public static function process_pdf_page($post_id, $current_page, $page_number, $pdf_pages_number, $pdf_file_path, $pdf_upload_dir, $jpeg_resolution, $jpeg_compression_quality, $ratio)
{
$_img = new Imagick();
$_img->setResolution($jpeg_resolution, $jpeg_resolution);
$_img->readImage($pdf_file_path . '[' . ($current_page - 1) . ']');
$_img->setImageCompression(Imagick::COMPRESSION_JPEG);
$_img->resizeImage(1024, round(1024 / $ratio), Imagick::FILTER_BESSEL, 1, false);
$_img->setImageCompressionQuality($jpeg_compression_quality);
$_img->setImageFormat('jpg');
//$_img->setImageInterlaceScheme(Imagick::INTERLACE_JPEG);
$_img->transformImageColorspace(Imagick::COLORSPACE_SRGB);
//$_img->setBackgroundColor(new ImagickPixel('#FFFFFF'));
// Remove transparency, fill transparent areas with white rather than black.
//$_img->mergeImageLayers(Imagick::LAYERMETHOD_FLATTEN);
// Convert to RGB to prevent creating a jpg with CMYK colors.
$white = new Imagick();
$white->newImage(1024, round(1024 / $ratio), "white");
$white->compositeimage($_img, Imagick::COMPOSITE_OVER, 0, 0);
$white->setImageFormat('jpg');
$white->setImageColorspace($_img->getImageColorspace());
$white->writeImage($pdf_upload_dir . '/page-' . $page_number . '.jpg');
$_img->resizeImage(76, round(76 / $ratio), Imagick::FILTER_BESSEL, 1, false);
$white = new Imagick();
$white->newImage(76, round(76 / $ratio), "white");
$white->compositeimage($_img, Imagick::COMPOSITE_OVER, 0, 0);
$white->setImageFormat('jpg');
$white->setImageColorspace($_img->getImageColorspace());
$white->writeImage($pdf_upload_dir . '-thumbs/page-' . $page_number . '-100x76.jpg');
if ($current_page == 1) {
$file = $pdf_upload_dir . '/page-' . $page_number . '.jpg';
PdfLightViewer_Plugin::set_featured_image($post_id, $file, 'pdf-' . $post_id . '-page-' . $page_number . '.jpg');
}
$percent = $current_page / $pdf_pages_number * 100;
update_post_meta($post_id, '_pdf-light-viewer-import-progress', $percent);
update_post_meta($post_id, '_pdf-light-viewer-import-current-page', $current_page);
$_img->destroy();
unset($_img);
return $percent;
}
