MATLAB读取高光谱数据
只能读取dat类型的高光谱数据
以下为头文件
clc
clear all
close all
hdr = read_envihdr('d.hdr');
Image = multibandread('d.dat', hdr.size, [hdr.format '=>double'], hdr.header_offset, hdr.interleave, hdr.machine);
Image= reshape(Image,hdr.samples*hdr.lines,hdr.bands);
以下为子函数：
function info = read_envihdr(hdrfile)
% READ_ENVIHDR read and return ENVI image file header information.
% INFO = READ_ENVIHDR('HDR_FILE') reads the ASCII ENVI-generated image
% header file and returns all the information in a structure of
% parameters.
%
% Output:
% * Info - struct with fields provided in the ENVI file. ENVI header
% format requires the following fields:
% * samples - number of samples in the image (columns)
% * lines - number of lines in the image (rows)
% * bands - number of bands in the image. If all 3 dimensions are
% provided than info.size will be created holding
% [info.lines info.samples info.bands]
% * data_type - data type of the image stored as an integer in 1-15
% range. If provided than info.format will be created holding string
% with Matlab's type name.
% * interleave - file band interleave type; either bip, bsq, or bil are
% possible
% * byte_order - byte order (0 is little endian [least significant
% byte first], 1 is big endian [most significant byte first]).
% If provided than info.machine will be created holding either
% 'ieee-le' or 'ieee-be' string.
%
% Example 1:
% >> info = read_envihdr('my_envi_image.hdr')
% info =
% description: [1x101 char]
% samples: 658
% lines: 749
% bands: 3
% size: [749 658 3]
% header_offset: 0
% file_type: 'ENVI Standard'
% data_type: 4
% format : 'single'
% interleave: 'bsq'
% sensor_type: 'Unknown'
% byte_order: 0
% map_info: [1x1 struct]
% projection_info: [1x102 char]
% wavelength_units: 'Unknown'
% pixel_size: [1x1 struct]
% band_names: [1x154 char]
% Example 2:
% >> info = read_envihdr('my_envi_image.hsi');
% >> Z = multibandread(gFile, info.size, [info.format '=>double'], ...
% >> info.header_offset, info.interleave, info.machine);
%
% Author: Jarek Tuszynski ([email protected])
% License: BSD (Berkeley Software Distribution)
%
% See Also
% * MATLAB function multibandread
% * http://geol.hu/data/online_help/ENVI_Header_Format.html
%% If file does not have 'hdr' extension than check if there is an matching
% header file
[FilePath, FileRoot, FileExt] = fileparts(hdrfile);
if ~strcmp(FileExt, '.hdr')
fname = hdrfile;
hdrfile = [fname '.hdr']; % add '.hdr' to the file name
if ~exist(hdrfile,'file')
hdrfile = [FilePath '\' FileRoot '.hdr']; % replace extension
if ~exist(hdrfile,'file')
hdrfile = fname;
end
end
end
%% Load whole header file into a string
fid = fopen(hdrfile);
if fid<0, error('%s does not exist. \n', hdrfile); end
str = fread(fid,'uint8=>char')';
fclose(fid);
%% split string into lines
flag = 0;
str(str==10) = 13;
str=strrep(str,char([13 13]), char(13));
for i = 1:length(str)
switch str(i)
case '{'
flag=flag+1;
case 13
if (flag), str(i)=10; end
case '}'
flag=flag-1;
end
end
lines = textscan(str,'%s','Delimiter',char(13));
lines = lines{1};
%% parse each line into a field of a struc
info = [];
for iLine=1:length(lines)
[info param] = ParseLine(lines{iLine}, info);
if ~isempty(param) && ischar(info.(param)) && nnz(info.(param)=='{')
% if "{" found than parse one more level
line = info.(param);
if nnz(info.(param)=='=')==0 % string has no "=" -> check if it is numeric array
line(line<32) = [];
line(line == '{') = '[';
line(line == '}') = ']';
num = str2num(line); %#ok
if isnumeric(num) && ~isempty(num)
info.(param) = num;
elseif nnz(info.(param)==',')>0 % string has "," -> split into string cell array
line(line == '[' | line == ']') = [];
lines2 = textscan(line,'%s','Delimiter',',');
info.(param) = lines2{1};
end
else % string has "="
line(line == '{' | line == '}') = [];
lines2 = textscan(line,'%s','Delimiter',char(10));
lines2 = lines2{1};
info2 = [];
for jLine=1:length(lines2)
info2 = ParseLine(lines2{jLine}, info2);
end
info.(param) = info2;
end
end
end
%% create info.size
if isfield(info, 'lines') && isfield(info, 'samples') && isfield(info, 'bands')
info.size = [info.lines info.samples info.bands];
end
%% fix 'byte_order' field
if isfield(info,'byte_order')
switch info.byte_order
case 0
info.machine = 'ieee-le';
case 1
info.machine = 'ieee-be';
otherwise
info.machine = 'n';
end
end
%% fix 'data_type' field
if isfield(info,'data_type')
info.iscomplex=false; %if it is complex
switch info.data_type
case 1
info.format = 'uint8';
case 2
info.format= 'int16';
case 3
info.format= 'int32';
case 4
info.format= 'single';
case 5
info.format= 'double';
case 6
info.iscomplex=true;
info.format= 'single';
case 9
info.iscomplex=true;
info.format= 'double';
case 12
info.format= 'uint16';
case 13
info.format= 'uint32';
case 14
info.format= 'int64';
case 15
info.format= 'uint64';
otherwise
error(['File type number: ',num2str(dtype),' not supported']);
end
end
function [struc param] = ParseLine(line, struc)
param='';
eqsn = find(line=='=',1,'first'); % find = sign
if ~isempty(eqsn)
param = strtrim(line(1:eqsn-1));
param(strfind(param,' ')) = '_';
param = genvarname(param); % split line into param
value = strtrim(line(eqsn+1:end)); % and value
if strcmp(param,upper(param)) % is all letters are upper case than ...
param = lower(param); % convert to lower case string
end
% save values as fields of a struct
try
struc.(param) = eval(value); % try converting to numbers, etc.
catch ME %#ok
struc.(param) = value;
end
else
struc.CONTENT = line;
end