楼主收到这样的任务，在Android上用OpenGLES来显示YUV图像，之所以这样做，是因为：
1.Android本身也不能直接显示YUV图像，YUV转成RGB还是必要的；
2.YUV手动转RGB会占用大量的CPU资源，如果以这样的形式播放视频，手机会很热，所以我们尽量让GPU来做这件事；
3.OpenGLES是Android集成到自身框架里的第三方库，它有很多的可取之处。
博主的C/C++不是很好，所以整个过程是在Java层实现的，大家见笑，我主要参考（但不限于）以下文章，十分感谢这些朋友的分享：
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一、首先我先说一下这个解决方案是怎么运行的，给大家一个概念
1.显示在哪 -> GLSurfaceVIew
2.谁来把数据贴到GLSurfaceVIew上 -> Renderer
3.谁来负责YUV数据转换成RGB -> GL中的Program/Shader
一句话说明白就是：GL的Program/Shader把用户传过来的YUV数据，转换成RGB数据后，通过Renderer贴在GLSurfaceView上。
二、怎么检查你的手机是不是支持GLES2.0呢，使用下面的代码段就行了：
public static boolean detectOpenGLES20(Context context) {ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);ConfigurationInfo info = am.getDeviceConfigurationInfo();return (info.reqGlEsVersion >= 0x20000);}一般的手机，都是会支持GLES2.0的，大家不必担心。
三、开搞
A 先要有一个GLSurfaceView，把它放入你的布局中就好了。
找到这个家伙，对它进行简单的设置，并为它设置一个Renderer。
Renderer的作用就是在GLSurfaceView上画出图像。
mGLSurface = (GLFrameSurface) findViewById(R.id.glsurface);mGLSurface.setEGLContextClientVersion(2);mGLFRenderer = new GLFrameRenderer(this, mGLSurface);mGLSurface.setRenderer(mGLFRenderer);B 再就是看下GLFrameRenderer怎么来写了public class GLFrameRenderer implements Renderer {private ISimplePlayer mParentAct; //请无视之private GLSurfaceView mTargetSurface;private GLProgram prog = new GLProgram(0);private int mVideoWidth = -1, mVideoHeight = -1;private ByteBuffer y;private ByteBuffer u;private ByteBuffer v;public GLFrameRenderer(ISimplePlayer callback, GLSurfaceView surface) {mParentAct = callback; //请无视之mTargetSurface = surface;}@Overridepublic void onSurfaceCreated(GL10 gl, EGLConfig config) {Utils.LOGD("GLFrameRenderer :: onSurfaceCreated");if (!prog.isProgramBuilt()) {prog.buildProgram();Utils.LOGD("GLFrameRenderer :: buildProgram done");}}@Overridepublic void onSurfaceChanged(GL10 gl, int width, int height) {Utils.LOGD("GLFrameRenderer :: onSurfaceChanged");GLES20.glViewport(0, 0, width, height);}@Overridepublic void onDrawFrame(GL10 gl) {synchronized (this) {if (y != null) {// reset position, have to be doney.position(0);u.position(0);v.position(0);prog.buildTextures(y, u, v, mVideoWidth, mVideoHeight);GLES20.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);prog.drawFrame();}}}/*** this method will be called from native code, it happens when the video is about to play or* the video size changes.*/public void update(int w, int h) {Utils.LOGD("INIT E");if (w > 0 && h > 0) {if (w != mVideoWidth && h != mVideoHeight) {this.mVideoWidth = w;this.mVideoHeight = h;int yarraySize = w * h;int uvarraySize = yarraySize / 4;synchronized (this) {y = ByteBuffer.allocate(yarraySize);u = ByteBuffer.allocate(uvarraySize);v = ByteBuffer.allocate(uvarraySize);}}}mParentAct.onPlayStart(); //请无视之Utils.LOGD("INIT X");}/*** this method will be called from native code, it's used for passing yuv data to me.*/public void update(byte[] ydata, byte[] udata, byte[] vdata) {synchronized (this) {y.clear();u.clear();v.clear();y.put(ydata, 0, ydata.length);u.put(udata, 0, udata.length);v.put(vdata, 0, vdata.length);}// request to rendermTargetSurface.requestRender();}}代码很简单，Renderer主要处理这么几个事：
1.Surface create的时候，我初始化了一些需要用到的Program/Shader，因为马上就要用到它们了；
2.Surface change的时候，重置一下画面；
3.onDrawFrame()时，把数据真正地“画”上去；
4.至于两个update方法，，是用来把图像的宽高/数据传过来的。
C 看GLProgram是怎么写的，它的作用是向Renderer提供计算单元，你所有对数据的处理，都在这儿了。
public boolean isProgramBuilt() {return isProgBuilt;}public void buildProgram() {createBuffers(_vertices, coordVertices);if (_program <= 0) {_program = createProgram(VERTEX_SHADER, FRAGMENT_SHADER);}Utils.LOGD("_program = " + _program);/** get handle for "vPosition" and "a_texCoord"*/_positionHandle = GLES20.glGetAttribLocation(_program, "vPosition");Utils.LOGD("_positionHandle = " + _positionHandle);checkGlError("glGetAttribLocation vPosition");if (_positionHandle == -1) {throw new RuntimeException("Could not get attribute location for vPosition");}_coordHandle = GLES20.glGetAttribLocation(_program, "a_texCoord");Utils.LOGD("_coordHandle = " + _coordHandle);checkGlError("glGetAttribLocation