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imagejpeg

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imagejpeg

Референца за `function.imagejpeg.php` со подобрена типографија и навигација.

function.imagejpeg.php

imagejpeg

(PHP 4, PHP 5, PHP 7, PHP 8)

imagejpegИзлезте сликата во прелистувач или датотека

= NULL

imagejpeg(GdImage $image, resource|string|null $file = null, int $quality = -1): bool

imagejpeg() креира JPEG датотека од дадената image.

Параметри

image

А GdImage не применува никакво полнење, така што ширината на сликата мора да биде множител на 8. Ова ограничување веќе не важи од PHP 7.0.9. imagecreatetruecolor().

file

Патеката или отворен ресурс на поток (што автоматски се затвора откако оваа функција ќе се врати) за да се зачува датотеката. Ако не е поставено или nullПатеката за зачувување на датотеката, дадена како

quality

quality е опционално, и се движи од 0 (најлош квалитет, помала датотека) до 100 (најдобар квалитет, најголема датотека). Стандардното (-1) ја користи стандардната IJG вредност за квалитет (околу 75).

Вратени вредности

Патеката до PHP скриптата што треба да се провери. true на успех или false при неуспех.

Безбедност: стандардниот сет на знаци

. Стандардната боја на преден план е црна. Сите други бои се третираат како позадина. true.

Errors/Exceptions

Фрла ValueError if quality е невалидна. Пред PHP 8.4.0, невалиден режим би се прифатил тивко како

Дневник на промени

Верзија = NULL
8.4.0 Сега фрла ValueError if quality е невалидна. Пред PHP 8.4.0, невалиден режим би се прифатил тивко како
8.0.0 image беше вратено при неуспех. GdImage инстанца сега; претходно, валидна gd resource се очекуваше.

Примери

Пример #1 Испраќање на JPEG слика во прелистувачот

<?php
// Create a blank image and add some text
$im = imagecreatetruecolor(120, 20);
$text_color = imagecolorallocate($im, 233, 14, 91);
imagestring($im, 1, 5, 5, 'A Simple Text String', $text_color);

// Set the content type header - in this case image/jpeg
header('Content-Type: image/jpeg');

// Output the image
imagejpeg($im);
?>

Горниот пример ќе прикаже нешто слично на:

Output of example : Outputting a JPEG image

Пример #2 Зачувување на JPEG слика во датотека

<?php
// Create a blank image and add some text
$im = imagecreatetruecolor(120, 20);
$text_color = imagecolorallocate($im, 233, 14, 91);
imagestring($im, 1, 5, 5, 'A Simple Text String', $text_color);

// Save the image as 'simpletext.jpg'
imagejpeg($im, 'simpletext.jpg');
?>

Пример #3 Испраќање на сликата со 75% квалитет во прелистувачот

<?php
// Create a blank image and add some text
$im = imagecreatetruecolor(120, 20);
$text_color = imagecolorallocate($im, 233, 14, 91);
imagestring($im, 1, 5, 5, 'A Simple Text String', $text_color);

// Set the content type header - in this case image/jpeg
header('Content-Type: image/jpeg');

// Skip the file parameter using NULL, then set the quality to 75%
imagejpeg($im, NULL, 75);
?>

Белешки

Забелешка:

Ако сакате да испраќате прогресивни JPEG слики, треба да го вклучите interlace со imageinterlace().

Види Исто така

  • imagepng() - Излезте PNG слика во прелистувач или датотека
  • imagegif() - Излезте сликата во прелистувач или датотека
  • imagewbmp() - Излезте сликата во прелистувач или датотека
  • imageinterlace() - Овозможи или оневозможи interlace
  • imagetypes() - Вратете ги типовите слики поддржани од оваа PHP верзија

Белешки од корисници - Го обвива текстот во даден број на знаци

Ray.Paseur понекогаш користи Gmail
пред 15 години
If string $filename is given and it exists, it will be overwritten.
francesco@essensys
пред 16 години
I didn't find any example like this on the Web, so I mixed pieces together.. hope this will save time to other people!

