AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

2006.08.03 19:58 "[Tiff] libTiff and MSVC 6.0", by Sean Burke
2006.08.03 21:38 "RE: [Tiff] libTiff and MSVC 6.0", by
2006.08.04 14:32 "Re: [Tiff] libTiff and MSVC 6.0", by Gerben Vos
2006.08.04 15:00 "RE: [Tiff] libTiff and MSVC 6.0", by

2006.08.04 15:00 "RE: [Tiff] libTiff and MSVC 6.0", by

Sean wrote:

__declspec(dllexport) write2DTIFF(char *fname,
                                unsigned long *buf,

    tif = TIFFOpen(fname, "w");
    TIFFSetField(tif, TIFFTAG_IMAGEWIDTH, width);
    TIFFSetField(tif, TIFFTAG_IMAGELENGTH, height);
    TIFFSetField(tif, TIFFTAG_COMPRESSION, COMPRESSION_LZW);
    TIFFSetField(tif, TIFFTAG_BITSPERSAMPLE, 16);

Okay, some more things have occurred to me. Two potential problems:

  1. BitsPerSample is set to 16, while the allowed values (for greyscale) are 4 and 8.
  2. "unsigned long *buf" points to 32-bit values, which differ from the BitsPerSample size (16-bit samples).

Try using a value of 8 for BitsPerSample, change "unsigned long *buf" to "unsigned char * buf", copy your original data into a temporary buffer, which contains the original samples each divided by 256 (or bit-shifted right by 8), and pass that temporary buffer.

    TIFFSetField(tif, TIFFTAG_SAMPLESPERPIXEL, 1);
    TIFFSetField(tif, TIFFTAG_PLANARCONFIG, PLANARCONFIG_CONTIG);
    if((TIFFWriteEncodedStrip(tif, 0, buf, width*height)) == -1){
        fprintf(stderr, "TIFFWriteEncodedStrip failed.\n");
    }
    TIFFClose(tif);