Last updated: Sat, 24 Mar 2007

LXIV. Image Functions

Úvod

PHP is not limited to creating just HTML output. It can also be used to create and manipulate image files in a variety of different image formats, including gif, png, jpg, wbmp, and xpm. Even more convenient, PHP can output image streams directly to a browser. You will need to compile PHP with the GD library of image functions for this to work. GD and PHP may also require other libraries, depending on which image formats you want to work with.

You can use the image functions in PHP to get the size of JPEG, GIF, PNG, SWF, TIFF and JPEG2000 images.

With the exif extension, you are able to work with information stored in headers of JPEG and TIFF images. This way you can read meta data generated by digital cameras. The exif functions do not require the GD library.

Poznámka: Read the requirements section about how to expand image capabilities to read, write and modify images. To read meta data of pictures taken by digital cameras you need the above mentioned exif extension.

Požadavky

If you have the GD library (available at » http://www.boutell.com/gd/) you will also be able to create and manipulate images.

The format of images you are able to manipulate depend on the version of GD you install, and any other libraries GD might need to access those image formats. Versions of GD older than gd-1.6 support GIF format images, and do not support PNG, where versions greater than gd-1.6 and less than gd-2.0.28 support PNG, not GIF. GIF support was re-enabled in gd-2.0.28.

Poznámka: Since PHP 4.3 there is a bundled version of the GD lib. This bundled version has some additional features like alpha blending, and should be used in preference to the external library since its codebase is better maintained and more stable.

Poznámka: Support for GD 1.x has been removed as of PHP 6.0.0, which requires GD 2.0.33 or later.

You may wish to enhance GD to handle more image formats.

Tabulka 113. Supported image formats

Image format	Library to download	Notes
`gif`		Only supported in GD versions older than gd-1.6 and newer than gd-2.0.28. Read-only GIF support is available with PHP 4.3.0 and the bundled GD-library. Write support is available since PHP 4.3.9 and PHP 5.0.1.
`jpeg-6b`	» ftp://ftp.uu.net/graphics/jpeg/	When buliding the jpeg-v6b library (prior to building PHP) you must use the `--enable-shared` option in the configure step. If you do not, you will receive an error saying `libjpeg.(a\|so) not found` when you get to the configure step of building PHP.
`png`	» http://www.libpng.org/pub/png/libpng.html	Only supported in GD versions greater than gd-1.6.
`xpm`	» ftp://metalab.unc.edu/pub/Linux/libs/X/!INDEX.html	It's likely you have this library already available, if your system has an installed X-Environment.

You may wish to enhance GD to deal with different fonts. The following font libraries are supported:

Tabulka 114. Supported font libraries

Font library	Download	Notes
`FreeType 1.x`	» http://www.freetype.org/	Support removed as of PHP 6.0.0
`FreeType 2`	» http://www.freetype.org/
`T1lib`	» ftp://sunsite.unc.edu/pub/Linux/libs/graphics/)	Support for Postscript Type 1 fonts.

Instalace

To enable GD-support configure PHP --with-gd[=DIR], where DIR is the GD base install directory. To use the recommended bundled version of the GD library (which was first bundled in PHP 4.3.0), use the configure option --with-gd. GD library requires libpng™ and libjpeg™ to compile.

In Windows, you'll include the GD2 DLL php_gd2.dll as an extension in php.ini. The GD1 DLL php_gd.dll was removed in PHP 4.3.2. Also note that the preferred truecolor image functions, such as imagecreatetruecolor(), require GD2.

To disable GD support in PHP 3 add --without-gd to your configure line.

Enhance the capabilities of GD to handle more image formats by specifying the --with-XXXX configure switch to your PHP configure line.

Tabulka 115. Supported image formats

Image Format	Configure Switch
`jpeg-6b`	To enable support for jpeg-6b add `--with-jpeg-dir=DIR`.
`png`	To enable support for png add `--with-png-dir=DIR`. Note, libpng requires the zlib library, therefore add `--with-zlib-dir[=DIR]` to your configure line.
`xpm`	To enable support for xpm add `--with-xpm-dir=DIR`. If configure is not able to find the required libraries, you may add the path to your X11 libraries.

Poznámka: When compiling PHP with libpng, you must use the same version that was linked with the GD library.

Enhance the capabilities of GD to deal with different fonts by specifying the --with-XXXX configure switch to your PHP configure line.

