MATLAB: How to import hex values from text file

dlmreadfscanfimporting hex datatext file

Hi, I have a text file of hex values in the format of '3D 3D 3D 3E 41' etc.. and want to import to a matrix in order to use inshow(Matrix) to reconstruct the image of the data. It is 1280 values in a row and 1024 columns (1280px X 1024 px image). I have tried fscanf and dlmread but they are not working as I expect. dlmread is not recognizing the first value and fscanf does not read the data in the way that I want when I use [1280 1024]. Examples below:
3D 3D 3D 3C 3E 3A 40 3C 3E 3C 3D 3B 3B 3C 3D 3C 3C 3C 3C 3D 3D 3B 3B 3D 3F 3B 3D 3E 3D 3C 3F 3C 3D 3C 3E 3E 3F 3C 40 3E 40 3D 3E 3D 3E 3D 3E 3B 3C 3B 3D 3D 3D 3D 40 3B 3D 3D 42 3D 3C 3B 3D 3C 3D 3B 3C 3B 3B 3C 3B 3E 3F 3D 3E 3D 3E 3E 40 3C 3E 3D 3D 3C 3D 3C 3D 3D 3F 3B 3A 3B 3C 3D 3F 3B 3C 3D 3D 3B 3B 3A 3B 3C 3B 3B 39 3B 3C 3C 3B 3D 3E 3D 3D 3A 3C 3D 3F 3D 3D 3D 3B 3C 3E 3A 3C 3E 3D 3B 3D 3B 3E 3C 3B 3D 3C 3C 3C 3A 3D 3C 3C 3B 3D 3C 3B 3C 3B 3C 3C 3C 3D 3C 3D 3D 3A 3B 40 3C 3D 3B 3E 3D 3B 3A 3D 3A 3E 3E 3D 3B 3E 3D 3C 3B 3E 3B 3E 3E 3D 3D 3B 3A 3E 3C 3D 3C 3D 3C 3B 3A 3E 3A 3C 3D 3C 3E 3D 3E 3D 3D 3D 3B 3B 3A 3D 3A 3C 3B 3D 38 3A 39 3B 3B 3E 3A 3D 3D 3D 3A 3C 3C 3E 3A 3D 3A 3C 3A 3B 38 3C 3A 3D 3C 3D 3B 39 3B 3A 3B 3D 3A 3B 39 3F 3A 3E 3C 3D 3B 3B 3C 38 39 3A 39 3B 39 3D 3C 3A 3A 3E 3B 3D 3B 3E 3B 3D 3D 3A 3B 3E 3E 3E 39 3E 3B 3A 39 3E 3C 39 39 3D 39 3C 3A 38 3A 3A 3E 3B 3B 3C 3B 3A 3A 3C 3B 3D 3B 3D 3B 3A 39 3C 3A 3C 3C 3A 3A 3B 3A 3C 38 3D 3C 3C 3A 3B 3A 3B 3B 3B 3A 3D 3A 3B 3A 3B 3C 3B 38 3B 39 3B 39 3E 39 3C 3B 3A 3B 3B 39 3C 3C 3A 3A 3A 3A 3A 38 3E 39 3C 3B 3D 3E 3C 39 39 39 3E 3B 3C 3A 39 39 3B 37 39 3B 3C 3C 3D 37 3A 3A 38 3C 3B 3A 3A 3A 3A 39 39 39 3C 38 3C 3B 3D 3C 39 3B 3C 3A 3A 3B 3C 3A 3A 3A 3A 37 3B 38 39 39 39 3A 39 39 39 3A 3A 3B 3C 3B 3D 39 3E 3A 3B 39 3A 3B 3C 3C 3C 37 39 3A 3C 35 3B 39 39 39 39 3B 3C 3A 39 3A 3A 3C 3D 3A 3C 3A 3B 3C 3C 3A 3B 3B 39 39 39 3C 3D 3A 3A 39 3D 3B 3B 3A 3A 38 37 3A 39 3A 3A 37 3A 3A 3B 37 3A 3A 3A 37 3D 3A 3C 39 3D 38 3C 37 3A 39 3B 3A 3B 3A 3C 3A 3B 39 3C 3C 3A 3A 39 39 38 3A 3A 3A 3B 38 37 3B 39 39 3A 39 37 3B 3A 3A 39 38 39 39 3C 3A 3A 3A 3A 38 3B 3C 38 3A 39 3A 3A 3B 38 38 39 3A 3B 3A 39 38 3A 39 3B 36 3A 37 3A 3A 3A 38 39 37 38 38 3B 38 3B 39 3B 38 3A 38 37 36 3B 38 39 3B 39 3A 39 39 3A 3B 3C 38 3A 38 38 39 38 39 3A 39 39 39 3B 3B 3D 39 39 38 38 38 3A 37 39 39 38 38 3B 39 3A 38 38 34 39 36 39 38 39 38 39 38 3A 37 39 37 39 35 38 37 37 39 39 37 38 38 38 39 38 37 37 37 39 39 38 37 39 39 39 37 3A 37 39 38 3A 36 38 38 39 39 3A 37 3C 39 39 39 36 37 36 37 37 37 37 37 37 37 37 37 39 37 37 37 3B 36 38 36 39 36 39 38 38 38 39 34 37 38 3A 37 38 39 3A 38 39 36 39 37 37 38 3A 37 39 39 3B 38 39 38 37 36 37 37 38 36 39 36 36 35 36 36 37 35 36 36 37 35 36 37 37 36 3A 37 36 35 35 37 36 37 37 38 36 35 35 36 37 35 37 37 38 38 37 39 3A 35 37 36 39 37 38 37 36 35 37 35 35 35 37 35 37 38 37 35 37 36 37 34 3A 34 36 39 3A 37 37 36 38 34 35 35 36 34 37 36 34 37 36 35 37 34 35 34 36 37 38 35 35 35 34 34 38 37 35 36 37 33 35 32 33 34 36 34 36 37 35 34 35 34 36 35 34 34 37 36 35 35 34 33 37 34 35 32 35 35 38 33 35 34 34 33 38 34 32 34 34 32 36 34 36 33 35 35 33 33 36 31 36 33 36 34 34 33 36 31 33 33 35 33 34 33 36 34 33 33 37 33 35 34 34 34 34 31 33 32 34 33 34 33 35 33 34 31 32 33 33 33 35 35 34 32 34 32 34 34 30 32 32 30 34 32 34 31 33 33 34 30 34 32 33 33 32 32 31 31 33 32 33 31 34 32 2F 33 32 2F 32 31 33 2F 34 32 33 31 32 2E 30 31 32 31 31 31 34 31 34 32 32 30 33 2E 31 2F 31 30 33 31 31 30 31 30 30 30 32 31 33 31 32 2F 30 30 32 31 2F 2E 30 30 32 30 31 2F 30 2F 31 30 32 2F 2F 32 31 2F 2F 2F 31 2F 30 2E 2F 2F 2F 30 30 30 30 2F 2D 2F 30 2C 2E 2C 30 2D 2F 2F 31 2F 2F 2E 2F 2E 2E 2F 31 31 2F 2C 30 2F 31 2C 30 31 2D 2D 2E 2F 2D 2D 2D 2D 2F 2D 2E 2B 2E 2D 2D 2D 2E 2D 2E 2C 2A 2D 2E 2E 2D 2C 2D 2B 2C 2E 2C 2B 2D 2A 2A 2D 2C 2B 2E 2B 2B 29 2D 2B 2B 2B 2D 2B 2B 2C 2C 2D 2B 2C 2C 2A 2C 2B 2C 2C 2C 2A 2B 29 2B 2A 2B 29 2A 29 2A 29 2C 2A 2A 27 2B 27 2C 28 2A 29 2B 29 2B 2A 29 2B 2A 2B 2A 28 2A 2B 29 2A 2A 27 2A 27 2A 2B 2B 28 2A 28 29 27 29 28 2A 27 29 28 28 28 27 29 29 26 27 29 2A 28 2A 28 29 26 28 27 28 26 27 26 2A 28 28 27 26 28 28 26 28 2A 27 27 27 28 27 27 26 27 26 27 27 27 29 25 27 25 27 24 26 26 28 28 26 25 27 24 28 25 27 25 25 25 26 24 26 24 26 25 25 24 25 24 25 22 23 25 24 23 25 23 25 24 23 22 23 22 25 21 24 23 23 22 23 22 22 22 25 21 24 23 23 21
3D 3D 3D etc...
This is one row of the data in hex. A fair few, say 20, spaces follow the end and another begins right below.
fscanf I was using:
fid = fopen('cb130.dat');
cb130mat = fscanf(fid,'%x');
fclose(fid);
dlmread I was using:
cb130mat = dlmread('cb130.dat');
This is the error that showed:
Mismatch between file and format string. Trouble reading number from file (row 1u, field 1u)
Thanks for the help.

