突然发现 下午无事可干了，心里慌得狠，总想找点事儿事情做。初学android，也是初学OpenGLES，想起自己的许多经验都是这个平台给予的，今天在这里也分享下一段自己整合的代码，如何使用OpenglES在android显示摄像头的滤镜效果，先贴出一篇前辈的帖子，主要用到了在Shader上yuv转RGB的显示。http://blog.csdn.net/eastlhu/article/details/9382431
前提
使用工具: android studio，android版本4.0，opengles2.0
思路：
使用opengles 绘制摄像头数据，并使用滤镜处理了摄像头的效果，GPU的绘制，减少cpu的占用
效果预览
前半部为摄像头采集数据，后半段为opengles 加香槟特效滤镜 绘制的数据
一、获取摄像头数据
通过调用android提供的Camera类，可以打开摄像头，并通过SurfaceView显示数据。在Camera类中，有一个
PreviewCallback 接口，用于接收Camera采集的yuv数据（手机采集的格式一般为yuv420sp），我自己写了一个摄像头采集的类，大致框架如下：
<pre name="code" class="java">// 摄像头数据采集及图层绘制
public class CameraView extends SurfaceView implements SurfaceHolder.Callback, Camera.PreviewCallback
{
// 源视频帧宽/高
private int srcFrameWidth = 640;
private int srcFrameHeight = 480;
// 数据采集
private int curCameraIndex = 1;
private Camera camera = null;
// 视频帧共享存储回调接口
private SurfaceHolder surfaceHolder;
public CameraView(Context context)
{
super(context);
if (Camera.getNumberOfCameras() > 1)
{
curCameraIndex = 1;
}
else
{
curCameraIndex = 0;
}
surfaceHolder = getHolder();
surfaceHolder.addCallback(this);
surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
@Override
public void surfaceCreated(SurfaceHolder sh)
{
stopCamera();
startCamera(curCameraIndex);
}
@Override
public void surfaceChanged(SurfaceHolder sh, int format, int width, int height)
{
}
@Override
public void surfaceDestroyed(SurfaceHolder sh)
{
stopCamera();
}
// 根据索引初始化摄像头
public void initCamera(int cameraIndex)
{
// 初始化并打开摄像头
if (camera == null)
{
try
{
camera = Camera.open(cameraIndex);
}
catch (Exception e)
{
return;
}
Camera.Parameters params = camera.getParameters();
if (params.getSupportedFocusModes().contains(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE))
{
// 自动对焦
params.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);
}
try
{
params.setPreviewFormat(ImageFormat.NV21);
params.setPreviewSize(srcFrameWidth, srcFrameHeight);
camera.setParameters(params);
params = camera.getParameters();
params.setPreviewFpsRange(15*1000, 30*1000);
camera.setParameters(params);
}
catch (Exception e)
{
}
try
{
camera.setPreviewDisplay(surfaceHolder);
}
catch(Exception ex)
{
ex.printStackTrace();
}
camera.startPreview();
camera.setPreviewCallback(this);
camera.setDisplayOrientation(180);
}
}
// 打开摄像头
private void startCamera(int cameraIndex)
{
initCamera(cameraIndex);
}
// 停止并释放摄像头
public void stopCamera()
{
if (camera != null)
{
camera.setPreviewCallback(null);
camera.stopPreview();
camera.release();
camera = null;
}
}
// 获取摄像头视频数据
@Override
public void onPreviewFrame(byte[] data, Camera camera)
{
synchronized (this)
{
}
}
}
二、Opengl绘制
在android开发中，摄像头数据的显示使用SurfaceView来完成任务，主要的绘制过程由底层API完成，opengles的绘制在SurfaceView做不了什么文章，那么，opengles绘制的数据，需要在哪里显示呢？ 如果不嫌麻烦，可以使用 view里的 Canvas（画布）将数据画出来。不过，android为我们专门提供了一个GLSurFaceView的类来更好的显示opengl绘制的数据，在GLSurFaceView中有一个Rederer渲染接口，主要绘制就在这个接口里操作。这个接口有三个方法需要实现，如下
<span style="font-size:18px;"> public class MyGL20Renderer implements GLSurfaceView.Renderer
{
@Override
public void onSurfaceCreated(GL10 unused, EGLConfig config)
{
}
@Override
public void onDrawFrame(GL10 unused)
{
}
@Override
