Abstract:
Panoramic Images are wide angle view and wide aspect ratio images. Wide aspect ratio images
mean the images with width greater than that of their height. These Panoramic images are
formed using a stitching process in which multiple photographic images with overlapping field
of view are aligned and combine together in a seamless manner. These high resolution images
are widely used in medical and biological fields for clinical studies, Because of their high
resolution and wide angle view panoramic images are very suitable for surveillance and military
application.
For joining these images first we have to align them and for aligning images to same frame of
reference different mathematical models are used to map pixel coordinates from one image to
another, parameters for these transformations are estimated through different techniques
generally categorized as direct pixel base methods and feature base methods. In direct pixel base
methods pixel to pixel base dissimilarities are minimized using error matrices and these
techniques include difference base methods and correlation methods while on the other hand in
feature base methods prominent features of images are detected matched and optimization
techniques are used to estimate the parameters of transformation. We have designed an algorithm
that will used physical camera orientation in azimuth and elevation to estimate the parameters of
translational transformation to align and stitch the images together. We have used encoders for
position estimation in azimuth and elevation these encoders have 20000 encoder counts per 360
degree which are then change in to pixels using scales that are found after camera calibration,
these camera positions are sampled every 20ms. This technique is implemented for Real time
Panoramic scanning Surveillance application on FPGA Spartan 6. For achieving real time
performance an advance memory management scheme is designed and implemented on in built
128 MB ddr2 memory. The camera used is a dual field of view long range thermal camera
capturing 50 frames per second with a resolution of 320 x 256. There are two surveillance modes
sector scan mode and 360 degree scanning mode and to display it on a HDMI LCD with limited
resolution of 1024 x 768 a display scheme is designed.
