NI MAX

[navystargazer]

I am not sure where to post this but I am using an NI 1426 Camera link board and NI MAX to acquire images.  My problem is that the pixel values change depending upon whether I save the image as a TIFF or PNG.  These are the only two options that are in MAX.

If I take a single image and then save it in each format and then compare, the values are different by up to +/- 20.

(The tif also seem to have the MSB set so I subtracted 32768 when I compared the values.)

Any ideas on which format is right ? 

[Kimberly_Wenger_Austin]

Hi navystargazer,

What types of images are you trying to save to file?  Images greater than 8 bits can only be stored in the PNG format. If you revert to 8 bits, you will be able to save your grayscale images as BMP and TIFF files along with PNG. Monochrome BMP and TIFF files only support 8 bit images.  Also how are you saving the images?  Are you going to File>>Save Image or right clicking on the image and selecting save?  Thanks!

Kim

[navystargazer]

I am using the Save Image button in the toolbar at the top of the MAX window.  It offers a choice of PNG or TIFF in the window that appears asking for a filename.  The camera is a 14 bit/pixel camera.  The tiff images appear to have 32768 added to the pixel value when I read the tiff e.g. 10000 becomes 42768.

I will stick to the PNG in the future......Thanks.

[navystargazer]

Followup questions:

If I am offered a choice of PNG or TIFF does that mean I have somehow gotten into an 8 bit mode ?

How would I be certain I am getting all my 14 bits ?

When I look at my PNG it certainly seems that I am getting all my bits but I thought that about my TIFFs also. 

[Kimberly_Wenger_Austin]

Hi,

The reason that it gives you multiple options for file formats is in case you need a specific type of file.  It doesn't switch to 8 bit mode and the best way to make sure that you are getting a 14 bit image is to specify this within LabVIEW.  Is there a specfic reason you need to have the images saved from MAX?

Kim