Data Resolution Clarification

Hello,

We would like to confirm the structure of the .tif case file, specifically this statement: "Each case is a WSI of prostatectomy containing cancer in the form of pyramidal TIF, which is a multi-resolution, tiled format. Each resolution is stored as a separate level within the TIF. The first level contains the image at full resolution. Each subsequent level is the previous level, downsampled by a factor of four. "

We want to confirm if this means that all the levels in the .tif image are the same image at the same magnification/zoom but with different resolutions only. We tried observing them for a sample case and obtained this result, and we just wanted to confirm our observation. Thank you.

Dear Salma,

Thank you for your question.

Your understanding is correct. At level 0 you have the image at the initial highest resolution (~0,25 microns/pixel). The next image levels represent the same image downsampled by a factor of 4. The pixel in the level 1(~1,0 microns/pixel) image covers the area corresponding to 4x4 pixels in the level 0, the pixel in the level 2(~4,0 microns/pixel) image covers the area corresponding to 16x16 pixels in the level 0, the pixel in the level 3(~16,0 microns/pixel) image covers the area corresponding to 64x64 pixels in the level 0, and so on... I hope this helps, Do not hesitate to reach out in case of any further questions.

Kind regards,

Khrystyna