Octave Support for isetcam

[AyushJam]

While ISET is an amazing simulation tool, it depends on its user's having paid MATLAB licenses which might not be accessible to all individuals and organizations interested in using the toolbox.

GNU Octave is a free and open-source alternative for MATLAB. It imitates most MATLAB functionality with code and CLI but has different libraries, toolboxes, and datatypes. One third-party package of importance in isethdrsensor is openexr. With help from Brian and David, I was able to modify the current ISET codebase to work with Octave 6.4.0.

The changes are briefly described at the end of README.md and the necessary packages are listed in environment.yml and `octave-requirements.txt.

This PR goes along with the two others opened in iset3d-tiny and isethdrsensor repos. All these branches are named dev-octave. I have tested this code on Octave 6.4.0.

Hope this helps extend access to ISET!

[digital-pro]

Can we tell whether we're running under Octave and only hardcode the filter names if we are?

[wandell]

Maybe Ayush can insert an ‘isOctave’ test at the relevant locations? function retval = isOctave persistent cacheval; if isempty (cacheval) cacheval = (exist ("OCTAVE_VERSION", "builtin") > 0); end retval = cacheval; end Putting it in the relevant spots has some value because we then know which parts of the code are modified for Octave – which I think is a great thing. (Very glad that people could use Octave.) From: David Cardinal ***@***.***> Date: Friday, July 25, 2025 at 2:47 PM To: ISET/isetcam ***@***.***> Cc: Subscribed ***@***.***> Subject: Re: [ISET/isetcam] Octave Support for `isetcam` (PR #37) @digital-pro commented on this pull request.

________________________________ In sensor/sensorCreate.m<#37 (comment)>:

@@ -357,10 +357,14 @@

end qeFile = fullfile(isetRootPath,'data','sensor','colorfilters','OVT','ovt-large.mat'); - wave = sensorGet(sensor,'wave'); - [data,filterNames] = ieReadColorFilter(wave,qeFile); - sensor = sensorSet(sensor,'filter spectra',data); - sensor = sensorSet(sensor,'filter names',filterNames); + wave = sensorGet(sensor, 'wave'); + [data, ~] = ieReadColorFilter(wave, qeFile); + + % Hardcoded filter names (since Octave can't read the cell array from .mat) + filterNames = {'r', 'g', 'b'}; Can we tell whether we're running under Octave and only hardcode the filter names if we are? — Reply to this email directly, view it on GitHub<#37 (review)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AAOAQWLGPLQDSMRVVPO22JD3KKQVLAVCNFSM6AAAAACCKKV4NWVHI2DSMVQWIX3LMV43YUDVNRWFEZLROVSXG5CSMV3GSZLXHMZTANJWHA3DCMBSGQ>. You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[digital-pro]

Brian's function looks like a good way to address the issue. 

That way the changes will be isolated to Octave users. Otherwise I don't think we have enough test coverage in our validation suite to make sure something subtle isn't broken for Matlab users.

In any case, as Brian said, this is really cool!

[AyushJam]

Yes, I can indeed add an isOctave test. However, please note that apart from filterNames, there are a few other places like headers and datatypes where the flag will appear too. I'll push the update soon.

Glad you found this useful!