stereo image proc bypass

Ubuntu 14.04 ROS Indigo Igloo Bumblebee2 Hello! I am using a lookup table to rectify the images extracted with [camera1394stereo](http://wiki.ros.org/camera1394stereo) generated outside ROS with triclops. Now I have the "perfect" rectification but I want to bypass the stereo image proc to avoid the process of rectification, normalization and rotation. I just want to generate the disparity image and the PointCloud2 image to use it in [viso2_ros](http://wiki.ros.org/viso2_ros). The problem is that I don't have the correct parameters to fill the camera_info msg left and right cameras. As long I understand, viso2_ros use image_proc to do all the process to generate rectified images. Is there some way to use image_proc, stereo_image_proc or depth_image_proc to get the disparity image and the pointCloud without do the rectification? Thanks in advance.