我正在使用ffmpeg在Android上使用rtsp播放器来连接和解码视频流。我想使用OpenGL es 2.0将YUV框架转换为RGB框架并显示，但我被阻止(这是我第一次使用opengl)。
我会尽量解释我的问题。
从NDK android我初始化一个opengl上下文(从线程我想用来显示图像)使用这种方法：
//
EGLint attribs[] = {
EGL_SURFACE_TYPE,EGL_WINDOW_BIT,EGL_RENDERABLE_TYPE,EGL_OPENGL_ES2_BIT,EGL_BLUE_SIZE,8,EGL_GREEN_SIZE,EGL_RED_SIZE,EGL_ALPHA_SIZE,EGL_NONE
};
EGLint contextAttrs[] = {
EGL_CONTEXT_CLIENT_VERSION,2,EGL_NONE
};
LOGI("Initializing context");
if((display = eglGetDisplay(EGL_DEFAULT_DISPLAY)) == EGL_NO_DISPLAY)
{
closeContext();
return;
}
if(!eglInitialize(display,0))
{
closeContext();
return;
}
if(!eglChooseConfig(display,attribs,&config,1,&numConfigs))
{
closeContext();
return;
}
if(!eglGetConfigAttrib(display,config,EGL_NATIVE_VISUAL_ID,&format))
{
closeContext();
return;
}
ANativeWindow_setBuffersGeometry(window,format);
if(!(surface = eglCreateWindowSurface(display,window,0)))
{
closeContext();
return;
}
if(!(context = eglCreateContext(display,contextAttrs)))
{
closeContext();
return;
}
if(!eglMakeCurrent(display,surface,context))
{
closeContext();
return;
}
if(!eglQuerySurface(display,EGL_WIDTH,&width) || !eglQuerySurface(display,EGL_HEIGHT,&height))
{
closeContext();
return;
}
LOGI("EGLWIDTH : %d EGLHEIGHT : %d ",(int)width,(int)height);
isInitEGLContext = 1;
然后我使用这种方法设置图形：
//
//Load Vertex and Fragment Shader,attach shader and link program
programId = createProgram(kVertexShader,kFragmentShader);
LOGI("Program id : %d error : %d",(int) programId,glGetError());
if(!programId)
{
LOGI("Could not create program");
return;
}
// get index of the generic vertex attribute bound to vPosition
positionObject = (int) glGetAttribLocation(programId,"vPosition");
// get index of the generic vertex attribute bound to vTexCoord
texturePosition = (int) glGetAttribLocation(programId,"vTexCoord");
// get the location of yTexture within the program (corresponding to program id)
yuv_texture_object[0] = glGetUniformLocation(programId,"yTexture");
// get the location of uTexture within the program
yuv_texture_object[1] = glGetUniformLocation(programId,"uTexture");
// get the location of vTexture within the program
yuv_texture_object[2] = glGetUniformLocation(programId,"vTexture");
// Setup width of each planes (display size)
stream_yuv_width[0] = 800;
stream_yuv_width[1] = 400;
stream_yuv_width[2] = 400;
// Setup height of each planes (display size)
stream_yuv_height[0] = 600;
stream_yuv_height[1] = 300;
stream_yuv_height[2] = 300;
//set the view port
glViewport(0,stream_yuv_width[0],stream_yuv_height[0]);
LOGI("glViewPort() %d ",glGetError());
我已经硬编码显示大小(现在)，直到我得到一些工作。
createProgram方法，加载着色器，创建程序，编译和链接着色器成功。
这是我的着色器：
const char kVertexShader[] =
"attribute vec4 vPosition;\n"
"attribute vec2 vTexCoord;\n"
"varying vec2 v_vTexCoord;\n"
"void main() {\n"
"gl_Position = vPosition;\n"
"v_vTexCoord = vTexCoord;\n"
"}\n";
const char kFragmentShader[] =
"precision mediump float; \n"
"varying vec2 v_vTexCoord;\n"
"uniform sampler2D yTexture;\n"
"uniform sampler2D uTexture;\n"
"uniform sampler2D vTexture;\n"
"void main() {\n"
"float nx,ny; \n"
"nx = v_vTexCoord.x; \n"
"ny = v_vTexCoord.y; \n"
"float y=texture2D(yTexture,v_vTexCoord).r;\n"
"float u=texture2D(uTexture,vec2(nx / 2.0,ny / 2.0)).r;\n"
"float v=texture2D(vTexture,ny / 2.0)).r;\n"
"y = 1.1643 * (y - 0.0625);\n"
"u = u - 0.5; \n"
"v = v - 0.5; \n"
"float r=y + 1.5958 * v;\n"
"float g=y - 0.39173 * u - 0.81290 * v;\n"
"float b=y + 2.017 * u;\n"
"gl_FragColor = vec4(r,g,b,1.0);\n"
"}\n";
const GLfloat kVertexInformation[] = {
-1.0f,1.0f,// TexCoord 0 top left
-1.0f,-1.0f,// TexCoord 1 bottom left
1.0f,// TexCoord 2 bottom right
1.0f,1.0f // TexCoord 3 top right
};
const GLshort kTextureCoordinateInformation[] = {
0,// TexCoord 0 top left
0,// TexCoord 1 bottom left
1,// TexCoord 2 bottom right
1,0 // TexCoord 3 top right
};
