OK!!!! It works! The option --custom-gamma=no solves the problem. Thank you very much for your help. Bye Piernicola
On Tuesday 19 November 2002 22:57, Oliver Rauch wrote: > Hello. > > You walked into a little trap with the default options of the > sane-umax backend. By default the option "custom-gamma" is > enabled what means that you have to send a gamma table > or you have to disable the option "custom-gamma". > > When you do > scanimage -d umax:/dev/sgb --source "Transparency Adapter" --resolution 300 > -l 30 -t 10 -x 175 -y 225 --depth 12 --custom-gamma=no > then you should get good results. > > I will think about it if there is a chance to get rid of this trap. > > Bye > Oliver > > Piernicola Oliva schrieb: > > Hi, > > I'm sorry for annoying you again, but I can't solve the problem. > > I am using the command > > > > scanimage -d umax:/dev/sgb --source Transparency Adapter --resolution > > 300dpi -l 30 -t 10 -x 175 -y 225 --depth 12 > > > > so I should obtain 12bit (in two byte) per channel per pixel. > > But this is a picture of bytes (two for one channel) that I obtain: > > > > 00001001 - 10100000 > > 00001010 - 11110000 > > 00001000 - 00100000 > > 00001001 - 01100000 > > 00001010 - 10010000 > > 00001000 - 01100000 > > 00001001 - 10000000 > > 00001010 - 10110000 > > 00001000 - 10000000 > > 00001001 - 11100000 > > 00001010 - 11010000 > > 00001000 - 11000000 > > 00001001 - 11100000 > > 00001010 - 11110000 > > 00001000 - 10010000 > > 00001001 - 10100000 > > 00001010 - 11010000 > > 00001000 - 01100000 > > 00001001 - 10100000 > > 00001010 - 11000000 > > 00001000 - 00110000 > > 00001001 - 10000000 > > 00001010 - 10000000 > > > > as you can see, they 8 bits values shifted of 4 bits. > > what happens? > > Am I doing something wrong? > > Thank you > > Pier > > > > On Saturday 16 November 2002 00:16, Oliver Rauch wrote: > > > When you do not use any gamma table options it is ok. > > > > > > SANE supports images with a color depth of 8 or 16 bits/sample. > > > A 12 bit sample does use 16 bits (2 bytes). The raw data of UMAX > > > or Linotype scanners already is transfered from the scanner to the > > > backend in this format. It is the raw format of the scanner. > > > > > > Best regards > > > Oliver > > > > -- > > \ name: Piernicola OLIVA > > o/\_ address: Universita' degli Studi di Sassari > > <\__,\ Struttura Dipartimentale di Matematica e Fisica > > "> | via Vienna 2, 07100, Sassari, Italia > > ` | tel: +39/079229486 (office) > > \ +39/3401450473 (mobile) > > \ fax: +39/079229482 > > \ e-mail: [email protected]
