Active Topics

 



Notices


Reply
Thread Tools
jkq's Avatar
Posts: 251 | Thanked: 131 times | Joined on Oct 2009 @ USA
#41
Darn, I finally manage to capture a barcode, and it crashes!

Here's what it left on the console, hopefully it's useful to you:

Code:
<snip>
libdmtx_analyse_image(): done dmtxRegionFindNext
analyse_image() returned FALSE
In buffer_probe_callback
About to call analyse_image()
analyse_image(): no dmtx thread running
set image format
set image size
set image data
Extracting symbols :)
decoded UPC-A symbol "073149283085"
analyse_image() returned TRUE
first bit
Got a message from the GStreamer thread
Just finished processing barcode
process 11050: arguments to dbus_connection_send() were incorrect, assertion "connection != NULL" failed in file dbus-connection.c line 3003.
This is normally a bug in some application using the D-Bus library.
  D-Bus not built with -rdynamic so unable to print a backtrace
Aborted
-jkq
__________________
Class .. : Quiet One
Humor .. : [*********-] Alignment: Chaotic Good
Patience : [******----] Weapon(s): Python scripts
Agro ... : [***-------] Relic(s) : N900
 

The Following User Says Thank You to jkq For This Useful Post:
Posts: 2,102 | Thanked: 1,309 times | Joined on Sep 2006
#42
Ok, looks like some problem in my DBus signalling code (sending messages out to other interested apps). Does this happen all the time, for every barcode you scan and decode?

I'll look for and fix it this evening.

Thanks.
 
Posts: 2,102 | Thanked: 1,309 times | Joined on Sep 2006
#43
@jkq
I had mbarcode 0.0.4 (for Diablo) installed. Now it shows 0.0.6-3 available, but says it conflicts with zbar. It seems that your 'Conflicts' line worked.
There should be version 0.7.0-0 iirc, also you should be able to upgrade libzbar and it will remove the conflict with zbar.

@pandaboom
Also mbarcode seems to be unable to recognize barcodes on a curved surfaces (like a can).
The depth of field of the N900 camera is quite shallow, so barcodes on curved surfaces will appear out of focus. This isn't actually my doing, but something to look at with zbar (#zbar or http://zbar.sourceforge.net/), though once I get mbarcode in a more stable shape I will have a look at whether the detection algo can be improved for out-of-focus situations (compare and contrast with zbar's ability to detect out-of-focus QR codes, thanks to derf/tteribe).

I've just updated mbarcode from repo, rotation works fine, except one bug: captured image don't rotate with GUI.
The scan window is not double buffered, so its contents don't behave very well. I'll have a look at doing something here (copying the last frame and redrawing it, etc.), but is low priority for the time being.

python plugins (or callback) will be awesome and not so hard to code (IMO).
Plugins, as opposed to bindings, are probably quite challenging, though I was thinking of using e.g. Ethos as the plugin framework, which is able to do this.
 
Posts: 2,102 | Thanked: 1,309 times | Joined on Sep 2006
#44
So here is this barcode (cropped but not resized):
http://plasmon.rghost.ru/664032.image
mbarcode shows "0435281445", but the actual ISBN is 9780435281441.
Actually this is correct, it's the ISBN10 number which has been decoded behind the scenes and displayed for you. So this is my fault, I should given some indication that some processing was going on.
 
Posts: 2,102 | Thanked: 1,309 times | Joined on Sep 2006
#45
On a slightly different tack, talking about the structure of plugins:

Allow plugins in different languages. libethos allows C, Python and Vala iirc. Are there other plugin frameworks available that support multiple languages?

I will remove the text boxes from the front page of mbarcode, and just leave one larger one to display the raw barcode data.

Each plugin should have a callback which is called when barcode data is available; the plugins should be able to select the type of data they receive.

This could be very simple e.g. text data or numeric data, or mbarcode can do some pre-processing (which is my preference), so that it could be more like: text or ISBN13|10 or EAN (includes UPC) or other, so that a book plugin could just look for ISBNs and non-book plugins could ignore those, etc.

