Problems with new version of GD-libraries

[levihalvorsen]

Background:

My host has updated the GD-library to version GD 2.0.12 (earlier version was 1.6.2 or 1.8).

Phpinfo:

PHP Version 4.3.2
GD Support enabled

GD Version bundled (2.0.12 compatible)

GIF Read Support enabled

JPG Support enabled

PNG Support enabled

WBMP Support enabled

XBM Support enabled

The problem:

With the older version of GD, i was able to upload images, making thumbs of all the pictures

(JPEG) and link the thumbs to the mainpicture.
This still works, but THE COLORS OF THE THUMB BECOME GREY. You can still see what the thumbs

are showing, but with a grey "layer" over...

The code:

In my mainfile:

makeThumb( $newphoto[ $i ], "{$IMAGE_DIR}/thumb/{$photoid}.jpg" );

The function itself:

---

function makeThumb( $scrFile, $dstFile, $dstW=120, $dstH=100 )
{
	$im = ImageCreateFromJPEG( $scrFile );
	$srcW = ImageSX( $im );
	$srcH = ImageSY( $im );
	$ni = ImageCreate( $dstW, $dstH );
	ImageCopyResized( $ni, $im, 0, 0, 0, 0, $dstW, $dstH, $srcW, $srcH );
	ImageJPEG( $ni, $dstFile );
}

---

Can someone help me??

Levi

[Weedpacket]

This is a fairly common problem with JPEGs. The problem is that JPEG is a truecolour image format, and the images created by GD 1.8 are all palette-based - limited to 256 colours. When you use [man]imagecreate[/man] you create a palette-based image, and copying truecolour images into one of those means GD has to guess at a palette and then map all the colours in the image to use that palette. For some reason, GD 2 is not as good at this as 1.8; but that's okay, because GD 2 allows you to create truecolour images using [man]imagecreatetruecolor[/man], which means that there is no such mapping needed, and the colours remain intact.

So, basically, replace the imagecreate() calls with imagecreatetruecolor() and the deal with the thumbnails will be fixed. In fact, the quality will improve. In fact, the quality will improve even further if you also replace [man]imagecopyresized[/man] with [man]imagecopyresampled[/man].

[levihalvorsen]

Thanks!

It worked excellent!!!
That was totally awesome!!!

😃

By the way, do you, or anybody else, how to make changes to the script above, so that the thumb will be maximum a spesial width (as above) but so that the hight will be resized the same prosentage... (so the picture is not draaagged in any direction)?

Levi

[jpmoriarty]

this is the resize section of what i use - you should be able to tweak it fairly easily to fit in with what you have already.

      $size = GetImageSize($file);
      $width = $size[0];
      $height = $size[1];

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

  if ( ($width <= $max_width) && ($height <= $max_height) ) {
    $tn_width = $width;
    $tn_height = $height;
  }
  else if (($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;
  }

  $src = ImageCreateFromJpeg($file);
  $dst = ImageCreate($tn_width,$tn_height);
  ImageCopyResized($dst, $src, 0, 0, 0, 0,
      $tn_width,$tn_height,$width,$height);

[levihalvorsen]

I really appreciate your help on this matter...

The problem is that I'm a TOTALLY newbee to this php-thing... (You guys probably don't call it "this php-thing"... )

So, I know it is a lot to ask for, but is it possible for you to help me "adjust" your code to fit into mine. I have tried to, but I can't get it to work, as I want to.

I want the thumb to be 120 wide, and the hight adjusted to look like the original picture.

You see my original code above!

I would be veeeery thankful!

Levi