I would like to take a picture in true black and white in my app. I searched for solutions (in this site too), but I always found solution to put a photo in gray scale (for example in this topic), but it's not what I am looking for ...
I also found a topic proposing this :
public static Bitmap createContrast(Bitmap src, double value) {
// image size
int width = src.getWidth();
int height = src.getHeight();
// create output bitmap
Bitmap bmOut = Bitmap.createBitmap(width, height, src.getConfig());
// color information
int A, R, G, B;
int pixel;
// get contrast value
double contrast = Math.pow((100 + value) / 100, 2);
// scan through all pixels
for (int x = 0; x < width; ++x) {
for (int y = 0; y < height; ++y) {
// get pixel color
pixel = src.getPixel(x, y);
A = Color.alpha(pixel);
// apply filter contrast for every channel R, G, B
R = Color.red(pixel);
R = (int) (((((R / 255.0) - 0.5) * contrast) + 0.5) * 255.0);
if (R < 0) {
R = 0;
} else if (R > 255) {
R = 255;
}
G = Color.red(pixel);
G = (int) (((((G / 255.0) - 0.5) * contrast) + 0.5) * 255.0);
if (G < 0) {
G = 0;
} else if (G > 255) {
G = 255;
}
B = Color.red(pixel);
B = (int) (((((B / 255.0) - 0.5) * contrast) + 0.5) * 255.0);
if (B < 0) {
B = 0;
} else if (B > 255) {
B = 255;
}
// set new pixel color to output bitmap
bmOut.setPixel(x, y, Color.argb(A, R, G, B));
}
}
return bmOut;
}
But the image quality is horrible ...
Is anyone having an idea please?
Thank you
If you like the image to be 1bit black/white you can use a simple (& slow) threshold algorithm
public static Bitmap createBlackAndWhite(Bitmap src) {
int width = src.getWidth();
int height = src.getHeight();
// create output bitmap
Bitmap bmOut = Bitmap.createBitmap(width, height, src.getConfig());
// color information
int A, R, G, B;
int pixel;
// scan through all pixels
for (int x = 0; x < width; ++x) {
for (int y = 0; y < height; ++y) {
// get pixel color
pixel = src.getPixel(x, y);
A = Color.alpha(pixel);
R = Color.red(pixel);
G = Color.green(pixel);
B = Color.blue(pixel);
int gray = (int) (0.2989 * R + 0.5870 * G + 0.1140 * B);
// use 128 as threshold, above -> white, below -> black
if (gray > 128)
gray = 255;
else
gray = 0;
// set new pixel color to output bitmap
bmOut.setPixel(x, y, Color.argb(A, gray, gray, gray));
}
}
return bmOut;
}
But depending on what that will not look good, for better results you need a dithering algorithm, see Algorithm overview - this one is the threshold method.
For 256 levels of gray conversion:
according to http://www.mathworks.de/help/toolbox/images/ref/rgb2gray.html you calculate the gray value of each pixel as gray = 0.2989 * R + 0.5870 * G + 0.1140 * B which would translate to
public static Bitmap createGrayscale(Bitmap src) {
int width = src.getWidth();
int height = src.getHeight();
// create output bitmap
Bitmap bmOut = Bitmap.createBitmap(width, height, src.getConfig());
// color information
int A, R, G, B;
int pixel;
// scan through all pixels
for (int x = 0; x < width; ++x) {
for (int y = 0; y < height; ++y) {
// get pixel color
pixel = src.getPixel(x, y);
A = Color.alpha(pixel);
R = Color.red(pixel);
G = Color.green(pixel);
B = Color.blue(pixel);
int gray = (int) (0.2989 * R + 0.5870 * G + 0.1140 * B);
// set new pixel color to output bitmap
bmOut.setPixel(x, y, Color.argb(A, gray, gray, gray));
}
}
return bmOut;
}
But that is pretty slow since you have to do that for millions of pixels separately.
https://stackoverflow.com/a/9377943/995891 has a much nicer way of achieving the same.
// code from that answer put into method from above
public static Bitmap createGrayscale(Bitmap src) {
int width = src.getWidth();
int height = src.getHeight();
Bitmap bmOut = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bmOut);
ColorMatrix ma = new ColorMatrix();
ma.setSaturation(0);
Paint paint = new Paint();
paint.setColorFilter(new ColorMatrixColorFilter(ma));
canvas.drawBitmap(src, 0, 0, paint);
return bmOut;
}
G = Color.red(pixel);
G = Color.green(pixel);
B = Color.red(pixel);
B = Color.blue(pixel);
See if this changes (in bold) helps.
