image - montage command of ImageMagick does not read from file -

i use ubuntu 14.0.4. can use command label each image it's name:

montage -label '%t' -size 512x512 "./img/*.*[120x90]" -geometry +5+5 photo.png 

i want label images list of strings, written in text file. docs say:

-label name

use option assign specific label image ... if first character of string @, image label read file titled remaining characters in string. labels in file literal, no embedded formatting characters recognized.

but not use file provide label. use command this:

montage -label @un.txt -size 512x512 "./img/*.*[120x90]" -geometry +5+5 photo.png  

above, un.txt name of text file in ./img/ path. sample result:

in result, images labeled string @un.txt instead of content of un.txt. error in terminal:

montage.im6: improper image header `./img/un.txt' @ error/txt.c/readtxtimage/429

if move un.txt current (.) directory , run above command again, image (there no label) , below error:

montage.im6: not authorized `@un.txt' @ error/property.c/interpretimageproperties/2959.

note:

1. all images jpg
2. the version of imagemagick imagemagick 6.7.7-10

updated answer

maybe have wrong syntax label:

convert -size 100x100 xc:red label:@label.txt -append result.png 

where label.txt contains fred.

original answer

it related vulnerability discovered in imagemagick, see here.

you need update site policy file. can discover location running this:

convert -debug configure logo: null: 2>&1 | grep -ei "searching|loading" 

and in same directory/folder other xml config files.