Inquiry Regarding RAW Image Processing

[XiaMu799]

I have been studying the MIT-Adobe FiveK Dataset, and I noticed that the dataset provides RAW images in DNG format, which are displayed as color images. However, in Figure 3 of your paper, the Bayer RAW images are shown as grayscale and then converted to demosaiced RAW images using bilinear interpolation.

Could you please clarify the following points regarding your data processing workflow?
How did you handle the conversion of the DNG format RAW images to the grayscale Bayer RAW images?
Was the following line of code used to extract the Bayer RAW image?
raw_img = raw.raw_image_visible
Are there any additional steps or preprocessing techniques applied to the RAW images before using them in your experiments?
I would greatly appreciate any insights or details you can provide about your data preprocessing steps. Thank you for your time and assistance.