Related
I have a code that turns a RGB bitmap into a bitmap of black and white colors, using this code:
public static Bitmap setDefaultValues(Bitmap bmp) {
Mat srcMat = new Mat();
org.opencv.android.Utils.bitmapToMat(bmp, srcMat, true);
final Bitmap bitmap = Bitmap.createBitmap(srcMat.clone().width(), srcMat.clone().height(), Bitmap.Config.ARGB_8888);
Imgproc.cvtColor(srcMat, srcMat, Imgproc.COLOR_BGR2GRAY, 0);
Mat srcMat1 = srcMat;
Imgproc.GaussianBlur(srcMat1, srcMat1, new Size(3, 3), 0);
//Mat srcMat1 = new Mat(srcMat.rows(), srcMat.cols(), CV_8UC1);
//int kernalsize = 3;
//Imgproc.bilateralFilter(srcMat, srcMat1, kernalsize, kernalsize * 2, kernalsize / 2);
srcMat1.convertTo(srcMat1, 0, 1.9, -120);
srcMat1.convertTo(srcMat1, CvType.CV_8U, 1.9, -120);
Imgproc.cvtColor(srcMat1, srcMat1, Imgproc.COLOR_GRAY2RGBA, 4);
org.opencv.android.Utils.matToBitmap(srcMat, bitmap, true);
return bitmap;
}
I have implement this code for convert RGB image into black and white.
this is return me as right, but my question is here i cant remove shadow from image.
also i have compare other application this is convert perfectly, i don't understand where i am wrong.
this is original Image :
this is my application output
this is other application output
So please help me how can i achieve my goal.
Please use following code for convert your color image to black and white.
public static Bitmap createContrast(Bitmap src, double value) {
// image size
int width = src.getWidth();
int height = src.getHeight();
// create output bitmap
Bitmap bmOut = Bitmap.createBitmap(width, height, src.getConfig());
// color information
int A, R, G, B;
int pixel;
// get contrast value
double contrast = Math.pow((100 + value) / 100, 2);
// scan through all pixels
for(int x = 0; x < width; ++x) {
for(int y = 0; y < height; ++y) {
// get pixel color
pixel = src.getPixel(x, y);
A = Color.alpha(pixel);
// apply filter contrast for every channel R, G, B
R = Color.red(pixel);
R = (int)(((((R / 255.0) - 0.5) * contrast) + 0.5) * 255.0);
if(R < 0) { R = 0; }
else if(R > 255) { R = 255; }
G = Color.red(pixel);
G = (int)(((((G / 255.0) - 0.5) * contrast) + 0.5) * 255.0);
if(G < 0) { G = 0; }
else if(G > 255) { G = 255; }
B = Color.red(pixel);
B = (int)(((((B / 255.0) - 0.5) * contrast) + 0.5) * 255.0);
if(B < 0) { B = 0; }
else if(B > 255) { B = 255; }
// set new pixel color to output bitmap
bmOut.setPixel(x, y, Color.argb(A, R, G, B));
}
}
return bmOut;}
Please try this if you will get the solution
public static Bitmap test(Bitmap src){
int width = src.getWidth();
int height = src.getHeight();
// create output bitmap
Bitmap bmOut = Bitmap.createBitmap(width, height, src.getConfig());
// color information
int A, R, G, B;
int pixel;
for (int x = 0; x < width; ++x) {
for (int y = 0; y < height; ++y) {
// get pixel color
pixel = src.getPixel(x, y);
A = Color.alpha(pixel);
R = Color.red(pixel);
G = Color.green(pixel);
B = Color.blue(pixel);
int gray = (int) (0.2989 * R + 0.5870 * G + 0.1140 * B);
// use 128 as threshold, above -> white, below -> black
if (gray > 128) {
gray = 255;
}
else{
gray = 0;
}
// set new pixel color to output bitmap
bmOut.setPixel(x, y, Color.argb(A, gray, gray, gray));
}
}
return bmOut;
}
Please see the answer on this thread. He has explained and provide a good result in output.
