Home › Forums › TWAIN Classic › Twain Driver Settings for JPG
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Hi,
I am having a strange issue and need more information about twain….I’m hoping to attain some guidance here.
I use a small document management system called netDMS (http://www.vistasg.com/netdms_index/netdms_index.html).
We use canon scanners (DR 5010 and DR 4010) with the latest twain drivers from Canon’s website.
We recently purchased new PC’s that run windows 7 SP1 x64. All PC’s were previously running XP x86.
The problem is this:
On several of the new pcs, any image scanned into the document mgt system are being saved as JPG. The norm is for the images to be saved as tiff. The scanning functions of the dms simply calls the twain driver. It doesn’t give the users the option to choose a file format, nor is it configurable….according to the vendor, file format is controlled by the twain driver. The problem that i have with JPG is that the files are much larger then tiff. Also, we have a web service that converts the images on the fly when viewed on our website….the larger file sizes crash the pdf conversion. I have scowered thru the twain driver settings and can’t find anything that is relative.
Can anyone give me some guidance as to how to control this in the twain driver?
Thanks in advance.ICAP_COMPRESSION is the capability that controls the use of JPEG. Setting it to TWCP_NONE (no compression) should take care of that problem.
There’s a remote possiblity that the new driver is automatically detecting color content and is returning JPEG as a “convenience”.
I recommend downloading the TWACKER, which is a standalone application that can be used to tinker with TWAIN drivers. You can find it at the bottom of this page…
http://twain.org/scannerdriverdevelopers/specification-and-tools.htmlSee if the driver is automatically JPEG when you bring it up. Check the ICAP_COMPRESSION setting. You may also want to bring up the driver’s GUI to see if it has any settings that relate to your problem. Some drivers remember their GUI settings, so turning it off in the driver GUI and then running from your preferred application might give the result you want.
You should also consider contacting Canon for more help…
MarkM,
Thanks for your response. I have downloaded TWACK, but i can’t seem to find the “ICAP_COMPRESSION” setting that you referred to. Can you tell me where exactly i can find that?@MarkM wrote:
See if the driver is automatically JPEG when you bring it up. Check the ICAP_COMPRESSION setting.
Do you mean the driver gui that appears when scanning? Or is there a file somewhere that holds these settings? I have scowered thru every tab in the scanner driver gui (from twack and my 3rd party tool) and there aren’t any settings that relate to anything about JPEG or ICAP_COMPRESSION.
@MarkM wrote:
You should also consider contacting Canon for more help…
also tried this…they said that there aren’t any settings within the scanner driver that would automatically determine file format…..which i find hard to believe because i have several pcs without this problem and they are identical (same PC hw, same OS, same OS patch level, same scanner model, same scanner driver version ,same firmware, etc).
Okay…so when you have TWACKER up, you want to use “File / Select Source…” to pick your scanner.
Then click on “Special / 1 Load/Open SM”, then “Special / 2 Open Source”
Then click on “Special / 3 Send…”, and you’ll get the negotiation dialog…
It should already be set for DG_CONTROL / DAT_CAPABILITY / MSG_GET, so click on the “Capability:” dropdown and see if ICAP_CAPABILITY shows up in the list. If it does, then you can investigate it and make sure it’s set to TWCP_NONE. If it doesn’t, then keep going…
Are you using DAT_IMAGEFILEXFER to get the image? If so, then you need to look into the setting on ICAP_IMAGEFILEFORMAT and make sure that DAT_SETUPFILEXFER isn’t asking for TWFF_JFIF (the offical name of a JPEG header). Try setting it to TWFF_BMP.
If that doesn’t help, then make sure the scanner has a piece of paper ready, click on “File / Message Level / Full”, then click on “Special / 5 Enable/Transfer”
You’ll get a dialog for the DAT_IMAGEINFO command. Check the value of compression. If it’s anything other than 0, then the image was compressed by the driver. (6 is the value for JPEG)
Hopefully, that’ll give you some more information to figure out what’s happening…
Hi, MarkM.
I am almost a greenhand on JPEG processing problem. But I believe it can work better with the help of some professional TWAIN driver. I am testing about the related projects these days. Do you have any ideas about it? Or any good suggestion? Thanks in advance.Best regards,
ArronWe’ve tried all of the suggestions in this thread and have never been able to fix this problem….please update this thread if anyone has any work arounds…..it would be greatly appreciated!
TWAIN scanner is an industrial standard that was defined by the TWAIN Working Group. It includes the specification, data source manager and sample code. TWAIN links applications and image acquisition devices (such as photo scanners and digital cameras). The supportable acquired image of TWAIN scanner can be in various form, inlcuding jpg. For scanning and decoing different image format, we neen to do some modification on twain scanning console properties.
@Foximage wrote:
TWAIN scanner is an industrial standard that was defined by the TWAIN Working Group. It includes the specification, data source manager and sample code. TWAIN links applications and image acquisition devices (such as photo scanners and digital cameras). The supportable acquired image of TWAIN scanner can be in various form, inlcuding jpg. For scanning and decoing different image format, we neen to do some modification on twain scanning console properties.
So are you saying that the TWAIN Working Group needs to address this with a development effort? Or are you saying that there is a way to change this behavior thru a configuration setting? I am an end user / administrator so I am hoping that it is the latter. Can you clarify?
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