hight memory usage with images on dash

[Danfro]

If there are several images on the dash the app takes up quite some memory and does take a while to load.

Memory after reboot before start of app:

Memory after starting camera scanner with 5 images on dash:

Memory after deleting 4 images and restarting camera scanner:

[Danfro]

Maybe worth to mention. All images where taken from within the app (that is imported straight from camera).

[jonnius]

Thanks for your hint. I see two ways to reduce storage used by cache:

• Reduce image resolution on import (configurable)
• Do not cache result images with documents and rerun image processing on app start (configurable)
• Do not cache the session at all (configurable)

To reduce RAM usage:

• Do not hold images in backend, but read files from cache each time an image is requested (only possible if images are cached)
• Reduce image resolution for displaying (configurable, only helpful if images have not already been reduced on import)

[Danfro]

Can maybe thumbnails be loaded/shown on the dash?
Gallery app must be doing something in the line.

Then load the full image only for processing/editing.
That should at least sort startup time.

[jonnius]

I think loading the images into RAM is what takes most of the time. So the only way to speed that up would be to save a thumbnail along with each image for displaying purpose.

But I don't think the camera scanner should scale up that much. It is not meant as a gallery, just as a session of scans to be exported as a PDF together. Maybe we should ask the user on startup whether he wants to restore the previous sessions and delete it otherwise. Also we are planning to have a "new session" button that clears the session.