#Threshold image using opencv (Java)
I am trying to write a function that overlays an image at a rectangle with transparency over top of another image, However it doesn't layer the images it just erases the section that I overlay and the transparency cuts through the entire image. Here is my code.
public static void overlayImage(String imagePath, String overlayPath, int x, int y, int width, int height) {
Mat overlay = Imgcodecs.imread(overlayPath, Imgcodecs.IMREAD_UNCHANGED);
Mat image = Imgcodecs.imread(imagePath, Imgcodecs.IMREAD_UNCHANGED);
Rectangle rect = new Rectangle(x, y, width, height);
Imgproc.resize(overlay, overlay, rect.size());
Mat submat = image.submat(new Rect(rect.x, rect.y, overlay.cols(), overlay.rows()));
overlay.copyTo(submat);
Imgcodecs.imwrite(imagePath, image);
}
EDIT: Here are some example pictures:
Before:
After:
Found this function that does exactly what I needed.
public static void overlayImage(Mat background,Mat foreground,Mat output, Point location){
background.copyTo(output);
for(int y = (int) Math.max(location.y , 0); y < background.rows(); ++y){
int fY = (int) (y - location.y);
if(fY >= foreground.rows())
break;
for(int x = (int) Math.max(location.x, 0); x < background.cols(); ++x){
int fX = (int) (x - location.x);
if(fX >= foreground.cols()){
break;
}
double opacity;
double[] finalPixelValue = new double[4];
opacity = foreground.get(fY , fX)[3];
finalPixelValue[0] = background.get(y, x)[0];
finalPixelValue[1] = background.get(y, x)[1];
finalPixelValue[2] = background.get(y, x)[2];
finalPixelValue[3] = background.get(y, x)[3];
for(int c = 0; c < output.channels(); ++c){
if(opacity > 0){
double foregroundPx = foreground.get(fY, fX)[c];
double backgroundPx = background.get(y, x)[c];
float fOpacity = (float) (opacity / 255);
finalPixelValue[c] = ((backgroundPx * ( 1.0 - fOpacity)) + (foregroundPx * fOpacity));
if(c==3){
finalPixelValue[c] = foreground.get(fY,fX)[3];
}
}
}
output.put(y, x,finalPixelValue);
}
}
}
Is there any way to convert a Bitmap to sepia?
I know to convert to grayScale is to set the setSaturation in ColorMatrix.
But what about Sepia?
If you have instance of image then you can use ColorMartix to draw it in Sepia. Let me describe way how you can do this using Drawable.
public static void setSepiaColorFilter(Drawable drawable) {
if (drawable == null)
return;
final ColorMatrix matrixA = new ColorMatrix();
// making image B&W
matrixA.setSaturation(0);
final ColorMatrix matrixB = new ColorMatrix();
// applying scales for RGB color values
matrixB.setScale(1f, .95f, .82f, 1.0f);
matrixA.setConcat(matrixB, matrixA);
final ColorMatrixColorFilter filter = new ColorMatrixColorFilter(matrixA);
drawable.setColorFilter(filter);
}
Sample project was moved from Bitbucket to GitHub. Please check Release section to download APK binary to test without compiling.
I know the answer, but maybe if some have other better solution..
public Bitmap toSephia(Bitmap bmpOriginal)
{
int width, height, r,g, b, c, gry;
height = bmpOriginal.getHeight();
width = bmpOriginal.getWidth();
int depth = 20;
Bitmap bmpSephia = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(bmpSephia);
Paint paint = new Paint();
ColorMatrix cm = new ColorMatrix();
cm.setScale(.3f, .3f, .3f, 1.0f);
ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);
paint.setColorFilter(f);
canvas.drawBitmap(bmpOriginal, 0, 0, paint);
for(int x=0; x < width; x++) {
for(int y=0; y < height; y++) {
c = bmpOriginal.getPixel(x, y);
r = Color.red(c);
g = Color.green(c);
b = Color.blue(c);
gry = (r + g + b) / 3;
r = g = b = gry;
r = r + (depth * 2);
g = g + depth;
if(r > 255) {
r = 255;
}
if(g > 255) {
g = 255;
}
bmpSephia.setPixel(x, y, Color.rgb(r, g, b));
}
}
return bmpSephia;
}
I've improved on the OP's answer. This runs competitively fast when compared to the ColorMatrix method, but producing a nicer brown tone. (in my opinion)
public Bitmap toSepiaNice(Bitmap color) {
int red, green, blue, pixel, gry;
int height = color.getHeight();
int width = color.getWidth();
int depth = 20;
Bitmap sepia = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
int[] pixels = new int[width * height];
color.getPixels(pixels, 0, width, 0, 0, width, height);
for (int i = 0; i < pixels.length; i++) {
pixel = pixels[i];
red = (pixel >> 16) & 0xFF;
green = (pixel >> 8) & 0xFF;
blue = pixel & 0xFF;
red = green = blue = (red + green + blue) / 3;
red += (depth * 2);
green += depth;
if (red > 255)
red = 255;
if (green > 255)
green = 255;
pixels[i] = (0xFF << 24) | (red << 16) | (green << 8) | blue;
}
sepia.setPixels(pixels, 0, width, 0, 0, width, height);
return sepia;
}
Please suggest me How to apply photo effects/filters on Run time in android Camera? with out using JNI , OpenGl and open CV. I need to apply effects only through Java code.
