Reading FI data from an UFF file recorded from a Verasonics Scanner
In this example we show how to read channel data from a UFF (Ultrasound File Format) file recorded with a Verasonics scanner. You will need an internet connection to download data.
_by Ole Marius Hoel Rindal olemarius@olemarius.net and Alfonso Rodriguez-Molares alfonso.r.molares@ntnu.no
$Last updated: 2017/10/06$
Contents
Checking the file is in the path
To read data from a UFF file the first we need is, you guessed it, a UFF file. We check if it is on the current path and download it from the USTB websever.
close all; % data location url='http://ustb.no/datasets/'; % if not found downloaded from here filename='L7_FI_IUS2018.uff'; % checks if the data is in your data path, and downloads it otherwise. % The defaults data path is under USTB's folder, but you can change this % by setting an environment variable with setenv(DATA_PATH,'the_path_you_want_to_use'); tools.download(filename, url, data_path);
Reading data
Let's first check if we are lucky and the file allready contains beamformed_data that we can display.
display=true;
content = uff.index([data_path filesep filename],'/',display);
UFF: Contents of \\kant\ifi-ansatt-u08\omrindal\Repos\USTB_summer_student_2021\data\L7_FI_IUS2018.uff at / - /b_data: b_data [uff.beamformed_data] size(1,1) - /channel_data: channel_data [uff.channel_data] size(1,1) - /scan: scan [uff.linear_scan] size(1,1)
Channel data
If it doesn't have any beamformed data at least it should have some channel_data. So let's read that.
channel_data=uff.read_object([data_path filesep filename],'/channel_data');
UFF: reading channel_data [uff.channel_data] UFF: reading sequence [uff.wave] [====================] 100%
And then do the normal routine of defining the scan,
x_axis=zeros(channel_data.N_waves,1); for n=1:channel_data.N_waves x_axis(n)=channel_data.sequence(n).source.x; end z_axis=linspace(1e-3,55e-3,512).'; scan=uff.linear_scan('x_axis',x_axis,'z_axis',z_axis);
setting up and running the pipeline
mid=midprocess.das(); mid.dimension = dimension.both(); mid.channel_data=channel_data; mid.scan=scan; mid.transmit_apodization.window=uff.window.scanline; mid.receive_apodization.window=uff.window.tukey25; mid.receive_apodization.f_number=1.7; b_data=mid.go();
USTB General beamformer MEX v1.1.2 .............done!
Display image
And finally display the image.
b_data.plot([],'Beamformed image');
Beamforming with MLA's
MLA = 4; scan_MLA=uff.linear_scan('x_axis',linspace(x_axis(1),x_axis(end),length(x_axis)*MLA)','z_axis',z_axis); mid_MLA=midprocess.das(); mid_MLA.dimension = dimension.both(); mid_MLA.channel_data=channel_data; mid_MLA.scan=scan_MLA; mid_MLA.transmit_apodization.window=uff.window.scanline; % We are using the hybrid transmit delay model. See the reference below: % Rindal, O. M. H., Rodriguez-Molares, A., & Austeng, A. (2018). A simple , artifact-free , virtual source model. % IEEE International Ultrasonics Symposium, IUS, 1–4. mid_MLA.spherical_transmit_delay_model = spherical_transmit_delay_model.hybrid; mid_MLA.transmit_apodization.MLA = MLA; mid_MLA.transmit_apodization.MLA_overlap = 1; mid_MLA.receive_apodization.window=uff.window.tukey25; mid_MLA.receive_apodization.f_number=1.7; b_data_MLA=mid_MLA.go(); b_data_MLA.plot([],'Beamformed image MLA');
USTB General beamformer MEX v1.1.2 .............done!