exif_thumbnail

(PHP 4 >= 4.2.0, PHP 5)

exif_thumbnail — Récupère la miniature d'une image TIFF ou JPEG

Description

string exif_thumbnail ( string $filename [, int &$width [, int &$height [, int &$imagetype ]]] )

exif_thumbnail() lit la miniature de l'image TIFF ou JPEG dans le fichier filename .

Si vous voulez afficher des miniatures avec cette fonction, vous devez envoyer le bon type MIME avec la fonction header().

Il est possible que la fonction exif_thumbnail() n'arrive pas à créer l'image mais peut déterminer sa taille. Dans ce cas, la fonction retourne FALSE mais les paramètres width et height sont définis.

Liste de paramètres

filename: Le nom du fichier image à lire. Cette image contient une miniature.
width: La largeur retournée de la miniature retournée.
height: La hauteur retournée de la miniature retournée.
imagetype: Le type de l'image retourné de la miniature retournée. Peut être soit TIFF, soit JPEG.

Valeurs de retour

Retourne la miniature embarquée ou FALSE si l'image ne contient pas de miniature.

Historique

Version	Description
4.3.0	Les paramètres optionnels `width` , `height` et `imagetype` deviennent disponibles.
4.3.0	Les miniatures peuvent être retournées dans le format TIFF.

Exemples

Exemple #1 Exemple avec exif_thumbnail()


<?php
if (array_key_exists('file', $_REQUEST)) {
    $image = exif_thumbnail($_REQUEST['file'], $width, $height, $type);
} else {
    $image = false;
}
if ($image!==false) {
    header('Content-type: ' .image_type_to_mime_type($type));
    echo $image;
    exit;
} else {
    // aucune miniature de disponible, traitement de l'erreur ici
    echo 'No thumbnail available';
}
?>

Voir aussi

read_exif_data

exif_tagname

Last updated: Fri, 10 Oct 2008

add a note User Contributed Notes
exif_thumbnail

thrustvector at 'gee'mail dot com
29-Jul-2008 10:40


If you've edited the image with image editing software and it no longer contains an exif thumbnail, I've created a script that will add one back into it, using the "PHP Exif Library": http://pel.sourceforge.net/index.php



<?php

require_once('../PEL/PelJpeg.php');

require_once('../PEL/PelIfd.php');

$fullpath = 'images/DSC_0013c.JPG';  # path of source image (does not contain an exif thumbnail)

      

$jpeg = new PelJpeg($fullpath);

 $exif = $jpeg->getExif();

 $tiff = $exif->getTiff();

 $ifd0 = $tiff->getIfd();        # need this so that we can later link it to the new IFD 



 $ifd1 = $ifd0->getNextIfd();

if (!$ifd1) {        # Only create thumbnail if one doesn't exist (i.e. there is no IFD1)

    $ifd1 = new PelIfd(1);

    $ifd0->setNextIfd($ifd1); # point ifd0 to the new ifd1 (or else ifd1 will not be read)



    $original = ImageCreateFromString($jpeg->getBytes()); # create image resource of original

    $orig_w=imagesx($original);

    $orig_h=imagesy($original);

    $wmax = 160;

    $hmax = 120;



    if ($orig_w>$wmax || $orig_h>$hmax) {

        $thumb_w=$wmax;

        $thumb_h=$hmax;

        if ($thumb_w/$orig_w*$orig_h>$thumb_h)

            $thumb_w=round($thumb_h*$orig_w/$orig_h); # maintain aspect ratio

        else

            $thumb_h=round($thumb_w*$orig_h/$orig_w);

    }

    else { # only set the thumb's size if the original is larger than 'wmax'x'hmax'

        $thumb_w=$orig_w;

        $thumb_h=$orig_h;

    }



        # create image resource with thumbnail sizing

    $thumb=imagecreatetruecolor($thumb_w,$thumb_h); 

        ## Resize original and copy to the blank thumb resource

    imagecopyresampled($thumb,$original,

                               0,0,0,0,$thumb_w,$thumb_h,$orig_w,$orig_h);



        # start writing output to buffer

    ob_start();        

        # outputs thumb resource contents to buffer

    ImageJpeg($thumb);    

        # create PelDataWindow from buffer thumb contents (and end output to buffer)

    $window = new PelDataWindow(ob_get_clean()); 



    if ($window) {    



        $ifd1->setThumbnail($window); # set window data as thumbnail in ifd1

        $outpath = $fullpath; # overwrite original jpg file

        file_put_contents($outpath, $jpeg->getBytes()); # write everything to output filename

            # Show thumbnail in file:

        echo '<img src="thumb_exif.php?image='.$outpath.'" border=0 alt="If you see this, it did not work"><br>';



        

    }

}

else {

    echo 'ifd1 already exists! (IFD1 is where the thumbnail is stored)<br>';

}

?>

<?php # This is the code in thumb_exif.php :

        $imgdat = exif_thumbnail($_REQUEST['image'], $width, $height, $type);

        header('Content-type: ' . image_type_to_mime_type($type));

        echo($imgdat);

?>



If you have a lot of such files, you can easily make a script that searches them out and adds thumbnails to their exif.

