php Imagemagick jpg black background

Question

I have a php script to create jpg thumbnail of pdf as follows;

<?php
$file ="test.pdf";
$im = new imagick(realpath($file).'[0]');
$im->setImageFormat("jpg");
$im->resizeImage(200,200,1,0);
// start buffering
ob_start();
$thumbnail = $im->getImageBlob();
$contents =  ob_get_contents();
ob_end_clean();
echo "<img src='data:image/jpg;base64,".base64_encode($thumbnail)."' />";
?>

But the resulting jpg have black background instead of white.. How can I fix this??

A copy or a link to the jpg file in question would be helpful and also a screen shot of the resulting output. — Laurence Burke, May 23 '11 at 15:54
Laurence Burke: here is the resulting image http://i.imgur.com/jyQC6.jpg — Alfred, May 23 '11 at 16:09
whats your css styling like and could you link the original jpg??? — Laurence Burke, May 23 '11 at 16:22
@Laurence Burke, the above one is the original jpg file. I have no styling at all.. — Alfred, May 23 '11 at 16:32

Luke Vincent · Answer 1 · 2018-08-10T15:36:43.520

None of the previously posted answers worked for me however the below did:

$image = new Imagick;

$image->setResolution(300, 300);

$image->readImage("{$originalPath}[0]");

$image->setImageFormat('jpg');

$image->scaleImage(500, 500, true);

$image->setImageAlphaChannel(Imagick::VIRTUALPIXELMETHOD_WHITE);

As I'm using the Laravel framework I then take the converted image and store it using Laravels filesystem.

Storage::put($storePath, $image->getImageBlob());

Update: So I recently changed OS and whereas this previously worked on my Ubuntu machine on my Mac certain images were still coming out black.

I had to change the script to the below:

$image = new Imagick;

$image->setResolution(300, 300);

$image->setBackgroundColor('white');

$image->readImage("{$originalPath}[0]");

$image->setImageFormat('jpg');

$image->scaleImage(500, 500, true);

$image->mergeImageLayers(Imagick::LAYERMETHOD_FLATTEN);

$image->setImageAlphaChannel(Imagick::ALPHACHANNEL_REMOVE);

Seems important to set the background colour before reading in the image. I also flatten any possible layers and remove the alpha channel. I feel like I tried ALPHACHANNEL_REMOVE on my Ubuntu machine and it didn't work so hopefully between these answers readers can find something that works for them.

when multiple-page pdf uploads then only the first page it's working but not the other pages. — Y. Joy Ch. Singha, Feb 01 '23 at 07:22

score 1 · Accepted Answer · answered Apr 09 '12 at 16:46

1

I solved it by;

$im = new imagick(realpath($file).'[0]');
$im->setCompression(Imagick::COMPRESSION_JPEG);
$im->setCompressionQuality(100);
$im->setImageFormat("jpeg");
$im->writeImage("imagename.jpg");

answered Apr 09 '12 at 16:46

Alfred

21,058
61
167
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`setCompressionQuality` not actualy working in this situation. For change quality use `setImageCompressionQuality` – vatavale Feb 24 '18 at 19:06

score 1 · Answer 3 · answered Sep 07 '12 at 09:39

1

Simply adding this prevents the JPG to be created with a black background

-alpha off

answered Sep 07 '12 at 09:39

themissionmars

107
9

3

Where? Please give an answer in the format of the question. So in this case valid php. – Luke Vincent Aug 25 '17 at 10:00
1

$im->setImageAlphaChannel(Imagick::ALPHACHANNEL_REMOVE ); – Chris Jun 03 '21 at 20:00

score 1 · Answer 4 · edited May 19 '15 at 05:45

1

change this code $im->setimageformat("jpg"); to this code $im->setimageformat("png"); if you face a background colour issue.

edited May 19 '15 at 05:45

aronadaal

9,083
1
19
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answered May 19 '15 at 05:24

Atif Khan

11
1

score 1 · Answer 5 · answered May 23 '11 at 16:23

1

If your version of Imagick is not up to date, the setImageBackgroundColor may be wrong.

Swap the following line

$im->setImageBackgroundColor("red");

to this (Imagick version >= 2.1.0)

$im->setBackgroundColor(new ImagickPixel("red"));

or (Imagick version < 2.1.0)

$im->setBackgroundColor("red");

answered May 23 '11 at 16:23

carlgarner

89
5

i made some changes in my question.. have a look.. and your suggestion is not working.. – Alfred May 23 '11 at 16:36
@blasteralfred Could you provide access to a copy of your PDF as I believe the issue may be related to that, rather than the code you've now provided above. The updated code works without issue with PDF that I have. – carlgarner May 26 '11 at 10:45

NIck · Answer 6 · 2021-12-10T07:24:37.653

1

Just use flattenImages() right after creating a new imagick():

$im = new Imagick('file.pdf[0]');
$im = $im->flattenImages();

Edit: The flattenImages method has been deprecated & removed. Use

$im = $im->mergeImageLayers( imagick::LAYERMETHOD_FLATTEN );

edited Dec 10 '21 at 07:24

answered Dec 02 '21 at 22:48

NIck

71
1
9

score 0 · Answer 7 · answered Nov 11 '21 at 22:18

After endless attempts to append a pdf file with a jpeg image without getting black areas, I found the solution: the function transformImageColorspace

Used in this order works perfectly:

$im = new Imagick();
$im->readImage("file.pdf");

$im->transformImageColorspace(Imagick::COLORSPACE_SRGB);

$im->setImageFormat('jpeg');
$im->writeImage('image.jpg');

score 0 · Answer 8 · answered Feb 24 '22 at 22:54

I would like to add to the excellent and helpful answers by saying that a slightly different approach is required if your PDF has multiple pages.

Something I was surprised to discover is that the Imagick class implements Iterable, which means you can run it through a foreach loop and operate on each page in turn (which it turns out is necessary because the layer, colour, and alpha channel changes appear to only take effect on the last page) which will be presented to you as a separate Imagick object:

$im = new Imagick('path/to/file.pdf');
foreach ($im as $c => $page)
{
    // do what you need to do with each page and then...
    $im->writeImage('path/to/image-'.$c.'.jpg');
}

php Imagemagick jpg black background

8 Answers8