public static int[,] LoadPNM(string imgf)
{
var textr = new StreamReader(imgf);
string pnmformat = textr.ReadNextChunkDiscardComments();
if (pnmformat != "P1" && pnmformat != "P2")
throw new Exception("PNM format "+pnmformat+" not supported");
int width = textr.ReadNextChunkDiscardComments().ToInt();
int height = textr.ReadNextChunkDiscardComments().ToInt();
int maxval = 0;
if (pnmformat != "P1")
maxval = textr.ReadNextChunkDiscardComments().ToInt();
//maxval = 255; // ignoring value written in file
if (pnmformat == "P1")
return LoadPBMData(textr, width, height);
else if (pnmformat == "P2")
return LoadPGMData(textr, width, height, maxval);
throw new Exception("PNM format "+pnmformat+" didn't match supported");
}
public static int[,] LoadPGMData(StreamReader textr, int width, int height, int maxval)
{
int[,] data = new int[width, height];
int y = 0;
int x = 0;
while (true) {
string nexts = textr.ReadNextChunkDiscardComments();
if (nexts == null) break;
data[x,y] = nexts.ToInt();
++x;
if (x >= width) {
++y;
x = 0;
}
}
if (y != height || x != 0) {
throw new Exception("specified dimensions not correct, have ("+x.ToString()+","+y.ToString()+") instead of ("+width.ToString()+","+height.ToString()+")");
}
textr.Close();
return data;
}