Best Answer

EDIT: I updated my answer with comments and made it a little more efficient.
 buf = fileread( 'chromebackground_0_150810-144439.csv' ) ;
 % - Keep only relevant characters.
 buf = buf(buf>47) ;
 % - Cast to double (makes the following faster).
 buf = buf + 0 ;
 % - Map '0'-'9' to 0-9 and 'A'-'F' to 10-15.
 idNum = buffer < 58 ;
 buf(idNum)  = buf(idNum)  - 48 ; 
 buf(~idNum) = buf(~idNum) - 55 ; 
 % - Build dec value from components and shape as rectangular array.
 img = reshape( [16, 1] * reshape(buf, 2, []), 1280, [] ) ;
=====[ FORMER ]=========================================================
Does the following work?
 buffer = fileread( 'cb130.dat' ) ;
 buffer(buffer<48) = [] ;
 idNum = buffer < 58 ;
 buffer(idNum)  = buffer(idNum)  - 48 ; 
 buffer(~idNum) = buffer(~idNum) - 55 ; 
 img = reshape( [16, 1] * reshape( buffer, 2, [] ), 1280, [] ) ;
You may have to transpose the output or to reshape with 1024 rows because it is not very clear from your question how it is ordered in the file.
Note that it's worrisome if it works, because you are using 3 times the space needed to store the data that define your image.
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