public OggTag Read( Stream oggStream )
{
OggTag tag = new OggTag();
byte[] b = new byte[4];
oggStream.Read( b , 0, b .Length);
int vendorstringLength = Utils.GetNumber( b, 0, 3);
b = new byte[vendorstringLength];
oggStream.Read( b , 0, b .Length);
tag.Add("vendor", new string(Encoding.UTF8.GetChars(b)));
b = new byte[4];
oggStream.Read( b , 0, b .Length);
int userComments = Utils.GetNumber( b, 0, 3);
for ( int i = 0; i < userComments; i++ ) {
b = new byte[4];
oggStream.Read( b , 0, b .Length);
int commentLength = Utils.GetNumber( b, 0, 3);
b = new byte[commentLength];
oggStream.Read( b , 0, b .Length);
tag.AddOggField(b);
}
return tag;
}
public OggTag Read(Stream oggStream)
{
OggTag tag = new OggTag();
byte[] b = new byte[4];
oggStream.Read(b, 0, b.Length);
int vendorstringLength = Utils.GetNumber(b, 0, 3);
b = new byte[vendorstringLength];
oggStream.Read(b, 0, b.Length);
tag.Add("vendor", new string(Encoding.UTF8.GetChars(b)));
b = new byte[4];
oggStream.Read(b, 0, b.Length);
int userComments = Utils.GetNumber(b, 0, 3);
for (int i = 0; i < userComments; i++)
{
b = new byte[4];
oggStream.Read(b, 0, b.Length);
int commentLength = Utils.GetNumber(b, 0, 3);
b = new byte[commentLength];
oggStream.Read(b, 0, b.Length);
tag.AddOggField(b);
}
return(tag);
}
public OggTag Read(Stream flacStream)
{
//Begins tag parsing-------------------------------------
if (flacStream.Length == 0)
{
//Empty File
throw new CannotReadException("Error: File empty");
}
flacStream.Seek(0, SeekOrigin.Begin);
//FLAC Header string
byte[] b = new byte[4];
flacStream.Read(b, 0, b.Length);
string flac = new string(System.Text.Encoding.ASCII.GetChars(b));
if (flac != "fLaC")
{
throw new CannotReadException("fLaC Header not found, not a flac file");
}
OggTag tag = null;
//Seems like we hava a valid stream
bool isLastBlock = false;
while (!isLastBlock)
{
b = new byte[4];
flacStream.Read(b, 0, b.Length);
MetadataBlockHeader mbh = new MetadataBlockHeader(b);
switch (mbh.BlockType)
{
//We got a vorbis comment block, parse it
case MetadataBlockHeader.BlockTypes.VorbisComment:
tag = HandleVorbisComment(mbh, flacStream);
mbh = null;
return(tag); //We have it, so no need to go further
//This is not a vorbis comment block, we skip to next block
default:
flacStream.Seek(flacStream.Position + mbh.DataLength, SeekOrigin.Begin);
break;
}
isLastBlock = mbh.IsLastBlock;
mbh = null;
}
//FLAC not found...
throw new CannotReadException("FLAC Tag could not be found or read..");
}
private OggTag HandleVorbisComment(MetadataBlockHeader mbh, Stream flacStream)
{
long oldPos = flacStream.Position;
OggTag tag = oggTagReader.Read(flacStream);
long newPos = flacStream.Position;
if (newPos - oldPos != mbh.DataLength)
{
throw new CannotReadException("Tag length do not match with flac comment data length");
}
return(tag);
}
public void Delete(Stream raf, Stream tempRaf)
{
OggTag tag = null;
try {
tag = (OggTag)reader.Read(raf);
} catch (CannotReadException e) {
Write(new OggTag(), raf, tempRaf);
return;
}
OggTag emptyTag = new OggTag();
if (tag.HasField("vendor"))
{
emptyTag.Set("vendor", tag.Get("vendor")[0] as string);
}
Write(emptyTag, raf, tempRaf);
}
public Tag Read(Stream raf)
{
long oldPos = 0;
//----------------------------------------------------------
//Check wheter we have an ogg stream---------------
raf.Seek(0, SeekOrigin.Begin);
byte[] b = new byte[4];
raf.Read(b, 0, b.Length);
string ogg = new string(System.Text.Encoding.ASCII.GetChars(b));
if (ogg != "OggS")
{
throw new CannotReadException("OggS Header could not be found, not an ogg stream");
}
//--------------------------------------------------
//Parse the tag ------------------------------------
raf.Seek(0, SeekOrigin.Begin);
//Supposing 1st page = codec infos
// 2nd page = comment+decode info
//...Extracting 2nd page
//1st page to get the length
b = new byte[4];
oldPos = raf.Position;
raf.Seek(26, SeekOrigin.Begin);
int pageSegments = raf.ReadByte() & 0xFF; //unsigned
raf.Seek(oldPos, SeekOrigin.Begin);
b = new byte[27 + pageSegments];
raf.Read(b, 0, b.Length);
OggPageHeader pageHeader = new OggPageHeader(b);
raf.Seek(raf.Position + pageHeader.PageLength, SeekOrigin.Begin);
//2nd page extraction
oldPos = raf.Position;
raf.Seek(raf.Position + 26, SeekOrigin.Begin);
pageSegments = raf.ReadByte() & 0xFF; //unsigned
raf.Seek(oldPos, SeekOrigin.Begin);
b = new byte[27 + pageSegments];
raf.Read(b, 0, b.Length);
pageHeader = new OggPageHeader(b);
b = new byte[7];
raf.Read(b, 0, b.Length);
string vorbis = new string(System.Text.Encoding.ASCII.GetChars(b, 1, 6));
if (b[0] != 3 || vorbis != "vorbis")
{
throw new CannotReadException("Cannot find comment block (no vorbis header)");
}
//Begin tag reading
OggTag tag = oggTagReader.Read(raf);
byte isValid = (byte)raf.ReadByte();
if (isValid == 0)
{
throw new CannotReadException("Error: The OGG Stream isn't valid, could not extract the tag");
}
return(tag);
}