Tabulka 116. Supported font libraries

Font library	Configure Switch
`FreeType 1.x`	To enable support for FreeType 1.x add `--with-ttf[=DIR]`.
`FreeType 2`	To enable support for FreeType 2 add `--with-freetype-dir=DIR`.
`T1lib`	To enable support for T1lib (Postscript Type 1 fonts) add `--with-t1lib[=DIR]`.
`Native TrueType string function`	To enable support for native TrueType string function add `--enable-gd-native-ttf`.

Konfigurace běhu

There are no image specific configurations but you may be interested in the exif extension directives.

Varování

Image functions are very memory intensive. Be sure to set memory_limit high enough.

Typy prostředků

This extension defines two resource types: an image identifier and a font identifier.

Předdefinované konstanty

Tyto konstanty jsou definovány tímto rozšířením a budou k dispozici pouze tehdy, bylo-li rozšíření zkompilováno společně s PHP nebo dynamicky zavedeno za běhu.

IMG_GIF (integer)
IMG_JPG (integer)
IMG_JPEG (integer)
IMG_PNG (integer)
IMG_WBMP (integer)
IMG_XPM (integer)
IMG_COLOR_TILED (integer)
IMG_COLOR_STYLED (integer)
IMG_COLOR_BRUSHED (integer)
IMG_COLOR_STYLEDBRUSHED (integer)
IMG_COLOR_TRANSPARENT (integer)
IMG_ARC_ROUNDED (integer)
IMG_ARC_PIE (integer)
IMG_ARC_CHORD (integer)
IMG_ARC_NOFILL (integer)
IMG_ARC_EDGED (integer)
IMAGETYPE_GIF (integer)
IMAGETYPE_JPEG (integer)
IMAGETYPE_PNG (integer)
IMAGETYPE_SWF (integer)
IMAGETYPE_PSD (integer)
IMAGETYPE_BMP (integer)
IMAGETYPE_WBMP (integer)
IMAGETYPE_XBM (integer)
IMAGETYPE_TIFF_II (integer)
IMAGETYPE_TIFF_MM (integer)
IMAGETYPE_IFF (integer)
IMAGETYPE_JB2 (integer)
IMAGETYPE_JPC (integer)
IMAGETYPE_JP2 (integer)
IMAGETYPE_JPX (integer)
IMAGETYPE_SWC (integer)
PNG_NO_FILTER (integer)
PNG_FILTER_NONE (integer)
PNG_FILTER_SUB (integer)
PNG_FILTER_UP (integer)
PNG_FILTER_AVG (integer)
PNG_FILTER_PAETH (integer)
PNG_ALL_FILTERS (integer)

Příklady

Příklad 767. PNG creation with PHP


<?php



header("Content-type: image/png");

$string = $_GET['text'];

$im     = imagecreatefrompng("images/button1.png");

$orange = imagecolorallocate($im, 220, 210, 60);

$px     = (imagesx($im) - 7.5 * strlen($string)) / 2;

imagestring($im, 3, $px, 9, $string, $orange);

imagepng($im);

imagedestroy($im);



?>

This example would be called from a page with a tag like: <img src="button.php?text=text">. The above button.php script then takes this "text" string and overlays it on top of a base image which in this case is "images/button1.png" and outputs the resulting image. This is a very convenient way to avoid having to draw new button images every time you want to change the text of a button. With this method they are dynamically generated.

