Re: imagecreatetruecolor sometimes causes forced-download of index.php for some JPEG images


Andy Hassall wrote:
On 4 Aug 2006 14:44:18 -0700, "comp.lang.php" <phillip.s.powell@xxxxxxxxx>
wrote:

Actually I was wrong and found out the problem isn't
imagecreatetruecolor() but it happens to be imagecreatefromjpeg(),
again, only with certain JPEG images. There is nothing I could find
that distinguished one JPEG from another; they're all roughly the same
size, compression, having the same permissions, group and onwership,
all the same amount of color, all from the same CD source.

I thought it was exceeding of memory_limit, however, using
memory_get_usage() I am finding the memory allotted for use in the
script is far below memory_limit, however, it still "dies".

If imagecreatefromjpeg() is exhausting the memory you're not going to be able
to see it from memory_get_usage(); you'll be below the limit before the call,
and it'll die during the call - you won't be able to see it exceeding the limit
apart from the error message (you have turned error_reporting back up to E_ALL,
right?)

Yes, to no avail. It still forces you to download "index.php". There
is no error, no warning, nothing. PHP doesn't register any kind of
message whatseover; in fact, it sounds more like a segfault, in short,
*there is no PHP anymore*


And next:

(1) What _is_ output by the script when it fails?


Nothing. You're forced to download index.php

(2) Can you reduce it to a _minimal_ test script - sounds like it could go all
the way down to imagecreatefromjpeg() followed by imagejpeg() ?


It doesn't. It dies right at imagecreatefromjpeg() every time. Never
gets any further than that.

(3) If you still can't work it out from there can you make available to the
group examples of (a) an image that fails and (b) a similar one that doesn't
fail?


I don't have an immediate way of producing them publically; they're on
a government-protected server that's not open to the general public; I
would have to attach them here, which I don't think Google Groups
allows to do.

--
Andy Hassall :: andy@xxxxxxxxxxx :: http://www.andyh.co.uk
http://www.andyhsoftware.co.uk/space :: disk and FTP usage analysis tool

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