Daniel Reetz, the founder of the DIY Book Scanner community, has recently started making videos of prototyping and shop tips. If you are tinkering with a book scanner (or any other project) in your home shop, these tips will come in handy. https://www.youtube.com/channel/UCn0gq8 ... g_8K1nfInQ

Camera video output as picture-in-picture

Everything camera related. Includes triggers, batteries, power supplies, flatbeds and sheet-feeding scanners, too.
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Camera video output as picture-in-picture

Post by vitorio » 09 Nov 2014, 17:56

How do you know what your cameras are doing, when they're on the sides of the machine and you're in front of it? How do you know when CHDK messes up and gets your camera stuck in the menus?

Haven't seen anyone do this, so while I was swapping out the Raspberry Pi model B for a model B+ (getting rid of the USB hub and maybe fixing some intermittent camera connection issues in the process), I thought I'd make this upgrade as well.
pip01.jpg (128.16 KiB) Viewed 3973 times
The LCD I was using with the Raspberry Pi controlling computer (using DVI) supports picture-in-picture for its composite (single yellow cable) and S-Video inputs. The Canon A2200s support composite video output, which replaces the built-in LCD output. The scanner is draped in blackout cloth, which you have to move to get to the cameras. So: a composite video switcher with both camera's AV outputs, on the LCD's PIP.

Now, you can see the software setting up the camera, and can switch between them with a button to make sure they're both working alright, which is helpful to make sure CHDK didn't get stuck:
pip02.jpg (127.38 KiB) Viewed 3973 times
Here's a video of what you can see while the Pi is initializing the cameras:

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Re: Camera video output as picture-in-picture

Post by duerig » 09 Nov 2014, 20:49

That is the best use of picture-in-picture that I've ever seen. My monitor didn't have composite-in, so I ended up buying a couple of mini 4" backup-camera display TVs to do the same thing.

One of the things I love about people in the forums here is the innovative uses they find for the boring and pedestrian things in our lives. This is a great example of that.

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Re: Camera video output as picture-in-picture

Post by daniel_reetz » 11 Nov 2014, 10:24

More Vitorio excellence. :) Thanks man.

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