“High contrast” is selected on the left image. Below is an automatically generated contrast chart. Fonts are sorted correctly.
But I am confused by the absolute illogicality of the chart: “High contrast” selected above should mean "high value of contrast ", but on the Contrast chart it corresponds to the minimum contrast values. “Low Contrast” is selected on the right image - it corresponds to the high contrast values on the chart.
What is contrast? It is the ratio between two values in the font: the width of the vertical and horizontal lines in the font. But which of them is in the denominator and which is in the numerator? Judging by the chart, you divide the width of the horizontal lines by the width of the vertical lines. It seems to me that this is the error.
If you do the opposite: divide the width of the vertical lines by the width of the horizontal lines, then a large difference between them (“High contrast”) will give you a high value of contrast on the right side of the chart, and with a small difference in widths (“Low contrast”) you will get a low value of contrast on the left side of the chart. The chart and values will become absolutely logical.