Miguel Vitorino
08-Oct-2007 03:37


use this if you want to embed a thumbnail directly on the HTML page without writing it first to a file:



<?php

$image = exif_thumbnail($file, $width, $height, $type);



echo "<img  width='$width' height='$height' src='data:image/gif;base64,".base64_encode($image)."'>";

?>

05-Jan-2007 03:23


If you want to convert from TIFF to JPG you can use ImageMagick if it is installed in your server.



<?php

$exec = 'convert /path/to/file.tiff /path/to/file.jpg 2>&1';

@exec($exec, $exec_output, $exec_retval);



//possible error

print_r($exec_output)

?>

hanspeter dot debets at dendrite dot com
14-Jan-2005 03:35


Great that the thumbnail can be in TIFF format (f.i. Kodak cameras have embedded thumbnail in TIFF) BUT I have not been able to show TIFF as an embedded image in HTML (using the <IMG...> tag). There seems to be no function in PHP to change TIFF to, lets say, JPG. (imagecreatefromstring gives a 'unknown datatype' error for the TIFF stream. So below sample works great for JPEG embedded thumbnail, but not for TIFF embedded (but then, maybe I did something wrong?):



test_exif.php:



<HTML>

<HEAD>

    <TITLE>Test EXIF Read  </TITLE>

</HEAD>

<BODY>

<?php

$image='P0000614.JPG';

echo("<B>". $image. "</B>:<BR><BR>\n");



$exif = exif_read_data($image, 'ANY_TAG',true);

if (!$exif===false)

{

    echo("Image contains headers<br><br>");

    echo("<A href=showthumb.php?image=" . $image ."> <IMG border=0 src=showthumb.php?image=" . $image ."></A><BR><BR>");



    foreach ($exif as $key => $section) 

    {

        foreach ($section as $name => $val) 

        {

            echo "$key.$name: $val<br>\n";

        }

    }

}

else

{

    echo("Sorry, image <B>".$image . "</B> does not contain (readable) EXIF data.");

}

?>

</BODY>

</HTML>



showthumb.php:



<?php

$imgdat = exif_thumbnail($_REQUEST['image'],$width, $height, $type);

header('Content-type: ' . image_type_to_mime_type($type));

echo($imgdat);

?>



When clicking on the <A> opens the TIFF image in the program that windows assigned to this type, but the JPEG opens in the browser.



I am using PHP 4.3.6 on windows iis 4 (yeah, I know.....)

Eric
14-Jun-2004 04:05


This will allow you to manipulate the thumbnail image ($imgJpeg) using the various gd commands:



<?php

  if (($imgJpeg = exif_thumbnail($strImagePath)) === false)

    print "No Thumbnail!";

  else

    $imgJpeg = imageCreateFromString($imgJpeg);

?>

neothermic at ya[]o dot com ADD ho IN GAP
27-May-2004 07:01


You can use the EXIF thumbnail function to extract the thumnails for use in an image gallery. I've found this to be faster than using other GD functions to convert the image to a smaller one then save it.



Here is the code I use to generate thumbnails. Remember, this is more of a utility script, although its simple to modifiy it for use...



<?PHP

set_time_limit(0); //use this to make sure the script doesn't time out on large number of images.

//error_reporting(E_NONE); //use this to disable errors in a production script



function getmicrotime() {

    $temparray=split(" ",microtime());

    $returntime=$temparray[0]+$temparray[1];

    return $returntime;

} 



//lets make it slightly proper HTML. not valid, but can be changed quickly to be

echo "<html>

<head><title>Processing...</title></head>

<body>";



$maindir = "." ; //change this to what ever directory needs scanning

$mydir = opendir($maindir) ;

$starttime=getmicrotime(); 

$i = 0; //set the count of images processed to 0

while($fn = readdir($mydir)) //scan through the whole directory

    {//open while 



        $startimagetime = getmicrotime();

        $ext = strtolower(substr($fn,strlen($fn)-3)); //get the extension of an image

        if ($ext == "jpg") { 

            $i++; //increase the number of images processed

            echo $fn ." is being processed....<br>";

            flush(); //needed to display each image progress

            



            $image = exif_thumbnail($fn, $width, $height, $type);



            if ($image!==false) {

                    //if there is a good enough thumbnail to use, we have it here.

                    //extract it and put it in the file, call it [original image name].thumb.jpg

                 $handle = fopen ($fn.".thumb.jpg", 'a');

                 //write the thumbnail image

                 fwrite($handle, $image);

            } else {

                 // no thumbnail available, handle the error here

                 echo "No thumbnail available for file ".$fn."<br>";

            }

        }

}

closedir($mydir); 

$endtime=getmicrotime(); 



echo "<br>All Images have been processed, script is finshed.<br>Total processing time: ";

print $endtime-$starttime;

echo "<br> Images processed: " .$i;

echo "</body>";

echo "</html>"



?>



Its a bit crude, I must admit, but it can easily be adapted to suit user.



NeoThermic

add a note

read_exif_data

exif_tagname

Last updated: Fri, 10 Oct 2008