Step 1. Convert frame from NV21 to format supported by some image processing library. You can read how to do it here or here
Step 2. Use image processing library to perform filtering. For example you can use ImageJ. You can read about how to use ImageJ here or here or here.
Check out the Image Processing to apply various effects on Image. It provides various effects to be applied on Image after capturing.
Suppose i want to apply contrast effect on image then i will use the below method:
public static Bitmap createContrast(Bitmap src, double value) {
// image size
int width = src.getWidth();
int height = src.getHeight();
// create output bitmap
Bitmap bmOut = Bitmap.createBitmap(width, height, src.getConfig());
// color information
int A, R, G, B;
int pixel;
// get contrast value
double contrast = Math.pow((100 + value) / 100, 2);
// scan through all pixels
for(int x = 0; x < width; ++x) {
for(int y = 0; y < height; ++y) {
// get pixel color
pixel = src.getPixel(x, y);
A = Color.alpha(pixel);
// apply filter contrast for every channel R, G, B
R = Color.red(pixel);
R = (int)(((((R / 255.0) - 0.5) * contrast) + 0.5) * 255.0);
if(R < 0) { R = 0; }
else if(R > 255) { R = 255; }
G = Color.red(pixel);
G = (int)(((((G / 255.0) - 0.5) * contrast) + 0.5) * 255.0);
if(G < 0) { G = 0; }
else if(G > 255) { G = 255; }
B = Color.red(pixel);
B = (int)(((((B / 255.0) - 0.5) * contrast) + 0.5) * 255.0);
if(B < 0) { B = 0; }
else if(B > 255) { B = 255; }
// set new pixel color to output bitmap
bmOut.setPixel(x, y, Color.argb(A, R, G, B));
}
}
// return final image
return bmOut;
}
Use above method as:
BitMap bmp =BitmapFactory.decodeByteArray(byteArray, 0, byteArray.length); //Here you can define your image and convert it into Bitmap.
bmp = createContrast(bm,75);
mImageView.setImageBitmap(bmp);
I have two bitmaps topBitmap and bottomBitmap and I need to blend the two bitmaps using color dodge in android. I could not find color dodge in PorterDuffXfermode. Is there any way to do it with ot without the use of a Canvas?
Kindly let me know how to blend two bitmaps using color dodge mode in android.Thanks in advance.
Hi I found this method from somewhere in SO post. This method takes two image and create one image using color dodge
public Bitmap ColorDodgeBlend(Bitmap source, Bitmap layer) {
Bitmap base = source.copy(Config.ARGB_8888, true);
Bitmap blend = layer.copy(Config.ARGB_8888, false);
IntBuffer buffBase = IntBuffer.allocate(base.getWidth() * base.getHeight());
base.copyPixelsToBuffer(buffBase);
buffBase.rewind();
IntBuffer buffBlend = IntBuffer.allocate(blend.getWidth() * blend.getHeight());
blend.copyPixelsToBuffer(buffBlend);
buffBlend.rewind();
IntBuffer buffOut = IntBuffer.allocate(base.getWidth() * base.getHeight());
buffOut.rewind();
while (buffOut.position() < buffOut.limit()) {
int filterInt = buffBlend.get();
int srcInt = buffBase.get();
int redValueFilter = Color.red(filterInt);
int greenValueFilter = Color.green(filterInt);
int blueValueFilter = Color.blue(filterInt);
int redValueSrc = Color.red(srcInt);
int greenValueSrc = Color.green(srcInt);
int blueValueSrc = Color.blue(srcInt);
int redValueFinal = colordodge(redValueFilter, redValueSrc);
int greenValueFinal = colordodge(greenValueFilter, greenValueSrc);
int blueValueFinal = colordodge(blueValueFilter, blueValueSrc);
int pixel = Color.argb(255, redValueFinal, greenValueFinal, blueValueFinal);
buffOut.put(pixel);
}
buffOut.rewind();
base.copyPixelsFromBuffer(buffOut);
blend.recycle();
return base;
}
here is the method do get the color dodge for pixel to get the effect
private int colordodge(int in1, int in2) {
float image = (float)in2;
float mask = (float)in1;
return ((int) ((image == 255) ? image:Math.min(255, (((long)mask << 8 ) / (255 - image)))));
}
I am trying to create sketch image of original photo, using this method I am able to create cartoonifying the image in color full format but I need in black and white pencil sketch format. If you have any idea then please share it.
