Hi,

[wahbi]

Is anyone has an idea how to read a 16 bits signed tif file with IMAQ Vision (with my tests, file is read but the image is not correct. it seems that IMAQ translates negative values to positive ones)
Thanks in advance

Wahbi

[Jiri_2]

I remember that once I had to export this kind of files. You can convert it using arithmetic operator - multiplying all the image by two, substracking or adding 32768 etc. I do not remember exactly the procedure, but with the method trial and errors it is possible to find it.

Other way is the use of a look-up table which will convert the positive values higher than 32768 to the "negative" ones (btw. 0 and 32768).

If you send me a 16-bit tif file you need to convert, I can try it and describe the procedure more precisely.

Regards

Ferda, Ferda_Mr@seznam.cz

[hsch]

Hello Wahbi,

have you solved this problem ?

I´ve also have to read such TIF - files.
But i don´t now how.

Hsch

[Deanna Zhang]

I had to do this also...I had a ccd camera that was giving me 10 bit depth per pixel and I needed to output a 16 bit tif. What I did was convert image to array; subtract 512 from each pixel; multipy by 64 (that will put your range from -32768 to 32767, which is the range of a 16 bit image). Then I converted the array back to an image. If you are making your 16 bit image from 8 bits then you would substract 128 and multiply by 256. I hope this helps.
Deanna

[Charles Haworth]

I am trying to open an unusual 12 bit tiff file into imaq and the IMAQ read image vi keeps crashing at the call funtion dll. How can i open this file in labview?? can i somehow open as an array without using this call function and convert to 16bits?