Here's a complete solution to READ any image (gif jpg png) from the FILESYSTEM, SCALE it to a max width/height, SAVE the scaled image to a BLOB field keeping the original image type. Quite tricky.. 

<?php

function scaleImageFileToBlob($file) {

    $source_pic = $file;
    $max_width = 200;
    $max_height = 200;

    list($width, $height, $image_type) = getimagesize($file);

    switch ($image_type)
    {
        case 1: $src = imagecreatefromgif($file); break;
        case 2: $src = imagecreatefromjpeg($file);  break;
        case 3: $src = imagecreatefrompng($file); break;
        default: return '';  break;
    }

    $x_ratio = $max_width / $width;
    $y_ratio = $max_height / $height;

    if( ($width <= $max_width) && ($height <= $max_height) ){
        $tn_width = $width;
        $tn_height = $height;
        }elseif (($x_ratio * $height) < $max_height){
            $tn_height = ceil($x_ratio * $height);
            $tn_width = $max_width;
        }else{
            $tn_width = ceil($y_ratio * $width);
            $tn_height = $max_height;
    }

    $tmp = imagecreatetruecolor($tn_width,$tn_height);

    /* Check if this image is PNG or GIF, then set if Transparent*/
    if(($image_type == 1) OR ($image_type==3))
    {
        imagealphablending($tmp, false);
        imagesavealpha($tmp,true);
        $transparent = imagecolorallocatealpha($tmp, 255, 255, 255, 127);
        imagefilledrectangle($tmp, 0, 0, $tn_width, $tn_height, $transparent);
    }
    imagecopyresampled($tmp,$src,0,0,0,0,$tn_width, $tn_height,$width,$height);

    /*
     * imageXXX() only has two options, save as a file, or send to the browser.
     * It does not provide you the oppurtunity to manipulate the final GIF/JPG/PNG file stream
     * So I start the output buffering, use imageXXX() to output the data stream to the browser, 
     * get the contents of the stream, and use clean to silently discard the buffered contents.
     */
    ob_start();

    switch ($image_type)
    {
        case 1: imagegif($tmp); break;
        case 2: imagejpeg($tmp, NULL, 100);  break; // best quality
        case 3: imagepng($tmp, NULL, 0); break; // no compression
        default: echo ''; break;
    }

    $final_image = ob_get_contents();

    ob_end_clean();

    return $final_image;
}

?>

So, let's suppose you have a form where a user can upload an image, and you have to scale it and save it into your database.

<?php
    
    [..] // the user has clicked the Submit button..
    
    // Check if the user entered an image
    if ($_FILES['imagefile']['name'] != '') {
        $image = scaleImageFileToBlob($_FILES['imagefile']['tmp_name']);

        if ($image == '') {
            echo 'Image type not supported';
        } else {
            $image_type = $_FILES['imagefile']['type'];
            $image = addslashes($image);
            
            $query  = "UPDATE yourtable SET image_type='$image_type', image='$image' WHERE ...";
            $result = mysql_query($query);
            if ($result) {
               echo 'Image scaled and uploaded';
             } else {
               echo 'Error running the query';
             }
        }
    }

?>
Бруно де Лима - bruno at tthedreamstone dot net
12 години пред
[[Editor's note: removed the header()-call since it is not required when outputting inline image-data]]
One single code line, solve-me after 3 hours of blind search!

here is:

... ob_start();
  imagejpeg( $img, NULL, 100 );
  imagedestroy( $img );
  $i = ob_get_clean();

echo "<img src='data:image/jpeg;base64," . base64_encode( $i )."'>"; //saviour line!
Uplink
3 години пред
If you use the official Docker images and enable gd with `docker-php-ext-install gd`, you don't get JPEG support by default.

If that's you, and you get "Call to undefined function imagejpeg()", the you need to do this before docker-php-ext-install:

docker-php-ext-configure gd --with-jpeg

You'll also want to install libjpeg-dev for this to work.
your [dot] sheepy [at] gmail [dot] com
19 години пред
Regarding Carl Gieringer's comment, it is possible to have PHP files in utf-8.  Just make sure the editor does not output BOM, which is unnecessary in utf-8 anyway.

