public static long DPCM(Bitmap input, string param)
{
// Text parameters:
Dictionary <string, string> p = Util.ParseKeyValueList(param);
bool predict = false;
Util.TryParse(p, "predict", ref predict);
int width = input.Width;
int height = input.Height;
if (width < 1 || height < 1)
{
return(0L);
}
// Encoding, only dry-run in memory.
// Backend: adaptive Huffman encoder.
MemoryStream ms = new MemoryStream();
HuffmanCodec huff = new HuffmanCodec();
huff.BinaryStream = ms;
huff.MaxSymbol = 510; // -255 to +255
huff.Open(true);
// Predictive gray-pixel encoding:
int previous = 0;
for (int y = 0; y < height; y++)
{
for (int x = 0; x < width; x++)
{
Color c = input.GetPixel(x, y);
int gr = Draw.RgbToGray(c.R, c.G, c.B);
if (predict)
{
huff.Put(gr - previous + 255);
previous = gr;
}
else
{
huff.Put(gr);
}
}
}
huff.Flush();
long result = ms.Length;
huff.Close();
return(result);
}
public static long PCM(Bitmap input, string param)
{
// Text parameters:
Dictionary <string, string> p = Util.ParseKeyValueList(param);
bool BW = false;
Util.TryParse(p, "bw", ref BW);
int width = input.Width;
int height = input.Height;
if (width < 1 || height < 1)
{
return(0L);
}
// Encoding, only dry-run in memory.
// Backend: adaptive Huffman encoder.
MemoryStream ms = new MemoryStream();
HuffmanCodec huff = new HuffmanCodec();
huff.BinaryStream = ms;
huff.Open(true);
if (BW)
{
int buffer = 0;
int bufLen = 0;
for (int y = 0; y < height; y++)
{
for (int x = 0; x < width; x++)
{
int gr = (input.GetPixel(x, y).GetBrightness() < 0.5f) ? 0 : 1;
buffer += buffer + gr;
if (++bufLen == 8)
{
huff.Put(buffer & 0xff);
buffer = 0;
bufLen = 0;
}
}
// end of scanline
if (bufLen > 0)
{
buffer <<= 8 - bufLen;
huff.Put(buffer & 0xff);
buffer = 0;
bufLen = 0;
}
}
}
else
{
for (int y = 0; y < height; y++)
{
for (int x = 0; x < width; x++)
{
Color c = input.GetPixel(x, y);
int gr = Draw.RgbToGray(c.R, c.G, c.B);
huff.Put(gr);
}
}
}
huff.Flush();
long result = ms.Length;
huff.Close();
return(result);
}