How PHP uses headers to download images directly

How does PHP use the header to download images directly?
is not compressed package, but the picture format directly download, such as JPG, PNG format picture with the header function directly download, solve

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1, hit the header
2, output picture

No? PHP MANUAL:GD
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Search Content-disposition HTTP

PHP code

!--? php//We ll be outputting a PNG imageheader (' Con Tent-type:image/png ');//It'll be called Hello.pngheader (' content-disposition:attachment; filename= ' hello.png '); BR/-->------Solution--------------------
 Direct download should be the header to jump to the URL of the image 
 the path to the sample is Http://test.com/pic/test1.jpg 
 

   
 Header ("location:http://test.com/pic/test1.jpg") 
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     Explore  
    
 
    
 Direct download should be to jump to the URL of the image with the header 
    
 The path is http://test.com/pic/test1.jpg 
    
 
    
 to download 
    
 Header ("Location : Http://test.com/pic/test1.jpg ") 
    
 
    
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 But the landlord seems to want to download-,-I did not see, #2是真相 . 
 