将tiff（带路径）转换为png并删除背景（透明） - 使用PHP中的Imagemagick

Question

So, i have a lot of tiff files and I want to generate thumbnails of them. This thumbnails must have a transparent background.

All tiffs have: a white background and a path along the object (e.g. a can of a coke) and are saved as CMYK.

So i tried a lot of convert commands (like these and also php Imagick::clipPath but nothing worked very well (background still there/corrupt image).

convert a.tif -clip -resize 800x600 a.png
convert a.tif -clip -alpha transparent +clip -channel A -resize 800x600 a.png

also this php code:

<?php
$image = new Imagick('a.tif');
$image->clipPath();    
$image->setImageFormat('png');    
$image->thumbnailImage(800, 600, true);
$image->writeImage('a.png');

here is an example tif file

Maybe somebody knows how to solve this.

EDIT:

The best result returns this: convert test.tif -clip -alpha transparent 1.png

But it saves the background and not the clipped object. (png)

Answer 1

Found it after trying it for hours.

convert can.tif -alpha transparent -clip -alpha opaque result.png

So it must be executed with e.g. shell_exec - I didn't found any possible solution to do it with the Imagick-PHP class.

The problem was an old imagemagick version and also the wrong order of command attributes.