[magick-users] Question regarding cropping image at center

[Jaikishan Jalan]

Hello,

I am using the following command to crop an area of 512x784 at the center of
the image. I want to output the file in tif format. Here is my command that
I am using
$ convert test.tif -gravity Center -crop 512x786+0+0 +profile \"*\" out.tif

However, it throws an error:

convert: incorrect count for field "MinSampleValue" (1, expecting 4); tag
ignored. `test.tif'.
convert: incorrect count for field "MaxSampleValue" (1, expecting 4); tag
ignored. `test.tif'.

and the out.tif fie is also empty. I was wondering if somebody can point me
my mistake.

-- 
Thanks,
Jaikishan