Gocr gives an error while it is trying to read a pic sometimes

[Halid Faith]

I use spamassassin3.1.7, fuzzyocr, gocr0.44 ( Before I used gocr 0.41 and
0.43 )

Gocr gives an error while it is trying to read a picture sometimes as below;

1 - gocr -l 180 -d 2 -i italic.gif
giftopnm: Reading Image Sequence 0
giftopnm: EOF or error reading data portion of 59 byte DataBlock from file
(null): Error reading magic number from Netpbm image stream.  Most often,
this means your input file is empty.


2 - On another picture,
giftopnm: Reading Image Sequence 0
# Warning: non-positive median line gap of 0


How can I fix above errors ?

Thanks