Leapster explorer webcam info

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Leapster Explorer Webcam info

All information on this page at the time of writing is pure conjecture, if you decide to experiment and buy any webcams that you see here and they don't work, don't blame me, just start thinking about who you know that would appreciate a webcam for christmas. Many thanks to Phillkll and claude for their help.


Overview

As we know, the leapster explorer is slated to have a Webcam addon released sometime in the Autumn. this is a short page detailing what we have discovered so far, including possible candidates for alternative cameras, driver compatibility and available software. Currently the only way to connect any usb peripherals to the explorer is via the proprietary camera connection, seen here: http://wtfmoogle.com/?p=1190 messing with this port can (and has) caused serious damage to your explorer including blown Regulators and/or blown/corrupted Nand chips. If you are unsure of what you are doing, come and ask on the #didj IRC channel on freenode

Cameras and Driver compatibility

Looking through the rootfs on the Leapster explorer we found that it uses the GSPCA_ZC3XX linux drivers: http://cateee.net/lkddb/web-lkddb/USB_GSPCA_ZC3XX.html (see modprobe.sh for more details), as you can see from the list this should provide us with many popular target devices to test for compatibility to the explorer without the need for compiling any drivers.

Here is another list of webcams with VID/PID information to aid in your search for compatible webcams http://mxhaard.free.fr/spca5xx.html Please refer back to vid/pid information from the 1st list to confirm that the VID/PID matches one from that driver list.

Whilst these webcams aren't the latest and greatest, they should be relatively easy to find 2nd hand or cheap, as a lot of those listed for PC were very popular and reasonable quality a few years ago, Philips, creative, logitech, with the Z-star models being vimicro chipset based and behind many a generic usb1.1 camera.


The explorer also modprobes uvcvideo, this is significant because that is for 'driverless' camera devices.

Here is a list of uvc cameras: http://www.ideasonboard.org/uvc/ (thanks Claude, who also noted that some uvc cameras do not like usb1.1 )

These also turn up cheap on dealextreme, I have no experience with these cameras at all so YMMV a lot with these types of cameras.

It should also be noted that whilst there may be some devices on both of the lists that may state they are USB2.0, its highly unlikely that they will surpass USB1.1 datarates (bear in mind some uvc cameras only like usb2), they are most likely usb2 compliant in spirit only :) These cameras are all low res (640x480) and likely drop the framerate to 15fps or less on their highest resolutions. If its a higher Res/Framerate camera then it may either not work at all (usb host incompatibility) or not work at higher framerates(usb datarate restrictions).


Which cameras to look at?

The philips webcams were very popular, they still have documentation for them on the philips webpage and they come with reasonable PC based software, these days they've been surpassed by much better cameras but for a small screen based camera they will be fine for the job.

the spc200nc, spc210nc, spc300nc, spc315nc are all from the philips toUcam range, google images should give you an idea of what to look out for at 2nd hand stores.

a quick look on ebay with specific model names (SPC210NC etc.) will turn you up a webcam from the list for under £8 inc shipping. Dealextreme should also be a good source for cameras but TRIPLE-DOUBLE CHECK the firmware VID/PID is in either of the lists lists before committing to buy. also 2nd hand computer stores should have many models, if in doubt see if they will plug it in so you can check the VID/PID :) and remember there is always the chance that even if it is in the list of VID/PIDs it still might not work. Don't forget to ask friends and family if they have old webcams too!!


This Section will be updated as and when new information about other webcams is obtained.


Software

Ok, so, you got lucky, got yourself a cheap webcam on the list, the explorer enumerates it and it or you load an appropriate driver, so what next? You'll need some software, again, these are untested with a webcam, your mileage may very and of course any damage to your kit is your own fault, I won't be held responsible.

Looking in /usr/bin you will find a number of potentially camera related apps.

Cameo, Camera, flipbook, slideshow, snapshot, viewfinder, and viewshot.

You can run these apps directly on the explorer, if you find anything by running these apps. on the explorer, please come back and add your findings to the wiki. Whilst none of these apps will not be of any use to Didj owners, you can use your didj to gain more information about what these files do if you don't have an explorer. these apps are found in /usr/bin on the explorer, place them in your Didj/Base/bin folder, if you run an app. use the --help switch, this should give you usage instructions.

both cameo and camera seem to be the same app, to display a live video stream at the very least, if you look at their usage information you will find they're both called 'periodicsnap', and some of the switches aren't actually listed, so these appear to be test apps or WIP. Also of note is the fact that one of the switches -w 'disable SDL hardware accel.' directly references SDL, this might be a hint that the explorer has or will have sdl support somewhere along the line which will be handy for any emulator programmers.

Both apps open layer2 (video layer) and display garbage (on a didj at least), both fail on opening /dev/video0 (camera).

flipbook is a bit of a mystery, Not entirely sure whether it is related to the camera, it tries to read a directory for files named Particle_xxxx.png, not sure what it tries to do after that.


Slideshow reads a directory for jpg images, I'm guessing displaying them at a given speed (although there doesn't appear to be a switch to specify the time between images).

Snapshot tries to open /dev/video0 (which I believe is the camera device) after that I'm guessing it does a frame grab from the camera and dumps it as a jpg file.

Viewfinder has much the same options as cameo/camera, although it doesn't manage to open the video layer, so no garbage on screen.

Viewshot is for viewing snaps that you've taken by the looks of things, it wants a jpg filename for input, you can run it on the didj if you like but it will most likely segfault on you :D




Hopefully someone with an explorer will confirm what I've found so far, and add their findings here.