Warp and Blend are interfaces exposed in NVAPI for warping (image geometry corrections) and blending (intensity and black level adjustment) a single display output or multiple display outputs
Many display applications benefit from combining multiple projectors or displays into one larger display surface. If all the displays are aligned in a grid with no overlap, features like Mosaic make it easy to create a single unified display from multiple physical displays. When the displays are rotated at odd angles or the display surface is an irregular shape, multiple projectors need to overlap, blend together and be mapped or adjusted to the display surface. The Warp and Blend SDK provides an easy way to bring this functionality to any application with minimal performance impact and no incremental latency.
Twist gives you software options for warping and blending on all Christie 3DLP projectors and most Christie HS Series 1DLP laser projectors, allowing pixels to be mapped more easily onto any projection surface, maintaining proper geometry and accurate pixel-to-pixel alignm ent. The technology also provides networked projector control by allowing you to launch a virtual remote from within the Twist software. My Personal DIY Curved Screen - Part 1. First I have to correct something from the previous post, in this picture: “Length of overlap” is not correct since the projector will have a bit of keystoning. You do not want to use any keystone correction. Keystone adds latency since the picture has to be processed by the projector. Curved Projection Screen. We make curved screens, screens for active and passive 3D simulator screens and simulation displays. C urved Projection S creen is a customized product that is made-to-order for each customer. For the curved screen, a unique material is applied to the frame that is specially manufactured to ensure that the screen has. Pixelwix Software. Pixelwix specialize in software solutions for Geometric Correction (warping for curved screens), Edge-blending and video switching / presentation solultions. Pixelwarp Warp and blend software allows multiple projectors to be blended and displayed as one large mega pixel screen. The easy warp correction tool removes the distortions from projecting on a curved surface.
In the example above both warp and blend are used to achieve a seamless, blended picture from two projectors illuminating a curved screen. A standard practice when using multiple projectors is to overlap the seams where each projected image touches another. Since optics and screens are never perfect and overlapping can create hotspots (regions gets twice amount of light) blend is used to adjust the intensity of the overlapping region. Warp is used to modify geometry so that it matches the curve of the projection wall.
Traditionally, warp and blend operations are done with custom hardware using features built into the projector or with direct modifications to an application. The Warp and Blend SDK provides an easy way to bring this functionality to any application with minimal performance impact and no incremental latency.
Warp and Blend is part of NVAPI
NVAPI is NVIDIA's core software development kit that allows direct access to NVIDIA GPUs on windows platforms. Warp and blend is implemented as an interface in NVAPI that programmably exposes warping and intensity adjustment features before the final scanout. Working in conjunction with a supported NVIDIA Display Driver, the warp and blend features works on a single screen, multiple screens and multi-gpu configurations and are available only with NVIDIA Quadro GPUs.
Learn more about NVAPI.
Download Warp and Blend Sample
Download the Warp and Blend programming sample package to get started developing with warp and blend and NVAPI. To download, you must be a member of NVIDIA Developer - DesignWorks.
By clicking the 'Agree & Download' button below, you are confirming that you have read and agree to be bound by the SOFTWARE DEVELOPER KITS, SAMPLES AND TOOLS LICENSE AGREEMENT for use of the SDK package. The download will begin immediately after clicking on the 'Agree & Download' button below.
Join the NVIDIA Developer Program
Get access to the latest software releases and tools and receive notifications and invites to join special developer events, early access programs and educational webinars. The program is free-to-join and open to all developers.
Key Features
- Generate a seamless image on up to 16 displays or projectors with warp and blend using NVIDIA Mosaic Technologies and NVIDIA Quadro Sync (ability to synchronize up to four Quadro GPUs per system).
- Apply warping to any scenario that requires image geometry corrections such as rotation, skew, mirroring, offset, and geometry mapping.
- Adjust intensity and black level in portions of a screen, every pixel if desired.
- Minimal performance impact and no incremental latency.
