GD Module

stevencl2000 has asked for the wisdom of the Perl Monks concerning the following question:

I have problems using GD module. Really hope that you could help. I have tried calling GD module using a simple cgi script, and it worked. But then, I tried on a more complicated script, where this script processes questions population, it will display characters like below, instead of bar charts.

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+NS@УІУ&#732;f 4IDATx&#339;У][&#8211;ТЋ*У)УЄТЃFУ&#8218;ТЊ&#339;;УУМ
+ТЇrУ&#402;CУЅU@)LТГУ&#65533;I' У&#8230;f У&#710;У&#65533;JУЁУ&#8225;У
+Й&#65533;&#8230;У&#8222;У&#65533;&#8230;ТЖiУЁ"%У&#8225;УВ@У&#8216;&У&
+#8222;УЂТЙ@&#8211;vУМТИ4&#8212;У&#8217;УД&#339;hУО8) &#8249;gТГ[1]
+[1][1][1][1][1]У&#8225;\VhУ ТИУ&#8230;У У&#8224;&#8217;xТЃ&#8249;'VТЈ
+&#8218;&#353;УЈТЗ&#8211;.&#339;k{У&#352;h&#8209;c]У&#8250;:ТЌТЄ db
+У ТИ@У&#8211;ТЅУ&#8221;У&#8217;%iSТК'ТЊУ У&#339;@УАУИУ&#8220;УЅxpУ
+НOУПrУЏУЊ ТИТЖ+CУГ&#381;&#8249;ТД#У&#8222;(УЙ!ZCТНУЗ |H&#710;У&#8216
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+;ТЁ&0_У&#65533;2ТІ&#65533;У&#8216;0&#8230;&#338;&#8224;)d4L!ТЃa  У&#
+382;УИ&#710;&#382;УЁТЄvУ&#65533;УОУМУЊi6ТМУБ&#8216;mУЗ&#8224;У&#65533
+;ТЏ&#382;УІУ&#402;У&#65533;У&#8221;=D)ТЄУОУЕУ&#339;&#8240;&#339;n&#
+338;У&#8224;uL!ТЃa  SУ&#710;h&#732;BFУ&#402;2ТО^У&#8224;BУ&#8218;УЃp
+УЇТКУ&#8218;qУЏУ У&#8217;BdУЂiУМc&#8230;< УД5УВ0У&#8221;qv#QТПУЄТБУ&#
+8249;&#352;УО&#8226;9&#8211;ТОТЙУ&#8482;&#376;УЅ8&#8211;~pfOТЌBУА^d&#
+339;&#8218;S#D-У&#732;GУ&#339;ТЗ9TУ&#402;Zb{7&#353;ТМУЏ&#8218;d&#381
+;M =У&#338;M$&#381;cУ&#338;&#8250;[!NpDУ&#8224;Y@Y'DТЊ)&#8250;NУ&#822
+2;QУ&#732;УЗ*ТЌУ&#382;ТБ У&#65533;ТЅo&#381;ТЉcFpz%72L!УЁNBУЁ.>&#8230;
+УЃУ&#65533;УМZp&#8240;m&#65533;УОУ&#8221;У&#8230;УОL!ТЃaD!H-2У&#352;a
+X!&#710;У&#8250;+УЙУЋ0ТЈУЕ_VУЏТМТЇ0ТЂТЁN ТЊУЛ[У&#381;&#65533;(У&#8222
+;&#8364;ТЙУ&#376;У&#339;УП&#8222;&#352;ТИТЉo00&#8217;IENDТЎB`&#8218;
[download]

PLEASE HELP.

Edit by castaway, added tags to reduce mess, original has actual strange characters instead of HTML entities

Comment on GD Module Download Code

Replies are listed 'Best First'.
Re: GD Module by castaway (Parson) on May 18, 2004 at 10:58 UTC
Hi, it's difficult to help without knowing what actual code you are using. That output looks like an actual PNG type image, which is perfectly legal for GD. I can only guess that your cgi script is not outputting the correct HTTP headers to tell the browser that the data is a PNG. Please post your actual code, then we can help. C.	[reply]
Re: GD Module by Abigail-II (Bishop) on May 18, 2004 at 11:51 UTC
Edit by castaway, added tags to reduce mess, original has actual strange characters instead of HTML entities Yeah, but I strongly doubt the OP saw what's now being displayed. I don't belief a raw PNG file contains HTML entities for Unicode characters. The file might have started with `00/0PNG`, but not with `‰PNG`. Abigail	[reply] [d/l] [select]
Re: Re: GD Module by tachyon (Chancellor) on May 18, 2004 at 11:58 UTC
Despite any editing I think the statistical chances of a script randomly producing /^.PNG....IHDH/ and not being a PNG being displayed as plain text in a browser secondary to missing Content-Type: image/png headers is about 0. To be pedantic it is perhaps 1/18446744073709551616 (256**8) FWIW which is not much. cheers tachyon	[reply]