}
if (b > 0)
{
info.submaps = input.ReadBits(4) + 1;
if (info.submaps <= 0)
{
return(null);
}
}
else
{
info.submaps = 1;
}
b = input.ReadBits(1);
if (b < 0)
{
return(null);
}
if (b > 0)
{
info.coupling_steps = input.ReadBits(8) + 1;
if (info.coupling_steps <= 0)
{
return(null);
}
for (int i = 0; i < info.coupling_steps; ++i)
{
int bits = CountBits((uint)Channels);
int testM = input.ReadBits(bits);
int testA = input.ReadBits(bits);
if (testM < 0 || testA < 0 || testM == testA ||
testM >= Channels || testA >= Channels)
{
return(null);
}
}
}
if (input.ReadBits(2) != 0)
{
return(null);
}
if (info.submaps > 1)
{
for (int i = 0; i < Channels; ++i)
{
int chmuxlist = input.ReadBits(4);
if (chmuxlist >= info.submaps || chmuxlist < 0)
{
return(null);
}
}
}
for (int i = 0; i < info.submaps; ++i)
{
input.ReadByte(); // time submap unused
int floorsubmap = input.ReadByte();
if (floorsubmap >= CodecSetup.Floors || floorsubmap < 0)
{
return(null);
}
int residuesubmap = input.ReadByte();
if (residuesubmap >= CodecSetup.Residues || residuesubmap < 0)
{
return(null);
}
}
return(info);
}
object UnpackResidue(OggBitStream input)
{
var info = new VorbisInfoResidue();
info.begin = input.ReadBits(24);
info.end = input.ReadBits(24);
info.grouping = input.ReadBits(24) + 1;
info.partitions = input.ReadBits(6) + 1;
info.groupbook = input.ReadBits(8);
// check for premature EOP
if (info.groupbook < 0)
{
return(null);
}
int acc = 0;
for (int j = 0; j < info.partitions; ++j)
{
int cascade = input.ReadBits(3);
int cflag = input.ReadBits(1);
if (cflag < 0)
{
return(null);
}
if (cflag > 0)
{
int c = input.ReadBits(5);
if (c < 0)
{
return(null);
}
cascade |= c << 3;
}
// info.secondstages[j] = cascade;
acc += CountSetBits((uint)cascade);
}
for (int j = 0; j < acc; ++j)
{
int book = input.ReadBits(8);
if (book < 0)
{
return(null);
}
if (book >= CodecSetup.Books)
{
return(null);
}
// if (CodecSetup.book_param[book].maptype == 0) return null;
// info.booklist[j] = book;
}
if (info.groupbook >= CodecSetup.Books)
{
return(null);
}
/*
* int entries = CodecSetup.book_param[info.groupbook].entries;
* int dim = CodecSetup.book_param[info.groupbook].dim;
* int partvals = 1;
* if (dim < 1)
* return null;
* while (dim > 0)
* {
* partvals *= info.partitions;
* if (partvals > entries)
* return null;
* dim--;
* }
* info.partvals = partvals;
*/
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);
}
StaticCodebook StaticBookUnpack(OggBitStream input)
{
// make sure alignment is correct
if (input.ReadBits(24) != 0x564342)
{
return(null);
}
var s = new StaticCodebook();
// first the basic parameters
s.dim = input.ReadBits(16);
s.entries = input.ReadBits(24);
if (-1 == s.entries)
{
return(null);
}
if (iLog((uint)s.dim) + iLog((uint)s.entries) > 24)
{
return(null);
}
// codeword ordering.... length ordered or unordered?
switch (input.ReadBits(1))
{
case 0:
// allocated but unused entries?
int unused = input.ReadBits(1);
// unordered
s.lengthlist = new byte[s.entries];
// allocated but unused entries?
if (unused > 0)
{
// yes, unused entries
for (int i = 0; i < s.entries; ++i)
{
if (input.ReadBits(1) > 0)
{
int num = input.ReadBits(5);
if (-1 == num)
{
return(null);
}
s.lengthlist[i] = (byte)(num + 1);
}
else
{
s.lengthlist[i] = 0;
}
}
}
else
{
// all entries used; no tagging
for (int i = 0; i < s.entries; ++i)
{
int num = input.ReadBits(5);
if (-1 == num)
{
return(null);
}
s.lengthlist[i] = (byte)(num + 1);
}
}
break;
case 1: // ordered
int length = input.ReadBits(5) + 1;
if (0 == length)
{
return(null);
}
s.lengthlist = new byte[s.entries];
for (int i = 0; i < s.entries;)
{
int num = input.ReadBits(iLog((uint)(s.entries - i)));
if (-1 == num || length > 32 || num > s.entries - i ||
(num > 0 && ((num - 1) >> (length - 1)) > 1))
{
return(null);
}
for (int j = 0; j < num; ++j, ++i)
{
s.lengthlist[i] = (byte)length;
}
length++;
}
break;
default:
return(null);
}
// Do we have a mapping to unpack?
