Instead of adapting the threshold to the image before executing
commands, adapt the threshold just before it is needed.
This allows to avoid theshold adaptation when -p, --process-only
is used with only the "grayscale" and/or "mirror" commands.
This also prepares the code to allow introduction of a new option
to avoid adapting the threshold to the original image before the
"crop" command is applied.
Both functions are always called with the same arguments.
Only the get_threshold() function is also called with
different x, y, w, h arguments (when used during dynamic
thresholding).
* The draw_pixel() function was called with an "image" parameter
of type "Imlib_Image" instead of "Imlib_Image *". This type
error did not result in a compilation error, and thus stayed
undetected in the code.
* Introduce a new function draw_color_pixel() similar to draw_pixel(),
and use it instead of repeatedly open-coding this operation.
This introduces a function to scan part of the image for foreground
pixels.
This scanline() function may be of use for distuingishing between
the digit '1' and the symbol ":".
It may also help in segment detection reliability if the "len" parameter
is used to skip scanning image areas between segment positions.
This relies on the definition of enum _imlib_load_error in Imlib2.h
and might break on different versions of Imlib2, but should be better
than the total lack of error reporting before.
Developed with Imlib2 version 1.4.5 from Debian/Sid:
$ dpkg -l libimlib2-dev
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name Version Architecture Description
+++-==============-============-============-=================================
ii libimlib2-dev 1.4.5-1 i386 Imlib2 development files
All calls to this function have been replaced by calls to make_mono()
with the appropriate luminance type (minimum, red, green, or blue).
This way --foreground / --background work with the commands
{r,g,b,rgb}_threshold as expected.
Problem was "shear" setting background pixels using the specified
--background color, but rgb_threshold() always using the default colors
(foreground black, background white), ognoring the options.
Added a formerly failing test case to the regression tests:
Lauro-LEDs-digits-fore_back
- no functional changes
- this is another step towards refactoring the recognition algorithm
- this is another step towards factoring out the image access routines to
ultimately replace Imlib2 by something else (e.g. gd)
Erik Auerswald