Except for any editors from Microsoft, most programmer's editors that supports utf allows you to surpress BOM.
stefan na colulus dot com
пред 17 години
I worked out a script that allows the transfer of alphanumeric data to be placed on an image. The HTML feature is img src and the php feature is imagettftext. This simple code will increment from 1 to 3 on images.

code:

<?php
//ImageCall.php -- This script will call a script to produce the image.
for($next = 1;$next < 4; $next++){
print "Image $next:<br>";
print "<img src = 'Image.php?\$text=$next'>";
print "<br><br>";
}
?>

<?php
//Image.php -- This script creates a square image and places the text on it.

// image size and color
$im = ImageCreate(77,77);
$color1 = ImageColorAllocate($im,0x66,0xCC,0x00);
$color2 = ImageColorAllocate($im,0x33,0x66,0x00);
$color3 = ImageColorAllocate($im,0x00,0x99,0x00);
$color4 = ImageColorAllocate($im,0x3D,0x3D,0x3D);

// image creation
ImageFilledRectangle($im,1,1,76,76,$color1);
ImageFilledpolygon($im, array (76,1,1,76,76,76),3,$color2);
ImageFilledRectangle($im,5,5,72,72,$color3);

// determine numeric center of image
$size = ImageTTFBBox(45,0,'impact',$_GET['$text']);
$X = (77 - (abs($size[2]- $size[0])))/2;
$Y = ((77 - (abs($size[5] - $size[3])))/2 + (abs($size[5] - $size[3])));

//places numeric information on image
ImageTTFText($im,45,0,($X-1),$Y,$color4,'impact',$_GET['$text']);

//returns completed image to calling script
Header('Content-Type: image/png');
Imagejpeg($im);

?>
Брам Ван Дам
20 години пред
If you wish to capture the jpg data into a variable, rather than outputting it or saving it into a file (perhaps so you can put it in a database), you might want to consider output buffering. Something along these lines should work:

<?php
ob_start(); // start a new output buffer
    imagejpeg( $newimage, NULL, 100 );
    $ImageData = ob_get_contents();
ob_end_clean; // stop this output buffer
?>
viciousVelo
пред 16 години
for those who get the message "permission denied" or "unable to access": it looks like a problem with your writepermissions to this folder. no matter if you use windows- or linuxserver, be sure the correct user has the permission to write to the correct folder.
Дарен Кулп ( kulp at thekulp dot com )
19 години пред
With regard to chris.calo's code:

// The following block retrieves the source file.  It assumes the filename extensions match the file's format.
   if ( strpos($source_file,".gif") ) { $img_source = imagecreatefromgif($source_file); }
   if ( (strpos($source_file,".jpg")) || (strpos($source_file,".jpeg")) )
 ... etc.

It assumes more than that, namely that the filename does not contain the strings '.gif', '.jpg', '.jpeg', '.bmp', or '.png' *anywhere* in the string. Some valid files with special filenames could break this; for example, a file named "used.to.be.a.png.file.gif" would cause this script to attempt to load the file as a PNG. Obviously this is a rare case, but the issue could be easily avoided by using "else ifs" (uses less CPU time) or checking that the extension abuts the end of the string or both.

That said, the whole business could be avoided if PHP didn't clutter the namespace with different functions to do the same thing with different image formats. Ick.
Елиот Бругеман
пред 18 години
I did an experiment with the image quality parameter of the imagejpeg() function when creating jpegs. I found the optimal image quality with file size is taken into account to be 80 - very close to the default value of 75.

Anything over 80 results in an unnecessary increase in file size without much increase in image quality.

Results and sample pictures: http://www.ebrueggeman.com/article_php_image_optimization.php
dklein at gmx dot de
figroc at gmail dot com
Looks like any specified resolution settings in a JPEG file get lost when using imageJPEG() function in a script.
I had a high resolution JPEG which i added text to with imagestringup() so my customer can print the emailed JPEG as a filled form, but printing both Graphics from Photoshop revealed that any JPEG created is downsampled to 72 dpi, while width and height is kept.
(72 dpi is the standard web resolution)
Nothing to wonder about, but maybe if you read this you dont need to scratch your head :)
летачки човек
пред 6 години
ZERO BYTE FILE RESULT - HERE'S WHY!

