哪个兄弟知道:如何得到windows画布的最大高度/最大宽度(注意是windows画布)及如何解决

self.Image1.Height := 1000000;
  self.Image1.Canvas.TextOut(1000000,10000,'TEST');
  就会出错.
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Debugger Exception Notification
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Project Project1.exe raised exception class EOutOfResources with message '存储空间不足，无法处理此命令。
'. Process stopped. Use Step or Run to continue.
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OK   Help
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