Memory problem with imagecreatefromstring function

**Agelmar** · Jul 17 '05, 02:21 AM

Re: Memory problem with imagecreatefrom string function

A few things... one, you should NOT call unset() on a MySQL result. Call
mysql_free_resu lt.
2. gd images take up a considerable amount of memory, and if it's using a
shared module (e.g. php was compiled with --enable-gd=shared or whatever) as
opposed to it being compiled in, that will take a bit more memory as well.

Matthieu MARC wrote:[color=blue]
> Hi everybody,
>
> I'm writting a script which take image data from mysql (blob) and draw
> the image to screen.
>
> At the end of the message you will find my php code. I put lots of
> numbered message about the memory usage.
>
> The image in the database is about 520ko.
>
>
> Here is the output in my browser :
>
> -1 - 34816
> 0 - 123672
> 0bis - 652064
> 1 - 6693928
> 2 - 6693928
> 3 - 8957256
> 4 - 8957336
>
> What I see is just before the use of the function
> imagecreatefrom string, the script is using about 650ko, and just
> after about 6,5Mo !
>
> I do not understand why it is using so much memory for just a 'little'
> picture.
>
> I'm using redhat fedora 1 linux distribution.
>
> php-4.3.3
> httpd-2.0.47
> gd-2.0.15
>
> Is someone understand my problem ?
>
> Thanks
>
> Matthieu MARC
>
>
>
> ------ PHP CODE -----
> <?php
>
> echo "-1 - ".memory_get_us age() . "\n ";
> include_once("i nclude/include.php");
>
> $photo_id = $_POST['id'];
>
> if ( $photo_id == '' ){
> $photo_id = $_GET['id'];
> }
>
> echo "0 - ".memory_get_us age() . "\n ";
> $photo_data = db_getphotodata fromid(session_ getuser(),$phot o_id);
>
>
> if ( $photo_data != NULL ){
>
> # header("Content-Type: ".$photo_da ta['type']);
>
> $size = 600;
>
> echo "0bis - ".memory_get_us age() . "\n ";
>
> $src = imagecreatefrom string($photo_d ata['data']);
> unset($photo_da ta);
>
> echo "1 - ".memory_get_us age() . "\n ";
>
> $width = imagesx($src);
> $height = imagesy($src);
> $aspect_ratio = $height/$width;
>
> if ($height <= $size) {
> $new_w = $width;
> $new_h = $height;
> } else {
> $new_h = $size;
> $new_w = abs($new_h / $aspect_ratio);
> }
>
> echo "2 - ".memory_get_us age() . "\n ";
>
> $img = imagecreatetrue color ($new_w,$new_h) ;
>
> echo "3 - ".memory_get_us age() . "\n ";
>
> imagecopyresamp led
> ($img,$src,0,0, 0,0,$new_w,$new _h,$width,$heig ht);
>
> echo "4 - ".memory_get_us age() . "\n ";
>
> imagejpeg($img, '', 90);
>
> echo "5 - ".memory_get_us age() . "\n ";
>
> imagedestroy($i mg);
> } else {
>
> header ("Content-Type: text/html");
> print ("no photo found");
> }
>[color=green]
>>[/color]
>
> ------ END PHP CODE ------[/color]

**Andy Hassall** · Jul 17 '05, 02:21 AM

Re: Memory problem with imagecreatefrom string function

On Fri, 09 Jan 2004 15:25:05 +0100, Matthieu MARC
<matthieu.marc@ crisi.unicaen.f r> wrote:
[color=blue]
>I'm writting a script which take image data from mysql (blob) and draw
>the image to screen.
>
>At the end of the message you will find my php code. I put lots of
>numbered message about the memory usage.
>
>The image in the database is about 520ko.[/color]

In what format?
[color=blue]
>What I see is just before the use of the function imagecreatefrom string,
> the script is using about 650ko, and just after about 6,5Mo ![/color]

If it's a compressed format in the database (JPEG, PNG, GIF), expanding from
520kb to 6.5Mb isn't too surprising - GD is likely to be using an uncompressed
format in memory.

--
Andy Hassall <andy@andyh.co. uk> / Space: disk usage analysis tool
<http://www.andyh.co.uk > / <http://www.andyhsoftwa re.co.uk/space>

**Chung Leong** · Jul 17 '05, 02:21 AM

Re: Memory problem with imagecreatefrom string function

You should resize the picture first, then it into the database. Resampling a
image takes quite a bit of time. You don't want to do it on every request.

Uzytkownik "Matthieu MARC" <matthieu.marc@ crisi.unicaen.f r> napisal w
wiadomosci news:btmdkn$h3j 1$1@baligan1.un icaen.fr...[color=blue]
>
> Hi everybody,
>
> I'm writting a script which take image data from mysql (blob) and draw
> the image to screen.
>
> At the end of the message you will find my php code. I put lots of
> numbered message about the memory usage.
>
> The image in the database is about 520ko.
>
>
> Here is the output in my browser :
>
> -1 - 34816
> 0 - 123672
> 0bis - 652064
> 1 - 6693928
> 2 - 6693928
> 3 - 8957256
> 4 - 8957336
>
> What I see is just before the use of the function imagecreatefrom string,
> the script is using about 650ko, and just after about 6,5Mo !
>
> I do not understand why it is using so much memory for just a 'little'
> picture.
>
> I'm using redhat fedora 1 linux distribution.
>
> php-4.3.3
> httpd-2.0.47
> gd-2.0.15
>
> Is someone understand my problem ?
>
> Thanks
>
> Matthieu MARC
>
>
>
> ------ PHP CODE -----
> <?php
>
> echo "-1 - ".memory_get_us age() . "\n ";
> include_once("i nclude/include.php");
>
> $photo_id = $_POST['id'];
>
> if ( $photo_id == '' ){
> $photo_id = $_GET['id'];
> }
>
> echo "0 - ".memory_get_us age() . "\n ";
> $photo_data = db_getphotodata fromid(session_ getuser(),$phot o_id);
>
>
> if ( $photo_data != NULL ){
>
> # header("Content-Type: ".$photo_da ta['type']);
>
> $size = 600;
>
> echo "0bis - ".memory_get_us age() . "\n ";
>
> $src = imagecreatefrom string($photo_d ata['data']);
> unset($photo_da ta);
>
> echo "1 - ".memory_get_us age() . "\n ";
>
> $width = imagesx($src);
> $height = imagesy($src);
> $aspect_ratio = $height/$width;
>
> if ($height <= $size) {
> $new_w = $width;
> $new_h = $height;
> } else {
> $new_h = $size;
> $new_w = abs($new_h / $aspect_ratio);
> }
>
> echo "2 - ".memory_get_us age() . "\n ";
>
> $img = imagecreatetrue color ($new_w,$new_h) ;
>
> echo "3 - ".memory_get_us age() . "\n ";
>
> imagecopyresamp led
> ($img,$src,0,0, 0,0,$new_w,$new _h,$width,$heig ht);
>
> echo "4 - ".memory_get_us age() . "\n ";
>
> imagejpeg($img, '', 90);
>
> echo "5 - ".memory_get_us age() . "\n ";
>
> imagedestroy($i mg);
> } else {
>
> header ("Content-Type: text/html");
> print ("no photo found");
> }
>
> ?>
>
> ------ END PHP CODE ------
>[/color]

Memory problem with imagecreatefromstring function

Memory problem with imagecreatefromstring function

Comment

Comment

Comment