Experimental Physics and
Industrial Control System

Hi John,

 I can verify that NDFileTIFF works and the NDPluginProcess will read an existing TIFF file successfully so it seems
 the sequencer automation to save the file is broken in some way.

I think maybe you are misunderstanding what the Save button does.  It does not save to a TIFF file.  It saves the current NDArray to a memory buffer in the plugin to be used for subsequent background subtraction.  The TIFF functionality in NDPluginProcess only reads an existing TIFF file, it does not save to a TIFF file.

To load that background buffer you should either use the Save button (to use the current NDArray as the background) or use the Read button to read a pre-existing TIFF file and use that as the background.

If you want to save an NDArray to a TIFF file for subsequent use in the NDProcess plugin (either as background or flat field) you can just use the normal NDFileTIFF plugin.

Mark





From: Tech-talk <tech-talk-bounces at aps.anl.gov> on behalf of John Dobbins via Tech-talk <tech-talk at aps.anl.gov>
Sent: Wednesday, September 2, 2020 1:50 PM
To: EPICS Tech Talk
Cc: Keara Louise Soloway
Subject: areaDetctor NDPluginProcess Background Saving

areaDetector fans,

I have an IOC  based on

base-7.0.2
alive-R1-1-1
asyn-R4-40
autosave-R5-10
busy-R1-7-2
calc-R3-7-3
iocStats-3-1-16
sscan-R2-11-3
seq-2-2-6

it happens to be for a ADVimba camera but I don't think my issue is related to this.

When I try to use "Save Background" in NDPluginProcess nothing happens  ( well I can easily verify step 2-6  below don't happen).

 [from areaDetector R3-3 release notes]

Add an sseq record to load the background image from a TIFF file. This executes all the following steps:

     *   Saves the current NDArrayPort for the Process plugin to a temporary location
     *   Sets the NDArrayPort to the TIFF plugin.
     *   Enables ArrayCallbacks for the TIFF plugin in case they were disabled.
     *   Process the ReadFile record in the TIFF plugin. This reads the TIFF file and does callback to the Process plugin.
     *   Loads the NDArray from the callback into the background image.
     *   Restores the previous NDArrayPort from the temporary location.

I can verify that NDFileTIFF works and the NDPluginProcess will read an existing TIFF file successfully so it seems the sequencer automation to save the file is broken in some way.


When I press my  S7F:Proc1:SaveBackground button on the MEMD screen I see that both records

S7F:Proc1:SaveBackground

and

S7F:Proc1:SaveBackground_RBV

process,

S7F:Proc1:SaveBackground transitions to Yes and stays there.
S7F:Proc1:SaveBackground_RBV starts and stays at No.

I am hoping for a suggestion regarding what to check next.

Thanks,

John Dobbins

Research Support Specialist
Cornell High Energy Synchrotron Source
Cornell University

www.chess.cornell.edu<http://www.chess.cornell.edu>

Maybe it's all part of a great big ineffable plan. - Neil Gaiman, _Good Omens_