Closed LizhuWeng closed 4 years ago
Hi LizhuWeng,
Can you provide a log of the events when you use the USB Camera? The DTWDEMO32.exe has a logging option in the menu.
Thanks.
Edit: If possible, if you build the source, and put a breakpoint on this line:
You can step into that function to see what is being done when DTWAIN_OpenSource is called.
Hi, This's the log file: dtwain.log
The process of DTWDEMO32.exe can only be closed from the System Task Manager after that.
Edit: Since the laptop is not my develop environment, I 'll try to debug the code when available.
From the attached log, you're getting an error code from the Source Manager when attempting to query the ICAP_PIXELTYPE capability for the camera. Here is a snippet from the log (at the tail end):
TW_MEMREF is TW_CAPABILITY:
{
Cap=ICAP_PIXELTYPE
ContainerType=TW_ONEVALUE
hContainer=00000000
}
[2020-01-18 09:11:00.5428651]Output: return code from DSM=1039 (Unknown TWAIN Condition Code)
DSM_Entry(pSource=00825870H, pDest=00833BC4H, DG_CONTROL, DAT_CAPABILITY, MSG_QUERYSUPPORT, TW_MEMREF=0042B9B4H) called
Decoded pSource:
{
Id=153
Version Number=1.0
Version Language=13
Version Country=1
Version Info=<?>
ProtocolMajor=1
ProtocolMinor=9
SupportedGroups= DG_CONTROL, DG_IMAGE, DG_AUDIO
Manufact
Then the log stops right there. Note the output return code is 1039. There is no 1039 return code defined by the current TWAIN specification that I am aware of. Thus the problem at first glance seems to be a TWAIN Source driver issue when attempting to query your camera for the pixel types it supports.
The driver information is here (also found in the log):
{
Id=154
Version Number=1.0
Version Language=13
Version Country=1
Version Info=JULY, 2003
ProtocolMajor=1
ProtocolMinor=7
SupportedGroups= DG_CONTROL, DG_IMAGE
Manufacturer=SONIX
Product Family=TWAIN
Product Name=USB Video Device
}
So your webcam is using the SONIX driver. I would try and see if there is an update to this driver. If so, install it (please get the driver from SONIX, not a no-name website), install it, and see if this corrects the issue.
Closing issue.
Hi, Thanks for your great work firstly!
I found an issue that the twain_library maybe stuck sometimes, which makes the main thread has no response:
Happens when using DTWAIN_OpenSource API for the source like USB Camera of my laptop (Which can be get by using DTWAIN_EnumSources API),I tested with DTWDEMO32.exe
It also happens when in paper jam. already handled the message by the callback function DTWAIN_DE_PAPERJAM
I also had set the timeout by using DTWAIN_SetTwainTimeout API, but seems not work.
So how to handle the timeout issue properly when the Twain library block , any advice? Thanks!