- Works in single screen, multiple screens and multi-gpu configurations.
| Operating System | Windows 7, 8, 10, Server 2008R2, Server 2012 |
|---|---|
| Dependencies | NVIDIA Quadro 1200 class or higher products with Fermi, Kepler, Maxwell or newer GPUs NVS 810 & 510 Windows Quadro Display drivers 302.82 or newer |
Why do Warp and Blend on the GPU?
Traditionally, warp and blend is integrated into the projector or done using custom hardware appliances which adds performance delay to the display pipeline. It can also be done using software applications but that may not conform to all use cases. Since the pixel information is already available to the GPU, the GPU is the natural place to do this work. GPUs also bring additional benefits to warp and blend:
- GPUs are inherently parallel for fast image processing operations
- Ability to perform transformation in the display pipeline before the pixel get scanned out
- Minimal performance delay to display pipeline compared to external boxes using FPGAs
- Cost effective and easily scalable
Warp and Blend In Action
Immersive VR using a domed screen
The Operational Based vision Assessment (OBVA) Simulator at NASA.
Image courtesy of NASA
Projection mapping onto scale physical models
A 1:5 scale, blank canvas model car with car’s features projected onto the surface of the model to replicate a photo-real, physical object for real-time interaction and customization.
Image courtesy of Christie Digital
Simulator environment with large curved front displays
The PanoLab is a wide-area high realistic projection system for interactive presentations of virtual environments. The half-spherical screen of PanoLab allows the simulation of large visual fields providing an increased degree of immersion. The PanoLab was calibrated using nWarp, part of the ProjectionTools automatic calibration system from domeprojections.com
Image courtesy of Joachim Tesch. Max Planck Institute for Biological Cybernetics.
Multi-projection display walls
Using a matrix of projections projected to a single screen to present a seamless large scale, single image.
Developer Forums
Our forum community is where Developers can ask questions, share experiences and participate in discussions with NVIDIA and other experts in the field.
Check out the forums here.
Resources
Warp and Blend Presentations
Update on Warping Standards
Video
Video Presentation
Video Presentation
Video Presentation
Additional Resources
- NVAPI Software Development Kit (Windows only)
- NVAPI Documentation (PDF)
What is throw distance for a projector?
A projector's distance from the lens to the screen surface is called the Throw Distance. The throw distance and the size of the image it produces on the screen are proportional to each other based on the optics of the lens. As you increase the distance between the projector lens and the screen the image will also increase.
How far do you put a projector from the screen?
Projection Calculator Software For Curved Screens Windows
A projector's distance from a screen and the size of the image it produces are proportional to each other based on the optics of the lens. As you increase the distance between the projector and a screen the image will also increase. If your projector has a zoom lens, the lens can be adjusted to change the size of the screen image without changing the distance of the projector. Since each projector lens is different, an online projection calculator tool will help you calculate the size of an image on a screen relative to how far the projector is placed from screen.
What is a throw ratio for a projector?
Projection Calculator Software For Curved Screens Free
For any given projector, the width of the image (W) relative to the throw distance (D) is know as the throw ratio D/W or distance over width. So for example, the most common projector throw ratio is 2.0. This means that for each foot of image width, the projector needs to be 2 feet away or D/W = 2/1 = 2.0. So if I'm using a projector with a throw ratio of 2.0 and I have an image width of 5 feet, then my throw distance must be 10 feet. So the throw ratio is a simple formula that let's you easily compute throw distance or image width given that you know one of these measurements. A projector zoom lens will have two different throw ratios, one for the minimum zoom setting and one for the maximum zoom setting.
What is considered a short throw projector?
A short throw projector is a projector with a lens that has a throw ratio of 0.4 (distance/width) or less. These projectors are ideal for rear screen applications where the area behind the screen is limited, or for a wall mounted application where the projector will be mounted within 1 or 2 feet from the screen. The goal of these projectors is to produce as large of an image within the shortest amount of space between the projector and the screen.