package com.enrique.stackblur;
import android.graphics.Bitmap;
import java.util.ArrayList;
import java.util.concurrent.Callable;
/**
* Blur using Java code.
* <p/>
* This is a compromise between Gaussian Blur and Box blur
* It creates much better looking blurs than Box Blur, but is
* 7x faster than my Gaussian Blur implementation.
* <p/>
* I called it Stack Blur because this describes best how this
* filter works internally: it creates a kind of moving stack
* of colors whilst scanning through the image. Thereby it
* just has to add one new block of color to the right side
* of the stack and remove the leftmost color. The remaining
* colors on the topmost layer of the stack are either added on
* or reduced by one, depending on if they are on the right or
* on the left side of the stack.
*
* @author Enrique López Mañas <eenriquelopez@gmail.com>
* http://www.neo-tech.es
* <p/>
* Author of the original algorithm: Mario Klingemann <mario.quasimondo.com>
* <p/>
* Based heavily on http://vitiy.info/Code/stackblur.cpp
* See http://vitiy.info/stackblur-algorithm-multi-threaded-blur-for-cpp/
* @copyright: Enrique López Mañas
* @license: Apache License 2.0
*/
class JavaBlurProcess implements BlurProcess {
private static final short[] stackblur_mul = {
512, 512, 456, 512, 328, 456, 335, 512, 405, 328, 271, 456, 388, 335, 292, 512,
454, 405, 364, 328, 298, 271, 496, 456, 420, 388, 360, 335, 312, 292, 273, 512,
482, 454, 428, 405, 383, 364, 345, 328, 312, 298, 284, 271, 259, 496, 475, 456,
437, 420, 404, 388, 374, 360, 347, 335, 323, 312, 302, 292, 282, 273, 265, 512,
497, 482, 468, 454, 441, 428, 417, 405, 394, 383, 373, 364, 354, 345, 337, 328,
320, 312, 305, 298, 291, 284, 278, 271, 265, 259, 507, 496, 485, 475, 465, 456,
446, 437, 428, 420, 412, 404, 396, 388, 381, 374, 367, 360, 354, 347, 341, 335,
329, 323, 318, 312, 307, 302, 297, 292, 287, 282, 278, 273, 269, 265, 261, 512,
505, 497, 489, 482, 475, 468, 461, 454, 447, 441, 435, 428, 422, 417, 411, 405,
399, 394, 389, 383, 378, 373, 368, 364, 359, 354, 350, 345, 341, 337, 332, 328,
324, 320, 316, 312, 309, 305, 301, 298, 294, 291, 287, 284, 281, 278, 274, 271,
268, 265, 262, 259, 257, 507, 501, 496, 491, 485, 480, 475, 470, 465, 460, 456,
451, 446, 442, 437, 433, 428, 424, 420, 416, 412, 408, 404, 400, 396, 392, 388,
385, 381, 377, 374, 370, 367, 363, 360, 357, 354, 350, 347, 344, 341, 338, 335,
332, 329, 326, 323, 320, 318, 315, 312, 310, 307, 304, 302, 299, 297, 294, 292,
289, 287, 285, 282, 280, 278, 275, 273, 271, 269, 267, 265, 263, 261, 259
};
private static final byte[] stackblur_shr = {
9, 11, 12, 13, 13, 14, 14, 15, 15, 15, 15, 16, 16, 16, 16, 17,
17, 17, 17, 17, 17, 17, 18, 18, 18, 18, 18, 18, 18, 18, 18, 19,
19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 19, 20, 20, 20,
20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 21,
21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 21,
21, 21, 21, 21, 21, 21, 21, 21, 21, 21, 22, 22, 22, 22, 22, 22,
22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22,
22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 22, 23,
23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23,
23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23,
