Hi there,
I am currently surveying different tools to test my first TWAIN driver/data source with. Before that, I have spent a few days with the TWAIN specification to be able to adhere to the spec as best as possible, and then tested my source against the sample App of the TWAIN group.
When I tried to use the source with Irfanview, my source was detected without problems, but was then surprised that there were no negotiation on capabilities taking place and especially that there was no DG_CONTROL / DAT_ENTRYPOINT / MSG_SET sent prior scanning. The latter is somewhat of an issue, because Irfanview immediately starts sending DG_CONTROL / DAT_CAPABILITY / MSG_SET with values when a scan is started, that cannot be locked to get a TW_ONEVALUE from... instead, in the case of the CAP_XFERMECH value, the handle being passed is just a regular TW_UINT16* to the actual value of TWSX_MEMFILE, instead of a TW_ONEVALUE containing that value in the Item-member.
The sample app from the TWAIN group as well as software like PaperScan do indeed set the entry point callback and pass a TW_ONEVALUE, as I would expect...
Is there some big optional way of handling the workflow/values or even the option to NOT use containers that I missed reading the spec? Or are there TWAIN conformity issues with Irfanview? I really cannot tell at the moment, since some other sources seems to work perfectly fine with Irfanview. That's the reason I am asking here directly, and I really hope someone can shed some light on that
If there are any question about all of this, please, ask away!
Cheers!
I am currently surveying different tools to test my first TWAIN driver/data source with. Before that, I have spent a few days with the TWAIN specification to be able to adhere to the spec as best as possible, and then tested my source against the sample App of the TWAIN group.
When I tried to use the source with Irfanview, my source was detected without problems, but was then surprised that there were no negotiation on capabilities taking place and especially that there was no DG_CONTROL / DAT_ENTRYPOINT / MSG_SET sent prior scanning. The latter is somewhat of an issue, because Irfanview immediately starts sending DG_CONTROL / DAT_CAPABILITY / MSG_SET with values when a scan is started, that cannot be locked to get a TW_ONEVALUE from... instead, in the case of the CAP_XFERMECH value, the handle being passed is just a regular TW_UINT16* to the actual value of TWSX_MEMFILE, instead of a TW_ONEVALUE containing that value in the Item-member.
The sample app from the TWAIN group as well as software like PaperScan do indeed set the entry point callback and pass a TW_ONEVALUE, as I would expect...
Is there some big optional way of handling the workflow/values or even the option to NOT use containers that I missed reading the spec? Or are there TWAIN conformity issues with Irfanview? I really cannot tell at the moment, since some other sources seems to work perfectly fine with Irfanview. That's the reason I am asking here directly, and I really hope someone can shed some light on that
If there are any question about all of this, please, ask away!
Cheers!
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