//-----------------------------------------------------------------------------
// Description:
// This example shows how to scale the value channel of an image. This is
// a potential way to implement an auto-contrast/auto-levels operation
//-----------------------------------------------------------------------------
void LevelScalingWithClipping()
{
CHistLib Histogram;
// Open the image
Mat ImageLowContrast = imread("images/fiveShadesLowContrast.png");
assert(!ImageLowContrast.empty());
Mat ImageLowContrastClipped;
// Perform the normalized clipping procedure
double clipPercent = 50;
Histogram.NormalizeClipImageBGR(ImageLowContrast, ImageLowContrastClipped, clipPercent);
Mat HistImageLowContrastClipped;
Histogram.ComputeAndDrawHistogramValue(ImageLowContrastClipped, HistImageLowContrastClipped);
// Save the modified image
string ImageLowContrastClippedName("fiveShadesLowContrastClipped.value.png");
if (imwrite(ImageLowContrastClippedName, ImageLowContrastClipped))
{
cout << "Created clipped image: " << ImageLowContrastClippedName << endl;
}
// Save the histogram image
string HistImageLowContrastClippedName("fiveShadesLowContrastClipped.value.hist.png");
if (imwrite(HistImageLowContrastClippedName, HistImageLowContrastClipped))
{
cout << "Created value histogram: " << HistImageLowContrastClippedName << endl;
}
}
//-----------------------------------------------------------------------------
// Description:
// This examples draws an ascending ramp such that each histogram bar is
// separated by one pixel. The bars are colored red, the background is a
// light shade of grey and the axis is black. The height is chosen to fit the
// height of the bars (if the height is too small the bars will simply get
// cropped).
//-----------------------------------------------------------------------------
void DrawManuallyHistogram()
{
// Declare histlib instance
CHistLib Histogram;
// Customize the display properties
Histogram.SetPlotColor(Scalar(0x00, 0x00, 0xff));
Histogram.SetAxisColor(Scalar(0x00, 0x00, 0x00));
Histogram.SetBackgroundColor(Scalar(0xee, 0xee, 0xee));
Histogram.SetHistImageHeight(133);
Histogram.SetDrawSpreadOut(true);
// Create a row vector for histogram values
Mat Hist = Mat(128, 1, CV_32S);
// The ith bin gets i
for (int i = 0; i < Hist.rows; i++)
{
Hist.at<int>(i,0) = i;
}
Mat HistImage;
Histogram.DrawHistogram(Hist, HistImage);
string ImageName("ramp.hist.png");
if (imwrite(ImageName, HistImage))
{
cout << "Created single channel histogram: " << ImageName << endl;
}
}
void draw_Histogram(const cv::Mat &src_im, cv::Mat &hist_im){
//use filitchp made libraly
//github : "https://github.com/filitchp/opencv-histlib"
//
//引数 -> 入力画像，ヒストグラム用のMat型
cv::Mat dst;
if(src_im.channels() == 1) cv::cvtColor(src_im, dst, CV_GRAY2BGR);
else src_im.copyTo(dst);
CHistLib *Histogram = new CHistLib;
cv::MatND HistB, HistG, HistR;
Histogram->ComputeHistogramBGR(dst, HistB, HistG, HistR);
Histogram->DrawHistogramBGR(HistB, HistG, HistR, hist_im);
delete Histogram;
}
//-----------------------------------------------------------------------------
// Description:
// This example shows how to scale the value channel of an image. This is
// a potential way to implement an auto-contrast/auto-levels operation
//-----------------------------------------------------------------------------
void LevelScalingLowContrast()
{
CHistLib Histogram;
// Open the image
Mat ImageLowContrast = imread("images/fiveShadesLowContrast.png");
assert(!ImageLowContrast.empty());
Mat ImageOriginalNorm;
Mat ImageLowContrastNorm;
// Generate color histogram for the current image
Mat HistImageGray;
Histogram.NormalizeImageBGR(ImageLowContrast, ImageLowContrastNorm);
Mat HistImageLowContrast;
Mat HistImageLowContrastNorm;
Histogram.ComputeAndDrawHistogramValue(ImageLowContrast, HistImageLowContrast);
Histogram.ComputeAndDrawHistogramValue(ImageLowContrastNorm, HistImageLowContrastNorm);
// Save the histogram images
string HistImageLowContrastName("fiveShadesLowContrast.value.hist.png");
string HistImageLowContrastNormName("fiveShadesLowContrastNorm.value.hist.png");
string ImageLowContrastNormName("fiveShadesLowContrastNorm.png");
if (imwrite(HistImageLowContrastName, HistImageLowContrast))
{
cout << "Created value histogram: " << HistImageLowContrastName << endl;
}
if (imwrite(HistImageLowContrastNormName, HistImageLowContrastNorm))
{
cout << "Created value histogram: " << HistImageLowContrastNormName << endl;
}
if (imwrite(ImageLowContrastNormName, ImageLowContrastNorm))
{
cout << "Created normalized image: " << ImageLowContrastNormName << endl;
}
}
//-----------------------------------------------------------------------------
// Description:
// This example draws a value histogram from a test image.
