主要相关函数是这三个，根据 http://blog.csdn.net/leixiaohua1020/article/details/40379845 这篇文章和Qt自带的例子想结合改动
initializeGL{
initializeOpenGLFunctions();
glEnable(GL_DEPTH_TEST);
glEnable(GL_TEXTURE_2D);
initshader();
}
initshader{
QOpenGLShader *vshader = new QOpenGLShader(QOpenGLShader::Vertex, this);
const char *vsrc =
"attribute vec4 vertexIn;\n"
"attribute vec2 textureIn;\n"
"varying vec2 textureOut;\n"
"void main(void)\n"
"{\n"
" gl_Position = vertexIn;\n"
" textureOut = textureIn;\n"
"}\n";
vshader->compileSourceCode(vsrc);
QOpenGLShader *fshader = new QOpenGLShader(QOpenGLShader::Fragment, this);
const char *fsrc =
"precision highp float;"
"varying vec2 textureOut;\n"
"uniform sampler2D tex_y;\n"
"uniform sampler2D tex_u;\n"
"uniform sampler2D tex_v;\n"
"void main(void)\n"
"{\n"
" vec3 yuv;\n"
" vec3 rgb;\n"
" yuv.x = texture2D(tex_y, textureOut).r;\n"
" yuv.y = texture2D(tex_u, textureOut).r - 0.5;\n"
" yuv.z = texture2D(tex_v, textureOut).r - 0.5;\n"
" rgb = mat3( 1, 1, 1,\n"
" 0, -0.39465, 2.03211,\n"
" 1.13983, -0.58060, 0) * yuv;\n"
" gl_FragColor = vec4(rgb, 1);\n"
"}\n";
fshader->compileSourceCode(fsrc);
program = new QOpenGLShaderProgram;
program->addShader(vshader);
program->addShader(fshader);
program->bindAttributeLocation("vertexIn", PROGRAM_VERTEX_ATTRIBUTE);
program->bindAttributeLocation("textureIn", PROGRAM_TEXCOORD_ATTRIBUTE);
program->link();
program->bind();
program->setUniformValue("textureOut", 0);
program->setAttributeValue("VShowBackColor", 1.0);
textureUniformY = program->uniformLocation("tex_y");
textureUniformU = program->uniformLocation("tex_u");
textureUniformV = program->uniformLocation("tex_v");
glVertexAttribPointer(PROGRAM_VERTEX_ATTRIBUTE, 2, GL_FLOAT, 0, 0, vertexVertices);
glEnableVertexAttribArray(PROGRAM_VERTEX_ATTRIBUTE);
glVertexAttribPointer(PROGRAM_TEXCOORD_ATTRIBUTE, 2, GL_FLOAT, 0, 0, textureVertices);
glEnableVertexAttribArray(PROGRAM_TEXCOORD_ATTRIBUTE);
glGenTextures(1, &id_y);
glBindTexture(GL_TEXTURE_2D, id_y);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glGenTextures(1, &id_u);
glBindTexture(GL_TEXTURE_2D, id_u);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glGenTextures(1, &id_v);
glBindTexture(GL_TEXTURE_2D, id_v);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
}
paintGL{
glClearColor(0.0,0.0,0.0,0.0);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D, id_y);
glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, fYSize, fHeight, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, fY);
glUniform1i(textureUniformY, 0);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, id_u);
glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, fYSize/2, fHeight/2, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, fU);
glUniform1i(textureUniformU, 1);
glActiveTexture(GL_TEXTURE2);
glBindTexture(GL_TEXTURE_2D, id_v);
glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, fYSize/2, fHeight/2, 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, fV);
glUniform1i(textureUniformV, 2);
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
}