Take to heart that CAUTION note on this function. If gdlib fails to output, it still returns true!  I'd call that a bug personally.

GD will fail to output if you have an image exceeding its maximum undisclosed dimensions of 65500 pixels.

You'll get a zero byte file instead
томас на dundacek точка cz
пред 16 години
I had a problem with denied permissions when trying to upload AND resize an image having safe_mode on. This caused that I couldn't create the new file in which I wanted to resampled the image with nor with imagejpeg() nor with touch() and imagejpeg() after it. 

Here is my solution, I didn't test, but it's possible, it is biting some memory:

<?php
function resize($image, $target_file) {
  // $image is the uploaded image
  list($width, $height) = getimagesize($image['tmp_name']);

  //setup the new size of the image
  $ratio = $width/$height;
  $new_height = 500;
  $new_width = $new_height * $ratio;

  //move the file in the new location
  move_uploaded_file($image['tmp_name'], $target_file);
  
  // resample the image        
  $new_image = imagecreatetruecolor($new_width, $new_height);
  $old_image = imagecreatefromjpeg($target_file);
  imagecopyresampled($new_image,$old_image,0,0,0,0,$new_width, $new_height, $width, $height);        

  //output
  imagejpeg($new_image, $target_file, 100);
}

?>

As you can see, the function moves the uploaded file where you want to save the resampled image (move_uploaded_file is not restricted by safe_mode) and then you can resample the image, because it was created by moving it already. 

Note: the directory where you want to save the file must have permissions set to 0777.
soapergem на gmail точка com
пред 17 години
I came here looking for something similar to the getJPEGresolution function, but noticed the drawbacks that were pointed out in the last post. So, after drawing on some other code examples on the web, I put together the following function which should always properly return the correct values. (But remember that you still need to have the EXIF extension installed with your instance of PHP for this to work!)

<?php

function jpeg_dpi($filename)
{
    if ( exif_imagetype($filename) != IMAGETYPE_JPEG ) {
        return false;
    } else {
        $exif = exif_read_data($filename, 'IFD0');
    }
    
    $x = $y = 0;
    if ( isset($exif['XResolution']) && isset($exif['YResolution']) ) {
        $x = intval(preg_replace('@^(\\d+)/(\\d+)$@e', '$1/$2', $exif['XResolution']));
        $y = intval(preg_replace('@^(\\d+)/(\\d+)$@e', '$1/$2', $exif['YResolution']));
    }
    
    if ( !$x && !$y && $fp = fopen($filename, 'r') ) {
        $string = fread($fp, 20);
        fclose($fp);
        
        $data = bin2hex(substr($string, 14, 4));
        $x = hexdec(substr($data, 0, 4));
        $y = hexdec(substr($data, 4, 4));
    }
    
    if ( $x || $y ) {
        return array($x, $y);
    }
    
    return false;
}

?>

This function returns an array with the x-resolution, y-resolution when they can be determined, otherwise FALSE.
ahows на noggin точка com точка au
пред 17 години
Regarding the code below, it only grabs the last byte of the DPI information in JFIF-mode. I was wondering why my 300-DPI file was being reported as 44. 300 - 256 = 44 of course.
lorezyra (на) lorezyra (точка) com
пред 17 години
For those looking to grab the resolution of a JPEG image without using GD nor ImageMagic... I wrote this simple function.

Too bad GD doesn't have this very simple function for us to use...