//-----------------------------------------------------------------------------
void DrawSimpleValueHistogram()
{
CHistLib Histogram;
// Open the image
Mat ImageBGR = imread("images/bars.png");
assert(!ImageBGR.empty());
// Generate color histogram for the current image
Mat HistImageGray;
Histogram.ComputeAndDrawHistogramValue(ImageBGR, HistImageGray);
// Save the histogram image
string ImageName("bars.value.hist.png");
if (imwrite(ImageName, HistImageGray))
{
cout << "Created value histogram: " << ImageName << endl;
}
}
//-----------------------------------------------------------------------------
// Description:
// This example draws a color histogram from a test image.
// Note:
// At first the large spike at zero might seem unintuitive, but it's there
// because each channel has many pixels with the absence of color (0 values).
// For example, if you had an image that was just blue, the red and green
// channels would have lots of zeros and you would see a similar spike in at
// zero in this type of histogram plot.
//-----------------------------------------------------------------------------
void DrawSimpleBgrHistogram()
{
CHistLib Histogram;
// Open the image
Mat ImageBGR = imread("images/bars.png");
assert(!ImageBGR.empty());
// Generate histogram for the current image
Mat HistImageBGR;
Histogram.ComputeAndDrawHistogramBGR(ImageBGR, HistImageBGR);
// Save the histogram image
string ImageName("bars.rgb.hist.png");
if (imwrite(ImageName, HistImageBGR))
{
cout << "Created BGR histogram: " << ImageName << endl;
}
}
//-----------------------------------------------------------------------------
// Description:
// This example draws a value histogram from a photo. It is broken up into
// two steps to show how get access to the histogram vector
//-----------------------------------------------------------------------------
void DrawPhotoValueHistogram()
{
CHistLib Histogram;
// Open the image
Mat ImageBGR = imread("images/sunset.jpg");
assert(!ImageBGR.empty());
// Generate value channel histogram for the current image
Mat HistImageGray;
MatND Hist;
Histogram.ComputeHistogramValue(ImageBGR, Hist);
Histogram.DrawHistogramValue(Hist, HistImageGray);
// Save the histogram image
string ImageName("sunset.gray.hist.png");
if (imwrite(ImageName, HistImageGray))
{
cout << "Created value histogram: " << ImageName << endl;
}
}
//-----------------------------------------------------------------------------
// Description:
// This example shows how to scale the value channel of an image. This is
// a potential way to implement an auto-contrast/auto-levels operation
//-----------------------------------------------------------------------------
void LevelScalingNoEffect()
{
CHistLib Histogram;
// Open the image
Mat ImageOriginal = imread("images/fiveShades.png");
assert(!ImageOriginal.empty());
Mat ImageOriginalNorm;
// Generate color histogram for the current image
Mat HistImageGray;
// Used to verify that this operation does not modify the original image
Histogram.NormalizeImageBGR(ImageOriginal, ImageOriginalNorm);
Mat HistImageOriginal;
Mat HistImageOriginalNorm;
Histogram.ComputeAndDrawHistogramValue(ImageOriginal, HistImageOriginal);
Histogram.ComputeAndDrawHistogramValue(ImageOriginalNorm, HistImageOriginalNorm);
// Save the histogram images
string HistImageOriginalName("fiveShades.value.hist.png");
string HistImageOriginalNormName("fiveShadesNorm.value.hist.png");
if (imwrite(HistImageOriginalName, HistImageOriginal))
{
cout << "Created value histogram: " << HistImageOriginalName << endl;
}
if (imwrite(HistImageOriginalNormName, HistImageOriginalNorm))
{
cout << "Created value histogram: " << HistImageOriginalNormName << endl;
}
}
//-----------------------------------------------------------------------------
// Description:
// This example draws a color histogram from a photo. It is broken up into
// two steps to show how get access to the histogram vectors
//-----------------------------------------------------------------------------
void DrawPhotoBgrHistogram()
{
CHistLib Histogram;
// Open the image
Mat ImageBGR = imread("images/sunset.jpg");
assert(!ImageBGR.empty());
// Generate a color channel (BGR) histogram
Mat HistImageBGR;
MatND HistB;
MatND HistG;
MatND HistR;
Histogram.ComputeHistogramBGR(ImageBGR, HistB, HistG, HistR);
Histogram.DrawHistogramBGR(HistB, HistG, HistR, HistImageBGR);
// Save the histogram image
string ImageName("sunset.bgr.hist.png");
if (imwrite(ImageName, HistImageBGR))
{
cout << "Created BGR histogram: " << ImageName << endl;
}
}
