Grunnleggende konsepter
Histropy is an interactive Python program that allows users to quantify selected features of 2D gray-scale images by analyzing their pixel intensity histograms, including calculating Shannon entropy and root-mean-square contrast for user-selected histogram sections.
Sammendrag
The Histropy computer program is designed for the quantitative analysis of 2D gray-scale images through the examination of their pixel intensity histograms. The program can handle images in various formats (JPG/JPEG, PNG, GIF, BMP, or baseline TIF/TIFF) with 8-bit information depth and up to 1024 pixels on each side.
The key features of Histropy include:
Generating a histogram of the pixel intensity values for a selected image, with the ability to switch between linear and log-base-10 scales for the y-axis.
Allowing the user to select a range of pixel intensity levels along the histogram's x-axis, either by directly typing in the values or by clicking on the histogram.
Calculating and displaying various metrics for the selected range, including the number of pixels, percentage of total pixels, Shannon entropy (Monkey Model), mean, root-mean-square contrast, and total pixel intensity.
Enabling the overlay of multiple images' histograms for visual comparison, with the corresponding calculation data displayed in matching colors.
Providing navigation tools to zoom, pan, and reset the histogram view, as well as the ability to save the full histogram workspace plot as a PNG image.
The program's primary use case within the authors' research group is to quantitatively distinguish between genuine symmetries and pseudosymmetries in 2D crystal patterns, by analyzing the pixel intensity histograms and calculating the Shannon entropy and root-mean-square contrast. However, the program's functionality could be extended to other applications involving the analysis of 2D data tables or images.
Statistikk
The crystal pattern in the background of Figure A1a has a histogram with a few pronounced peaks.
The histogram of the noisy version of the 512x512 pixel cutout of the crystal pattern (displayed in blue in Figure A2) shows visual "sharpenings" and relative shifts of the peaks after crystallographic image processing to enforce the symmetries of the non-disjoint plane symmetry groups p2 (orange) and p4 (green).
Sitater
"The visual analysis that a histogram facilitates, combined with the quantitative information that can be extracted from it, gives histograms a wide range of applications, ranging from analyzing the distributions of test scores in a classroom to probabilistically characterizing the behavior of river discharge."
"Competing computer programs, e.g. the histogram routines that are part of the well-known electron crystallography software CRISP (Hovm¨oller, Oleynikov & Zou, 2011), do not typically offer the functionality desired for our studies."