Intervention/image · error · Intervention\Image\Exceptions\ModifierException

Failed to apply {class}, unable to set image resolution

Error message

Failed to apply {class}, unable to set image resolution

What it means

setResolution() forwards the DPI values to Imagick::setImageResolution($x, $y); a false return triggers this ModifierException. The generic ResolutionModifier constructor stores the floats without validating them, so zero or negative resolutions reach ImageMagick, which requires strictly positive values. This false-return branch is the rarer path; invalid resolutions more often throw ImagickException (sibling catch).

Source

Thrown at src/Drivers/Imagick/Modifiers/ResolutionModifier.php:25

use ImagickException;
use Intervention\Image\Exceptions\ModifierException;
use Intervention\Image\Interfaces\ImageInterface;
use Intervention\Image\Interfaces\SpecializedInterface;
use Intervention\Image\Modifiers\ResolutionModifier as GenericResolutionModifier;

class ResolutionModifier extends GenericResolutionModifier implements SpecializedInterface
{
    /**
     * @throws ModifierException
     */
    public function apply(ImageInterface $image): ImageInterface
    {
        $imagick = $image->core()->native();

        try {
            $result = $imagick->setImageResolution($this->x, $this->y);
            if ($result === false) {
                throw new ModifierException(
                    'Failed to apply ' . self::class . ', unable to set image resolution',
                );
            }
        } catch (ImagickException $e) {
            throw new ModifierException(
                'Failed to apply ' . self::class . ', unable to set image resolution',
                previous: $e,
            );
        }

        return $image;
    }
}

View on GitHub (pinned to 5598b9e397)

Solutions

1. Validate before calling: both x and y must be > 0
2. Default missing metadata to a sane DPI (72 for screen, 300 for print) instead of 0
3. Enforce numeric bounds (min:0.01 or min:1) on user-supplied DPI at the request boundary
4. If the call still fails, inspect the chained previous exception for the native wording

Example fix

// before
$image->setResolution($sourceDpi, $sourceDpi); // 0 when metadata absent

// after
$dpi = $sourceDpi > 0 ? $sourceDpi : 72.0;
$image->setResolution($dpi, $dpi);

if ($x <= 0 || $y <= 0) {
    throw new \InvalidArgumentException(sprintf('Resolution must be positive, got %F x %F', $x, $y));
}
$image->setResolution($x, $y);

function isValidResolution(float $x, float $y): bool
{
    return $x > 0 && $y > 0;
}

When it happens

Trigger: $image->setResolution(0, 72), setResolution(-1, -1), or DPI values computed from user input / EXIF / PDF metadata that can be 0.

Common situations: Export code copying resolution from a source whose metadata is missing (defaults to 0); PDF/EPS workflows where 0 DPI sneaks in; forms letting users type 0 into a DPI field.

Related errors

• Failed to apply {class}, unable to adjust image gamma
• Failed to read image resolution
• Failed to apply Intervention\Image\Drivers\Imagick\Modifiers
• Failed to apply Intervention\Image\Drivers\Imagick\Modifiers
• Failed to apply Intervention\Image\Drivers\Imagick\Modifiers

AI-assisted analysis of Intervention/image@5598b9e397 (2026-08-23). Data as JSON: /api/errors/11ca2d5463a1bbd0. Report an issue: GitHub.