2009.04.28 18:15 "[Tiff] Libtiff and OpenCV", by Andreas H.

2009.04.28 20:33 "Re: [Tiff] Libtiff and OpenCV", by Andreas H.

> Andreas,
>
> TIFF images are normally (always?) stored with a row of values
> together,
> followed by the next row, etc. So the above would need to have x
> and y
> reversed in handling. Something like:
>

>   TIFFImageData[x + y*w] =  (uint8) img->imageData[h * x + y];

>
> If you get this wrong, your images will be bizzarely skewed. I'm
> assuming
> your interpretation of your source buffer is correct.
>

Thanks for your hint. Unfortunately it doesn't look skewed (in my original version), more like binary with line interleave. I tried to write img (contains a opencv conform imagedata) to a file (using opencv i/o) and it looks fine. Unfortunately it does not support tilling so I converted it as I said with [1] to libtiff style resulting in the buffer TIFFImageData. Changing h*x+y to x+y*w didn't change anything except the image looks more

The image is created this way:

     TIFF* tmptif = TIFFOpen("tmp_foo.tif", "w");
     TIFFSetField(tmptif, TIFFTAG_TILEWIDTH, img->width);
     TIFFSetField(tmptif, TIFFTAG_TILELENGTH, img->height);
     TIFFSetField(tmptif, TIFFTAG_IMAGEWIDTH, img->width);
     TIFFSetField(tmptif, TIFFTAG_IMAGELENGTH, img->height);

For testing I have chosen to write a tile that is actually already the final image. Therefor the imagewidth=tilewidth respectively the imageheight=tileheight.

Best regards,
Andreas

Code from the previous mail:

[1]

IplImage* img;
.
.
.

  TIFFImageData = (uint8*) _TIFFmalloc(width*height * sizeof (uint8));
// allocate temp memory

     for (int x = 0; x < w; x++) {
            // printf("loop...%d to %d\n",count++,w);
            for (int y = 0; y < h; y++) {

                TIFFImageData[h * x + y] =  (uint8) img->imageData[h *

x + y]; // Copy data from ipl to tif
            }

        }

[2]

int WriteTileToTiff(TIFF* tif, uint8* buf, long size, int x, int y){
    if (tif) {
        tsize_t tilenumber = -1;
        tsize_t writtendata = -1;

        writtendata=TIFFWriteTile(tif,buf,x,y,0,NULL);

        printf("%d data written to new tif \n",writtendata);
        if (writtendata==-1){
            printf("[ERROR] TIFFWriteEncodedTile returned -1...\n");
        }

        TIFFClose(tif);
        return 0;
    }else{
        return -1;
    }
  return -1;
}