private void DecodeCompressed(StripData strip)
{
_numBitPerPaletteEntry = strip.CodecId - strip.ParamSubtraction;
_substrationVariable = 1;
_bitStreamManager = new BitStreamManager(strip.ImageData);
_currentLine = 0;
_currentColumn = 0;
bool finishDecode = false;
//if (strip.CodecId >= 0x54 && strip.CodecId <= 0x58) Debugger.Break();
//if (strip.CodecId >= 0x40 && strip.CodecId <= 0x44) Debugger.Break();
//Read palette and Draw the first pixel.
_paletteIndex = _bitStreamManager.ReadByte();
SetCurrentColor();
_resultBitmap.SetPixel(_currentOffset + _currentColumn, _currentLine, _currentColor);
while (!finishDecode)
{
var changeAction = _bitStreamManager.ReadBit();
//changeAction = false (0): Draw next pixel with current palette index.
// Otherwise changeAction is true and we need the next bit to decide what to do.
//changeAction = true (1): We need the next bit to discover what to do.
if (changeAction)
{
if (strip.CompressionType == CompressionTypes.Method1)
{
DecodeCode1Specifics();
}
else if (strip.CompressionType == CompressionTypes.Method2)
{
DecodeCode2Specifics();
}
}
else
{
DrawNextPixel();
}
if ((_currentColumn == 7 && _currentLine == (_height - 1)) || _bitStreamManager.EndOfStream)
{
finishDecode = true;
}
}
UsedIndexes.Sort();
}
private void SetCurrentColor()
{
if (!UsedIndexes.Contains(_paletteIndex))
{
UsedIndexes.Add(_paletteIndex);
}
_currentColor = _pallete.Colors[_paletteIndex];
if ((_paletteIndex == _transparency) && UseTransparentColor)
{
_currentColor = Color.FromArgb(0, _currentColor.R, _currentColor.G, _currentColor.B);
}
}
