Tenrec-Builders / pi-scan

Pi Scan is a simple, robust capture appliance for book scanners. It runs on a Raspberry Pi 2.
BSD 2-Clause "Simplified" License
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Enable LiveView #6

Open lazzarello opened 7 years ago

lazzarello commented 7 years ago

CHDK for many powershot cameras, including the A2500 has a live viewfinder feature. This would make camera calibration much simpler since it the zoom settings could be done in realtime via touchscreen.

the upstream chdkptpgui project supports this with an example GUI written with two Lua frameworks.

The challenge would be to port that code to Python/Kiva

duerig commented 7 years ago

A couple of notes on this:

(1) Live View is the least stable part of chdkptp. When I've used it in the past, it has been the most likely to crash the program or the camera.

(2) I'm not sure whether the Pi is up to a fast live view. But maybe that wouldn't matter. Maybe an update every 5 seconds or somesuch would be fine.

(3) The ideal case would be if we manage to cleanly grab a frame as JPEG once every so often. Then it would be easy to add that into the existing Kivy interface.

This isn't a high priority for me right now. Currently, I've been looking at doing fiducial markers for cropping which somewhat reduces the need for live view (camera isn't zoomed in as much, it is easy to see where the book is supposed to sit). But if you submit a pull request, I'll accept it.