Keep EXIF Data of Images and Compress Uploaded to Wordpress withour Plugins

[Navodit Kumar]

ImageMagick and the Imagick PHP extension is installed on my host now. Now all generated images keep EXIF/IPTC info (original, medium and thumbnail image, all of them are with EXIF/IPTC data).

I allow visitors to upload hi-res images on site, and in most cases visitors do not optimize/compress images before upload and sometimes image file size is quite big.

For example 12MP image can be 10 MB, but after 85% jpeg compression its file size can be 2-3 times smaller, almost without noticeable loss of quality.

I put this function to functions.php (my theme folder) to compress original image during upload, to save up disk space and speed up loading of hi-res image on page with it.

// Image compression on upload, compress original image
function wt_handle_upload_callback( $data ) {
$image_quality = 50; // 50% compression
$file_path = $data['file'];
$image = false;

switch ( $data['type'] ) {
case 'image/jpeg': {
$image = imagecreatefromjpeg( $file_path );
imagejpeg( $image, $file_path, $image_quality );
break;
}

case 'image/png': {
$image = imagecreatefrompng( $file_path );
imagepng( $image, $file_path, $image_quality );
break;
}

case 'image/gif': {
// Nothing to do
break;
}
}

return $data;
}
add_filter( 'wp_handle_upload', 'wt_handle_upload_callback' );
add_filter ('image_strip_meta', false);

[Wonder Woman]

You are using funcions from GD library to manipulate images, not functions from WordPress. In the links I shared you can see how to enable EXIF data for GD library and also for ImageMagick. Unless you use WordPress API, the filter image_strip_meta doesn't apply to your code. Also, the image_strip_meta is only available if ImageMagick is installed.