openGL ES進階教程（六）美顏濾鏡之美白，磨皮，紅潤
阿新 • • 發佈：2019-02-13
網上搜羅了一堆的美顏濾鏡效果，可惜盡不如人意。最後偶然看到ios上提供了一個用OC寫的美顏濾鏡，好吧，改寫成Java的試試。好在大學時期搞過一段時間IOS開發，用自己的半吊子的水平，沒想到還真改成功了。
先上效果圖：
網上搜漲痘痘的圖片，搜到劉濤了，罪過罪過~
原圖：
美顏後：
可見有四個可滑動的bar，從上到下分別是，磨皮度，磨皮值，美白，紅潤。
美顏原理
磨皮：本質就是讓畫素點模糊，可以使用高斯模糊，但是可能導致邊緣會不清晰，用雙邊濾波(Bilateral Filter) ，有針對性的模糊畫素點，能保證邊緣不被模糊。 美白：本質就是提高亮度。 紅潤：本質就是改變色調。
下面是濾鏡原始碼：
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.opengl.GLES20;
import android.opengl.GLSurfaceView;
import android.opengl.Matrix;
import android.view.WindowManager;
import com.ws.gl.opengltexture.programs.TextureShaderProgram;
import 使用：
import android.opengl.GLSurfaceView;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.SeekBar;
import com.ws.gl.opengltexture.util.GLBitmapUtils;
import com.ws.ijk.openglpicture.R;
public class BeautyActivity extends AppCompatActivity implements SeekBar.OnSeekBarChangeListener {
private GLSurfaceView glSurfaceView;
private BeautyRenderer mRenderer;
private ImageView mImageView;
private Button startBtn,saveBtn;
private boolean isStart=true;
private SeekBar sb_step,sb_tone,sb_beauty,sb_bright;
private static float minstepoffset= -10;
private static float maxstepoffset= 10;
private static float minToneValue= -5;
private static float maxToneValue= 5;
private static float minbeautyValue= 0;
private static float maxbeautyValue= 2.5f;
private static float minbrightValue= 0;
private static float maxbrightValue= 1;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_beauty);
glSurfaceView= (GLSurfaceView) findViewById(R.id.glView);
glSurfaceView.setEGLContextClientVersion(2);
mRenderer =new BeautyRenderer(this);
glSurfaceView.setRenderer(mRenderer);
glSurfaceView.setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
mImageView= (ImageView) findViewById(R.id.image);
mImageView.setImageResource(R.mipmap.liu);
startBtn = (Button) findViewById(R.id.startbtn);
startBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if(isStart){
mImageView.setVisibility(View.GONE);
}else {
mImageView.setVisibility(View.VISIBLE);
}
isStart = !isStart;
}
});
saveBtn = (Button) findViewById(R.id.picBtn);
saveBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
mRenderer.saveImage();
glSurfaceView.requestRender();
}
});
initView();
}
private void initView() {
sb_step = (SeekBar) findViewById(R.id.sb_step);
sb_step.setOnSeekBarChangeListener(this);
sb_tone = (SeekBar) findViewById(R.id.sb_tone);
sb_tone.setOnSeekBarChangeListener(this);
sb_beauty = (SeekBar) findViewById(R.id.sb_beauty);
sb_beauty.setOnSeekBarChangeListener(this);
sb_bright = (SeekBar) findViewById(R.id.sb_bright);
sb_bright.setOnSeekBarChangeListener(this);
}
@Override
protected void onPause() {
super.onPause();
glSurfaceView.onPause();
}
@Override
protected void onResume() {
super.onResume();
glSurfaceView.onResume();
}
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean b) {
switch (seekBar.getId()){
case R.id.sb_step:
mRenderer.setTexelOffset(range(progress,minstepoffset,maxstepoffset));
break;
case R.id.sb_tone:
mRenderer.setToneLevel(range(progress,minToneValue,maxToneValue));
break;
case R.id.sb_beauty:
mRenderer.setBeautyLevel(range(progress,minbeautyValue,maxbeautyValue));
break;
case R.id.sb_bright:
mRenderer.setBrightLevel(range(progress,minbrightValue,maxbrightValue));
break;
}
glSurfaceView.requestRender();
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
protected float range(final int percentage, final float start, final float end) {
return (end - start) * percentage / 100.0f + start;
}
}