nextcloud/lib/private/Preview/HEIC.php

145 lines
4.2 KiB
PHP

<?php
declare(strict_types=1);
/**
* @copyright Copyright (c) 2018, ownCloud GmbH
* @copyright Copyright (c) 2018, Sebastian Steinmetz (me@sebastiansteinmetz.ch)
*
* @author Robin Appelman <robin@icewind.nl>
* @author Roeland Jago Douma <roeland@famdouma.nl>
* @author Sebastian Steinmetz <462714+steiny2k@users.noreply.github.com>
* @author Sebastian Steinmetz <me@sebastiansteinmetz.ch>
*
* @license AGPL-3.0
*
* This code is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License, version 3,
* along with this program. If not, see <http://www.gnu.org/licenses/>
*
*/
namespace OC\Preview;
use OCP\Files\File;
use OCP\IImage;
use OCP\ILogger;
/**
* Creates a JPG preview using ImageMagick via the PECL extension
*
* @package OC\Preview
*/
class HEIC extends ProviderV2 {
/**
* {@inheritDoc}
*/
public function getMimeType(): string {
return '/image\/hei(f|c)/';
}
/**
* {@inheritDoc}
*/
public function isAvailable(\OCP\Files\FileInfo $file): bool {
return in_array('HEIC', \Imagick::queryFormats("HEI*"));
}
/**
* {@inheritDoc}
*/
public function getThumbnail(File $file, int $maxX, int $maxY): ?IImage {
$tmpPath = $this->getLocalFile($file);
// Creates \Imagick object from the heic file
try {
$bp = $this->getResizedPreview($tmpPath, $maxX, $maxY);
$bp->setFormat('jpg');
} catch (\Exception $e) {
\OC::$server->getLogger()->logException($e, [
'message' => 'File: ' . $file->getPath() . ' Imagick says:',
'level' => ILogger::ERROR,
'app' => 'core',
]);
return null;
}
$this->cleanTmpFiles();
//new bitmap image object
$image = new \OC_Image();
$image->loadFromData($bp);
//check if image object is valid
return $image->valid() ? $image : null;
}
/**
* Returns a preview of maxX times maxY dimensions in JPG format
*
* * The default resolution is already 72dpi, no need to change it for a bitmap output
* * It's possible to have proper colour conversion using profileimage().
* ICC profiles are here: http://www.color.org/srgbprofiles.xalter
* * It's possible to Gamma-correct an image via gammaImage()
*
* @param string $tmpPath the location of the file to convert
* @param int $maxX
* @param int $maxY
*
* @return \Imagick
*/
private function getResizedPreview($tmpPath, $maxX, $maxY) {
$bp = new \Imagick();
// Layer 0 contains either the bitmap or a flat representation of all vector layers
$bp->readImage($tmpPath . '[0]');
$bp->setImageFormat('jpg');
$bp = $this->resize($bp, $maxX, $maxY);
return $bp;
}
/**
* Returns a resized \Imagick object
*
* If you want to know more on the various methods available to resize an
* image, check out this link : @link https://stackoverflow.com/questions/8517304/what-the-difference-of-sample-resample-scale-resize-adaptive-resize-thumbnail-im
*
* @param \Imagick $bp
* @param int $maxX
* @param int $maxY
*
* @return \Imagick
*/
private function resize($bp, $maxX, $maxY) {
list($previewWidth, $previewHeight) = array_values($bp->getImageGeometry());
// We only need to resize a preview which doesn't fit in the maximum dimensions
if ($previewWidth > $maxX || $previewHeight > $maxY) {
// If we want a small image (thumbnail) let's be most space- and time-efficient
if ($maxX <= 500 && $maxY <= 500) {
$bp->thumbnailImage($maxY, $maxX, true);
$bp->stripImage();
} else {
// A bigger image calls for some better resizing algorithm
// According to http://www.imagemagick.org/Usage/filter/#lanczos
// the catrom filter is almost identical to Lanczos2, but according
// to http://php.net/manual/en/imagick.resizeimage.php it is
// significantly faster
$bp->resizeImage($maxX, $maxY, \Imagick::FILTER_CATROM, 1, true);
}
}
return $bp;
}
}