CreatePixelBlock fails in loop

RohitPatil — Wed, 05 May 2010 22:34:19 GMT

I am trying calculate values and update a large raster (11021 * 10643) of type Int32. Since I get an error ("the input string is not a geographic or projected coordinate system") if i try to read the whole raster, I am doing this by splitting the raster into 4 parts and performing calculations. The first iteration runs fine and the output raster is correctly updated, however in the second iteration error occurs on the last line of the following code where it creates a pixelblock3 on output raster(other rasters which are of the same size as the output do not get this error). Am i doing something wrong?

Is it better to read the raster lengthwise (few rows at a time)?

 for (int block = 0; block < 4; block++)
                {
                    int shire = 13;
                    
                    DblPnt blockStart = new DblPnt();
                    DblPnt blockExtent = new DblPnt();
                    blockExtent.SetCoords(pEUCProps.Width / 2, pEUCProps.Height / 2); 

// 5510* 5321 is the extent of block which corresponds to 1/4 of the cells in complete raster. 
// If i reduce the extent to 5500 * 5300 I still get error while creating pixelblock of output in 
//second iteration

                    switch (block)
                    {
                        case 0:
                            blockStart.SetCoords(0, 0);
                            break;
                        case 1:
                            blockStart.SetCoords(0, pEUCProps.Height / 2);
                            break;

                        case 2:
                            blockStart.SetCoords(pEUCProps.Width / 2, 0);
                            break;

                        case 3:
                            blockStart.SetCoords(pEUCProps.Width / 2, pEUCProps.Height / 2);
                            break;
                    }

                    IPixelBlock pEUCBlock = pEUCRawPixels.CreatePixelBlock(blockExtent);
                    pEUCRawPixels.Read(blockStart, pEUCBlock);

                    IPixelBlock pZonesBlock = pZonesRawPixels.CreatePixelBlock(blockExtent);
                    pZonesRawPixels.Read(blockStart, pZonesBlock);

                    IPixelBlock pBuildableBlock = pBuildableRawPixels.CreatePixelBlock(blockExtent);
                    pBuildableRawPixels.Read(blockStart, pBuildableBlock);

                    IPixelBlock3 pOutBlock = (IPixelBlock3)pOutRawPixels.CreatePixelBlock(blockExtent);

Re: CreatePixelBlock fails in loop

RohitPatil — Thu, 06 May 2010 17:16:15 GMT

i changed the pixel block size to 1/16 of complete raster and the loop worked...

topic CreatePixelBlock fails in loop in ArcObjects SDK Questions

CreatePixelBlock fails in loop

Re: CreatePixelBlock fails in loop