GdPicture Imaging SDK - Live Support Center

[senthil]

Hi loic,
When I am scanning a document using your sample(Twain scanning)
, Image is in black and white and the size is also smaller nearly 8kb.
But the clarity of the image is not good. (For example scan a photo)

oGdPicture.TwainSetCurrentResolution (200)
oGdPicture.TwainSetCurrentPixelType (TWPT_BW) 'BW
oGdPicture.TwainSetCurrentBitDepth (1) ' 1 bpp

To solve the clarity issue I used gray scalling to achieve the required
Clarity.But the file size is increased more than 200kb.

oGdPicture.TwainSetCurrentResolution (75)
oGdPicture.TwainSetCurrentPixelType (TWPT_GRAY) 'Gray
oGdPicture.TwainSetCurrentBitDepth (1) ' 1 bpp


Is there any way to scan and save the image in JPEG compression?
Please give me suggestion to achieve good clarity and smaller file size…

regards
senthil

[Loïc]

Hi Senthil,


There is not "best way". It depends of your image pixel data and image palette.

The SaveAsJpeg methods always saves the native image as 24 bpp bit depth.

If you want to save a 8bpp image with a small file size you can try that:

- PDF format (Flate compression)
- PNG format
- Tiff format with LZW compression.


All are using lossless compression.

Best regards,

Loïc