  Full-color imaging is significant in digital pathology. Compared with a
grayscale image or a pseudo-color image that only contains the contrast
information, it can identify and detect the target object better with color
texture information. Fourier ptychographic microscopy (FPM) is a
high-throughput computational imaging technique that breaks the tradeoff
between high resolution (HR) and large field-of-view (FOV), which eliminates
the artifacts of scanning and stitching in digital pathology and improves its
imaging efficiency. However, the conventional full-color digital pathology
based on FPM is still time-consuming due to the repeated experiments with
tri-wavelengths. A color transfer FPM approach, termed CFPM was reported. The
color texture information of a low resolution (LR) full-color pathologic image
is directly transferred to the HR grayscale FPM image captured by only a single
wavelength. The color space of FPM based on the standard CIE-XYZ color model
and display based on the standard RGB (sRGB) color space were established.
Different FPM colorization schemes were analyzed and compared with thirty
different biological samples. The average root-mean-square error (RMSE) of the
conventional method and CFPM compared with the ground truth is 5.3% and 5.7%,
respectively. Therefore, the acquisition time is significantly reduced by 2/3
with the sacrifice of precision of only 0.4%. And CFPM method is also
compatible with advanced fast FPM approaches to reduce computation time
further.
