Legacy ImageMagick Discussions Archive

Hello,

(1) I have a gray-scale geotif file. when I did

" convert t1geo.tif tt.tif "
It failed and the error message is "no decode delegate for this image format"

But It works fine on the version IM.6.2.28. I do not know why.

I need do convert with "clut" option, but the IM.6.6.28 does not have it.

(2) I also want to convert the geotif file to shp file. I know it's not in the option now. Could we do something like this later?

Thank you very much.

Zitian

Type

• identify -list format
  identify -list configure

Is TIFF listed as a supported format? If not, ImageMagick was built without TIFF support. Rebuild from source and include TIFF support and you will then be able to read/write TIFF images.

Thanks.

I does not support tiff.
Could you please tell me which files I should modify in order to get tiff available?

Thanks,

Zitian

Download and install the libTIFF library. Rerun the ImageMagick configure script in the source distribution and make sure to read the last 50 lines of output to ensure TIFF was validated. Now just build and install ImageMagick and you should be able to read/write TIFF images. See http://ftp.imagemagick.org/script/advan ... lation.php .

Now, I got tiff. Thanks!

(1) I did something to convert gray-sclale to color image by means of -clut option. However, It took abour 2.5 min. to finish. My pixel is 6200x3000. Is there any way to increase the speed?

(2) My gray-scale file is geotiff file, afer the convert, is it still a geotiff files?

I used

" convert gray_geo.tif \(gradient_gif -flip \) -clut color_geo.tif

Thanks for the great help.

Zitian

The bad thing about the TIFF standard is that very few people actually follow it. ImageMagick writes TIFF images, not geotif.

Your image converted slowly because it pushed the pixels to/from the pixel cache on disk. You can completely convert the image in memory (which is orders of magnitude faster) by using the Q8 version of ImageMagick or increasing your system memory. But before you do that, type

• identify -list resource

The memory resource lists the maximum amount of memory the pixel cache permits before pushing the pixels to disk. Pixels are also pushed to disk if your system refuses to honor a request for memory. Your image consumes about 3GB of memory for Q16 and assuming the original image and one copy. If you use ImageMagick Q8 only 1.5GB of memory is required.

Thank you again.
After I entey
"identify -list resource"
I got

File Area Memory Map Disk
768 7.9gb 5.93gb 15.82gb 4eb

Anyway, our GIS people need the geogifs.

I did
"convert gray_ges.tif gray.tif

I note that the size of geogif is 18147K and the size of gray.tif is 18170k
The size became bigger. do not know why.

Zitian