Obsah

gd_info — Retrieve information about the currently installed GD library
getimagesize — Get the size of an image
image_type_to_extension — Get file extension for image type
image_type_to_mime_type — Get Mime-Type for image-type returned by getimagesize, exif_read_data, exif_thumbnail, exif_imagetype
image2wbmp — Output image to browser or file
imagealphablending — Set the blending mode for an image
imageantialias — Should antialias functions be used or not
imagearc — Draws an arc
imagechar — Draw a character horizontally
imagecharup — Draw a character vertically
imagecolorallocate — Allocate a color for an image
imagecolorallocatealpha — Allocate a color for an image
imagecolorat — Get the index of the color of a pixel
imagecolorclosest — Get the index of the closest color to the specified color
imagecolorclosestalpha — Get the index of the closest color to the specified color + alpha
imagecolorclosesthwb — Get the index of the color which has the hue, white and blackness nearest to the given color
imagecolordeallocate — De-allocate a color for an image
imagecolorexact — Get the index of the specified color
imagecolorexactalpha — Get the index of the specified color + alpha
imagecolormatch — Makes the colors of the palette version of an image more closely match the true color version
imagecolorresolve — Get the index of the specified color or its closest possible alternative
imagecolorresolvealpha — Get the index of the specified color + alpha or its closest possible alternative
imagecolorset — Set the color for the specified palette index
imagecolorsforindex — Get the colors for an index
imagecolorstotal — Find out the number of colors in an image's palette
imagecolortransparent — Define a color as transparent
imageconvolution — Apply a 3x3 convolution matrix, using coefficient and offset
imagecopy — Copy part of an image
imagecopymerge — Copy and merge part of an image
imagecopymergegray — Copy and merge part of an image with gray scale
imagecopyresampled — Copy and resize part of an image with resampling
imagecopyresized — Copy and resize part of an image
imagecreate — Create a new palette based image
imagecreatefromgd2 — Create a new image from GD2 file or URL
imagecreatefromgd2part — Create a new image from a given part of GD2 file or URL
imagecreatefromgd — Create a new image from GD file or URL
imagecreatefromgif — Create a new image from file or URL
imagecreatefromjpeg — Create a new image from file or URL
imagecreatefrompng — Create a new image from file or URL
imagecreatefromstring — Create a new image from the image stream in the string
imagecreatefromwbmp — Create a new image from file or URL
imagecreatefromxbm — Create a new image from file or URL
imagecreatefromxpm — Create a new image from file or URL
imagecreatetruecolor — Create a new true color image
imagedashedline — Draw a dashed line
imagedestroy — Destroy an image
imageellipse — Draw an ellipse
imagefill — Flood fill
imagefilledarc — Draw a partial ellipse and fill it
imagefilledellipse — Draw a filled ellipse
imagefilledpolygon — Draw a filled polygon
imagefilledrectangle — Draw a filled rectangle
imagefilltoborder — Flood fill to specific color
imagefilter — Applies a filter to an image
imagefontheight — Get font height
imagefontwidth — Get font width
imageftbbox — Give the bounding box of a text using fonts via freetype2
imagefttext — Write text to the image using fonts using FreeType 2
imagegammacorrect — Apply a gamma correction to a GD image
imagegd2 — Output GD2 image to browser or file
imagegd — Output GD image to browser or file
imagegif — Output image to browser or file
imageinterlace — Enable or disable interlace
imageistruecolor — Finds whether an image is a truecolor image
imagejpeg — Output image to browser or file
imagelayereffect — Set the alpha blending flag to use the bundled libgd layering effects
imageline — Draw a line
imageloadfont — Load a new font
imagepalettecopy — Copy the palette from one image to another
imagepng — Output a PNG image to either the browser or a file
imagepolygon — Draws a polygon
imagepsbbox — Give the bounding box of a text rectangle using PostScript Type1 fonts
imagepsencodefont — Change the character encoding vector of a font
imagepsextendfont — Extend or condense a font
imagepsfreefont — Free memory used by a PostScript Type 1 font
imagepsloadfont — Load a PostScript Type 1 font from file
imagepsslantfont — Slant a font
imagepstext — Draws a text over an image using PostScript Type1 fonts
imagerectangle — Draw a rectangle
imagerotate — Rotate an image with a given angle
imagesavealpha — Set the flag to save full alpha channel information (as opposed to single-color transparency) when saving PNG images
imagesetbrush — Set the brush image for line drawing
imagesetpixel — Set a single pixel
imagesetstyle — Set the style for line drawing
imagesetthickness — Set the thickness for line drawing
imagesettile — Set the tile image for filling
imagestring — Draw a string horizontally
imagestringup — Draw a string vertically
imagesx — Get image width
imagesy — Get image height
imagetruecolortopalette — Convert a true color image to a palette image
imagettfbbox — Give the bounding box of a text using TrueType fonts
imagettftext — Write text to the image using TrueType fonts
imagetypes — Return the image types supported by this PHP build
imagewbmp — Output image to browser or file
imagexbm — Output XBM image to browser or file
iptcembed — Embed binary IPTC data into a JPEG image
iptcparse — Parsuje binární IPTC » http://www.iptc.org/ blok do jednotlivých tagů.
jpeg2wbmp — Convert JPEG image file to WBMP image file
png2wbmp — Convert PNG image file to WBMP image file

gd_info

iis_stop_service

Last updated: Sat, 24 Mar 2007

add a note User Contributed Notes
Image Functions

dev at kingthief dot com
28-Mar-2008 09:20


I've developed a well-documented, fairly rock-solid API for creating on the fly, anti-aliased, rounded corner images, including full alpha transparency support for all you PNG lovers.



go here to download the package:

http://sourceforge.net/projects/roundedphp/



go here for a live demo:

http://dev.kingthief.com/demos/roundedphp/



Installation is similar to PEAR.



