QImage，QPixmap的，QBitmap，QPicture的区别

Qt provides four classes for handling image data: QImage, QPixmap, QBitmap and QPicture.

Qt提供了4种类型类操作图像数据：QImage，QPixmap的，QBitmap和QPicture。

QImage is designed and optimized for I/O, and for direct pixel access and manipulation,

QImage是为I / O设计和优化的，为了直接的像素访问和操作，

while QPixmap is designed and optimized for showing images on screen. QBitmap is only

然而QPixmap是为在屏幕上现实图片设计和优化的，QBitmap只是是继承QPixmap

a convenience class that inherits QPixmap, ensuring a depth of 1. The isQBitmap() function

的一个易使用的类，保证了深度为1， isQBitmap() 函数当对象是真的bitmap返回true

returns true if a QPixmap object is really a bitmap, otherwise returns false. Finally, the QPicture

否则反悔false，最后 QPicture类

class is a paint device that records and replays QPainter commands.

QPicture类是绘制设备，主要用来记录和回放QPainter命令