问题
I'm using twaindotnet to scan an image with 2400 DPI. Whenever I scan a full page in color I get a message that there is not enough memory to perform this action. I tried it on a different computer with around 4 GB of ram and got the same error message.
If I scan the image as black and white or gray-scale I don't get any error and everything is working fine.
Is that a problem that is related to the scanner driver (Canon 9000F) or is this a general TWAIN problem?
回答1:
Looks like that Twain library is scanning to memory, the Twain specification also has a file transfer mode which is generally used for very large images (ICAP_XFERMECH). Twaindotnet may allow you to choose the file transfer mode when scanning.
回答2:
gray-scale images have a bit depth varying from 2 to 8. for an image of legal size and of 2400 dpi, the size can be 163 MB ~ 654 MB.
color images have higher bit depth. take 32 for example, the image of the same size and dpi can be around 2.62 GB. plus the memory occupied by other applications, 4 GB memory likely runs out.
File Size = (height x width x bit depth x dpi2) / 8
- dpi2 means dpi square
来源：https://stackoverflow.com/questions/9277805/are-memory-issues-common-when-scanning-2400-dpi-pictures-with-twain