switch ((s.maptype = input.ReadBits(4)))
{
case 0: // no mapping
break;
case 1:
case 2:
// implicitly populated value mapping
// explicitly populated value mapping
s.q_min = input.ReadInt32();
s.q_delta = input.ReadInt32();
s.q_quant = input.ReadBits(4) + 1;
s.q_sequencep = input.ReadBits(1);
if (-1 == s.q_sequencep)
{
return(null);
}
int quantvals = 0;
switch (s.maptype)
{
case 1:
quantvals = s.dim == 0 ? 0 : s.Maptype1Quantvals();
break;
case 2:
quantvals = s.entries * s.dim;
break;
}
// quantized values
s.quantlist = new int[quantvals];
for (int i = 0; i < quantvals; ++i)
{
s.quantlist[i] = input.ReadBits(s.q_quant);
}
if (quantvals > 0 && s.quantlist[quantvals - 1] == -1)
{
return(null);
}
break;
default: // EOF
return(null);
}
// all set
return(s);
}
void UnpackBooks(OggBitStream input)
{
// codebooks
CodecSetup.Books = input.ReadUInt8() + 1;
if (CodecSetup.Books <= 0)
{
throw InvalidHeader();
}
for (int i = 0; i < CodecSetup.Books; ++i)
{
var param = StaticBookUnpack(input);
if (null == param)
{
throw InvalidHeader();
}
CodecSetup.BookParam[i] = param;
}
// time backend settings; hooks are unused
int times = input.ReadBits(6) + 1;
if (times <= 0)
{
throw InvalidHeader();
}
for (int i = 0; i < times; ++i)
{
int test = input.ReadBits(16);
if (test < 0 || test >= TimeB)
{
throw InvalidHeader();
}
}
// floor backend settings
CodecSetup.Floors = input.ReadBits(6) + 1;
if (CodecSetup.Floors <= 0)
{
throw InvalidHeader();
}
for (int i = 0; i < CodecSetup.Floors; i++)
{
int floor_type = input.ReadBits(16);
if (floor_type < 0 || floor_type >= FloorB)
{
throw InvalidHeader();
}
CodecSetup.FloorType[i] = floor_type;
var param = FloorMethods[floor_type] (input);
if (null == param)
{
throw InvalidHeader();
}
CodecSetup.FloorParam[i] = param;
}
// residue backend settings
CodecSetup.Residues = input.ReadBits(6) + 1;
if (CodecSetup.Residues <= 0)
{
throw InvalidHeader();
}
for (int i = 0; i < CodecSetup.Residues; ++i)
{
int residue_type = input.ReadBits(16);
if (residue_type < 0 || residue_type >= ResB)
{
throw InvalidHeader();
}
CodecSetup.ResidueType[i] = residue_type;
var param = UnpackResidue(input);
if (null == param)
{
throw InvalidHeader();
}
CodecSetup.ResidueParam[i] = param;
}
// map backend settings
CodecSetup.Maps = input.ReadBits(6) + 1;
if (CodecSetup.Maps <= 0)
{
throw InvalidHeader();
}
for (int i = 0; i < CodecSetup.Maps; ++i)
{
int map_type = input.ReadBits(16);
if (map_type < 0 || map_type >= MapB)
{
throw InvalidHeader();
}
CodecSetup.MapType[i] = map_type;
var param = UnpackMapping(input);
if (null == param)
{
throw InvalidHeader();
}
CodecSetup.MapParam[i] = param;
}
// mode settings
CodecSetup.Modes = input.ReadBits(6) + 1;
if (CodecSetup.Modes <= 0)
{
throw InvalidHeader();
}
for (int i = 0; i < CodecSetup.Modes; ++i)
{
CodecSetup.ModeParam[i].BlockFlag = input.ReadBits(1);
CodecSetup.ModeParam[i].WindowType = input.ReadBits(16);
CodecSetup.ModeParam[i].TransformType = input.ReadBits(16);
CodecSetup.ModeParam[i].Mapping = input.ReadBits(8);
if (CodecSetup.ModeParam[i].WindowType >= WindowB ||
CodecSetup.ModeParam[i].TransformType >= WindowB ||
CodecSetup.ModeParam[i].Mapping >= CodecSetup.Maps ||
CodecSetup.ModeParam[i].Mapping < 0)
{
throw InvalidHeader();
}
}
if (input.ReadBits(1) != 1)
{
throw InvalidHeader();
}
}