It is not a problem. It is correct information and a fair warning.
Gwyddion works with height fields – or more generally maps of some physical quantity. It is not a graphics software and does not work with colour. Under normal circumstances you open SPM data, not graphics formats (even though Gwyddion can open many of them). It probably does not help that SPM data are commonly called ‘images’…
If you have a colour picture the import module offers several possibilities how to handle it. But what always happens is that the three RGB channels are transformed to a single value (and this value is then false colour mapped to get what you see on screen).
This is perfectly fine if it is what you want. And sometimes you do.
But people try to open all kinds of nonsense. Including pictures of data – exported JPEGs with rulers, screenshots, etc. Then the warning applies. You can use false colour mapping to render data to a colour image. But you cannot magically reverse the process, recreating the data from that image.
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Hi guys, is there someone with the same problem to import images? This error appear for me:
warning: colourful images cannot be reliably mapped to meaningful values
Thank you.
It is not a problem. It is correct information and a fair warning.
Gwyddion works with height fields – or more generally maps of some physical quantity. It is not a graphics software and does not work with colour. Under normal circumstances you open SPM data, not graphics formats (even though Gwyddion can open many of them). It probably does not help that SPM data are commonly called ‘images’…
If you have a colour picture the import module offers several possibilities how to handle it. But what always happens is that the three RGB channels are transformed to a single value (and this value is then false colour mapped to get what you see on screen).
This is perfectly fine if it is what you want. And sometimes you do.
But people try to open all kinds of nonsense. Including pictures of data – exported JPEGs with rulers, screenshots, etc. Then the warning applies. You can use false colour mapping to render data to a colour image. But you cannot magically reverse the process, recreating the data from that image.