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Loop over images

Member for

1 year 11 months l.thomas


I would like to process individual images from one column sequentially, so basically to loop over the raw of this column, so that I can apply the same processing with openCV/Python (actually to do a matchTemplate)

I though about using the "Table Raw to Variable" node to recover the image as a flow variable in the Python node, but the data type of the generated flow variable seems to be a unicode string that contains the information about the image (like when the renderer is set to multi-line string in the data viewer).

Any suggestion ?

Thanks !



Fri, 10/06/2017 - 12:52

Member for

5 years 3 months


Hi Jindil,

In general you can just use the Chunk Loop Start and Loop End nodes to create a loop to process rows one by one.

I recommend you take a look at the KNIP Python Extension though, they allow you to directly process your images with Python in KNIME.



Fri, 10/06/2017 - 11:41

Member for

1 year 11 months


Hi Gabriel,

Thanks a lot for introducing KNIP ! I will try that ASAP