hope this methods are useful to you
Put this code for pencil sketch ,this work for me
public Bitmap Changetosketch(Bitmap bmp) {
Bitmap Copy, Invert, Result;
Copy = toGrayscale(bmp);
Invert = createInvertedBitmap(Copy);
Invert = Blur.blur(this, Invert);
Result = ColorDodgeBlend(Invert, Copy);
return Result;
}
public static Bitmap toGrayscale(Bitmap src)
{
final double GS_RED = 0.299;
final double GS_GREEN = 0.587;
final double GS_BLUE = 0.114;
// create output bitmap
Bitmap bmOut = Bitmap.createBitmap(src.getWidth(), src.getHeight(), src.getConfig());
// pixel information
int A, R, G, B;
int pixel;
// get image size
int width = src.getWidth();
int height = src.getHeight();
// scan through every single pixel
for (int x = 0; x < width; ++x) {
for (int y = 0; y < height; ++y) {
// get one pixel color
pixel = src.getPixel(x, y);
// retrieve color of all channels
A = Color.alpha(pixel);
R = Color.red(pixel);
G = Color.green(pixel);
B = Color.blue(pixel);
// take conversion up to one single value
R = G = B = (int) (GS_RED * R + GS_GREEN * G + GS_BLUE * B);
// set new pixel color to output bitmap
bmOut.setPixel(x, y, Color.argb(A, R, G, B));
}
}
// return final image
return bmOut;
}
public static Bitmap createInvertedBitmap(Bitmap src) {
Bitmap bmOut = Bitmap.createBitmap(src.getWidth(), src.getHeight(), src.getConfig());
// color info
int A, R, G, B;
int pixelColor;
// image size
int height = src.getHeight();
int width = src.getWidth();
// scan through every pixel
for (int y = 0; y < height; y++) {
for (int x = 0; x < width; x++) {
// get one pixel
pixelColor = src.getPixel(x, y);
// saving alpha channel
A = Color.alpha(pixelColor);
// inverting byte for each R/G/B channel
R = 255 - Color.red(pixelColor);
G = 255 - Color.green(pixelColor);
B = 255 - Color.blue(pixelColor);
// set newly-inverted pixel to output image
bmOut.setPixel(x, y, Color.argb(A, R, G, B));
}
}
return bmOut;
}
public Bitmap ColorDodgeBlend(Bitmap source, Bitmap layer) {
Bitmap base = source.copy(Bitmap.Config.ARGB_8888, true);
Bitmap blend = layer.copy(Bitmap.Config.ARGB_8888, false);
IntBuffer buffBase = IntBuffer.allocate(base.getWidth() * base.getHeight());
base.copyPixelsToBuffer(buffBase);
buffBase.rewind();
IntBuffer buffBlend = IntBuffer.allocate(blend.getWidth() * blend.getHeight());
blend.copyPixelsToBuffer(buffBlend);
buffBlend.rewind();
IntBuffer buffOut = IntBuffer.allocate(base.getWidth() * base.getHeight());
buffOut.rewind();
while (buffOut.position() < buffOut.limit()) {
int filterInt = buffBlend.get();
int srcInt = buffBase.get();
int redValueFilter = Color.red(filterInt);
int greenValueFilter = Color.green(filterInt);
int blueValueFilter = Color.blue(filterInt);
int redValueSrc = Color.red(srcInt);
int greenValueSrc = Color.green(srcInt);
int blueValueSrc = Color.blue(srcInt);
int redValueFinal = colordodge(redValueFilter, redValueSrc);
int greenValueFinal = colordodge(greenValueFilter, greenValueSrc);
int blueValueFinal = colordodge(blueValueFilter, blueValueSrc);
int pixel = Color.argb(255, redValueFinal, greenValueFinal, blueValueFinal);
buffOut.put(pixel);
}
buffOut.rewind();
base.copyPixelsFromBuffer(buffOut);
blend.recycle();
return base;
}
private int colordodge(int in1, int in2) {
float image = (float)in2;
float mask = (float)in1;
return ((int) ((image == 255) ? image:Math.min(255, (((long)mask << 8 ) / (255 - image)))));
}