Open the existing pdf file Using PHP

[vssp]

Hai friends

I need one clarification. I am usuing php code to read the existing pdf file .
Some files open correctly but some pdf file open below format in browser.

I not clear how its come. Biu the same coading open the existing pdf file correctly. Please help me . I am going to nuts this error.

PDF-1.5
%äãÏÒ
1 0 obj
[/PDF/ImageB/ImageC/ImageI/Text]
endobj
3 0 obj
<</Type/XObject
/Subtype/Form
/FormType 1
/Matrix[1 0 0 1 0 -432]
/BBox[0 432 612 1224]
/Resources<</XObject<</3 4 0 R
>>
/ProcSet[/PDF
/ImageB
]
>>/Length 91
/Filter/FlateDecode
>>
stream

[rameshmrgn]

whats the code u r using to read pdf files?

[vssp]

I am using pdf functions only