2008.02.11 07:43 "[Tiff] TIFFReadRGBAImage rendering upside-down", by Mick O'Neill

2008.02.11 16:03 "Re: [Tiff] TIFFReadRGBAImage rendering upside-down", by Frank Warmerdam

I have some odd TIFF files here (that do have a subsampling error being reported for the OJPEG compressed images) that, when I call the TIFFReadRGBAImage function, renders the RGBA upside down (flipped, not rotated). I was wondering if there was something in the TIFF headers that tell me this is happening? Or perhaps some other info elsewhere. There are some applications around that read these TIFFs correctly, and others that will not read them at all.

libtiff version 3.9.0 Beta

Any ideas appreciated.


The tiffinfo reports:

    Orientation: row 0 top, col 0 lhs

Which is (I believe) the default case where the first pixel in the file is the top left corner of the image. I also ran tiff2rgba with the current development version of libtiff and tiff2rgba and it came out with the first page "right side up", so I'm surprised you are having problems.

Best regards,

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