public void onSurfaceChanged(GL10 unused, int width, int height)
{
}</span>
<span style="font-size:18px;"> }</span>
<span style="font-size:18px;"></span>三个方法一目了然，OnSurfaceCreate 用于初始化操作，例如为Opengl设置背景颜色，开启纹理绘制等；OnDrawFrame 用于具体的绘制操作；OnsurfaceChanged 在尺寸发生变化时调用的方法
在开始调用opengles绘制前，需要做的一些准备工作
1、判断手机是否支持opengles绘制，在androidManifest.xml中加入如下
<uses-feature android:glEsVersion="0x00020000" android:required="true" />
2、调用如下启动Opengles2.0的绘制；设置Renderer并设置绘制模式
setEGLContextClientVersion(2);//设置Renderer到GLSurfaceViewsetRenderer(new MyGL20Renderer());// 只有在绘制数据改变时才绘制viewsetRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
三、具体绘制细节（进入代码环节）
关于MainActivity如下
public class MainActivity extends Activity
{
private CameraGLSurfaceView mGLView = null;
private DrawYUVView mDrawView = null;
private CameraView cameraView = null;
private RelativeLayout previewLayout = null,GLpreviewLayout = null,DrawpreviewLayout;
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_main);
RelativeLayout.LayoutParams layoutParams = null;
//GL绘制窗口
GLpreviewLayout = (RelativeLayout)findViewById(R.id.GLpreviewLayout);
layoutParams = new RelativeLayout.LayoutParams(640,480);
mGLView = new CameraGLSurfaceView(this);
GLpreviewLayout.addView(mGLView, layoutParams);
//视频窗口
previewLayout = (RelativeLayout)findViewById(R.id.previewLayout);
layoutParams = new RelativeLayout.LayoutParams(640,480 );
cameraView = new CameraView(this);
cameraView.setSaveFrameCallback(mGLView);
previewLayout.addView(cameraView, layoutParams);
}
}
CameraGLSurfaceView 是我编写的一个类，继承自GLSurfaceView，所有opengles绘制操作，将在这个类里面完成。该类还继承了一个SaveFrameCallback接口，以回调函数的方式接收camera发送过来的数据，调用代码中的cameraView.SetSaveFrameCallback(mGLView)函数设置此回调函数
CameraGLSurfaceView
public class CameraGLSurfaceView extends GLSurfaceView implements CameraView.SaveFrameCallback
{
// 源视频帧宽/高
private int srcFrameWidth = 640;
private int srcFrameHeight = 480;
private int viewWidth = 0, viewHeight = 0;
private int frameWidth = 640, frameHeight = 480;
private ByteBuffer yBuf = null, uBuf = null, vBuf = null;
private int yuvFrameSize = 640*480;
// 纹理id
private int[] Ytexture = new int[1];
private int[] Utexture = new int[1];
private int[] Vtexture = new int[1];
private int[] Mtexture = new int[1];
private int aPositionMain = 0, aTexCoordMain = 0, uYTextureMain = 0, uUTextureMain = 0, uVTextureMain = 0,uMTextureMain = 0;
private int programHandleMain = 0;
private static final int FLOAT_SIZE_BYTES = 4;
private FloatBuffer squareVertices = null;
private FloatBuffer coordVertices = null;
private boolean mbpaly = false;
public CameraGLSurfaceView(Context context)
{
super(context);
setEGLContextClientVersion(2);
//设置Renderer到GLSurfaceView
setRenderer(new MyGL20Renderer());
// 只有在绘制数据改变时才绘制view
setRenderMode(GLSurfaceView.RENDERMODE_WHEN_DIRTY);
int qtrFrameSize = yuvFrameSize >> 2;
yBuf = ByteBuffer.allocateDirect(yuvFrameSize);
yBuf.order(ByteOrder.nativeOrder()).position(0);
uBuf = ByteBuffer.allocateDirect(qtrFrameSize);
uBuf.order(ByteOrder.nativeOrder()).position(0);
vBuf = ByteBuffer.allocateDirect(qtrFrameSize);
vBuf.order(ByteOrder.nativeOrder()).position(0);
// 顶点坐标
