/**
* Go over all KalturaThumbAsset thumbnails and look for an exact match.
* If none is found, look for the one with the nearest aspect ratio (i.e. the one
* with the smallest distance from the original). If there are several with the
* same delta from original - the one with the largest dimensions will be picked.
*
* @param array $thumbAssets ThumbAsset objects array
* @param int $requiredWidth Thumbnail's requested width
* @param int $requiredHeight Thumbnail's requested height
* @return kThumbnailDescriptor|null The thumbnail asset with exact/closest
* aspect ratio to the required, or null
* if the entry doesn't contain thumbnails.
*/
public static function getNearestAspectRatioThumbnailDescriptorFromThumbAssets($thumbAssets, $requiredWidth, $requiredHeight, $fallbackThumbnailPath = null)
{
// Calc aspect ratio + distance from requiredAspectRatio
$chosenThumbnailDescriptor = null;
kThumbnailDescriptor::initDimensions($requiredWidth, $requiredHeight);
if ($fallbackThumbnailPath) {
$imageSizeArray = getimagesize($fallbackThumbnailPath);
$thumbWidth = $imageSizeArray[0];
$thumbHeight = $imageSizeArray[1];
$chosenThumbnailDescriptor = kThumbnailDescriptor::fromParams($thumbWidth, $thumbHeight, $fallbackThumbnailPath, true);
}
if (empty($thumbAssets)) {
return $chosenThumbnailDescriptor;
}
// Loop all available thumb assets and choose the best match
foreach ($thumbAssets as $thumbAsset) {
$descriptor = kThumbnailDescriptor::fromThumbAsset($thumbAsset);
if (!$chosenThumbnailDescriptor) {
$chosenThumbnailDescriptor = $descriptor;
} else {
// Compare the last best-match with the current descriptor
$res = self::compareThumbnailDescriptors($chosenThumbnailDescriptor, $descriptor);
// Keep the last best-match unless it needs to go down the ranks (in case $res > 0)
$chosenThumbnailDescriptor = $res <= 0 ? $chosenThumbnailDescriptor : $descriptor;
}
}
return $chosenThumbnailDescriptor;
}
