Hi, do you have access to Matlab, or Octave (an open source alternative)? If so, it's quite easy to process the height data into a binary f32 file.
I used a simple script to process .asc NOAA Coastal Relief model data to .f32:
This example takes an ascii text file (in.txt) for the area of interest, with all header information removed, and scales it to 2049x2049, then saves it. You will need to think about how to handle the elevations for the sea area. This example sets everything at 0m or less to -10m.
clear
pkg load image
load 'in.txt';
in = flipud(in); %Flip in north-south direction
scaled = imresize(in,[2049 2049]);
%Do any extra processing here
scaled(scaled<=0) = -10; %This would set any elevations at or below 0 in the raw data to -10m
fileID = fopen('height2049.f32','w');
fwrite(fileID,scaled,'single');
fclose(fileID);