Was stimmt hier nicht!

#!/usr/bin/perl -w
# Script to compress Images in a Directory
# Some parts of this file are from http://pronix.linuxdelta.de
# last update: 10.04.2007

print "Programmname: $0\n\n";

opendir(DH, ".") or die "Fehler bei opendir : $!\n";
while(defined($name=readdir(DH))){
   print $name , "\n" if $name=~m/.*\.txt/;
   /usr/local/bin/convert -quality 70 $name;
   #print $name, "\n";  
}
closedir DH;

Administration 524 $ ./compress_image 
Use of /c modifier is meaningless without /g at ./compress_image line 12.
Bareword found where operator expected at ./compress_image line 12, near "/bin/convert"
        (Missing operator before nvert?)
Unquoted string "nvert" may clash with future reserved word at ./compress_image line 12.
Number found where operator expected at ./compress_image line 12, near "quality 70"
        (Do you need to predeclare quality?)
Scalar found where operator expected at ./compress_image line 12, near "70 $name"
        (Missing operator before  $name?)
syntax error at ./compress_image line 12, near "/usr/local"
Execution of ./compress_image aborted due to compilation errors.
Administration 525 $

system "ls -l /etc/hosts";

#!/usr/bin/perl -w
# Script to compress Images in a Directory
# Some parts of this file are from http://pronix.linuxdelta.de
# last update: 10.04.2007

print "Programmname: $0\n\n";

opendir(DH, ".") or die "Fehler bei opendir : $!\n";
while(defined($name=readdir(DH))){
   print $name , "\n" if $name=~m/.*\.txt/;
   system "/usr/local/bin/convert - quality 70 $name";
   #/usr/local/bin/convert -quality 70 $name;
   #print $name, "\n";  
}
closedir DH;

Programmname: ./compress_image

convert: missing an image filename `.'.
convert: missing an image filename `..'.
convert: missing an image filename `compress_image'.
convert: missing an image filename `IMG_4065.JPG'.

find . -name '*.jpg' -type f -exec /usr/local/bin/convert -quality 70 {} \;