Skip to main content

QuickBird. AVIRIS




QuickBird and AVIRIS


1. QuickBird:

   - QuickBird is a commercial high-resolution Earth observation satellite system launched by DigitalGlobe in 2001.

   - Spatial Resolution: It is known for its very high spatial resolution, with panchromatic (black and white) imagery at 61 centimeters and multispectral imagery at 2.44 meters.

   - Spectral Bands: QuickBird is equipped with multispectral sensors, which means it captures imagery in multiple spectral bands, including visible, near-infrared, and short-wave infrared.

   - Applications: QuickBird data is used for various applications, such as urban planning, land cover mapping, disaster management, and environmental monitoring. Its high spatial resolution makes it suitable for detailed feature extraction and analysis in urban and natural environments.

   - Availability: QuickBird data was widely used by commercial and government entities for both civil and defense purposes. However, it's important to note that satellite missions have lifespans, and data availability may have changed since my last knowledge update in September 2021.


2. AVIRIS (Airborne Visible/Infrared Imaging Spectrometer):

   - AVIRIS is an airborne remote sensing instrument designed to capture high-resolution spectral data.

   - Spectral Resolution: It offers high spectral resolution, covering a wide range of wavelengths from visible to short-wave infrared.

   - Applications: AVIRIS is often used for geological and environmental studies, mineral exploration, vegetation analysis, and atmospheric research. Its ability to capture detailed spectral signatures helps scientists and researchers identify and study various materials and components on the Earth's surface.

   - Flexibility: Unlike satellites, AVIRIS is mounted on aircraft, providing flexibility in data collection. Researchers can target specific areas of interest for detailed spectral analysis.

   - Scientific Research: AVIRIS has contributed significantly to scientific research in fields such as geology, agriculture, forestry, and climate science by providing rich spectral data for analysis.

   - Availability: AVIRIS data is typically acquired through airborne campaigns conducted by research institutions and agencies. Availability may vary depending on specific research projects and campaigns.


In summary, QuickBird is a high-resolution commercial satellite known for its detailed imagery and multispectral capabilities, while AVIRIS is an airborne imaging spectrometer designed for capturing high-resolution spectral data. Both instruments have played significant roles in remote sensing, contributing to various scientific, environmental, and commercial applications. Please note that the availability and specific details of these systems may have evolved since my last knowledge update in September 2021.

Comments

Popular posts from this blog

Photogrammetry – Types of Photographs

In photogrammetry, aerial photographs are categorized based on camera orientation , coverage , and spectral sensitivity . Below is a breakdown of the major types: 1️⃣ Based on Camera Axis Orientation Type Description Key Feature Vertical Photo Taken with the camera axis pointing directly downward (within 3° of vertical). Used for maps and measurements Oblique Photo Taken with the camera axis tilted away from vertical. Covers more area but with distortions Low Oblique: Horizon not visible High Oblique: Horizon visible 2️⃣ Based on Number of Photos Taken Type Description Single Photo One image taken of an area Stereoscopic Pair Two overlapping photos for 3D viewing and depth analysis Strip or Mosaic Series of overlapping photos covering a long area, useful in mapping large regions 3️⃣ Based on Spectral Sensitivity Type Description Application Panchromatic Captures images in black and white General mapping Infrared (IR) Sensitive to infrared radiation Veget...

Photogrammetry – Geometry of a Vertical Photograph

Photogrammetry is the science of making measurements from photographs, especially for mapping and surveying. When the camera axis is perpendicular (vertical) to the ground, the photo is called a vertical photograph , and its geometry is central to accurate mapping.  Elements of Vertical Photo Geometry In a vertical aerial photograph , the geometry is governed by the central projection principle. Here's how it works: 1. Principal Point (P) The point on the photo where the optical axis of the camera intersects the photo plane. It's the geometric center of the photo. 2. Nadir Point (N) The point on the ground directly below the camera at the time of exposure. Ideally, in a perfect vertical photo, the nadir and principal point coincide. 3. Photo Center (C) Usually coincides with the principal point in a vertical photo. 4. Ground Coordinates (X, Y, Z) Real-world (map) coordinates of objects photographed. 5. Flying Height (H) He...

Raster Data Structure

Raster Data Raster data is like a digital photo made up of small squares called cells or pixels . Each cell shows something about that spot — like how high it is (elevation), how hot it is (temperature), or what kind of land it is (forest, water, etc.). Think of it like a graph paper where each box is colored to show what's there. Key Points What's in the cell? Each cell stores information — for example, "water" or "forest." Where is the cell? The cell's location comes from its place in the grid (like row 3, column 5). We don't need to store its exact coordinates. How Do We Decide a Cell's Value? Sometimes, one cell covers more than one thing (like part forest and part water). To choose one value , we can: Center Point: Use whatever feature is in the middle. Most Area: Use the feature that takes up the most space in the cell. Most Important: Use the most important feature (like a road or well), even if it...

Photogrammetry

Photogrammetry is the science of taking measurements from photographs —especially to create maps, models, or 3D images of objects, land, or buildings. Imagine you take two pictures of a mountain from slightly different angles. Photogrammetry uses those photos to figure out the shape, size, and position of the mountain—just like our eyes do when we see in 3D! Concepts and Terminologies 1. Photograph A picture captured by a camera , either from the ground (terrestrial) or from above (aerial or drone). 2. Stereo Pair Two overlapping photos taken from different angles. When seen together, they help create a 3D effect —just like how two human eyes work. 3. Overlap To get a 3D model, photos must overlap each other: Forward overlap : Between two photos in a flight line (usually 60–70%) Side overlap : Between adjacent flight lines (usually 30–40%) 4. Scale The ratio of the photo size to real-world size. Example: A 1:10,000 scale photo means 1 cm on the photo...

Logical Data Model in GIS

In GIS, a logical data model defines how data is structured and interrelated—independent of how it is physically stored or implemented. It serves as a blueprint for designing databases, focusing on the organization of entities, their attributes, and relationships, without tying them to a specific database technology. Key Features Abstraction : The logical model operates at an abstract level, emphasizing the conceptual structure of data rather than the technical details of storage or implementation. Entity-Attribute Relationships : It identifies key entities (objects or concepts) and their attributes (properties), as well as the logical relationships between them. Business Rules : Business logic is embedded in the model to enforce rules, constraints, and conditions that ensure data consistency and accuracy. Technology Independence : The logical model is platform-agnostic—it is not tied to any specific database system or storage format. Visual Representat...