const GLuint kStride = 0;//COORDS_PER_VERTEX * 4;
const GLshort kIndicesInformation[] = {
0,3
};
然后我设置yuv纹理和渲染到纹理，此时yuv_width [i]和yuv_height [i]设置为正确的值：
void setupYUVTexture()
{
//Setup the pixel alignement
glPixelStorei(GL_UNPACK_ALIGNMENT,1);
LOGI("glPixelStorei() : %d ",glGetError());
int i = 0;
for(i = 0 ; i < 3 ; ++i)
{
//Check if the texture already setup
if(yuv_texture_id[i] != 0)
{
glDeleteTextures(1,&yuv_texture_id[i]);
yuv_texture_id[i] = 0;
}
// Active the i texture
glActiveTexture(GL_TEXTURE0 + i);
//Generate the texture name
glGenTextures(1,&yuv_texture_id[i]);
// Bind the texture
glBindTexture(GL_TEXTURE_2D,yuv_texture_id[i]);
// Setup the texture parameters
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_NEAREST);
glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_CLAMP_TO_EDGE);
glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_CLAMP_TO_EDGE);
//Define the texture image
glTexImage2D(GL_TEXTURE_2D,GL_LUMINANCE,yuv_width[i],yuv_height[i],GL_UNSIGNED_BYTE,NULL);
LOGI("glTexImage2D() %d ",glGetError());
}
}
void renderToTexture()
{
// Generate framebuffer object name
glGenFramebuffers(1,&frameBufferObject);
//Bind the framebuffer
glBindFramebuffer(GL_FRAMEBUFFER,frameBufferObject);
//Generate render buffer object name
glGenRenderbuffers(1,&renderBufferObject);
//Bind render buffer
glBindRenderbuffer(GL_RENDERBUFFER,renderBufferObject);
//Create and initialize render buffer for display RGBA with the same size of the viewport
glRenderbufferStorage(GL_RENDERBUFFER,GL_RGBA4,800,600);
//Attach render buffer to frame buffer object
glFramebufferRenderbuffer(GL_FRAMEBUFFER,GL_COLOR_ATTACHMENT0,GL_RENDERBUFFER,renderBufferObject);
//Attach y plane to frame buffer object
glFramebufferTexture2D(GL_FRAMEBUFFER,GL_TEXTURE_2D,yuv_texture_id[0],0);
//Attach u plane to frame buffer object
glFramebufferTexture2D(GL_FRAMEBUFFER,yuv_texture_id[1],0);
//Attach v plane to frame buffer object
glFramebufferTexture2D(GL_FRAMEBUFFER,yuv_texture_id[2],0);
// Bind the framebuffer
glBindFramebuffer(GL_FRAMEBUFFER,0);
//Check if the framebuffer is correctly setup
GLint status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
if(status != GL_FRAMEBUFFER_COMPLETE)
{
LOGI(" FBO setting fault : %d ",status);
return;
}
}
要完成，我的画框方法：
void drawFrame()
{
LOGI("DrawFrame");
glBindFramebuffer(GL_FRAMEBUFFER,frameBufferObject);
printGLError("glBindFramebuffer");
glUseProgram(programId);
printGLError("glUseProgram");
int i = 0;
for(i = 0 ; i < 3 ; ++i)
{
glActiveTexture(GL_TEXTURE0 + i);
printGLError("glActiveTexture");
glBindTexture(GL_TEXTURE_2D,yuv_texture_object[i]);
printGLError("glBindTexture");
glUniform1i(yuv_texture_object[i],i);
printGLError("glUniform1i");
LOGI("Plan : %d Largeur : %d Hauteur : %d ",i,yuv_height[i]);
glTexSubImage2D(GL_TEXTURE_2D,yuv_planes[i]);
printGLError("glTexSubImage2D");
}
glVertexAttribPointer(positionObject,GL_FLOAT,GL_FALSE,kStride,kVertexInformation);
printGLError("glVertexAttribPointer");
glVertexAttribPointer(texturePosition,GL_SHORT,kTextureCoordinateInformation);
printGLError("glVertexAttribPointer");
glEnableVertexAttribArray(positionObject);
printGLError("glVertexAttribArray");
glEnableVertexAttribArray(texturePosition);
printGLError("glVertexAttribArray");
glBindFramebuffer(GL_FRAMEBUFFER,0);
printGLError("glBindFramebuffer");
glDrawElements(GL_TRIANGLE_STRIP,6,GL_UNSIGNED_SHORT,kIndicesInformation);
printGLError("glDrawElements");
eglSwapBuffers(display,surface);
printGLError("eglSwapBuffers");
}
一旦opengl纹理和其他必需的属性初始化，那么当一个帧被解码时，我将y缓冲区重新映射到yuv_planes [0]中的u缓冲区，yuv_planes [1]中的u缓冲区以及yuv_planes [2]中的v缓冲区。
一旦使用ffmpeg i正确地解码帧，我按以下顺序调用：
initContext()
– setupGraphics()
– setupYUVTexture()
– renderToTexture()
然后我调用drawFrame。当然，当一切都被初始化时，我在每个解码帧之后直接调用drawFrame。
有我现在的输出。
图像的大小是正确的，但现在我在这里阻止。我不明白为什么图像显示是绿色的！
有任何想法吗
