mirror of
https://github.com/opencv/opencv.git
synced 2024-11-25 03:30:34 +08:00
103 lines
2.7 KiB
Python
Executable File
103 lines
2.7 KiB
Python
Executable File
#!/usr/bin/python
|
|
from opencv.cv import *
|
|
from opencv.highgui import *
|
|
import sys
|
|
|
|
file_name = "../c/baboon.jpg";
|
|
|
|
_brightness = 100
|
|
_contrast = 100
|
|
Gbrightness = 100
|
|
Gcontrast = 100
|
|
|
|
hist_size = 64
|
|
range_0=[0,256]
|
|
ranges = [ range_0 ]
|
|
src_image=None
|
|
dst_image=None
|
|
hist_image=None
|
|
hist=None
|
|
lut=cvCreateMat(256,1,CV_8U)
|
|
|
|
# brightness/contrast callback function
|
|
def update_brightness( val ):
|
|
global Gbrightness # global tag is required, or we get UnboundLocalError
|
|
Gbrightness = val
|
|
update_brightcont( )
|
|
|
|
def update_contrast( val ):
|
|
global Gcontrast # global tag is required, or we get UnboundLocalError
|
|
Gcontrast = val
|
|
update_brightcont( )
|
|
|
|
def update_brightcont():
|
|
# no global tag required for images ???
|
|
|
|
brightness = Gbrightness - 100;
|
|
contrast = Gcontrast - 100;
|
|
max_value = 0;
|
|
|
|
# The algorithm is by Werner D. Streidt
|
|
# (http://visca.com/ffactory/archives/5-99/msg00021.html)
|
|
if( contrast > 0 ):
|
|
delta = 127.*contrast/100;
|
|
a = 255./(255. - delta*2);
|
|
b = a*(brightness - delta);
|
|
else:
|
|
delta = -128.*contrast/100;
|
|
a = (256.-delta*2)/255.;
|
|
b = a*brightness + delta;
|
|
|
|
for i in range(256):
|
|
v = cvRound(a*i + b);
|
|
if( v < 0 ):
|
|
v = 0;
|
|
if( v > 255 ):
|
|
v = 255;
|
|
lut[i] = v;
|
|
|
|
cvLUT( src_image, dst_image, lut );
|
|
cvShowImage( "image", dst_image );
|
|
|
|
cvCalcHist( dst_image, hist, 0, None );
|
|
cvZero( dst_image );
|
|
min_value, max_value = cvGetMinMaxHistValue( hist );
|
|
cvScale( hist.bins, hist.bins, float(hist_image.height)/max_value, 0 );
|
|
#cvNormalizeHist( hist, 1000 );
|
|
|
|
cvSet( hist_image, cvScalarAll(255));
|
|
bin_w = cvRound(float(hist_image.width)/hist_size);
|
|
|
|
for i in range(hist_size):
|
|
cvRectangle( hist_image, cvPoint(i*bin_w, hist_image.height),
|
|
cvPoint((i+1)*bin_w, hist_image.height - cvRound(cvGetReal1D(hist.bins,i))),
|
|
cvScalarAll(0), -1, 8, 0 );
|
|
|
|
cvShowImage( "histogram", hist_image );
|
|
|
|
|
|
if __name__ == "__main__":
|
|
# Load the source image. HighGUI use.
|
|
if len(sys.argv)>1:
|
|
file_name = sys.argv[1]
|
|
|
|
src_image = cvLoadImage( file_name, 0 );
|
|
|
|
if not src_image:
|
|
print "Image was not loaded.";
|
|
sys.exit(-1)
|
|
|
|
|
|
dst_image = cvCloneImage(src_image);
|
|
hist_image = cvCreateImage(cvSize(320,200), 8, 1);
|
|
hist = cvCreateHist([hist_size], CV_HIST_ARRAY, ranges, 1);
|
|
|
|
cvNamedWindow("image", 0);
|
|
cvNamedWindow("histogram", 0);
|
|
|
|
cvCreateTrackbar("brightness", "image", _brightness, 200, update_brightness);
|
|
cvCreateTrackbar("contrast", "image", _contrast, 200, update_contrast);
|
|
|
|
update_brightcont();
|
|
cvWaitKey(0);
|