Enjoy!

henry at corpocuisine dot com
17-Mar-2008 05:39


To troy,



Good demo of GD "tricks"



If safe mode is not: on;

then it will be better to: 

instead of using putenv() 

using the following which will work in any php.ini settings environment.



$fontpath='../../../WINDOWS/fonts/';



$font =$fontpath. 'arial.ttf';

troy --at-- goemr.com
14-Mar-2008 03:09


Here is a fun example Easter Egg drawing that uses a bunch of image functions.  Just in time for Easter 2008.  Enjoy.

<?php



$image = imagecreatetruecolor(400, 500);



$bg = imagecolorallocate($image, 10, 10, 150);

imagefill($image, 0, 0, $bg);



// allocate some colors

$white = imagecolorallocate($image, 255, 255, 255);

$grey = imagecolorallocate($image, 128, 128, 128);

$black = imagecolorallocate($image, 0, 0, 0);



// choose a color for the elipse

$col_ellipse = imagecolorallocate($image, 255, 200, 255);



// draw ellipse shadow

imagefilledellipse($image, 215, 265, 320, 400, $black);



// draw the ellipse

imagefilledellipse($image, 200, 250, 320, 400, $col_ellipse);



//draw arc where plastic egg opens

imagearc($image, 198, 235, 326, 100, 0, 180, $bg);



$colour = imagecolorallocate($image, 100, 0, 200);



$ca = rand(2,5);

$cb = rand(2,5);

$cc = rand(2,5);

$cd = rand(2,5);



${"colour".$ca} = imagecolorallocate($image, 153, 204, 255);

${"colour".$cb} = imagecolorallocate($image, 102, 0, 153);

${"colour".$cc} = imagecolorallocate($image, 204, 153, 204);

${"colour".$cd} = imagecolorallocate($image, 153, 0, 255);



//positions of stars relative to original position



$shift['x'][]=0;  //star 1

$shift['y'][]=0;

$star['color'][] = $colour;



$shift['x'][]=-80;  //star 2

$shift['y'][]=-120;

$star['color'][] = $colour2;



$shift['x'][]=-130; //star 3

$shift['y'][]=10;

$star['color'][] = $colour3;



$shift['x'][]=-10; //star 4

$shift['y'][]=-250;

$star['color'][] = $colour4;



$shift['x'][]=-160; //star 5

$shift['y'][]=-200;

$star['color'][] = $colour5;



for($ii=0; $ii < count($shift['x']); $ii++)

{



// set up array of points for polygon

$values = array(

            230,  330,  

            290,  390, 

            280,  340, 

            240, 380,  

            310, 370,  

            230,  330  

            );



    $shiftX = $shift['x'][$ii];

    $shiftY = $shift['y'][$ii];

    

    foreach ($values as &$val)

    {

        if($i == 1){    $val = $val+$shiftY;    $i++;    }

        else

        {    $val = $val+$shiftX;        $i = 1;    }

    }

    

    

    // draw a star filled in with a circle

    imagefilledpolygon($image, $values, 6, $star['color'][$ii]);

    imagefilledellipse($image, 273+$shiftX, 364+$shiftY, 35, 24, $star['color'][$ii]);

}//end for



// Rotate

$degrees = rand(0,360);



$image= imagerotate($image, $degrees, 0);



imagefilter($image, IMG_FILTER_MEAN_REMOVAL, 0);

imagefilter($image, IMG_FILTER_SMOOTH, 0);



//add some text

$text = 'Easter Egg by Troy Jordan 2008 using only php & gd';



//place font in same path as this script

putenv('GDFONTPATH=' . realpath('.'));



//change this font to the name of your font

$font = 'ACAKZIDE.TTF';



