Here\'s a question-based title that captures the essence of the article: How to Correctly Handle Image Orientation Issues with EXIF Data in PHP?

Handling Image Orientation with PHP's read_exif_data and Image Adjustments

PHP provides a convenient way to read and manipulate image EXIF data using the read_exif_data function. This function allows you to extract metadata like orientation, resolution, and camera settings from JPEG images.

When dealing with images uploaded from mobile devices (specifically iPhones and Android), you may encounter issues with incorrect image orientation due to the way these devices handle EXIF data. To address this, you can adjust the orientation of uploaded images before saving them.

The problem arises from comparing the original code with a more reliable solution that correctly rotates images based on the EXIF data. The original code had issues with orientation adjustment, while the second solution implements a more comprehensive approach, including both GD and ImageMagick libraries.

The Solution: Using GD or ImageMagick to Rotate Images

To fix the orientation issue, you can utilize either the GD or ImageMagick libraries to rotate the images accordingly. The below code snippets demonstrate how to implement this functionality:

GD Library:

<code class="php">function image_fix_orientation(&$image, $filename) {
    $exif = exif_read_data($filename);
    
    if (!empty($exif['Orientation'])) {
        switch ($exif['Orientation']) {
            case 3:
                $image = imagerotate($image, 180, 0);
                break;
            
            case 6:
                $image = imagerotate($image, 90, 0);
                break;
            
            case 8:
                $image = imagerotate($image, -90, 0);
                break;
        }
    }
}</code>

ImageMagick Library:

<code class="php">function image_fix_orientation($image) {
    if (method_exists($image, 'getImageProperty')) {
        $orientation = $image->getImageProperty('exif:Orientation');
    } else {
        $filename = $image->getImageFilename();
        
        if (empty($filename)) {
            $filename = 'data://image/jpeg;base64,' . base64_encode($image->getImageBlob());
        }
        
        $exif = exif_read_data($filename);
        $orientation = isset($exif['Orientation']) ? $exif['Orientation'] : null;
    }
    
    if (!empty($orientation)) {
        switch ($orientation) {
            case 3:
                $image->rotateImage('#000000', 180);
                break;
            
            case 6:
                $image->rotateImage('#000000', 90);
                break;
            
            case 8:
                $image->rotateImage('#000000', -90);
                break;
        }
    }
}</code>

In conclusion, using either the GD or ImageMagick libraries as demonstrated in the code snippets will allow you to accurately rotate images based on their EXIF data, ensuring proper orientation when uploading images from mobile devices to your PHP application.

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