
Thread
2003.07.11 19:22 "grey scale conversion", by Christopher Thomas
Hello all,
Newbie questions here, thanks for your patience.
Setup:
----------
Windows/VS6
I'm using tifflib to open G4fax images (decoding each scanline using TIFFReadScanline)
Then I'm memcopying each decoded scanline output from TIFFReadScanline and appending to a large 1 dimensional buffer.
Then I'm calling createbitmap and pointing that to my large buffer to display on screen.
Problem:
- Above works but is much slower than the Kodak/Wang "Imaging" program found on Windows.
- Any ideas how they do it?
- Any faster calls to decode the entire image?
- Any faster calls to display the image?
- Can anyone point me to some sample C/C++ code that BLT's to screen?
- When I go to make proxies (scaling of the image) I'd like the option of scaling in greyscale. (Kodak/Wang Imaging does this almost instantly) How can I do this on my large uncompressed buffer of B&W 1 bit data? Is there a tifflib call that will perform greyscale scaling?
- Thanks very much for your time.
Chris Thomas
cthomas@inversemedia.com