// Add some shadow to the text

imagettftext($image, 18, 0, 13, 21, $grey, $font, $text);



// Add the text

imagettftext($image, 18, 0, 12, 20, $white, $font, $text);



//resize the image

$width = imagesx($image);

$height = imagesy($image);



if($height > 0) { $ratio = $width/$height; }



$rand = rand(25,75);

$perc = $rand/100;



$newwidth = $width * $perc;

$newheight = $height * $perc;



$image2 = imagecreatetruecolor($newwidth, $newheight);



imagecopyresampled($image2, $image, 0, 0, 0, 0, $newwidth, $newheight, $width, $height);



header("Content-type: image/png");

imagepng($image2);



?>

somebody learning php
11-Mar-2008 09:34


This is regarding a note below titled "sampathperera at hotmail dot com - Sri Lanka". It is incomplete. A much better version is at (concat lines below to construct URL):



http://www.planet-source-code.com/vb/scripts/ShowCode.asp?

txtCodeId=739&lngWId=8



If the link is broken, google for Image Verification Tutorial by Darryl Porter.

ph_corp at yahoo dot fr
23-Dec-2007 03:19


<?php



/**

HSL/RGB conversion functions

very useful for a lot of applications

**/



function RBGtoHSL ( $R, $G, $B )

{



    $var_R = ( $R / 255 );

    $var_G = ( $G / 255 );

    $var_B = ( $B / 255 );



    $var_Min = min( $var_R, $var_G, $var_B )

    $var_Max = max( $var_R, $var_G, $var_B )

    $del_Max = $var_Max - $var_Min



    $L = ( $var_Max + $var_Min ) / 2;



    if ( $del_Max == 0 )

    {

       $H = 0

       $S = 0

    }

    else

    {

        if ( $L < 0.5 )

        {

            $S = $del_Max / ( $var_Max + $var_Min );

        }

        else

        {

            $S = $del_Max / ( 2 - $var_Max - $var_Min );

        }



        $del_R = ( ( ( $var_Max - $var_R ) / 6 ) + ( $del_Max / 2 ) ) / $del_Max;

        $del_G = ( ( ( $var_Max - $var_G ) / 6 ) + ( $del_Max / 2 ) ) / $del_Max;

        $del_B = ( ( ( $var_Max - $var_B ) / 6 ) + ( $del_Max / 2 ) ) / $del_Max;



        if ( $var_R == $var_Max )

        {

            $H = $del_B - $del_G;

        }

        else if ( $var_G == $var_Max )

        {

            $H = ( 1 / 3 ) + $del_R - $del_B;

        }

        else if ( $var_B == $var_Max )

        {

            $H = ( 2 / 3 ) + $del_G - $del_R;

        }



        if ( $H < 0 )

        {

            $H += 1;

        }

        if ( $H > 1 )

        {

            $H -= 1

        }



    }



    return array( $H, $S, $L );



}



function HuetoRGB( $v1, $v2, $vH )

{

    if ( $vH < 0 )

    {

        $vH += 1;

    }

    if ( $vH > 1 )

    {

        $vH -= 1;

    }

    if ( ( 6 * $vH ) < 1 )

    {

        return ( $v1 + ( $v2 - $v1 ) * 6 * $vH );

    }

    if ( ( 2 * $vH ) < 1 )

    {

        return ( $v2 );

    }

    if ( ( 3 * $vH ) < 2 )

    {

        return ( $v1 + ( $v2 - $v1 ) * ( ( 2 / 3 ) - $vH ) * 6 );

    }

    return ( $v1 )

}



function HSLtoRGB ( $H, $S, $L )

{



    if ( $S == 0 )

    {

        $R = $L * 255;

        $G = $L * 255;

        $B = $L * 255;

    }

    else

    {

        if ( $L < 0.5 )

        {

            $var_2 = $L * ( 1 + $S );

        }

        else

        {

            $var_2 = ( $L + $S ) - ( $S * $L );

        }



        $var_1 = 2 * $L - $var_2;



        $R = 255 * HuetoRGB( $var_1, $var_2, $H + ( 1 / 3 ) );

        $G = 255 * HuetoRGB( $var_1, $var_2, $H );

        $B = 255 * HuetoRGB( $var_1, $var_2, $H - ( 1 / 3 ) );

    }



    return array( $R, $G, $B );



