Spherical Video PTZ: User Guide - Quick Start Guide

Spherical Video PTZ
Getting Started
Spherical Video PTZ Projections Used Evaluating the Product Getting the code
User Guide
Building and Installation Quick Start Guide
Examples
Gst-launch GstD
Performance
Jetson AGX Xavier
Contact Us

Libpanorama

This wiki introduces a basic use of Spherical Video PTZ for converting equirectangular images to rectilinear format with an engine. It includes a simple example and instructions on how to use the engine for different needs. The engine makes it easy to change panoramic images into a straight view, useful for many projects.

Minimal Application

After Building and Installation, follow these steps:

1. Download the sample images, if you haven't already.

cd $SAMPLES
./download_samples.sh

2. This example demonstrates the use of the Spherical Video PTZ engine to convert equirectangular images into rectilinear format. This command processes example_image.jpg, converting it from an equirectangular format to a rectilinear view. But you can use any other reference image as long as it is equirectangular. Run the example as:

cd $LIBPANORAMA_PATH/libpanorama
./builddir/examples/equirectangular_to_rectilinear $SAMPLES/example_image.jpg

3. For this example you can use the interactive controls with the Spherical Video PTZ (Pan-Tilt-Zoom) for dynamic exploration of panoramic images. Hit the specified keys when the example is running:

• Zoom In/Out: Adjust the zoom level to get a closer view or a wider perspective of the image.
  • In: i
  • Out: o
• Pan Left/Right: Rotate the view horizontally to explore the left or right sides of the panoramic image.
  • Left: 4
  • Right: 6
• Tilt Up/Down: Adjust the vertical angle of the camera to look up or down within the panoramic image.
  • Up: 8
  • Down: 2

4. press the Esc key to exit the program.

Spherical Video PTZ Engine

Description of how to use the engine

GstRrPanoramaptz

After Building and Installation, follow these steps:

The GstRrPanoramaptz plugin allows for real-time PTZ adjustments on panoramic video feeds, enabling users to explore video scenes in greater detail or from different perspectives.

Overview

Features

• CUDA-accelerated PTZ transformations: Leverage the power of NVIDIA CUDA technology. This acceleration helps with a smooth and high-performance video processing.
• Support for RGBA video format.
• Dynamic parameter adjustments: Users can dynamically adjust PTZ parameters such as pan, tilt, and zoom during playback, providing a versatile and interactive video experience.

Properties

The GstRrPanoramaptz plugin introduces three primary properties for real-time video manipulation:

• Pan (Horizontal Rotation): Adjusts the video feed's horizontal orientation. Pan adjustments allow viewers to rotate the video around its vertical axis, simulating a left or right looking direction.
  • Syntax: pan=<value>.
  • Range: -360 to 360 degrees.
  • Default: 0.

• Tilt (Vertical Rotation): This property adjusts the vertical viewing angle of the video feed. It simulates a vertical rotation of the camera view.
  • Syntax: tilt=<value>.
  • Range: -360 to 360 degrees.
  • Default: 0.

• Zoom (Vertical Rotation): This property adjusts the zoom level of the video feed. It simulates moving the camera closer or further away from the scene.
  • Syntax: zoom=<value>.
  • Range: 0.1 to 10.
  • Behavior: Zoom out for zoom < 1, Zoom in for zoom > 1.
  • Default: 1.

Caps and Formats

• The plugin accepts and outputs video in the video/x-raw format, utilizing the RGBA color space. This support ensures compatibility with a wide range of video processing scenarios.
• Enhanced performance on NVIDIA hardware is achieved through support for both system memory and NVMM (NVIDIA Multi-Media) memory inputs. This flexibility allows users to optimize their video processing pipelines based on the available hardware resources.

Basic use example

This pipeline creates a test video, then applies a 0.5-degree rotation to the right, tilts it upwards by 0.5 degrees, and enhances the view with a zoom level of 2.

gst-launch-1.0 videotestsrc ! "video/x-raw,width=1920,height=1080" ! rrpanoramaptz pan=0.5 tilt=0.5 zoom=2 ! videoconvert ! autovideosink

You should see an output as the one below:

Libpanorama example

The example uses a standard video, not a panoramic one, causing some distortion, but we'll explore distortion-free examples with equirectangular images soon.