AcceuilHome ReProjector free application to demonstrate different projections

ReProjector, ©Marc Chauvière, is a free application written for Windows 32bit O/S to demonstrate how an equirectangular image (spherical) of a partial panorama can be rendered by different projections to make pictures to be seen entirely on screen or to be printed. Pictures can't be used with a panorama viewer in Internet pages.

ReProjector is not another warping or squeezing software starting from rectilinear picture : it needs an equirectangular panorama and you must inform it about panorama extend angles.
ReProjector is compiled with PBWin 9.0 ( and used an image helper: GFL-SDK ©Pierre Gougelet (, thanks to Pierre to make his libGFL free for non-commercial use. Application is working fine under Windows 32bit : XP Pro or Vista/Aero. As it's a graphical/picture software, it may not run under O/S emulator like "Parallels" / MAC or "Wine" / Linux, not my fault Hmm!

What do you need?

+ ReProjector application, see download section below
+ panorama picture in equirectangular (spherical) projection: only JPEG format is supported in this first version. As this is a demo, it's recommended to make a copy downsized to width in [1200, 2400] and height in [800, 1600] pixels
+ horizontal (theta) and vertical (phi) extend (Field of View) of the panorama as minimum and maximum values because projecting is relative to the panorama centre. ReProjector is able to read project.pano file recorded by AutoPano Pro stitcher (

How looks ReProjector screens?

First screen is used to load equirectangular picture, to define panorama extend and the cropping rectangle: maximum field of view is -89.5°/+89.5° horizontal, -81.0°/+81.0° vertical for cropped area.
Panorama extend, cropping
Second screen use the equirectangular picture cropped to your needs with a layout of lines to show the area that will be kept in the projected picture. Smaller trapezoids indicate higher stretching in result picture. Cropping controls disappear from the left, projection choice and parameters can be used now on the right.
Cropped equirect, layout for projection
Third and last screen is a preview of reprojected picture according to projection choice in the list and parameters that you can modify to obtain the best, maybe not yet your dream. Export button will write reprojected picture as JPEG with some text tagged to remember projection parameters. It's a demonstration application Cool!
Preview, export

Downloads and installation

- ReProjector application, v1-04, with 2 JPEG examples: ReProjectorPack-v1-04.ZIP (2270 KB)
changed in v1-04:
+ 'Mercator' have a parameter to modify the vertical expansion (1.0=Mercator, 1.25=Miller-1, 1.5=Miller-2)
+ added 'Equirect Pannini' projection with a paramater to compress the vertical expansion (similar to 'Recti-perpective' projection in PTAssembler)

- ReProjector manual, v1-01: ReProjector-Manual-1-0.PDF (3599 KB)

No installation helper is included, just create a subfolder on your hard-disk then uncompress the ZIP archive inside it and place de PDF manual inside too. You can easily add a shortcut to "ReProjectorWin.exe" on your desktop.

ReProjector isn't writing any files in system folder, isn't creating any subkeys in the registry. To uninstall, you can safely delete files and the subfolder where you uncompressed ReprojectorPack before. You should also delete job.reprj files that you recorded maybe in your image folder tree.

No specific forum or blog exist for ReProjector, you can add comments or suggestions to the post in forum where you found ReProjector.

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