squareVertices = ByteBuffer.allocateDirect(util.squareVertices.length * FLOAT_SIZE_BYTES).order(ByteOrder.nativeOrder()).asFloatBuffer();
squareVertices.put(util.squareVertices).position(0);
//纹理坐标
coordVertices = ByteBuffer.allocateDirect(util.coordVertices.length * FLOAT_SIZE_BYTES).order(ByteOrder.nativeOrder()).asFloatBuffer();
coordVertices.put(util.coordVertices).position(0);
}
public class MyGL20Renderer implements GLSurfaceView.Renderer
{
public void onSurfaceCreated(GL10 unused, EGLConfig config)
{
mbpaly = false;
//设置背景的颜色
GLES20.glClearColor(0.5f, 0.5f, 0.5f, 1.0f);
//启动纹理
GLES20.glEnable(GLES20.GL_TEXTURE_2D);
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glActiveTexture(GLES20.GL_TEXTURE1);
GLES20.glActiveTexture(GLES20.GL_TEXTURE2);
GLES20.glActiveTexture(GLES20.GL_TEXTURE3);
changeFilterShader(0);
//创建yuv纹理
createTexture(frameWidth, frameHeight, GLES20.GL_LUMINANCE, Ytexture);
createTexture(frameWidth>>1, frameHeight>>1, GLES20.GL_LUMINANCE, Utexture);
createTexture(frameWidth >> 1, frameHeight >> 1, GLES20.GL_LUMINANCE, Vtexture);
createTexture(frameWidth, frameHeight, GLES20.GL_RGBA, Mtexture);
mbpaly = true;
}
private void changeFilterShader( int filterId )
{
programHandleMain = util.createShaderProgram();
if ( programHandleMain != -1 )
{
// 获取VertexShader变量
aPositionMain = getShaderHandle(programHandleMain, "vPosition");
aTexCoordMain = getShaderHandle(programHandleMain, "a_texCoord");
// 获取FrameShader变量
uYTextureMain = getShaderHandle(programHandleMain, "SamplerY");
uUTextureMain = getShaderHandle(programHandleMain, "SamplerU");
uVTextureMain = getShaderHandle(programHandleMain, "SamplerV");
uMTextureMain = getShaderHandle(programHandleMain, "SamplerM");
// 使用滤镜着色器程序
GLES20.glUseProgram(programHandleMain);
//给变量赋值
GLES20.glUniform1i(uYTextureMain, 0);
GLES20.glUniform1i(uUTextureMain, 1);
GLES20.glUniform1i(uVTextureMain, 2);
GLES20.glUniform1i(uMTextureMain, 3);
GLES20.glEnableVertexAttribArray(aPositionMain);
GLES20.glEnableVertexAttribArray(aTexCoordMain);
// 设置Vertex Shader数据
squareVertices.position(0);
GLES20.glVertexAttribPointer(aPositionMain, 2, GLES20.GL_FLOAT, false, 0, squareVertices);
coordVertices.position(0);
GLES20.glVertexAttribPointer(aTexCoordMain, 2, GLES20.GL_FLOAT, false, 0, coordVertices);
}
}
// 创建纹理
private void createTexture(int width, int height, int format, int[] textureId)
{
//创建纹理
GLES20.glGenTextures(1, textureId, 0);
//绑定纹理
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, textureId[0]);
//设置纹理属性
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S, GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T, GLES20.GL_CLAMP_TO_EDGE);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);
GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_LINEAR);
GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, format, width, height, 0, format, GLES20.GL_UNSIGNED_BYTE, null);
}
public void onDrawFrame(GL10 unused)
{
// 重绘背景色
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
if ( yBuf != null )
{
//y
GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, Ytexture[0]);
GLES20.glTexSubImage2D(GLES20.GL_TEXTURE_2D,
0,
0,
0,
frameWidth,
frameHeight,