23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23, 23,
23, 23, 23, 23, 23, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,
24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24
};
@Override
public Bitmap blur(Bitmap original, float radius) {
int w = original.getWidth();
int h = original.getHeight();
int[] currentPixels = new int[w * h];
original.getPixels(currentPixels, 0, w, 0, 0, w, h);
int cores = StackBlurManager.EXECUTOR_THREADS;
ArrayList<BlurTask> horizontal = new ArrayList<BlurTask>(cores);
ArrayList<BlurTask> vertical = new ArrayList<BlurTask>(cores);
for (int i = 0; i < cores; i++) {
horizontal.add(new BlurTask(currentPixels, w, h, (int) radius, cores, i, 1));
vertical.add(new BlurTask(currentPixels, w, h, (int) radius, cores, i, 2));
}
try {
StackBlurManager.EXECUTOR.invokeAll(horizontal);
} catch (InterruptedException e) {
return null;
}
try {
StackBlurManager.EXECUTOR.invokeAll(vertical);
} catch (InterruptedException e) {
return null;
}
return Bitmap.createBitmap(currentPixels, w, h, Bitmap.Config.ARGB_8888);
}
private static void blurIteration(int[] src, int w, int h, int radius, int cores, int core, int step) {
int x, y, xp, yp, i;
int sp;
int stack_start;
int stack_i;
int src_i;
int dst_i;
long sum_r, sum_g, sum_b,
sum_in_r, sum_in_g, sum_in_b,
sum_out_r, sum_out_g, sum_out_b;
int wm = w - 1;
int hm = h - 1;
int div = (radius * 2) + 1;
int mul_sum = stackblur_mul[radius];
byte shr_sum = stackblur_shr[radius];
int[] stack = new int[div];
if (step == 1) {
int minY = core * h / cores;
int maxY = (core + 1) * h / cores;
for (y = minY; y < maxY; y++) {
sum_r = sum_g = sum_b =
sum_in_r = sum_in_g = sum_in_b =
sum_out_r = sum_out_g = sum_out_b = 0;
src_i = w * y; // start of line (0,y)
for (i = 0; i <= radius; i++) {
stack_i = i;
stack[stack_i] = src[src_i];
sum_r += ((src[src_i] >>> 16) & 0xff) * (i + 1);
sum_g += ((src[src_i] >>> 8) & 0xff) * (i + 1);
sum_b += (src[src_i] & 0xff) * (i + 1);
sum_out_r += ((src[src_i] >>> 16) & 0xff);
sum_out_g += ((src[src_i] >>> 8) & 0xff);
sum_out_b += (src[src_i] & 0xff);
}
for (i = 1; i <= radius; i++) {
if (i <= wm) src_i += 1;
stack_i = i + radius;
stack[stack_i] = src[src_i];
sum_r += ((src[src_i] >>> 16) & 0xff) * (radius + 1 - i);
sum_g += ((src[src_i] >>> 8) & 0xff) * (radius + 1 - i);
sum_b += (src[src_i] & 0xff) * (radius + 1 - i);
sum_in_r += ((src[src_i] >>> 16) & 0xff);
sum_in_g += ((src[src_i] >>> 8) & 0xff);
sum_in_b += (src[src_i] & 0xff);
}
sp = radius;
xp = radius;
if (xp > wm) xp = wm;
src_i = xp + y * w; // img.pix_ptr(xp, y);
dst_i = y * w; // img.pix_ptr(0, y);
for (x = 0; x < w; x++) {
src[dst_i] = (int)
((src[dst_i] & 0xff000000) |
((((sum_r * mul_sum) >>> shr_sum) & 0xff) << 16) |
((((sum_g * mul_sum) >>> shr_sum) & 0xff) << 8) |
((((sum_b * mul_sum) >>> shr_sum) & 0xff)));
dst_i += 1;
sum_r -= sum_out_r;
sum_g -= sum_out_g;
sum_b -= sum_out_b;
stack_start = sp + div - radius;
if (stack_start >= div) stack_start -= div;
stack_i = stack_start;
sum_out_r -= ((stack[stack_i] >>> 16) & 0xff);
sum_out_g -= ((stack[stack_i] >>> 8) & 0xff);
sum_out_b -= (stack[stack_i] & 0xff);
if (xp < wm) {
src_i += 1;
++xp;
}
stack[stack_i] = src[src_i];
sum_in_r += ((src[src_i] >>> 16) & 0xff);
