public bool Init(IStorageFile stream, bool readTags, string stateJson = null)
{
if (stream == null)
{
throw new ArgumentNullException($"Null argument {nameof(stream)} !");
}
_readTags = readTags;
_fileStream = stream;
bsbuf = bsspace_1;
_fileStream.UseReadBuffer(2048);
bool stateIsRestored = false;
if (!string.IsNullOrEmpty(stateJson))
{
var state = JsonConvert.DeserializeObject <Mp3EncoderState>(stateJson);
if (state != null)
{
Args = state.Args;
bsnum = state.bsnum;
firsthead = state.firsthead;
fr = state.frame;
framesize = state.framesize;
fsize = state.fsize;
fsizeold = state.fsizeold;
oldhead = state.oldhead;
ssize = state.ssize;
syncword = state.syncword;
_frameOffsets = (state.Args.FramesFileOffsets?.ToList() ?? null);
// Restore full offset instead of relative offset value.
if (_frameOffsets != null)
{
for (int i = 1; i < _frameOffsets.Count; i++)
{
_frameOffsets[i] += _frameOffsets[i - 1];
}
}
// Seek to the beggining of the current frame.
_fileStream.Seek(state.FileOffset, SeekOrigin.Begin);
// Read current frame data.
//ReadFrame();
stateIsRestored = true;
}
}
if (!stateIsRestored)
{
ReadFrame();
}
return(true);
}
public bool ReadTags(IStorageFile file, int headerDataSize)
{
//TALB - album
//TCOM - composer
//TIT2 - song name.
//TYER - year
//TCON - genre
//TRCK - track number
//TPE1 - lead performer
//TPE2 - band
//APIC - Attached picture
HashSet <string> setFrameIds = new HashSet <string>(new[] { "TALB", "TCOM", "TIT2", "TYER", "TCON", "TRCK", "TPE1", "TPE2", "APIC" });
Dictionary <string, string> dicAttributes = new Dictionary <string, string>();
List <AttachedPicture> attachedPictures = new List <AttachedPicture>();
int offset = 0, offsetEnd = 0, numread = 0;
byte[] tbuf = new byte[10];
while (offset <= headerDataSize)
{
// Read frame id(4 bytes), size(4 bytes) and flags (2 bytes).
numread = file.Read(tbuf, 0, 10);
if (numread != 10)
{
return(false);
}
var attrName = ReadAsString(tbuf, 0, 4, out offsetEnd);
if (string.IsNullOrEmpty(attrName))
{
break;
}
int size = (int)(BigEndianRead(tbuf, 4) & 0x7FFFFFFF);
if (size == 0)
{
break;
}
offset += (10 + size);
if (setFrameIds.Contains(attrName))
{
if (attrName == "APIC") // Attached picture.
{
var pict = ReadAttachedPicture(file, size);
if (pict != null)
{
attachedPictures.Add(pict);
}
else
{
break;
}
// _fileStream.Seek(size, SeekOrigin.Current); // Next attribute.
}
else
{
byte[] frameData = new byte[size];
numread = file.Read(frameData, 0, size);
if (numread != size)
{
return(false);
}
dicAttributes[attrName] = ReadAsString(frameData, 1, size - 1, out offsetEnd, frameData[0]);
}
}
else
{
file.Seek(size, SeekOrigin.Current); // Next attribute.
}
}
_attachedPictures = attachedPictures; // Attached pictures.
_id3v2Tags = dicAttributes; // Set ID3v2 attributes.
return(true);
}
public bool Seek_StreamByPos(long pos /*packet position*/, bool readFrame = true)
{
long Posi = pos;
long OldPosi, XPosi;
if (Posi >= 0 && Posi <= MaxFrames)
{
if (((long)Args.CurrentPos) != pos) // Check current position.
{
OldPosi = _fileStream.Seek(0, SeekOrigin.Current);
if (this._frameOffsets != null && this._frameOffsets.Count > pos)
{
XPosi = this._frameOffsets[(int)pos];
}
else
{
if (Args.IsVBR)
{
int index = (int)((pos * 100.0) / Args.NumFrames);
XPosi = (long)(((Args.TOC[index] * 1.0) / 256.0) * Args.FileLength) + Args.FirstFrameOffset;
}
else
{
XPosi = ((Framesize + 4) * Posi) + Args.FirstFrameOffset;
}
}
try
{
_fileStream.Seek(XPosi, SeekOrigin.Begin);
}
catch (IOException)
{
_fileStream.Seek(OldPosi, SeekOrigin.Begin);
return(false);
}
Args.CurrentPos = (ulong)Posi;
}
if (readFrame)
{
int Res;
read_again:
Res = ReadFrame();
if (Res != 0)
{
Args.CurrentPos++;
}
if (Res == 0 && Res != -2)
{
goto read_again;
}
}
else
{
framebuffIsEmpty = true; // Read frame of current packet.
}
return(true);
}
return(false);
}
