Radiometric resolution refers to a sensor's ability to distinguish slight differences in energy levels and is measured in bits. More bits allows an image to store more grayscale values, enabling better discrimination between classes. For example, Landsat-8 has 12-bit resolution, allowing it to distinguish over 4,000 grayscale levels and better characterize land cover compared to Landsat-7's 8-bit resolution of 256 levels. Higher radiometric resolution improves a sensor's sensitivity to capture subtle differences in surface reflectance.

1. Radiometric resolution
ASSAM UNIVERSITY, SILCHAR
DEPARTMENT OF EARTH SCIENCE
PRESENTED BY:
KUKI MONJORI BORUAH
MSc. 1ST SEMESTER
ROLL NO-202112
SUBMITTED TO:
Dr. PURBOJYOTI PHUKON
ASSISTANT PROFESSOR

2. CONTENT
 INTRODUCTION
 RADIOMETRIC RESOLUTION
 BIT
 BIT IN RADIOMATRIC RESOLUTION
 APPLICATION OF RADIOMETRIC RESOLUTION
 CONCLUSION
 REFERENCES

3. INTRODUCTION
 Image resolution refers to the ability of a remote sensing system to record and display the
finer details including the quality of data.
 Resolution of a sensor system is its capability to discriminate two closely spaced objects
from each other.
 Varies from sensor to sensor and broadly described as coarse and fine.
 Categorized into four types-
 Spatial resolution (what area & how detailed)
 Spectral resolution (what color bands)
 Temporal resolution (time of day/season/year)
 Rediometric resolution (color depth)

4. RADIOMATRIC RESOLUTION
 Radiometric characterstics describe actual information content in an image.
 Refers to the sensitivity of the sensor to incoming radiance that discriminate very slight differences in
energy.
 Stands for the ability of a digital sensor to distinguish between grey scale values while acquiring an
image.
 The quantisation levels are expressed as n binary bits.
2 bit image 8 bit image

5. WHAT IS BIT?
 Bit depth refers to the color information stored in an
image.
 Each bit records an exponent of power 2.
 In remote sensing bit stands for the number of grey scale
values a sensor can tell apart.
 1 bit image can only show two colors, black and white.
1 2 3 4 5 6 7 8 9 10 11 Number of bits
2 4 8 16 32 64 128 256 512 102
4
2048 Maximum values
8 bits
Exponent of power 2
Higher the bit, more gray scale values

6. BIT IN REDIOMETRIC RESOLUTION
 Radiometric resolution refers to how much information is in a pixel which is expressed in
units of bits.
 Coarse radiometric resolution would record a scene using only a few brightness levels
whereas fine radiometric resolution would record the same scene using many brightness
level.
 In classifying a scene, different classes are more precisely identified if radiometric precision
is high.

7. APPLICATION OF RADIOMETRIC RESOLUTION
• A satellite perceives different wavelengths in different
intensities and can only distinguish between bright and
dark.
• A spectral image is not less than a raster consisting of
different grey-scale values.
• NASA Satellite sensor examples:
o 12 bit sensor (MODIS, MISR, LANDSAT-9
TM/MSS), 4096 levels
o 10 bit sensor (AVHRR), 1024 levels
o 8 bit sensor (LANDSAT-7 TM), 256 levels
o 6 bit sensor (LANDSAT-7 MSS), 64 levels

8.  One improvement will be greater sensitivity. Landsat-7 measures the amount of reflected light
on a scale of 0 to 255 (8 bits), while LDCM (Landsat-8) measure light on a scale of 0 to 4,095
(12 bits). This improvement enable researchers to better characterized land cover and land use
on a global scale.
A portion of the Great Salt Lake, Utah by LS-7 (left) and LS-8 (right)

9. CONCLUSION
 The radiometric resolution of image data in remote sensing stands for the
ability of the sensor to distinguish different grey-scale values.
 It is measured in bits.
 The more bit an image has the more grey-scale values can be stored and thus
more differences in the reflection on the land surface can be spotted.

10. REFERENCES
 Gupta, Ravi P.; 3rd edition; Remote Sensing Geology.
 https://egyankosh.ac.in/bitestream/123456789/39533/1/Unit-5.pdf
 https://appliedsciences.nasa.gov/sites/default/files/D1P3_Fundamentals.pdf
 https://www.coursera.org/lecture/spatial-analysis-satellite-imagery-in-a-
gis/radiometric-resolution-of-satellite-sensors-Y7pkP