setting transparent colors by chosing off the image

Lisa PapLisa Pap Global Mapper UserPosts: 1
edited August 2013 in Raster Data
Hello, I have a satalight image that I need to make parts of if transparent. Is there any way of chosing the color straight off the image or by selecting only portions of it?

Much appreciated,

Lisa
TransGlobe Energy

Comments

  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited January 2012
    Lisa,

    When you point your cursor at the image the RGB color under the cursor should be displayed. Just remember that (or write it down), then when you setup the transparent colors specify that RGB value.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
  • Australian UAVAustralian UAV Global Mapper User Posts: 7
    edited August 2013
    Hi

    I am new to GM and now wish I'd bought it years ago when I started my company. I am using near infrared images (ecw, but I also have them as geotiffs) to locate a certain species of tree that has a distinct colour. In order to find all of these trees in the image I need to know the RGB colour numbers. Mike states above that the colour under the cursor should be displayed. Are you able to tell me where it is displayed and if necessary what tool should I have selected to do this. Or, can you tell me a better way to approach this problem?

    Many thanks for your help.

    Regards
    Heinz
  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited August 2013
    Heinz,

    When you move your cursor over a raster image the color of each pixel (if an image and not a grid layer) should be displayed on the bottom left in the status bar. It will be in the left-side large pane. Are you not seeing that?

    Thanks,

    Mike
    Global Mapper Guru
    gmsupport@bluemarblegeo.com
    Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation
  • Australian UAVAustralian UAV Global Mapper User Posts: 7
    edited August 2013
    Hi Mike

    Thanks for your prompt response. The only thing in the bottom left of my screen is the raster image (ecw) file name. I don't seem to have any other information on the left side of my screen. Is this a toggle on/off feature?

    Heinz

    Heinz,

    When you move your cursor over a raster image the color of each pixel (if an image and not a grid layer) should be displayed on the bottom left in the status bar. It will be in the left-side large pane. Are you not seeing that?

    Thanks,

    Mike
    Global Mapper Guru
    gmsupport@bluemarblegeo.com
    Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation
  • Australian UAVAustralian UAV Global Mapper User Posts: 7
    edited August 2013
    Hi Mike

    I've just changed the image from ecw to geotiff and I now have RGB values showing in the bottom left panel. A trap for young players it seems.

    Many thanks for your help.

    Regards
    Heinz
  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited August 2013
    Heinz,

    Ah actually that feature works for all image layers except ECW, JPEG2000, or MrSID since access can be slow, but I think I can overcome this now. I will let you know when I've got a new build that shows the colors even for ECW.

    Thanks,

    Mike
    Global Mapper Guru
    gmsupport@bluemarblegeo.com
    Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation
  • Australian UAVAustralian UAV Global Mapper User Posts: 7
    edited August 2013
    Thanks Mike. While we are at it can you advise me if this approach is the best way to find specific vegetation based on colour? The aim is to find feral pine trees in native bush and obtain coordinates to give to contractors so they can go directly to them and cut them down. At the moment they walk randomly through the bush looking for them. Not a very efficient or cost effective approach.

    Heinz
  • global_mapperglobal_mapper Administrator Posts: 17,238
    edited August 2013
    I have updated the color display to work for ECW files now. I have placed a new build at http://www.bluemarblegeo.com/downloads/global-mapper/global_mapper14.zip with the latest changes for you to try. Simply download that file and extract the contents into your existing v14.xx installation folder to give it a try. If you are using the 64-bit v14 version there is a new build at http://www.bluemarblegeo.com/downloads/global-mapper/global_mapper14_64bit.zip .

    If you have a particular color profile you are looking for you can right-click on an imagery layer in the Control Center and select to create areas from equal value areas. Then specify the color for the feral pines and specify a "fuzziness" distance large enough to account for color discrepancies. Then you should have areas around possible feral pines so you can more quickly identify them.

    Thanks,

    Mike
    Global Mapper Guru
    gmsupport@bluemarblegeo.com
    Blue Marble Geographics for Coordinate Conversion, Image Reprojection and Vector Translation
  • Australian UAVAustralian UAV Global Mapper User Posts: 7
    edited August 2013
    Excellent! Well done Mike and thanks for making this update for all of us. Thanks also for the advice on colour mapping. This is how I had started to do it. Good to know I was close to the mark.

    Thanks again for your help, we greatly appreciate your efforts.

    Regards
    Heinz
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