sum_in_g += ((src[src_i] >>> 8) & 0xff);
sum_in_b += (src[src_i] & 0xff);
sum_r += sum_in_r;
sum_g += sum_in_g;
sum_b += sum_in_b;
++sp;
if (sp >= div) sp = 0;
stack_i = sp;
sum_out_r += ((stack[stack_i] >>> 16) & 0xff);
sum_out_g += ((stack[stack_i] >>> 8) & 0xff);
sum_out_b += (stack[stack_i] & 0xff);
sum_in_r -= ((stack[stack_i] >>> 16) & 0xff);
sum_in_g -= ((stack[stack_i] >>> 8) & 0xff);
sum_in_b -= (stack[stack_i] & 0xff);
}
}
}
// step 2
else if (step == 2) {
int minX = core * w / cores;
int maxX = (core + 1) * w / cores;
for (x = minX; x < maxX; x++) {
sum_r = sum_g = sum_b =
sum_in_r = sum_in_g = sum_in_b =
sum_out_r = sum_out_g = sum_out_b = 0;
src_i = x; // x,0
for (i = 0; i <= radius; i++) {
stack_i = i;
stack[stack_i] = src[src_i];
sum_r += ((src[src_i] >>> 16) & 0xff) * (i + 1);
sum_g += ((src[src_i] >>> 8) & 0xff) * (i + 1);
sum_b += (src[src_i] & 0xff) * (i + 1);
sum_out_r += ((src[src_i] >>> 16) & 0xff);
sum_out_g += ((src[src_i] >>> 8) & 0xff);
sum_out_b += (src[src_i] & 0xff);
}
for (i = 1; i <= radius; i++) {
if (i <= hm) src_i += w; // +stride
stack_i = i + radius;
stack[stack_i] = src[src_i];
sum_r += ((src[src_i] >>> 16) & 0xff) * (radius + 1 - i);
sum_g += ((src[src_i] >>> 8) & 0xff) * (radius + 1 - i);
sum_b += (src[src_i] & 0xff) * (radius + 1 - i);
sum_in_r += ((src[src_i] >>> 16) & 0xff);
sum_in_g += ((src[src_i] >>> 8) & 0xff);
sum_in_b += (src[src_i] & 0xff);
}
sp = radius;
yp = radius;
if (yp > hm) yp = hm;
src_i = x + yp * w; // img.pix_ptr(x, yp);
dst_i = x; // img.pix_ptr(x, 0);
for (y = 0; y < h; y++) {
src[dst_i] = (int)
((src[dst_i] & 0xff000000) |
((((sum_r * mul_sum) >>> shr_sum) & 0xff) << 16) |
((((sum_g * mul_sum) >>> shr_sum) & 0xff) << 8) |
((((sum_b * mul_sum) >>> shr_sum) & 0xff)));
dst_i += w;
sum_r -= sum_out_r;
sum_g -= sum_out_g;
sum_b -= sum_out_b;
stack_start = sp + div - radius;
if (stack_start >= div) stack_start -= div;
stack_i = stack_start;
sum_out_r -= ((stack[stack_i] >>> 16) & 0xff);
sum_out_g -= ((stack[stack_i] >>> 8) & 0xff);
sum_out_b -= (stack[stack_i] & 0xff);
if (yp < hm) {
src_i += w; // stride
++yp;
}
stack[stack_i] = src[src_i];
sum_in_r += ((src[src_i] >>> 16) & 0xff);
sum_in_g += ((src[src_i] >>> 8) & 0xff);
sum_in_b += (src[src_i] & 0xff);
sum_r += sum_in_r;
sum_g += sum_in_g;
sum_b += sum_in_b;
++sp;
if (sp >= div) sp = 0;
stack_i = sp;
sum_out_r += ((stack[stack_i] >>> 16) & 0xff);
sum_out_g += ((stack[stack_i] >>> 8) & 0xff);
sum_out_b += (stack[stack_i] & 0xff);
sum_in_r -= ((stack[stack_i] >>> 16) & 0xff);
sum_in_g -= ((stack[stack_i] >>> 8) & 0xff);
sum_in_b -= (stack[stack_i] & 0xff);
}
}
}
}
private static class BlurTask implements Callable<Void> {
private final int[] _src;
private final int _w;
private final int _h;
private final int _radius;
private final int _totalCores;
private final int _coreIndex;
private final int _round;
public BlurTask(int[] src, int w, int h, int radius, int totalCores, int coreIndex, int round) {
_src = src;
_w = w;
_h = h;
_radius = radius;
_totalCores = totalCores;
_coreIndex = coreIndex;
_round = round;
}
@Override
public Void call() throws Exception {
blurIteration(_src, _w, _h, _radius, _totalCores, _coreIndex, _round);
return null;
}
}
}