Reading a RAW file from a hyperspectral camera using ENVI information

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I have captured and stored data that comes from a hyperspectral camera. This results in 2 files:
''example_file.raw''
''example_file.hdr''
I use the function read_envihdr to load ''example_file.hdr'':
example_file.hdr
>> read_envihdr('example_file.hdr')
ans =
struct with fields:
CONTENT: 'ENVI'
file_type: 'ENVI Standard'
sensor_type: 'MONARCH'
wavelength_units: 'nm'
data_type: 12
interleave: 'BSQ'
byte_order: 0
bit_depth: 10
header_offset: 0
wavelength: {10×1 cell}
gain: {10×1 cell}
exposure_time: {10×1 cell}
exposure_type: '{↵radiometric-calibration↵}'
default_bands: {[713]}
lines: 1024
samples: 1280
bands: 10
size: [1024 1280 10]
machine: 'ieee-le'
iscomplex: 0
format: 'uint16'
>>
Now, I don't have much experience reading hyperspectral data. But what I understand so far is that the ENVI standard is more or less required (or at least very handy) to load the *.raw file. Can anybody give me a hint how to proceed further to read the *.raw file now that I have the ENVI standard information available?

Answers (1)

Subhadeep Koley
Subhadeep Koley on 11 Jun 2021
You can use the enviinfo(__) function to read metadata from your ENVI header file (.hdr file), and then you can use multibandread(_) to read the binary .raw file.
% Read ENVI header file
info = enviinfo('example_file.hdr');
% Read the .raw data file
data = multibandread('example_file.raw',[info.Height, info.Width, info.Bands],...
info.DataType, info.HeaderOffset, info.Interleave, info.ByteOrder);
NOTE: The above mentioned fetures (e.g. enviinfo(_)) come under Image Processing Toolbox's Hyperspectral Imaging Library support package, and can be downloaded from here.
For more information on Hyperspectral Imaging Library see the documentation.
  1 Comment
Emma Stewart
Emma Stewart on 5 May 2022
@Subhadeep Koley why this file is not readable with above code? this code is not working here
The HSI file size is bigger than 5 MB (Matlab attachment limit), so i have uploaded the file on drive Link to access image file: https://drive.google.com/drive/folders/1GTSkQMog4EvffH_geeKJun0oX6BCh5zo?usp=sharing
any idea thanks a ton
Emma

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