Global Mapper v25.0

open Tiff and TFW

gpsguido
gpsguido Global Mapper UserTrusted User
edited October 2009 in Raster Data
I try to open a sample from the kadaster in the netherlands.
It is a TIFF/ TFW file (sample data)

In the file is a TIFF file and .TFW file. It is not possible to get on the screen.

It seems that the data is in RD dutch format.

Comments

  • global_mapper
    global_mapper Administrator
    edited October 2009
    I took a look and found the problem. The image is a 4-channel TIFF file with the 4th channel marked as an alpha (transparency) channel. Every pixel in the alpha channel is marked with a value of 0, or completely transparent, so none of the image data shows through. If I ignore the alpha channel then the image shows fine. You might contact the provider of the data to let them know that their alpha channel has 0 values rather than 255 which is what they likely want.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • gpsguido
    gpsguido Global Mapper User Trusted User
    edited October 2009
    thanks for the quick reply,

    how can I ignore the alpha data. I hope to see something

    guido
  • global_mapper
    global_mapper Administrator
    edited October 2009
    guido,

    There is not currently any way in Global Mapper to ignore the alpha data. You need to contact the data provider and have them correct their data. They likely don't need an alpha channel at all.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • gpsguido
    gpsguido Global Mapper User Trusted User
    edited October 2009
    Can I change it manualy , to see if de data correct is?

    thanks for the help.

    guido
  • global_mapper
    global_mapper Administrator
    edited October 2009
    I think what I'll do is add an option to disable the alpha channel for loaded images. I'll let you know when I have that ready.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • gpsguido
    gpsguido Global Mapper User Trusted User
    edited October 2009
    thanks,

    I'm now testing with the sample data.
  • global_mapper
    global_mapper Administrator
    edited October 2009
    I've added a new option on the Band Setup tab of the Options dialog for layers allowing you to disable the alpha channel. Doing this causes your data to display. I have placed a new build at http://www.globalmapper.com/global_mapper11.zip with the change for you to try. Simply download that file and extract the contents into your existing v11.xx installation folder to give it a try. If you are using the 64-bit version, there is a new build available at http://www.globalmapper.com/global_mapper11_64bit.zip .

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • gpsguido
    gpsguido Global Mapper User Trusted User
    edited October 2009
    sorry,

    Still working with a version 10 globalmapper.

    I will ask if we can upgrade.

    Thanks for changing the programm.

    guido