imagecreatefromjpeg failing with lack of memory

**Erwin Moller** · Jul 17 '05, 08:01 AM

Re: imagecreatefrom jpeg failing with lack of memory

Simon Stewart wrote:
[color=blue]
> Has anyone else experience of imagecreatefrom jpeg failing with an error
> message about memory even though the size of the image being uploaded is
> nothing like the space available to the script?
>
> Is imagecreatefrom jpeg particularly memory hungry?
>
> Immediately prior to the failure memory is given as 2405072
> The jpeg being uploaded is 812201 in size
> Smaller jpegs work fine. jpegs created by different means all seem to
> fail if the size is around 500k plus.
>
> Error message is
> Fatal error: Allowed memory size of 16777216 bytes exhausted at (null):0
> (tried to allocate 3264 bytes) in
> /home/virtual/site216/fst/var/www/html/mv/private/mvaddinfoinc.ph p on line
> 1997
>
> PHP version is 4.3.3 on a shared server
> GD version is bundled (2.0.15 compatible)
> Memory limit is set to 16M
> Max upload is set to 16M
>
>
> if (function_exist s('memory_get_u sage')) {
> $mem_in_use= memory_get_usag e();
> }
> else {
> $mem_in_use="me mory usage indeterminable" ;
> }
> dev_echo("memor y usage= $mem_in_use" );
> $src_img = imagecreatefrom jpeg("$temp_ful lpicname");
> if (!$src_img) {
> $GLOBALS[InfoMsg]->MsgAdd("Coul d not create image from jpeg");
> unlink ( $temp_fullpicna me);
> return false;
> }[/color]

Hi Simon,

I think you have to estimate how much memory is needed for your jpg to store
it in memory with truecolor.
jps is a heavily compressed format, so your 500K filesize doesn't say a lot.
You need to use the pixels. (width times height)

example:
If your jpg is 2000X2000 pixels, that is 4.000.000 pixels.
If stored truecolor you need (i think)
1 byte R
1 byte G
1 byte B
1 byte alpha channel (transparancy)

So that is 4.000.000 times 4 bytes is around 16 megs.

(Note: I am unsure if PHP will want to allocate all that memory when it
creates an image based on a JPG. I could be possible to use only a part,
but I expect PHP to want to load it all in memory.)

Solution is simple: Try to increase the memory allocated to PHP in php.ini
to get around this problem. Or use smaller images.

Regards,
Erwin Moller

**Simon Stewart** · Jul 17 '05, 08:02 AM

Re: imagecreatefrom jpeg failing with lack of memory

Erwin
Thanks for your comments. It turns out that with around 13.5Mb free, I
could upload a picture of around 2430000 pixels. This seems to be
equivalent to roughly 5.5 bytes per pixel at least for the picture I was
testing with.
Simon Stewart.

"Erwin Moller"
<since_humans_r ead_this_I_am_s pammed_too_much @spamyourself.c om> wrote in
message news:4125ce66$0 $568$e4fe514c@n ews.xs4all.nl.. .[color=blue]
>
> Hi Simon,
>
> I think you have to estimate how much memory is needed for your jpg to[/color]
store[color=blue]
> it in memory with truecolor.
> jps is a heavily compressed format, so your 500K filesize doesn't say a[/color]
lot.[color=blue]
> You need to use the pixels. (width times height)
>
> example:
> If your jpg is 2000X2000 pixels, that is 4.000.000 pixels.
> If stored truecolor you need (i think)
> 1 byte R
> 1 byte G
> 1 byte B
> 1 byte alpha channel (transparancy)
>
> So that is 4.000.000 times 4 bytes is around 16 megs.
>
> (Note: I am unsure if PHP will want to allocate all that memory when it
> creates an image based on a JPG. I could be possible to use only a part,
> but I expect PHP to want to load it all in memory.)
>
> Solution is simple: Try to increase the memory allocated to PHP in php.ini
> to get around this problem. Or use smaller images.
>
> Regards,
> Erwin Moller
>
>
>[/color]

imagecreatefromjpeg failing with lack of memory

imagecreatefromjpeg failing with lack of memory

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