强制下载图片

I want to force the download of an image. I have found this code:

<FilesMatch "\.(?i:jpg|gif|png)$">
    Header set Content-Disposition attachment
</FilesMatch>

but I have a special requirement. My images have an extension like .png

<a target="_blank" id="save_to_pc" href="/image.php?width=720&amp;height=480&amp;file=files/galleries/1549/01a750273f66cd8637bcd2811a34a3e5.jpg&amp;nocrop=1"></a>

can someone help me to filter this image and let the user download it?

You can do this by providing Content-Disposition in the header information of your image.php.

header('Content-Disposition: attachment; filename="<your image filename>"');