Android OpenGL es GPUImage convert YUV to RGB

Android OpenGL-ES GPUImage

1，YUV转RGB

andorid 的camera数据是YUV数据，需要转换成rgb，但是普通的转换效率不高，即使使用jni转换也依然如此

修改fragment shader脚本如下：

    varying highp vec2 textureCoordinate;
    uniform sampler2D inputImageTexture;
    uniform sampler2D uvTexture;
    precision mediump float;
    void main(){
         vec4 y = vec4((texture2D(inputImageTexture, textureCoordinate).r - 16./255.) * 1.164);  
         vec4 u = vec4(texture2D(uvTexture, textureCoordinate).a - 128./255.);  
        vec4 v = vec4(texture2D(uvTexture, textureCoordinate).r - 128./255.);  
        y += v * vec4(1.596, -0.813, 0, 0);
        y += u * vec4(0, -0.392, 2.017, 0); 
        y.a = 1.0;
        gl_FragColor = y;//texture2D(inputImageTexture, textureCoordinate);
               }

这是是关键代码 YUV数据转换成RGBA

2，坐标转换

坐标转换 例如平移缩放旋转等
坐标脚本

    VERTEX_SHADER = "uniform mat4 uMVPMatrix;\n"
                + "attribute vec4 position;\n" + "attribute vec4 inputTextureCoordinate;\n" + " \n"
                + "varying vec2 textureCoordinate;\n" + " \n" + "void main()\n" + "{\n"
                + "    gl_Position = uMVPMatrix * position; \n"
                + "    textureCoordinate = inputTextureCoordinate.xy;\n" + "}";

多添加了uMVPMatrix

Matrix.frustumM(mProjMatrix, 0, -ratio, ratio, -1, 1, 1, 2);

    Matrix.setLookAtM(mVMatrix, 0,//
            0, 0, cameraId == Camera.CameraInfo.CAMERA_FACING_FRONT ? -1 : 1, //eye
            0f, 0f, 0f,//center
            0f, 1f, 0f//up
    );
    //eye 坐标的eyez 正值时候看到的景物是折叠的

    float y = ((maxHeight - height) / 1f / maxHeight);
    Matrix.translateM(mVMatrix, 0,//
            0, y, 0f//x,y,z
    );

    Matrix.rotateM(mVMatrix, 0, mRotation.asInt(), 0, 0, -1);