Imagick driver writes white image after resize

[storeman]

Describe the bug
I have a large JPEG file which results in a white output file (with correct dimensions) after resizing. If I use Imagick directly from within PHP it works correctly (at least with the thumbnailImage method). Also when using the GD-driver, the results are as expected.

After more fiddling, even leaving the resize call out of it, results in a white image, see code sample below.

Code Example

Expected behavior
I expect the st-john2.jpg to have the same file size and content. Instead the original is ~25MB and the new version ~180kB

Images
I can provide the image using PB, due to copyright.

EDIT
This image has the same behaviour: http://pictures.4ever.eu/data/download/buildings/bridges/st-johns-bridge,-forest,-hill-245439.jpg?no-logo

\Intervention\Image\ImageManager::imagick()->read('st-john-xl.jpg')->save('st-john2.jpg');

Environment (please complete the following information):

• PHP Version: 8.2.13
• OS: Docker (PHP-FPM)
• Intervention Image Version: 3.2.3
• Imagick 3.7.0 / ImageMagick 6.9.11-60 Q16 x86_64 2021-01-25

[storeman]

After some more digging, this problem doesn't occur when removing line Intervention\Image\Drivers\Imagick\Decoders\BinaryImageDecoder::32

The coalesceImages() call causes the image to become empty/white.

The question now is, is this a InterventionImage bug, or an Imagick bug. Or is the image corrupt...

A possible fix could be to replace line 32, but I cannot oversee if this would break stuff. I did a quick test resizing an animated GIF and the image mentioned in the start post.

        $imagickCoalesced = $imagick->coalesceImages();
        if ($imagickCoalesced->count() !== $imagick->count()) {
            $imagick = $imagickCoalesced;
        }

[olivervogel]

That's strange. I just checked it with the image from the URL in my environment and could not reproduce the problem described.

Everything ok

ImageManager::imagick()
    ->read('images/st-john-xl.jpg')
    ->resize(300, 200)
    ->save('images/st-john-xl-2.jpg');

PHP: 8.2.14
Host OS: Mac OS 13
Intervention Image Version: 3.2.3
Imagick 3.7.0 / ImageMagick 7.1.1-24 Q16-HDRI aarch64 21856

[olivervogel]

I checked it again on Debian. Here I can see the effect with the white background. Unfortunately, that doesn't get me any further at the moment.

Bug reproducable

PHP: 8.1.26
Host OS: Debian
Intervention Image Version: 3.2.3
Imagick 3.7.0 / ImageMagick 6.9.11-60 Q16 x86_64 2021-01-25

Bug reproducable

PHP: 8.2.14
Host OS: Debian
Intervention Image Version: 3.2.3
Imagick 3.7.0 / ImageMagick 6.9.11-60 Q16 x86_64 2021-01-25

[storeman]

Thanks Oliver for checking.

I updated my previous message, because I missed your reply:

The coalesceImages() call causes the image to become empty/white.

The question now is, is this a InterventionImage bug, or an Imagick bug. Or is the image corrupt...

A possible fix could be to replace line 32, but I cannot oversee if this would break stuff. I did a quick test resizing an animated GIF and the image mentioned in the start post.

    $imagickCoalesced = $imagick->coalesceImages();
    if ($imagickCoalesced->count() !== $imagick->count()) {
        $imagick = $imagickCoalesced;
    }

Basically this checks if coalesceImages() does anything. If not, continue working with the original.

[olivervogel]

After further tests, I currently see no other possibility than to call coalesceImages() only for animated images all image formats except Jpeg. Because Jpeg has no transparency and can not be animated.

Although I cannot understand the logic of this error at all.

It could very well be a bug in ImageMagick. This could even be fixed with ImageMagick >= 7.1.1-24, as no error occurred with this version in my tests. However, this is just speculation and would have to be checked.

[olivervogel]

This issue should be kept in mind. The described bug was only fixed with a workaround and a more permanent solution should be sought.