#7 Delphi Binding

[Anonymous]

Attached is Delphi codes to bind ZBar dll. Please add to Language section

[Anonymous]

你好，我来自中国，我需要你的帮助！
Hello, I come from China, I need your help!

[spadix]

I have a few review comments that need to be addressed before I include this:

* Is this your original work that you're releasing under the LGPL?

* For consistency with other interfaces, the initial-cap prefix of the library should be "ZBar", not "Zbar"

* What is the purpose of the ZBAR_BARCODES array? What additional functionality is introduced over zbar_get_symbol_name? This list should at least be populated using zbar_get_symbol_name, to avoid introducing inconsistencies.

* The ZBarBarcode procedure is too tightly integrated with application specifics to be included with the library. I suggest splitting out the reusable functionality and removing the monolithic API. eg, a function to read a TIFF file and return a ZBarImage would be a useful addition.

There are also a few areas I would like to see enhanced, if not now, then in a future patch:

* I am unable to compile these bindings with FPC - is this expected? I am loathe to unnecessarily require a specific proprietary compiler (note that FPC did compile after some quick hacking...)

* These bindings introduce Windows specific calls, unnecessarily tying the cross-platform library to a specific platform. A few compiler directives should fix this.

* The ZBar library uses an object oriented design. Given the availability of object oriented Pascal, it would make sense if the OOP layer was also ported

* It would be nice if we had a basic test case to verify that the compiled unit is functional

Thanks for contributing this!

[franky]

I have a working example, although I had to modify the code a bit
(basically, I don't have the DLL96V1, DLLSP96 the author put in the uses clause, so I've had to remove the following methods from the unit:

function zbar_image_scanner_parse_config
function zbar_decoder_parse_config
procedure ZbarBarcode

)
But it stil has a problem I couldn't solve: I get an access violation error when destroying the image in the function 'zbar_image_free_data'

Here is the code, compiled in Borland Delphi 7 Studio and ready to run. Hope it serves you well: http://www.mediafire.com/?addn2zzydmj
If by any chance you find why I get the access violation error, please, let me know.

[DimensionSlider]

DLL96V1, DLLSP96 come from ImageLib Corporate Suite. Just get the lib.

[franky]

All right, problem solved, I did not set the cleanup function in the zbar_image_set_data, I freed the data from the stream object instead.

I still get a minor memory leak when reading QR codes(as far as I know, there are no leaks with EAN-13 or with no code at all), and i'm almost sure it's a bug in the library.

Here's the code:
http://www.mediafire.com/?zdva4zowmzl
same as below, but better :D

[spadix]

Thanks c4pu110. I have not yet been able to run your example, I will try again later.

btw- do you have the experience to update the bindings as described below so I can include this in the library? If I have to make the changes myself, it's going to be awhile before I can get to it...

> memory leak when reading QR codes

This bug is fixed in hg (rev a27e17b2bdd3). Fix should be available with the next release

[Nobody/Anonymous]

I'll give it a try, but I can't promise anything (less than 3 months of experience with Delphi, and mainly as a bugfixer).
btw, these libraries are better than the commercial stuff I've tried until now, good work!

[SourceForge Robot]

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