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pythoncolorshistogrampyqtgraph

pyqtgraph histogram LUT Item - how to change color?

I want to change the color of the blue bar in the histogram.

I've already changed the color of the background: 

.ui.histogram.setBackground(background= pg.mkColor(37,37,37))

But I don´t know how to change the color of the Blue Bar. (I imported pyqtgraph as pg)

Does anybody know how to do this?

Thank you in advance

Solution

  • It's hard for me to make a answer that I'm certain of, because I don't have all information. For instance what is ui in your question? Next time please make an MVCE.

    Anyway, assuming you have a ImageView object called imgView the following should work:

    alpha = 50
region = imgView.histogram.item.region
region.setBrush(color=(255, 0, 0, alpha))
for line in region.lines:
    line.setPen(color=(255, 0, 0, 255))

    Make sure that alpha is smaller than 128. The value of 2 * alpha will be used when you hover above the region, and you will get a warning if it exceeds 256.

    By the way, the imgView.histogram.item is a HistogramLutItem. I got my answer by looking at its source code.