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2009.04.28 20:33 "Re: 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;
}