Work-flow steps for creating Panoramic 3D PDF Brochures
The steps in this work-flow are an outline of how to create a highly compelling 3D panoramic scene embedded inside a PDF brochure or report. The steps start with digital photography and end with the production of a secure, stand-alone PDF file.
There are a number of high quality production interactive photographic panorama methods today where the final delivery is over the web. These include using Flash as an embedded custom image viewer, or using interactive and streaming HTML5 with JavaScript in a browser. Each of these are strongly network-connected technologies, where view point and level of detail information to update the user’s view are flowing across the network.
However, in some applications, live network connections may not be available or not permitted. As PDF is such an extremely well established off-line document format, with Adobe Reader available on most PCs, embedding a 3D panoramic scene in a PDF brochure opens up a distinct deployment option.
Panoramic Photography
To avoid parallax problems, a special panoramic head assembly is used to have the optical centre of the used lens exactly in the centre of the panorama. The photography is done in predefined segments, using technologies like focus stacking in confined space, or to achieve the best possible quality. To cover the full dynamic range of a scene, photos of each segment with different exposures may be necessary, resulting in a large number of high resolution images to process.
Alternatively, there is currently a fresh crop of direct Panoramic Cameras, from Ricoh, Samsung, Kodak, etc. These directly generate a fully stitched pano JPEG, allowing users to skip the image processing and other software processing steps.
Image Processing
After offloading the images to a digital image processing computer workstation, the photos of each individual segment are combined to achieve unlimited depth of field, and to cover the full dynamic range of the original scene. The processed segments are then stitched together to create a huge, flat image that is edited for light & colour temperature conformance, and to correct possible geometric distortions. The resulting image can be huge – 2.5 Gigabytes in the Sheldonian Theatre example. For the web, this huge image is then processed into a spherical view for publishing in HTML5 or, as a fall-back, Flash.
Preparing Photo
To prepare for 3D PDF Brochure production, the resolution should be resampled down to a modest 8000 by 4000 pixel size. An additional constraint is that the Aspect Ratio ratio should be as close to 2:1 as practical, in landscape layout. The recommended File Format for this method is JPEG in full 24-bit colour depth.
Spherical Geometry
Independently, a Spherical Texture Map Framework is used, whereby a triangulated sphere object is defined. This is a tessellated sphere with shared vertices and texture UV mapping coordinates specified per vertex. The texture mapping is defined such that an image wrapped into a cylinder is projected onto the sphere.
With an image as diffuse material channel with ambient and specular terms set very low. The sphere geometry can be defined in many modelling packages, in this case a VRML97 implicit sphere is specified which can be re-used on all similar projects without further editing.
MS-Word Brochure Design
Next the brochure layout, text, images, web links can be prepared using normal desk-top publishing tools. In this work-flow Microsoft WORD is used to make a one-page landscape brochure page, where logo, website references and a description of the 3D scene content is included to provide context to the viewer.
Once the basic brochure design is complete, the “PDF3D with WORD” plugin is used to add an area on the brochure where the 3D panoramic scene will be placed. This creates a special template placeholder image, which is then exported as a placeholder PDF using the plugin ribbon menu buttons.
PDF3D ReportGen Operations
The actual conversion and introduction of the interactive 3D scene is performed by using the PDF3D ReportGen application software. Once this is started, a new project is established with the following menu adjustments made.
First, import Panoramic_Profile.pdf3dsettings.
Next, set output PDF brochure file name to the final name to use during export.
Finally Click Convert.
Advanced Adjustments
All of the above settings can easily be made using the PDF3D ReportGen menu entries. Further adjustments to tilt angle, spin rotation and field of view limits are set using the PDF 3D Settings sub-menu. Under the Geospatial Image menus, the actual image processing steps of tiling, subsample division and texture treatment is specified.
Final Conversion and 3D PDF Generation
Convert, and the new PDF should now be written out to a stand-alone file, and opened for review.
The PDF file size will be proportional to the JPEG re-sampled panoramic image file size.
References
- PDF3D Tools http://www.pdf3d.com
- Sheldonian Theater http://www.admin.ox.ac.uk/sheldonian/
- Harald Joergens Photography https://www.haraldjoergens.com/
- Panoramic Photography https://en.wikipedia.org/wiki/Panoramic_photography
- XML Extensible Markup Language W3C Reference http://www.w3.org/XML/
- Photography Industry Page Overview
- Panoramic 360 Image to PDF Feature Overview