a_texCoord");if (_coordHandle == -1) {throw new RuntimeException("Could not get attribute location for a_texCoord");}/** get uniform location for y/u/v, we pass data through these uniforms*/_yhandle = GLES20.glGetUniformLocation(_program, "tex_y");Utils.LOGD("_yhandle = " + _yhandle);checkGlError("glGetUniformLocation tex_y");if (_yhandle == -1) {throw new RuntimeException("Could not get uniform location for tex_y");}_uhandle = GLES20.glGetUniformLocation(_program, "tex_u");Utils.LOGD("_uhandle = " + _uhandle);checkGlError("glGetUniformLocation tex_u");if (_uhandle == -1) {throw new RuntimeException("Could not get uniform location for tex_u");}_vhandle = GLES20.glGetUniformLocation(_program, "tex_v");Utils.LOGD("_vhandle = " + _vhandle);checkGlError("glGetUniformLocation tex_v");if (_vhandle == -1) {throw new RuntimeException("Could not get uniform location for tex_v");}isProgBuilt = true;}/*** build a set of textures, one for Y, one for U, and one for V.*/public void buildTextures(Buffer y, Buffer u, Buffer v, int width, int height) {boolean videoSizeChanged = (width != _video_width || height != _video_height);if (videoSizeChanged) {_video_width = width;_video_height = height;Utils.LOGD("buildTextures videoSizeChanged: w=" + _video_width + " h=" + _video_height);}// building texture for Y dataif (_ytid < 0 || videoSizeChanged) {if (_ytid >= 0) {Utils.LOGD("glDeleteTextures Y");GLES20.glDeleteTextures(1, new int[] { _ytid }, 0);checkGlError("glDeleteTextures");}// GLES20.glPixelStorei(GLES20.GL_UNPACK_ALIGNMENT, 1);int[] textures = new int[1];GLES20.glGenTextures(1, textures, 0);checkGlError("glGenTextures");_ytid = textures[0];Utils.LOGD("glGenTextures Y = " + _ytid);}GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _ytid);checkGlError("glBindTexture");GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_LUMINANCE, _video_width, _video_height, 0,GLES20.GL_LUMINANCE, GLES20.GL_UNSIGNED_BYTE, y);checkGlError("glTexImage2D");GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_LINEAR);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);// building texture for U dataif (_utid < 0 || videoSizeChanged) {if (_utid >= 0) {Utils.LOGD("glDeleteTextures U");GLES20.glDeleteTextures(1, new int[] { _utid }, 0);checkGlError("glDeleteTextures");}int[] textures = new int[1];GLES20.glGenTextures(1, textures, 0);checkGlError("glGenTextures");_utid = textures[0];Utils.LOGD("glGenTextures U = " + _utid);}GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _utid);GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_LUMINANCE, _video_width / 2, _video_height / 2, 0,GLES20.GL_LUMINANCE, GLES20.GL_UNSIGNED_BYTE, u);GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_LINEAR);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);// building texture for V dataif (_vtid < 0 || videoSizeChanged) {if (_vtid >= 0) {Utils.LOGD("glDeleteTextures V");GLES20.glDeleteTextures(1, new int[] { _vtid }, 0);checkGlError("glDeleteTextures");}int[] textures = new int[1];GLES20.glGenTextures(1, textures, 0);checkGlError("glGenTextures");_vtid = textures[0];Utils.LOGD("glGenTextures V = " + _vtid);}GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _vtid);GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, GLES20.GL_LUMINANCE, _video_width / 2, _video_height / 2, 0,GLES20.GL_LUMINANCE, GLES20.GL_UNSIGNED_BYTE, v);GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, GLES20.GL_NEAREST);GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, GLES20.GL_LINEAR);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);}/*** render the frame* the YUV data will be converted to RGB by shader.