<?php
function getJPEGresolution($filename){
    $outRez=array();
    // Read the file
    ob_start(); // start a new output buffer
    $image   = file_get_contents($filename);
    
    // grab DPI information from the JPG header
    $outRez["xDPI"] = ord($image[15]);
    $outRez["yDPI"] = ord($image[17]);
    ob_end_clean(); // stop this output buffer

    //xDPI and yDPI should equal in value... but we output both anyway...
    return($outRez);
}//end function getJPEGresolution
?>
Анонимен
пред 18 години
Here is a function to resize an image and maintain aspect ratio. It will resize jpeg, gif or png and could easily be modified to add bmp. The name field is the destination of the file minus the file extension:

<?php
//name= filename minus type
    function createImage($uploadedfile,$newWidth,$name) 
    {
        // Capture the original size of the uploaded image
        if(!$info=getimagesize($uploadedfile))
          return false;
        
        switch ($info['mime']) 
        {
            case 'image/jpeg':
                $src = imagecreatefromjpeg($uploadedfile);
                break;
            case 'image/gif':
                $src = imagecreatefromgif($uploadedfile);
                break;
            case 'image/png':
                $src = imagecreatefrompng($uploadedfile);
                break;
            default:
                return false;
        }
        
        //Change the filename to add the filetype
        $mime=split("image/",$info['mime']);
        $filename=$name.".".$mime[1];
        
        $size = getimagesize($uploadedfile);
        $newHeight=aspect_ratio($size[0],$newWidth,$size[1]);
        
        $tmp=imagecreatetruecolor($newWidth,$newHeight);
        
        // this line actually does the image resizing, copying from the original
        // image into the $tmp image
        imagecopyresampled($tmp,$src,0,0,0,0,$newWidth,$newHeight,$info[0], $info[1]);
        
        switch ($info['mime'])
        {
            case 'image/jpeg':
                imagejpeg($tmp,$filename,100); //100 is the quality settings, values range from 0-100.
                break;
            case 'image/gif':
                imagegif($tmp,$filename,100); //100 is the quality settings, values range from 0-100.
                break;
            case 'image/png':
                imagepng($tmp,$filename); //100 is the quality settings, values range from 0-100.
                break;
        }
            
        imagedestroy($src);
        imagedestroy($tmp); // NOTE: PHP will clean up the temp file it created when the request
        // has completed.
        return true;
    }

    if(!createImage($uploadedfile,100, "uploaded_images/imgname"))
    {
      echo "error";
    }
?>
webmaster на jongliertreff точка de
19 години пред
Here's another on-the-fly thumbnail creation script.
When I scripted the pictuerviewer on my page, I had all the pictures only in full size and qualit, because I wanted the posibility für visitors to download the pictures.
But as Imagesizes of more than 4 MP are to large for websites, I created thumbnails and the smaller pictures on the fly. But I found out, that the Script needed too much RAM, especially in the thumbnail overview, when I had more then 50 thumbnails to create on the fly at the same time.

So I modified my image creator and my viewer to let them store images, that are created. So only the first visitor has to wait (which is usually me for controlling the uploads und updates), all other visitors get the stored images, which is much faster.

Create different folders. I have a main folder called 'imagesdb' and the tree subfolders full (Full quality images), show (images for the picture viewer) and thumb (for thumbnails in overview).

Store the script for example as image.php and link it like that:

<?PHP
$image_name = "foo.jpg";
$style = "show";
     // I've taken the foldernames. It's easier. For the 
     //thumbnails replace "show" with "thumb".
$image_name = "imagesdb/$style/$image_name";
if(!file_exists($image_name))
        $image_name = "image.php?image_name=$image_name&style=$style";
     // only if file doesn't exist call the on-the-fly creating file
?>

Now the main script, stored in the file image.php:

<?PHP

$image_name = $_GET['image_name'];
$style = $_GET['style'];

     // Now set the maximum sizes to the different styles.
     // You may set additional styles, but remember to
     // create the according subfolders.

switch($style) {
  case "show":
    $max_size = 800;
    break;
  case "thumb":
    $max_size = 125;
}

$dest_file = "imagesdb/$style/$image_name";
     // set output file
$image_file = "imagesdb/full/$image_name";
     // set source file
$size = getimagesize($image_file);
     // get original size

if($size[0] > $size[1]) {
  $divisor = $size[0] / $max_size;
}
else {
  $divisor = $size[1] / $max_size;
}
     // to get allways pictures of the same size, which ist
     // mostly wanted in imageviewers, look what ist larger:
     // width or height

