I'm going to use the following dataset to do semantic segmentation with U-Net network.
This dataset contains brain MR images together with manual FLAIR abnormality segmentation masks. The images were obtained from The Cancer Imaging Archive (TCIA). They correspond to 110 patients included in The Cancer Genome Atlas (TCGA) lower-grade glioma collection with at least fluid-attenuated inversion recovery (FLAIR) sequence and genomic cluster data available. Tumor genomic clusters and patient data is provided in data.csv file.
I have found that brain images are in TIFF format, and they are in RGB (with three channels). I have opened one with Gimp:
I don't know if there is any special information on each colour channel because this question is strange (I don't understand it).
Which channel do I have to use if I want to use greyscale images? Or maybe I can convert them into greyscale.