Types of plugins: some plugins will just provide a service but no UI, e.g. the standard text handler plugins (which do things like open vCards, URLS, emails, etc.) or the slightly more complex case of an AWS lookup plugin, which would need no GUI, but would also output data as well as accepting it. Any thoughts as to how to handle this?

Other plugins will have a GUI, e.g. my original target of a book db.

Perhaps the plugins-with-gui, should directly call the service-plugins such as AWS?

In terms of GUIs for gui-plugins, each plugin could be supplied with a container to which it can then write. Alternatively the plugin can return a container which it creates. I've seen both used, is there any advantage to one other the other?

Initially I was thinking of adding plugins to notebook tabs, but this is bad form in Fremantle, so perhaps they should have their own window (which makes their using menus easier too), and then they'll need a button or some other way of opening the plugin display window.

Anyway, those are some rough and meandering thoughts

Please let me know what you think.
 
Posts: 219 | Thanked: 94 times | Joined on Nov 2009 @ Helsinki, Finland
#46
Does anyone have an idea whether it's possible to integrate barcode reading with a web browser? The most amazing thing would be pay bills using online bank and read the necessary information from barcode.
 
Posts: 71 | Thanked: 49 times | Joined on Sep 2009 @ Espoo
#47
thanks for uploading a version to Extras-testing for us to try out.

Couple of comments/feature requests (let me know if these should go into Bugzilla instead):
- any way to stop the Camera app opening when i open the shutter to scan a code?
- some sort of Settings option for rotation (landscape, portrait or Automatic I guess are the obvious ones)

From an end user perspective i have to say that the Application feels a bit rough, but I think/guess from reading the posts here that is becuase you are doing all of the hard work of setting up correctly to be as useful as possible.
 
Posts: 2,102 | Thanked: 1,309 times | Joined on Sep 2006
#48
Does anyone have an idea whether it's possible to integrate barcode reading with a web browser? The most amazing thing would be pay bills using online bank and read the necessary information from barcode.
How does the barcode represent your payment info? It would certainly be possible to add a handler for a given barcode type (assuming it's decoded by zbar, try it and see) and have the N900 open the appropriate URL for you. Would that work?
 
Posts: 2,102 | Thanked: 1,309 times | Joined on Sep 2006
#49
thanks for uploading a version to Extras-testing for us to try out.
No probs, perhaps a bit too soon, but I thought people might like to see what I'm trying to do, and more ideas and feedback are always useful.

Couple of comments/feature requests (let me know if these should go into Bugzilla instead):
- any way to stop the Camera app opening when i open the shutter to scan a code?
I don't know about that, but if anyone does know please let me know as it's rather annoying Ideally a dialog asking which app you'd like to open could be displayed.

- some sort of Settings option for rotation (landscape, portrait or Automatic I guess are the obvious ones)
Yep, I guess that's a good idea.

From an end user perspective i have to say that the Application feels a bit rough, but I think/guess from reading the posts here that is becuase you are doing all of the hard work of setting up correctly to be as useful as possible.
Yeah, sorry it is a bit rough around the edges (and in the middle where webscraping comes into it) but I am trying to polish it up

I wonder if it would be worth using the bugtracker, otherwise I'm going to loose track of all the enhancement requests in here. Does mbarcode appear in there yet?
 
Posts: 3,319 | Thanked: 5,610 times | Joined on Aug 2008 @ Finland
#50
Originally Posted by lardman View Post
On a slightly different tack, talking about the structure of plugins:

Allow plugins in different languages. libethos allows C, Python and Vala iirc. Are there other plugin frameworks available that support multiple languages?
I know it's probably out of the scope of mbarcode, but Qt itself has some plugin/scripting oriented functionality. Out of the box you get C(++), Javascript, plus Python and Lua via extra libs (there might be others I don't know about).
__________________
Blogging about mobile linux - The Penguin Moves!
Maintainer of PyQt (see introduction and docs), AppWatch, QuickBrownFox, etc
 
Reply

Tags
barcode, camera, mbarcode


 
Forum Jump


All times are GMT. The time now is 22:20.