}



function distance ( $R1, $G1, $B1, $R2, $G2, $B2 )

{

    $result = sqrt ( ( $R1 - $R2 )*( $R1 - $R2 ) + ( $G1 - $G2 )*( $G1 - $G2 ) + ( $B1 - $B2 )*( $B1 - $B2 ) );

    return ( $result );

}



?>

kangaroo232002 at yahoo dot co dot uk
14-Nov-2007 03:51


I have noticed that some functions use quite complicated resizing code, however if you want to specify just one dimension (e.g. resizing an image for a catalogue or social network etc) then you can do it my just getting the percentage reduction of one dimension of the image and applying it to the other, like so:



<?php



$new_width = 150;



//assuming you have already used imageSX(), imageSY() to get the dimensions.



$percentage_reduction = ($new_width / $old_width) * 100;

$new_height = ($old_height / 100) * $percentage_reduction;



?>



This means that images will not be stretched, but will be neater as they are the same width (e.g. facebook).

zilly at adminc dot org
20-Oct-2007 08:10


Here is an Example of what can be done using GD and Php.

There is a whole 3D-Dungeon realized and rendered in Real-Time using GD:

http://www.quizzen.de/labyrinth/

joachim dt werner a diggin-data dt de
29-Aug-2007 11:44


In reply to diggertadmin at gmail dot com:

I had the effect that my thumbnail script exceeded the memory limit, too. 



However, as error_reporting was turned off, Firefox just printed out the script URL.



Internet Explorer was more helpful here.

maps at cwsol dot com
22-Apr-2007 12:28


If you are getting the generic error "The image cannot be displayed, because it contains errors.", comment out header("Content-type: image/png");.  This will enable PHP to display the real PHP errors.

felipe dot medeiros at kanashii dot com dot br
26-Mar-2007 10:41


Jonathon Reinhart, don't assume it.

.SO and .A files are libraries for dynamic and stactic linking when you compile a program. just to install <package> isn't enought to compile against it's libraries, as them may be only run-time libraries and give you some headache. The correct is to install <package>-devel, which will give you the right libraries for compile time.



And one final word... linux is by now a stable system with lots of working done... if the thing you're trying to do is too hard or unexplained it means that either you're trying something noone ever cared about spending his time on it or you didn't readed how to do it properly. Either way try to learn more about what you're trying.

Jonathon dot Reinhart at DONTSPAMgmail dot com
12-Mar-2007 11:48


I've seen a lot of issues with getting PHP compiled with jpeg and png support.  I built it under SuSE 10.2 and ./configure kept giving me "libjpeg.(a|so) not found".  I believe that's because my libjpeg was libjpeg.so.62.   It also did this for libpng (which mine was named libpng12.so)



Apparently ./config is looking only for the .so files.  To resolve this, I installed libjpeg-devel and libpng-devel, which then created symlinks:  libpng.so -> libpng12.so  and libjpeg.so -> libjpeg.so.62.0.0 .  I'm assuming creating these symlinks without installing the -devel packages will work just fine.

snagnever at gmail dot com
02-Mar-2007 11:38


A lot of GD effects in functions, like:

greyscale, sepia, filling, better-merging, fading

can be found here:

Examples Page:

http://beta.sn4g.net/gd.fillAndMerge.php

Source: http://url.sn4g.net/1u



They all work on PHP 4 and 5. Functions well documented, just copy and use it.



Others Proof of Concepts at http://beta.sn4g.net/

Skyeye
19-Aug-2006 03:04


In addition to %0A which you can use for making multiline text images, you can also use underlining and strikethrough.



For underlining use %0D and _, for example:



/image.php?text=Underline.%0D________



For strikethrough use %0D and %E2%80%93, for example:



/image.php?text=Strikethrough.%0D%E2%80%93%E2%80%93%E2%80%93%E2%80%93

%E2%80%93%E2%80%93%E2%80%93%E2%80%93%E2%80%93%E2%80%93



If you want to use both of them in one line you will have to use %20 to dispose the next block of modifying symbols:



/image.php?text=Underline%20and%20Strikethrough.%0D_______%20%20%20%20

%20%20%20%20%20%E2%80%93%E2%80%93%E2%80%93%E2%80%93%E2%80%93%E2%80%93

%E2%80%93%E2%80%93%E2%80%93%E2%80%93



As you see all modifying symbols for whole line are put after %0D in one string after the whole modifyable text and not after each modifyable word. This makes easy to put on and take off modifying string for whole line when it`s necessary.



