python - 如何获取 QPixmap 或 QImage 像素的 RGB 值 - Qt, PyQt

Question

基于这个答案https://stackoverflow.com/a/769221/544721 ，我在抓取区域中制作了以下代码打印值:

import sys
from PyQt4.QtGui import QPixmap, QApplication
app = QApplication(sys.argv)

# img is QImage type
img = QPixmap.grabWindow(
        QApplication.desktop().winId(),
        x=00,
        y=100,
        height=20,
        width=20,
        ).toImage()

for x in range(0,20):
    for y in range(0,20):
        print( "({},{}) = {}".format( x,y,(img.pixel(x,y)) ) )

但是像素是这样显示的:

(0,0) = 4285163107
(0,1) = 4285163107
(0,2) = 4285163107
(0,3) = 4285163107
(0,4) = 4285163107
(0,5) = 4285163107

如何获取QImage(从QPixmap获得)像素的RGB值？ (最好是在 16、24、32 屏幕位深度下工作的解决方案)？

示例输出:

(0,0) = (0,0,0)
...
(10,15) = (127,15,256)

(Linux 的解决方案，用 Python3 编写)

Answer 1

您看到的问题是从 img.pixel() 返回的数字实际上是一个 QRgb 值，它是一个独立于格式的值。然后，您可以将其转换为正确的表示形式:

import sys
from PyQt4.QtGui import QPixmap, QApplication, QColor
app = QApplication(sys.argv)

# img is QImage type
img = QPixmap.grabWindow(
        QApplication.desktop().winId(),
        x=00,
        y=100,
        height=20,
        width=20,
        ).toImage()

for x in range(0,20):
    for y in range(0,20):
        c = img.pixel(x,y)
        colors = QColor(c).getRgbF()
        print "(%s,%s) = %s" % (x, y, colors)

输出

(0,0) = (0.60784313725490191, 0.6588235294117647, 0.70980392156862748, 1.0)
(0,1) = (0.60784313725490191, 0.6588235294117647, 0.70980392156862748, 1.0)
(0,2) = (0.61176470588235299, 0.6588235294117647, 0.71372549019607845, 1.0)
(0,3) = (0.61176470588235299, 0.66274509803921566, 0.71372549019607845, 1.0)

QImage docs :

The color of a pixel can be retrieved by passing its coordinates to the pixel() function. The pixel() function returns the color as a QRgb value indepedent of the image's format.