2004.01.23 04:48 "[Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Pushkar Pradhan

2004.01.23 15:18 "Re: [Tiff] How to convert MINISBLACK to PHOTOMETRIC_RGB", by Bob Friesenhahn

When I create a subset image (to take only 3 bands out of 6) IMAGINE software creates a MINISBLACK TIF file (there seems to be no option to change this). This is what tiffinfo reports:

  Bits/Sample: 8
  Sample Format: unsigned integer
  Compression Scheme: None
  Photometric Interpretation: min-is-black
  Extra Samples: 2<unspecified, unspecified>
  Orientation: row 0 top, col 0 lhs
  Samples/Pixel: 3

Now I want to read this file in MATLAB whose TIFF reader is limited to reading RGB and PALETTED images (that too only 8-bit and 16-bit). Thus it only reads the 1st band of this file.

I saw there is utility pal2rgb but is there something similar to min-is-black images to RGB interpretation?

You can rewrite such files using GDAL software. I have implemented Photometric setting as an option to the TIFF driver per your recent request. You can try to do something like:

$ gdal_translate -of GTiff -co "PHOTOMETRIC=RGB" bad.tif good.tif

How does this treat the two extra samples? Does it ignore them?

If only the normal gray channel is needed but expressed as RGB, you can do the same in GraphicsMagick (or ImageMagick):

  gm convert -type TrueColor bad.tif good.tif


Bob Friesenhahn