Remapping

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It highly depends on [[aligning]], since any alignment change of an image requires a different remapping. Remapping is an inherent part of the [[stitching]] process.
 
It highly depends on [[aligning]], since any alignment change of an image requires a different remapping. Remapping is an inherent part of the [[stitching]] process.
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Although the software remaps in one single step, one can conceptually identify several logical steps.
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=== Camera image to sphere ===
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The camera image has to be transformed into angle space, which here is visualised as projecting the image from a virtual camera, reversing the light path, onto a sphere.
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[[Image:Img08232.jpg|300px]] [[Image:Globe05png.svg|230px]]
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=== Relative alignment ===
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Generally, one is free to choose any orientation of the virtual camera/projector. But for panoramic images, one wants to align these images. The usual software approach is to mark a set of same features in image pairs, and have the distance between such marker pairs minimised in an overall optimisation process.
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[[Image:Img0823xcp3.png|672px]]
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=== Screen projection ===
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Images in the computer environment are flat, hence one has to remap the spherical geometry. This can be a general mathematical mapping function. Some mappings, as the rectilinear projection below, can be visualised as an optical projection, using a point light source in the centre of the sphere.
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[[Image:Globe08png.svg|240px]][[Image:Img0823xstitch6.jpg|400px]]

Latest revision as of 14:13, 5 May 2008

Contents

[edit] Definition

Remapping is the process of changing the image geometry in order to fit to the adjacent images that should contribute to a panorama.

It highly depends on aligning, since any alignment change of an image requires a different remapping. Remapping is an inherent part of the stitching process.

Although the software remaps in one single step, one can conceptually identify several logical steps.

[edit] Camera image to sphere

The camera image has to be transformed into angle space, which here is visualised as projecting the image from a virtual camera, reversing the light path, onto a sphere.

Img08232.jpg Globe05png.svg

[edit] Relative alignment

Generally, one is free to choose any orientation of the virtual camera/projector. But for panoramic images, one wants to align these images. The usual software approach is to mark a set of same features in image pairs, and have the distance between such marker pairs minimised in an overall optimisation process.

Img0823xcp3.png

[edit] Screen projection

Images in the computer environment are flat, hence one has to remap the spherical geometry. This can be a general mathematical mapping function. Some mappings, as the rectilinear projection below, can be visualised as an optical projection, using a point light source in the centre of the sphere.

Globe08png.svgImg0823xstitch6.jpg

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