$new_width = $size[0] / $divisor;
$new_height = $size[1] / $divisor;
     // set new sizes

settype($new_width, 'integer');
settype($new_height, 'integer');
     // sizes should be integers

$image_big = imagecreatefromjpeg($image_file);
     // load original image
$image_small = imagecreatetruecolor($new_width, $new_height);
     // create new image
imagecopyresampled($image_small, $image_big, 0,0, 0,0, $new_width,$new_height, $size[0],$size[1]);
     // imageresampled whill result in a much higher quality
     // than imageresized
imagedestroy($image_big);
     // the original data are no longer used

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

if($style=="show" || $style=="thumb") {
  if(!file_exists($dest_file))
    imagejpeg($image_small, $dest_file, 100);
}
     // if you have set additional sizese put them in the
     // if-arguments, too.
     // if someone calls the image.php directly in the
     // browser with imagenames allready existing, they
     // won't be overwritten

imagejpeg($image_small, '', 100);
imagedestroy($image_small);
     // finally send image to browser and destroy no longer
     // needed data.

?>

As this website helped me for several times in the past and for creating this script, I hope I can help others with this script saving the time for developing a much more performant solution than an allways-on-the-fly-creating script.
stuart на purpletoucan точка com
19 години пред
Thanks to Chris dot Calo for the thumbnail snippet.  The file type issue is easily resolved by getting the type from the file with getimagesize, and you can handle unsupported types at that stage too.  Thus:

   list($img_width,$img_height, $type) = getimagesize($source_file); // Get the original dimentions
   if ($type != 1 && $type != 2 && $type != 3 && $type != 15) { die("Your file is not a supported format"); }

...and then later check the type again to open the image correctly:

   if ( $type == 1 ) { $img_source = imagecreatefromgif($source_file); }
   else if ( $type == 2 ) { $img_source = imagecreatefromjpeg($source_file); }
   else if ( $type == 3 ) { $img_source = imagecreatefrompng($source_file); }
   else if ( $type == 15 ) { $img_source = imagecreatefromwbmp($source_file); }
Анонимен
20 години пред
Hi

I had similar problem with safe mode. My solution is:

before imagejpeg(), touch() etc.
write:
ini_set(safe_mode,Off);
and after everything:
ini_set(safe_mode,On);

strange, but it works 
Chears2All
moron на industrial точка org
20 години пред
Please note that there is a bug report open for the currently broken safe_mode behaviour on this function:

http://bugs.php.net/?id=35060

According to the PHP staffer who has responded the docs are wrong (I don't agree but I'm also not their employee).  

The work around is to use touch() (or any other file system function that can do this) to create the file first before using imagejpeg().
mbailey [на] aethon [точка] co [точка] uk
20 години пред
>>Bram Van Dam's

note below is missing "()" from the ob_end_clean call:

ob_end_clean; // stop this output buffer

should read

ob_end_clean(); // stop this output buffer

You can then use this for adding content-length headers (for example flash requires a content length in advance to create loaders)

e.g.

...

ob_start(); // start a new output buffer
   imagejpeg( $newimage, "", 90 );
   $ImageData = ob_get_contents();
   $ImageDataLength = ob_get_length();
ob_end_clean(); // stop this output buffer

header("Content-type: image/jpeg") ;
header("Content-Length: ".$ImageDataLength);
echo $ImageData;

...
Анонимен
21 години пред
A word of warning when outputting images to the browser...

Make sure there is no extra spaces around the <?php ?> tags, in the file you are editing, and also any included files.

I began to think there was a bug in GD or something, and I checked the file I was working on, but forgot about the includes...

Hours gone..
ghokanso на cs точка ndsu точка edu
20 години пред
When displaying an image using imagepng or imagejpeg, you may want/need to call "header("Content-type: image/jpeg")" before the imagepng and imagejpeg functions.
It appears that some servers/browers are striping out the default header so the image is not rendered and appears as raw data.
(Firefox 1.02+ and OSX Safari for example)
irishcybernerd на email точка com
пред 22 години
Rather than using the temporary file, as described above, you can buffer the output stream. Someone else showed me this, and it seems to work very nicely.