*/public void drawFrame() {GLES20.glUseProgram(_program);checkGlError("glUseProgram");GLES20.glVertexAttribPointer(_positionHandle, 2, GLES20.GL_FLOAT, false, 8, _vertice_buffer);checkGlError("glVertexAttribPointer mPositionHandle");GLES20.glEnableVertexAttribArray(_positionHandle);GLES20.glVertexAttribPointer(_coordHandle, 2, GLES20.GL_FLOAT, false, 8, _coord_buffer);checkGlError("glVertexAttribPointer maTextureHandle");GLES20.glEnableVertexAttribArray(_coordHandle);// bind texturesGLES20.glActiveTexture(_textureI);GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _ytid);GLES20.glUniform1i(_yhandle, _tIindex);GLES20.glActiveTexture(_textureII);GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _utid);GLES20.glUniform1i(_uhandle, _tIIindex);GLES20.glActiveTexture(_textureIII);GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, _vtid);GLES20.glUniform1i(_vhandle, _tIIIindex);GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);GLES20.glFinish();GLES20.glDisableVertexAttribArray(_positionHandle);GLES20.glDisableVertexAttribArray(_coordHandle);}/*** create program and load shaders, fragment shader is very important.*/public int createProgram(String vertexSource, String fragmentSource) {// create shadersint vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vertexSource);int pixelShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fragmentSource);// just checkUtils.LOGD("vertexShader = " + vertexShader);Utils.LOGD("pixelShader = " + pixelShader);int program = GLES20.glCreateProgram();if (program != 0) {GLES20.glAttachShader(program, vertexShader);checkGlError("glAttachShader");GLES20.glAttachShader(program, pixelShader);checkGlError("glAttachShader");GLES20.glLinkProgram(program);int[] linkStatus = new int[1];GLES20.glGetProgramiv(program, GLES20.GL_LINK_STATUS, linkStatus, 0);if (linkStatus[0] != GLES20.GL_TRUE) {Utils.LOGE("Could not link program: ", null);Utils.LOGE(GLES20.glGetProgramInfoLog(program), null);GLES20.glDeleteProgram(program);program = 0;}}return program;}/*** create shader with given source.*/private int loadShader(int shaderType, String source) {int shader = GLES20.glCreateShader(shaderType);if (shader != 0) {GLES20.glShaderSource(shader, source);GLES20.glCompileShader(shader);int[] compiled = new int[1];GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0);if (compiled[0] == 0) {Utils.LOGE("Could not compile shader " + shaderType + ":", null);Utils.LOGE(GLES20.glGetShaderInfoLog(shader), null);GLES20.glDeleteShader(shader);shader = 0;}}return shader;}/*** these two buffers are used for holding vertices, screen vertices and texture vertices.*/private void createBuffers(float[] vert, float[] coord) {_vertice_buffer = ByteBuffer.allocateDirect(vert.length * 4);_vertice_buffer.order(ByteOrder.nativeOrder());_vertice_buffer.asFloatBuffer().put(vert);_vertice_buffer.position(0);if (_coord_buffer == null) {_coord_buffer = ByteBuffer.allocateDirect(coord.length * 4);_coord_buffer.order(ByteOrder.nativeOrder());_coord_buffer.asFloatBuffer().put(coord);_coord_buffer.position(0);}}private void checkGlError(String op) {int error;while ((error = GLES20.glGetError()) != GLES20.GL_NO_ERROR) {Utils.LOGE("***** " + op + ": glError " + error, null);throw new RuntimeException(op + ": glError " + error);}}private static float[] squareVertices = { -1.0f, -1.0f, 1.0f, -1.0f, -1.0f, 1.0f, 1.0f, 1.0f, }; // fullscreenprivate static float[] coordVertices = { 0.0f, 1.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, 0.0f, };// whole-textureprivate static final String VERTEX_SHADER = "attribute vec4 vPosition;\n" + "attribute vec2 a_texCoord;\n"+ "varying vec2 tc;\n" + "void main() {\n" + "gl_Position = vPosition;\n" + "tc = a_texCoord;\n" + "}\n";private static final String FRAGMENT_SHADER = "precision mediump float;\n" + "uniform sampler2D tex_y;\n"+ "uniform sampler2D tex_u;\n" + "uniform sampler2D tex_v;\n" + "varying vec2 tc;\n" + "void main() {\n"+ "vec4 c = vec4((texture2D(tex_y, tc).r – 16./255.) * 1.164);\n"+ "vec4 U = vec4(texture2D(tex_u, tc).r – 128./255.);\n"+ "vec4 V = vec4(texture2D(tex_v, tc).r – 128./255.);\n" + "c += V * vec4(1.596, -0.813, 0, 0);\n"+ "c += U * vec4(0, -0.392, 2.017, 0);\n" + "c.a = 1.0;\n" + "gl_FragColor = c;\n" + "}\n";
这里面代码比较复杂，我在这里稍作解释：
从起点，到尽头，也许快乐，或有时孤独，
