Input raster for Textural features?

OTB Usage
1

Hi,

I want to perform HaralickTextures and SFSTextures to improve a classification.
My input image is a RGB raster.
It’s not clear in the documentation, but my input image for theses textures calculations need to be a greyscale raster (created in an other treatment) or directly my rgb image ?

Thanks in advance

2

Hi Antoine,

Thank you for your interest in Orfeo ToolBox.
All these applications compute textures on a grayscale image and take a “input_channel” parameter (by default, 1). If you use a RGB raster an omit the parameter, it will select red band.
You can also compute a single band image (for instance, a radiometric index from your input RGB raster) and give it as input of the SFS/Haralick/Pantex/…Texture application !

Hope that helps, best regards

Yannick

4

Hi Yannick,

Ok thx, so all textural treatments in Features Extractions section must take a greyscale image with 1 band.
In RadiometricIndices function, the BI Index (Brightness) corresponds to a Grayscale index ? (no?)

5

Hi Antoine,

Yes, these texture extraction applications will consider a single band image : if a multi-band image is given as input, only the first channel will be treated.
And you’re right, a brightness index is a single band image (that you can display in a gray scale or any other way in your favorite tool).

Yannick

6

Hi Yannick,

Ok thx for your repsonse !