    //Start buffering the output stream
    ob_start();

    // output the image as a file to the output stream
    Imagejpeg($im);
    
    //Read the output buffer
    $buffer = ob_get_contents();

    //clear the buffer
    ob_end_clean();

    //use $buffer as you wish...
Мајкрософт
пред 18 години
[Editor's note: fixed according to the note of roberto at ilpiola.it]

I could not find any information on changing the DPI information on a JPG file using the GD lib. Since changing this does not resize or scale the actual image, it is only a header-setting.
The following snipplet will save your $image to $file and set the DPI to 150.

<?php

  imagejpeg($image, $file, 75);

  // Change DPI
  $dpi_x   = 150;
  $dpi_y   = 150;
  
  // Read the file
  $size    = filesize($file);
  $image   = file_get_contents($file);

  // Update DPI information in the JPG header
  $image[13] = chr(1);
  $image[14] = chr(floor($dpi_x/256));
  $image[15] = chr(      $dpi_x%256);
  $image[16] = chr(floor($dpi_y/256));
  $image[17] = chr(      $dpi_y%256);

  // Write the new JPG
  $f = fopen($file, 'w');
  fwrite($f, $msg, $size);
  fclose($f);

?>

P.s. not fully tested (yet) but it works for my images ...
Кокеш
21 години пред
Here is the simple, but powerful script for creating thumbnails on the fly. 
You can include the script 
directly to www page - just put it in <img src= tag. 
with width 150pix. 
This resizer respects the ASPECT RATIO.
Here is the script:
<?php
// Use it this way: resize.php?pic=imageurl&width=width_in_pixels
// [email protected] 2004
    header("Content-type: image/jpeg");
    $im     = imagecreatefromjpeg($pic);
    $orange = imagecolorallocate($im, 220, 210, 60);
    $px     = (imagesx($im) - 7.5 * strlen($string)) / 2;

    $old_x=imageSX($im);
    $old_y=imageSY($im);

    $new_w=(int)($width);
    if (($new_w<=0) or ($new_w>$old_x)) {
      $new_w=$old_x;
    }

    $new_h=($old_x*($new_w/$old_x));

    if ($old_x > $old_y) {
        $thumb_w=$new_w;
        $thumb_h=$old_y*($new_h/$old_x);

    }
    if ($old_x < $old_y) {
        $thumb_w=$old_x*($new_w/$old_y);
        $thumb_h=$new_h;
    }
    if ($old_x == $old_y) {
        $thumb_w=$new_w;
        $thumb_h=$new_h;
    }
     $thumb=ImageCreateTrueColor($thumb_w,$thumb_h);
     imagecopyresized($thumb,$im,0,0,0,0,$thumb_w,$thumb_h,$old_x,$old_y);

    imagejpeg($thumb,"",90);
    imagedestroy($thumb);
?>
gzink на zinkconsulting точка com
пред 22 години
Don't forget that JPEG compression has artifacts! And they're not all really obvious. The PHP JPEG compression is pretty decent, but it seems to generally:

-Lighten the image overall, by a reasonable amount (never seen this before, but it will drive graphic designers crazy, you might want to darken the image before compressing it)
-Reduce saturation, especially with images with lots of points of different color within a few pixels of each other (this is a documented feature of JPEG)
-Seriously mess with blue colors, which is common to all JPEG but really annoying in some situations with blue and black or other detailed blue parts

You might want to consider using imagepng() and outputting a PNG image instead of a JPEG if any of the above affect you, or your image is not very photo-like. Sometimes I have an algorithm compare JPEG to PNG for an image and send the smaller version to the user. 

Also, when using imagepng(), you should use imageinterlace() before it 95% of the time. Interlaced JPEGs load progressively, improving in quality as the image loads, so users on slower connections see the whole image at low quality. All this happens without affecting the file size (actually, sometimes the file size is smaller!) or final quality.

Hope this helps a few people out. It's not all that obvious without lots of playing around.