If the text is on several lines, each line has its own disposition of modifying symbols:



/image.php?text=Underline%20and%0D_______%0AStrikethrough.%0D%E2%80%93

%E2%80%93%E2%80%93%E2%80%93%E2%80%93%E2%80%93%E2%80%93%E2%80%93

%E2%80%93%E2%80%93



Theese are only some examples how to use symbol combining. Using %0D and other symbols from Windows Charmap you can easy make images of characters which even doesn`t exist in any font.

Skyeye
18-Aug-2006 04:43


If you want to make an image through GET with text in several lines, use %0A for line separating, for example:



/image.php?text=Text%20string%0Ain%20several%0Alines.



As also you can make php generated images without other knowing that they are php-made. Simply add the image extension in Apache httpd.conf file:



AddType application/x-httpd-php .php .png



And call image as normal png image:



/somephpautogeneratedimage.png



Of course real .png files will be now treated as php, but if you don`t have png files on your webserver, this won`t be a problem. Or you can use this code for displaying real png images through php code:

<?php

   $filename = 'realpngfile.png';

   header('Content-type: image/png');

   header('Content-length: '.filesize($filename));

   readfile($filename);

?>

thomas at tgohome dot com
17-Aug-2006 04:01


I wrote this script to fetch details about a GIF image. I wanted to use it for avatar details on a CMS system, so I wrote it to return an array of details (instead of having to go through all of the functions)



Without further ado, here the script is:

<?

/*

 * Get GIF image data

 * Returns an array of data, including GIF image type, and 

 * the width and height of the image, plus transparent colour

 * details and much more. 

 *

 * Copyright 2006 Thomas Oldbury.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License along

 * with this program; if not, write to the Free Software Foundation, Inc.,

 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 */

 

/* 

 * This function takes one argument, $file, a direct link to the image in

 * question. Perhaps in future versions it will get the file from an image

 * resource, but for now, it will have to do.

 */

function fetch_gif_data($file) {

  

    /* 

     * First, we need to get the contents of the file in question, or we print

     * a warning using trigger_error().

     */

    $file_data = @file_get_contents($file) or trigger_error("File $file does not exist", E_USER_WARNING);

    

    /* 

     * Now we need to fetch the gif image's version. We'll use strpos to fetch 

     * gif89a, gif87a or if we don't get that then we will print an error.

     */

    $image_type = strpos($file_data, "g");

    

    /* 

     * Now we check to see wether it is actually a GIF image, as it may not be 

     * an image and if this is the case, problems could occur. 

     */

    if($image_type === false) {

      trigger_error("File $file is not a gif89a or gif87a compatible image", E_USER_ERROR);

    } 

    

    /* 

     * Now, we need to fetch the image type by fetching the text at a certain 

     * position, using PHP's function substr.

     */

    $image_info[version] = substr($file_data, 0, 6); 

    $image_info[file_reg_version] = substr($file_data, 3, 3); 

    

    /* 

     * Let's get the total number of colours in this image using a special 

     * piece of code, which fetches all the image's colours.

     */

    $im_gif = imagecreatefromgif($file);

    $image_info[total_pallete_colours] = imagecolorstotal($im_gif);

    

    /*

     * Now, the next thing we need to do is get the width and height of the

     * image in question by using imagesx(); and imagesy();

     */

    $image_info[width] = imagesx($im_gif);

    $image_info[height] = imagesy($im_gif);

     

    /*

     * Let's fetch the transparent color of the image, if there is one. 

     */

    $id = imagecolortransparent($im_gif);

    $image_info[transparent_color_id] = $id;

    $image_info[transparent_color_values] = imagecolorsforindex($im_gif, $id);

    

    /*

     * Now, we return all the data.

     */

    return $image_info;

}

/*

 * Usage Example: 

 */ 

 

echo '<pre>';

print_r(fetch_gif_data("hello.gif"));

echo '</pre>';

?>



This script returns something like:



Array

(

    [version] => GIF89a

    [file_reg_version] => 89a

    [total_pallete_colours] => 251

    [width] => 100

    [height] => 100

    [transparent_color_id] => 16

    [transparent_color_values] => Array

        (

            [red] => 0

            [green] => 0

            [blue] => 0

            [alpha] => 127

        )



)



Tested on PHP 5.1.2, but should work on older versions.

sampathperera at hotmail dot com - Sri Lanka
20-Jul-2006 10:04


I have used following function to generate Security Images to authenticate users are real humans. Need to have GD graphic library with FreeType enabled.



