[RESOLVED] GD Library help needed

[Dolemite50]

Hi,

Well I just spen about 3 hours going through this board and Google but couldn't accomplish what I had hoped. I have paths to member's images stored in mysql. There are pages that show about 15 or so member's pictures so I would like to generate thumbs of the images on the fly to save on bandwidth. The only problem is that I couldn't seem to find a way to do any of the GD functions outside of the header. From what I could tell the header requires"("Content-type: image/jpeg");" ..but what good does that do me on an html page? I tried changing it to text/html but no go. Whenever I try to display the pic I get a gibberish string of characters.

If I use only the header and do "Select image from db where user id = '$userid',; and then send that variable through the code it displays fine. I'm unable to do any sort of a loop because from what I've read image/jpeg is only for one image.

I was able to use this code to display ONE image.

So is my line of thinking off here? Would it be ideal to pre-generate all of the thumbs and store them on the server? (And also figure out how to create them on the fly for new members,..) If so,.I would I use GD to take an entire folder on the server and generate thumbs into a seperate folder.

I would really like the option that I was trying to get rolling in action but it's not looking possible.

Any help>?

Thanks

<?php

# Constants 
define(IMAGE_BASE, 'http://www.mysite.com/pics'); 
define(MAX_WIDTH, 25); 
define(MAX_HEIGHT, 25); 
$bandid=$_GET['bandid'];
$getpic = "SELECT userid FROM users LIMIT 10";
$picresult = mysql_query($getpic, $conn) or die(mysql_error());
while($row9  = mysql_fetch_assoc($picresult)){		
$userid = $row9[userid ];
# Get image location 
$getpic = "SELECT image from user_table WHERE userid = '$userid'";
$picresult = mysql_query($getpic, $conn) or die(mysql_error());
$image  = mysql_result($picresult, 0);
$image_file = str_replace('..', '', $image); 
$image_path = IMAGE_BASE . "/$image_file"; 

# Load image 
$img = null; 
$ext = strtolower(end(explode('.', $image_path))); 
if ($ext == 'jpg' || $ext == 'jpeg') { 
    $img = @imagecreatefromjpeg($image_path); 
} else if ($ext == 'png') { 
    $img = @imagecreatefrompng($image_path); 
# Only if your version of GD includes GIF support 
} else if ($ext == 'gif') { 
    $img = @imagecreatefrompng($image_path); 
} 

# If an image was successfully loaded, test the image for size 
if ($img) { 

# Get image size and scale ratio 
$width = imagesx($img); 
$height = imagesy($img); 
$scale = min(MAX_WIDTH/$width, MAX_HEIGHT/$height); 
//echo "Width is $width and height is $height<br>";
# If the image is larger than the max shrink it 
if ($scale < 1) { 
    $new_width = floor($scale*$width); 
    $new_height = floor($scale*$height); 

    # Create a new temporary image 
    $tmp_img = imagecreatetruecolor($new_width, $new_height); 

    # Copy and resize old image into new image 
    imagecopyresized($tmp_img, $img, 0, 0, 0, 0, 
                     $new_width, $new_height, $width, $height); 
    imagedestroy($img); 
    $img = $tmp_img; 
} 
} 

# Create error image if necessary 
if (!$img) { 
    $img = imagecreate(MAX_WIDTH, MAX_HEIGHT); 
    imagecolorallocate($img,0,0,0); 
    $c = imagecolorallocate($img,70,70,70); 
    imageline($img,0,0,MAX_WIDTH,MAX_HEIGHT,$c2); 
    imageline($img,MAX_WIDTH,0,0,MAX_HEIGHT,$c2); 
} 

# Display the image 
//header("Content-type: image/jpeg"); 
imagejpeg($img);
}
?> 

[Weedpacket]

Your given code would be a separate script from that generating the HTML page. The URL that calls it would go in the <img> tag's src= attribute. Obviously it would only generate the one image (the one that goes in that <img> tag) so it would need to know which image. Some unique identifier ($userid probably) would have to be included in the URL, and hence obtained by the script via the $_GET array.

<img src="mugshots.php?id=42">

But if you want to save work, you should consider generating thumbnails when the originals are uploaded and save them for use later. Then the <img> tag can just refer to that saved file as normal, and you don't have to run all that code for every thumbnail every time anyone wants to see one.

[Dolemite50]

Thanks Weedpacket. 🙂

Wow, sorry about my grammar on the original post, I think it was about 4am at that point. I'm surprised you even got the gist of what I was trying to say.

