How to find Frustum parametrs

I am doing Camera Calibration, and have lot’s of local cameras, and I need to render frustum, and it’s viewing angle for each. I know that i can do that with intrinsic and extrinsic parameters. BUT HOW??

If my understanding is right, i need to find : nearD, farD, ratio, angle. But again, how??

p.s. I have intrinsic and extrinsic parameters, for each local camera.


i am not shure what you exactly need,
but if you have a camara you should have a perspective matrix as well, and you are able ro get this one from open gl:

GLdouble projMatrix[16];
GLdouble modelMatrix[16];
glGetDoublev(GL_PROJECTION, projMatrix);
glGetDoublev(GL_MODELVIEW, modelMatrix);

so if you have the matrix for every camera you should have everithing you need.


Thanks, but that is not what I need, cause I don’t know PRM, MDV for my lo