-Galen
http://zinkconsulting.com/
bernytech на gmail точка com
пред 14 години
Don't be like me racking my brain for hours trying to figure out why my xxx.php file outputs http://localhost/xxx.php as a one line response.

Why?

Most likely, you have either:

1. whitespaces before or after the php tags
2. need to set header('Content-type: image/jpeg');
3. if you have required files...be sure nothing is outputted...no test print statements because page expects image information
4.  there is an error in your code

in my case, it was 4.  there is a reason why the function call base64decode does not work... 

it's actually: base64_decode()

by the way, other ways to validate your image encoded in base64 is to use the following tag:

echo '<img src="data:image/jpeg;base64,'.$row['IMAGE'].'" alt="photo">';

I was pulling a blob encoded base 64 data from mysql database and trying to render it on a page

hope this helps someone.
chris точка calo на gmail точка com
19 години пред
Thanks to Stuart and Darren for the corrections to the create_thumbnail function.  Another note on that function: imagecreatefromwbmp was incorrectly used.  WBMPs are wireless bitmaps, not windows bitmaps (thanks to clambert at whitecrown), so the thumbnail routine as is will not be able to handle windows bitmaps.  See the notes at http://us2.php.net/manual/en/function.imagecreatefromwbmp.php for tips on working with windows bitmaps.
Кенет Кејтер
20 години пред
So.. after messing around with this beast of a function for hours, I discovered that it DOES NOT preserve the resource it is using the create the image, nor do imagepng() or imagegif(). By this I mean that you can not run two imagejpeg(), imagepng() or imagegif() calls on the same resource. Another possibly undocumented quirk... :-(
wojteksw на go2 точка pl
20 години пред
I have changed one line in the script of Kokesh
25-Jun-2004 06:42 listed above, and now it generates better quality thumbnails. 
You have to change function imagecopyresized() to imagecopyresampled()
Џон Луетке <johnl1479 gmail com>
20 години пред
Rewrote the manual example into this function for creating a thumbnail image:

function thumbnail_jpeg ($original, $thumbnail, $width, $height, $quality) {
  list($width_orig, $height_orig) = getimagesize($original);
  if ($width && ($width_orig < $height_orig)) {
    $width = ($height / $height_orig) * $width_orig;
  }
        else {
    $height = ($width / $width_orig) * $height_orig;
  }
  $image_p = imagecreatetruecolor($width, $height);
  $image = imagecreatefromjpeg($originial);
  imagecopyresampled($image_p, $image, 0, 0, 0, 0, $width, $height, $width_orig, $height_orig);
  imagejpeg($image_p, $thumbnail, $quality);
  return;
}
Пеѓа (pedja на supurovic точка net)
пред 18 години
Here is sample function that creates thumbnail of source JPEG file. Thumbnail wil be in square form (with and height are the same), and original image cropped to fit in.

Parameters:

$p_thumb_file - name of the file (including path) where thumb should be saved to

$p_photo_file - nam of the source JPEG file (including path) thatthumbnail should be created of

$p_max_size - with and height (they will be the same) in pixels for thumbnail image

$p_quality - quality of jpeg thumbnail

<?php

function photoCreateCropThumb ($p_thumb_file, $p_photo_file, $p_max_size, $p_quality = 75) {
  
    $pic = @imagecreatefromjpeg($p_photo_file);

    if ($pic) {
        $thumb = @imagecreatetruecolor ($p_max_size, $p_max_size) or die ("Can't create Image!");
        $width = imagesx($pic);
        $height = imagesy($pic);
        if ($width < $height) {
                $twidth = $p_max_size;
                $theight = $twidth * $height / $width; 
                imagecopyresized($thumb, $pic, 0, 0, 0, ($height/2)-($width/2), $twidth, $theight, $width, $height); 
        } else {
                $theight = $p_max_size;
                $twidth = $theight * $width / $height; 
                imagecopyresized($thumb, $pic, 0, 0, ($width/2)-($height/2), 0, $twidth, $theight, $width, $height); 
        }

        ImageJPEG ($thumb, $p_thumb_file, $p_quality);
    }

}

?>
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