When acquiring images in microscopy, the image files that are stored contain two main things:
# ''image data''
, which is essentially 'pixel values'# ''metadata'' , information on the image data including pixel size, bit depth, dimension and objective information, etc.
Metadata is essential to correctly read image data; for example, to have accurate measurements, the image needs to be calibrated according to the correct/associated pixel size. Saving and preserving metadata is key in quantitative image analysis.