GLES20.GL_LUMINANCE,
GLES20.GL_UNSIGNED_BYTE,
yBuf);
//u
GLES20.glActiveTexture(GLES20.GL_TEXTURE1);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, Utexture[0]);
GLES20.glTexSubImage2D(GLES20.GL_TEXTURE_2D,
0,
0,
0,
frameWidth >> 1,
frameHeight >> 1,
GLES20.GL_LUMINANCE,
GLES20.GL_UNSIGNED_BYTE,
uBuf);
//v
GLES20.glActiveTexture(GLES20.GL_TEXTURE2);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, Vtexture[0]);
GLES20.glTexSubImage2D(GLES20.GL_TEXTURE_2D,
0,
0,
0,
frameWidth >> 1,
frameHeight >> 1,
GLES20.GL_LUMINANCE,
GLES20.GL_UNSIGNED_BYTE,
vBuf);
//mark图层
GLES20.glActiveTexture(GLES20.GL_TEXTURE3);
GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, Mtexture[0]);
GLES20.glTexSubImage2D(GLES20.GL_TEXTURE_2D, 0, 0, 0, frameWidth, frameHeight, GLES20.GL_RGBA, GLES20.GL_UNSIGNED_BYTE, null);
}
//绘制
GLES20.glViewport(0, 0, viewWidth, viewHeight);
GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
}
public void onSurfaceChanged(GL10 unused, int width, int height)
{
viewWidth = width;
viewHeight = height;
GLES20.glViewport(0, 0, viewWidth, viewHeight);
}
}
public void onSaveFrames(byte[] data, int length)
{
if ( length != 0 && mbpaly )
{
yBuf.clear();
uBuf.clear();
vBuf.clear();
rotateYUV(data, srcFrameWidth, srcFrameHeight);
requestRender();
}
}
public int getShaderHandle(int programHandle,String name)
{
int handle = GLES20.glGetAttribLocation(programHandle, name);
if (handle == -1)
{
handle = GLES20.glGetUniformLocation(programHandle, name);
}
return handle;
}
public void rotateYUV(byte[] src,int width,int height)
{
byte [] yArray = new byte[yBuf.limit()];
byte [] uArray = new byte[uBuf.limit()];
byte [] vArray = new byte[vBuf.limit()];
int nFrameSize = width * height;
int k = 0;
int uvCount = nFrameSize>>1;
//取分量y值
for(int i = 0;i < height*width;i++ )
{
yArray[ k ] = src[ i ];
k++;
}
k = 0;
//取分量uv值
for( int i = 0;i < uvCount ;i+=2 )
{
vArray[ k ] = src[ nFrameSize + i ]; //v
uArray[ k ] = src[ nFrameSize + i + 1 ];//u
k++;
}
yBuf.put(yArray).position(0);
uBuf.put(uArray).position(0);
vBuf.put(vArray).position(0);
}
}
1、onSurfaceCreated
此函数只要操作为初始化一些opengles的工作，如，调用changeFilterShader 中， 创建VertexShader和FrameShader，获取相应的变量进行初始化赋值，并创建 yuv以及mark图层的纹理
2、rotateYUV()
此函数用户提取yuv的分量，如果有用户显示颜色值不对，将 取分量uv值 的循环体内，将uv位置调换试试；调用requestRender 绘制
VertexShader和FrameShader 代码
public static String VERTEX_SHADER =
"attribute vec4 vPosition; \n"+
"attribute vec2 a_texCoord; \n"+
"varying vec2 tc; \n"+
"void main() \n"+
"{ \n"+
" gl_Position = vPosition; \n"+
" tc = a_texCoord; \n"+
"} \n";
public static String FRAG_SHADER = "varying lowp vec2 tc; \n"+ "uniform sampler2D SamplerY;\n"+ "uniform sampler2D SamplerU;\n"+ "uniform sampler2D SamplerV;\n"+ "void main(void) \n"+ "{ \n"+ "mediump vec3 yuv; \n"+ "lowp vec3 rgb; \n"+ "yuv.x = texture2D(SamplerY, tc).r; \n"+ "yuv.y = texture2D(SamplerU, tc).r - 0.5;\n"+ "yuv.z = texture2D(SamplerV, tc).r - 0.5;\n"+ "rgb = mat3( 1,1,1,0,-0.39465,2.03211,1.13983,-0.58060,0) * yuv;\n"+ "gl_FragColor = vec4(rgb, 1);\n"+ "} \n";
基本上主要的绘制工作以及做完了，现在附上我的这个demo，由于本人csdn分数不是很多，所以下载需要点积分。
http://download.csdn.net/detail/chylove5/9240905