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Spreadpi issues on brower, cropping, manual trigger etc

Posted: 02 Feb 2016, 10:06
by saqib
Hello All,

i am new to bookscanner and having some issues which i want to discuss.

- i have canon powershot sx 170is *2
- installed chdk version: sx 170is- 101a-1.4.1-4381-full_alpha
- installed spreadpi on raspberrypi B. spreadpi version: nightly-spread 01 Nov 2015
- chdk and spreadpi are working fine, can access from browser and can take images.

- when i click on camera button using chrome browser it just hangs there saying "Please wait for the capture process to finish..." , i then have to refresh the page and then i can see the image in workflow. can not take more images in the same workflow, have to delete the old image to make it work again.
- is there any way i can set the crop area and that can be applied to all the images, so that i dont have to crop all images one by one.
- can i take images manually with the camera button without using spreadpi browser button or CLI.
- is it correct that maximum zoom value is 30?
- what exactly is post processing server?.

Thanks in advance.

Re: Spreadpi issues on brower, cropping, manual trigger etc

Posted: 02 Feb 2016, 11:36
by duerig
Hi. I'm not sure what state the nightly builds are in. The SpreadPi image that I have been using with some success is:

This is a custom build I made. It seems to work well with Chrome from what I remember. Perhaps the Chrome bug cropped up after I made that image.

When you set a crop area, it should be 'sticky' and will apply to new scans you take by default.

You can take images manually. In order to do this, make sure that the camera is disconnected from your Pi. When your camera is connected, all of the manual input buttons are disabled. Make sure that alt mode is disabled (no <ALT> text at bottom of camera screen). Then simply press the camera shutter button to go into rec mode and press it again to snap a photo. The photograph will show up on your camera's memory card just like normal. You can then plug the camera into your computer to copy off images or eject the memory card to do so.

The zoom values are an arbitrary sized step through the range of your camera. If your camera has 1x-8x zoom, then the maximum zoom number will be 8x and the minimum will be 1x. I presume that they are linearly distributed throughout the available range, but you'd have to check the CHDK documentation to be sure. Every camera has a potentially different maximum step value.

The post processing server was an interesting idea that Johannes had. A Pi is not powerful enough to do post-processing in a reasonable time. So he had the notion that you could run a server on a laptop or other more powerful computer and the Pi could automatically transfer images to it for post processing. I am not sure how far he got with this idea or whether it works. But if you look through the code and try it out, please report your experience.


Re: Spreadpi issues on brower, cropping, manual trigger etc

Posted: 03 Feb 2016, 02:12
by saqib
Hello duerig,

Thanks for the reply, i am downloading the image you send will try it out today.


Re: Spreadpi issues on brower, cropping, manual trigger etc

Posted: 03 Feb 2016, 09:55
by saqib

i downloaded and burned it on SD card, it worked fine i can now see the crop option but issue was when i click on the crop button the pop up is so over sized that i can not do cropping or cant even see the save button. i tried it on all browsers (firefox, chrome, IE) tried zoom in/out but result was same.

i had time so i started looking at the configuration files and by doing a little change in this file
i was able to do cropping and can now see save button after doing cropping.
it worked fine for like 4 hours or so i tested, i took some 10 - 20 images and then got busy with other stuff. now when i am trying to follow the same steps to scan a 100 page book i can not see the crop option, things are same as they were yesterday on the nightly build. this is so strange i dont understand whats happening.

one more thing, when i click on the camera button on the browser i dont see images in those boxes (grey boxes that appears after you create workflow) . i have to refresh the page to see the images taken.

any thoughts?