Well it looks like the route to go is pre-generated thumbs. That being said; if I have images stored in a folder called pics, and I setup another folder called picthumbs; is there a simple GD script to run that will loop through all of the image paths in the DB and create thumbs with the same filename in the picthumbs folder?

Thanks again.

[Weedpacket]

Not purely GD, but you could use PHP's directory functions to go through the directory, and run each image file it finds through the thumbnail generator.

[Dolemite50]

Thanks again,

I've been struggling all day with this. What is the thumbnail generator? I've been all over this board and the manual, have tried about 10 different methods but to no avail. I can get this method to show a thumb, but I can't figure out how to move it to the subdirectory "thumbs". (chmod 777) It no longer gives errors but when I check the "thumbs" directory it is empty.

# Constants 
define(IMAGE_BASE, 'http://www.mysite.com/bandpics'); 
define(MAX_WIDTH, 60); 
define(MAX_HEIGHT, 60); 
$bandid=107;
# Get image location 
$getpic = "SELECT image from table WHERE bandid = '$bandid'";
$picresult = mysql_query($getpic, $conn) or die(mysql_error());
$image  = mysql_result($picresult, 0);
$image_file = str_replace('..', '', $image); 
$image_path = "bandpics/$image_file"; 
$thumb_path = "bandpics/thumbs/$image"; 
# Load image 
$img = null; 
$ext = strtolower(end(explode('.', $image_path))); 
if ($ext == 'jpg' || $ext == 'jpeg') { 
    $img = @imagecreatefromjpeg($image_path); 
} else if ($ext == 'png') { 
    $img = @imagecreatefrompng($image_path); 
# Only if your version of GD includes GIF support 
} else if ($ext == 'gif') { 
    $img = @imagecreatefrompng($image_path); 
} 

# If an image was successfully loaded, test the image for size 
if ($img) { 

# Get image size and scale ratio 
$width = imagesx($img); 
$height = imagesy($img); 
$scale = min(MAX_WIDTH/$width, MAX_HEIGHT/$height); 
//echo "Width is $width and height is $height<br>";
# If the image is larger than the max shrink it 
if ($scale < 1) { 
    $new_width = floor($scale*$width); 
    $new_height = floor($scale*$height); 

    # Create a new temporary image 
    $tmp_img = imagecreatetruecolor($new_width, $new_height); 

    # Copy and resize old image into new image 
    imagecopyresized($tmp_img, $img, 0, 0, 0, 0, 
                     $new_width, $new_height, $width, $height); 
    imagedestroy($img); 
    $img = $tmp_img; 
} 
} 

# Create error image if necessary 
if (!$img) { 
    $img = imagecreate(MAX_WIDTH, MAX_HEIGHT); 
    imagecolorallocate($img,0,0,0); 
    $c = imagecolorallocate($img,70,70,70); 
    imageline($img,0,0,MAX_WIDTH,MAX_HEIGHT,$c2); 
    imageline($img,MAX_WIDTH,0,0,MAX_HEIGHT,$c2); 
} 
//echo"$img<br>$thumb_path";
//if (!copy($img, $thumb_path)) {
  // echo "failed to copy $file...\n";
//}
# Display the image 
//header("Content-type: image/jpeg"); 
//imagejpeg($img);
imagejpeg($img, "$thumb_path"); 

I found your responses on a lot of the GD related topics I've been through today so I know I'm in good hands. Keep in mind that I'm still a noob, so if you do have any suggestions be sure to use lame-man terms for me. 🙁

Thanks.

[Dolemite50]

oops!

Sorry WP, I stand corrected, it wasn't showing in the thumbs folder when I reurned to it but it did after I refreshed it. So will this method be OK to use in a loop like this?

$getpic = "SELECT image from table WHERE bandid <10";
$picresult = mysql_query($getpic, $conn) or die(mysql_error());
while($row9 = mysql_fetch_assoc($picresult)){
$image = $row9['image'];

[Dolemite50]

Well it seems to be working except the GIF's are coming out all black. I figured it must have been because at the end it said imagejpeg(
so I changed it to this:

if ($ext == 'jpg' || $ext == 'jpeg') { 
imagejpeg($img, $thumb_path);  

} else if ($ext == 'png') { 
imagepng($img, $thumb_path);  
# Only if your version of GD includes GIF support 
} else if ($ext == 'gif') { 
imagegif($img, $thumb_path); 
} 

but they are still black.

Any ideas?

(The GD library is new enough to support Gif)

[Dolemite50]

Ahah!

Criminy, I figured it out; check out this line straight from the tutorial:
} else if ($ext == 'gif') {
$img = @imagecreatefrompng($image_path);
}

[Weedpacket]

Gee, it's almost like you don't need me anymore 😉