enhancing scanning time of 1picture

[polo]

Hi guys,
iam enjoyning theese forums and using it i was able to find solution to several problems which i encoutered while developing twain scaning app.

Now i got a real scanner kodak i1210 plus.
I was surprised when i realized that scanning 200dpi 8bit greyscale picture take 25s from the click of scan button to showing picture in picturebox on my form. (scanner ui is hidden)

I have done some tracing and found out that 3s takes the acquire operation which is
openDS
set capabilities
enableDS with guif

then 5 seconds takes transferding of picture to computer
which is
ImgInfo
ImgNativeTransfer
check pending xfer
and finaly reset it.

then 8 seconds takes closing ds
DisableDS
CloseDS

Question is why it takes 25seconds. I tried to scan white belt (only) in diferent dpi but the time didnt change.

Second question is if i can do anything to improve one picture scan performance. Iam avare of MemoryBuffered transfers and so on, but iam not sure if i can take advantage while scaning one picture. I guess that i can use compression in memory buffered mode but the time of picture transfer didnt change when i was playing with dpi resolution.

third question is why it takes 8seconds to closeDS, i guess its freeing used memory?

Have good time and thank you for reply.

[Catherine Sea]

Hi Polo,

Are you developing a desktop application or a web application? Did you try other applications, such as the Scanners & Cameras wizard comes with Windows? If so, how was that going?

__________________________
Catherine Sea
TWAIN .NET Component | TWAIN ActiveX/Plug-in

[polo]

Hi,
i did try it in twuck it took something about 15secs but i couldnt tell precisly becouse there is operation with the scanner gui, which is in my application disabled.

Iam developing a desktop application.

I was supprised by the fakt that dpi resolution didnt increase the time, that 200 and 240 dpi took the same time. Maybe higher resolution would alter the time i will test it.

Do you think that for example using compresion and memoryBuffered transfer could make things faster?

Thank you.

[fct]

I’ve worked with a 1220. Using memory buffered transfers with JPEG compression and so on will make transfers faster, but I don’t remember how much. It certainly helps in RGB images. You can test it yourself with twirl ( http://www.dosadi.com/twirl.htm ) and the Twain UI

The long closing time there probably has to do with the way their TWAIN driver works. I think it uses .NET and loads some heavy post-processing libraries that take some time to unload.

Didn’t seem solvable when I tested the 1220.

[AndLek]

Hi,

I would propose following for problem analysing and resolving
1) Try to scan in Buffered mode especially with compression and check if there is performance improvement
2) As a rule there is no difference between gray scanning and color but there is significant different between binary and gray/color scanning so try to scan page with binary color format
3) And I don’t think you will see different scanning with 200 DPI and 300 DPI, try to scan with 100 and 600 to see different.
4) Try to scan with virtual twain driver like TWAIN Importer ( http://www.scanworkssoftware.com/twainimporter.aspx ).
Do following steps:
– Enable logging in TWAIN Importer, it will allow you to see time of transferring and time for other operations
– Try to scan with your software
– Try to scan with other popular software, any evaluation version will be fine
– Compare results to determine if the reason of slowness is in your software or in TWAIN driver for 1220

Good luck :),
Andrew

[Author]

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