scanimage returns a broken image

[domidodo]

Hi,
i want to use a raspberry pi (Debian) as scan-Server.
For this job I installed SANE and ImageMagick.

If I scan with ...

scanimage -p --resolution=25 --mode=Color -l 0 -t 0 -x 210mm -y 297mm >test.pnm

... I will get an unreadable pnm-file. (In the attachments)

Based on the header, I found out that the file is smaller than it should be and I tried to fix this with ...

dd if=/dev/zero bs=40000 count=1 >> test.pnm

now I have a pnm-file which I can convert to an image with ...

convert test.pnm test.jpg

The problem is that the result does not match the scanned document.
Here is the difference between is and should:

Does someone have any idea how to fix this?


---------------------
Possibly the the result of "scanimage -T" is interesting too:

scanimage: scanning image of size 637x877 pixels at 24 bits/pixel
scanimage: acquiring RGB frame, 8 bits/sample
scanimage: reading one scanline, 1911 bytes...  PASS
scanimage: reading one byte...          FAIL No data
scanimage: stepped read, 2 bytes...     FAIL No data
scanimage: stepped read, 4 bytes...     FAIL No data
scanimage: stepped read, 8 bytes...     FAIL No data
scanimage: stepped read, 16 bytes...    FAIL No data
scanimage: stepped read, 32 bytes...    FAIL No data
scanimage: stepped read, 64 bytes...    FAIL No data
scanimage: stepped read, 128 bytes...   FAIL No data
scanimage: stepped read, 256 bytes...   FAIL No data
scanimage: stepped read, 512 bytes...   FAIL No data
scanimage: stepped read, 1024 bytes...  FAIL No data
scanimage: stepped read, 2048 bytes...  PASS
scanimage: stepped read, 2047 bytes...  PASS
scanimage: stepped read, 1023 bytes...  FAIL No data
scanimage: stepped read, 511 bytes...   FAIL No data
scanimage: stepped read, 255 bytes...   FAIL No data
scanimage: stepped read, 127 bytes...   FAIL No data
scanimage: stepped read, 63 bytes...    FAIL No data
scanimage: stepped read, 31 bytes...    FAIL No data
scanimage: stepped read, 15 bytes...    FAIL No data
scanimage: stepped read, 7 bytes...     FAIL No data
scanimage: stepped read, 3 bytes...     FAIL No data

 

[wizardfromoz]

G'day @domidodo and welcome

I am moving this Thread to Single Board Computers where it may gain better viewing and help.

Good luck

Chris Turner
wizardfromoz