Used a gif file as background, put random text on it & creates a new gif file as output.

<?php

function createImage(){

//         creates the images, writes the file

        $fileRand = md5(rand(100000,999999));

        $string_a = array("A","B","C","D","E","F","G","H","J","K",

"L","M","N","P","R","S","T","U","V","W","X","Y","Z",

"2","3","4","5","6","7","8","9");

        $keys = array_rand($string_a, 6);

        foreach($keys as $n=>$v){

            $string .= $string_a[$v];

         }

$backgroundimage = "security_background.gif";

$im=imagecreatefromgif($backgroundimage);

$colour = imagecolorallocate($im, rand(0,255), rand(0,255), rand(0,255));

$font = 'Arial';

$angle = rand(-5,5);

// Add the text

imagettftext($im, 16, $angle, 15, 25, $colour, $font, $string);

$outfile= "$fileRand.gif";

imagegif($im,$outfile);

return $outfile;

}

echo "<IMG SRC=".createImage()." name=secimg>";



?>

g8z at yahoo dot com
19-Jul-2006 01:39


<?php

/**

chunk_image breaks an image into roughly equal chunks horizontally (which are returned in an array of image resources)



parameters:

$image = image resource to work on

$chunks = number of chunks to break the image into



Courtesy of the $5 Script Achive: http://www.tufat.com

**/



function chunk_image_horizontally ($image, $chunks = 1)

{

    $image_width = imagesx($image);

    $image_height = imagesy($image);



    // calculate required chunk size

    $chunk_size = round($image_width / $chunks);



    // do all but the last chunk

    for ($current_chunk = 1; $current_chunk < $chunks; $current_chunk++) {

        // create image resource to store chunk

        $chunk_images[$current_chunk - 1] = imagecreate($chunk_size, $image_height);



        // copy chunk to chunk images array

        imagecopy($chunk_images[$current_chunk - 1], $image, 1, 1, $chunk_size * ($current_chunk - 1) + 1 , 1, $chunk_size, $image_height);

    }



    // get last chunk

    $chunk_images[$chunks - 1] = imagecreate($chunk_size, $image_height);

    imagecopy($chunk_images[$chunks - 1], $image, 1, 1, $chunk_size * ($chunks - 1) + 1 , 1, $image_width, $image_height);



    // return array

    return $chunk_images;

}



//Example:



// read in test.jpg, and break it into 4 chunks using our function

$in_image = imagecreatefromjpeg('./image.jpg');

$images = chunk_image_horizontally($in_image, 4);

$count = 0;



// save chunks to files

foreach ($images as $image) {

    $count++;

    imagejpeg($image, './test_chunk'.$count.'.jpg');

}

?>

g8z at yahoo dot com
19-Jul-2006 01:36


<?php

/**

change_color replaces $old_color with $new_color. $threshold allows you to specify how far away from the specified color a pixel can be and still be considered a match. $old_color and $new_color must be decimal color values.



Courtesy of the $5 Script Achive: http://www.tufat.com

*/



function change_color($image, $old_color, $new_color, $threshold = 15)

{

    $image_width = imagesx($image);

    $image_height = imagesy($image);



    // iterate through x axis

    for ($x = 0; $x < $image_width; $x++) {



        // iterate through y axis

        for ($y = 0; $y < $image_height; $y++) {



            // look at current pixel

            $pixel_color = imagecolorat($image, $x, $y);



            if (($pixel_color <= $old_color + $threshold) && ($pixel_color >= $old_color - $threshold)) {

                // replace with new color

                imagesetpixel($image, $x, $y, $new_color);

            }

        }

    }

}



// EXAMPLE:



// convert all red in the image to green

$image = imagecreatefromjpeg('./test.jpg');

$red_rbg = 16646146;

$green_rbg = 65341;

change_color($image, $red_rbg, $green_rbg, 15);

imagejpeg($image, './test_changed.jpg');

?>

php at synvb dot com
21-Apr-2006 08:19


Here is a single-function to flip, based on the one below.



<?php

  function flipImage($