Imaging Parameters

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There is an abundance of imaging parameters that control the system; they will not all be explored here. However, an overview of how the system works will be demonstrated.

Research Menus[edit]

In addition to the parameters that can be adjusted from the console and touchscreen, there are many research menus that contain lower-level parameters that play a role in image formation and processing.

A research menu is split into 3 areas:

  1. The parameter list
  2. The parameter description
  3. The current menu title

When a parameter is clicked on, the description will update on the menu. To change a parameter value or the active menu, highlight the parameter or menu title and use one of the following to scroll:

  • Mouse wheel with externally plugged-in mouse
  • Audio knob on the Sonix RP or Sonix MDP systems
  • Menu Param button on the SonixTOUCH touchscreen
Rpmenu.jpg

Main Screen Parameters[edit]

Parameter Description Unit
B Optimization Updates frequency, receive filters and other parameters to optimize the image for certain settings. Displayed on screen as ‘Penetration’, ‘General’, ‘Resolution’, or ‘Harmonics’. N/A
Freq The displayed frequency. Changed through the B Optimization. MHz
Depth The depth to acquire B or RF data. cm
Sector The percentage of the vectors being acquired, as a maximum of the line density. %
Gain The overall B image gain. %
FR The frame-rate optimization. Automatically adjusts the line density. N/A
FPS The acquisition rate in frames per second. Hz
Dyn Adjusts dynamic range by altering the log compression table after envelope detection. dB
Persist The frame averaging level. N/A
Map The greyscale map index that adjusts brightness, contrast and gamma. N/A
Chroma The chroma index to colorize the image. N/A
Power The power level, where 0 is the max power in volts. N/A
Acoustic Reading The MI/TI readings that adhere to the AIUM/NEMA standards. N/A
Clarity Level of the image-enhancement filter. N/A

VCA Parameters[edit]

Parameter Description Unit
VCA Amplification Amplification setting sent to the VCA - see VCA datasheet for system version (RP/TouchV3/TouchV4) N/A
VCA LPF Sets the cutoff frequency of the low-pass filter on the VCA. V2 (VCA2612): 0 = off, 1 = on. V4 (AFE): 0 = 10MHz, 1 = 15MHz, 2 = 20MHz, 3 = 30MHz N/A
VCA Input Clamp LNA voltage clamp. 800 = 800mVpp, 1200 = 1.2Vpp, 1600 = 1.6Vpp. N/A
VCA Active Termination VCA active termination used to reduce reflection from mismatches and achieving better axial resolution. 0 = off, 1 = 50 Ohm, 2 = 100 Ohm, 3 = 200 Ohm, 4 = 400 Ohm. N/A

Color Doppler Parameters[edit]

General CDI Parameters

Parameter Description Range
color-baseline Baseline for the color velocity map. (-125 to 125)
color-priority The color priority that is applied against the B map 0 to 250
color-median param The median filter method applied to color data.
color-velocity min display The minimum velocity value the Doppler signal must have in order to be considered true flow. This parameter is applied to the map level in post-processing, and is not part of the regular Doppler threshold processing. 0 to 100
color-blur (NOT USED) Applies the average filter selection to the color data. 0 to 8
color-median turn on/off median filter on color processing 0 = off 1 = on. 0 to 1
color-temporal filter

(NOT USED)

color-persistence The number of frames to apply frame averaging on the color image. 0 to 9

Adaptive Filter Parameters

Parameter Description Range
color-adapt window sz Window size of adaptive filter 3 to 15
color-adapt method Adaptive filter method. 0 = average, 1 = median
color-adapt scale Scale factor of adaptive filter. 0 to 100
color-adapt minmax discard Discarded samples min/max errors for adaptive filter. 0 to 100

Sticks Filter Parameters

Parameter Description Range
sticks filter size Scale factor for the sticks filter. 3 to 15
sticks window size Sticks filter window size. 1 to 15
sticks method Sticks filter method. 0 to 10

Post Processing Filter Parameters (applied to post scan converted color image)

Parameter Description Range
post-asr smooth level ASR filter smooth level. 0 to 40
post-asr line strength ASR filter smooth level. 0 to 50
post-asr lp cut ASR low pass cutoff (applied to color data). 1 to 150
post-asr contrast ASR contrast. 0 to 40
post-asr thresh ASR threshold. 0 to 31
pre-asr weight color ASR weight. 0 to 40
color-edge smooth Smooths the color edges so that on the edges the speed value phases out. 0 = off, 1 = on
color-persistence after sc Persistence of color data. 0 to 10

Post Processing Filter Parameters (applied to power doppler image using same filter method as above)

Parameter Description Range
pre-asr smooth level ASR filter smooth level parameter applied to prescan converted data. 0 to 40
pre-asr weight ASR filter weight parameter applied to prescan converted data. 0 to 40
pre-asr line strength ASR filter line strength parameter applied to prescan converted data. 0 to 50
pre-asr lp cut ASR low pass cutoff applied to prescan converted data. 1 to 150
pre-asr contrast ASR contrast applied to prescan converted data. 0 to 40
pre-asr thresh ASR threshold applied to prescan converted data. 0 to 31
post-asr power lp cut ASR low pass cutoff applied to postscan converted data. 1 to 150

Color Threshold Parameters

Parameter Description
color-r0 min Minimum R0 value the signal must have in order to be considered real flow. Velocities below this value are ignored.
color-r0 clutter max Maximum R0 clutter value the Color Doppler signal can have before it is discarded. 0 means it is not used
color-r0 clutter max power Maximum R0 clutter value the Power Doppler signal can have before it is discarded. 0 means it is not used.
color-velocity min The minimum velocity value the Doppler signal must have in order to be considered true flow.
power-r0 shift The shift value applied to R0, before R0 gets interpolated to the color map (0 to 31).
color-sigma max Maximum sigma value the Doppler signal can have before it is discarded. 0 means it is not used

color-r0 max.

color-r0 minmax thresh The maximum r0 value to set. Any r0 above this value will be set to this parameter value.
color-r0 min noise Threshold for r0 noise. Works with the variable “color-vel max noise” Signals with low R0 and with high velocity (likely to be noise).
color-vel max noise Threshold for velocity noise. Works with “color-r0 min noise” Signals with low R0 and with high velocity is likely to be noise.

Presets[edit]

Imaging presets are stored in the C:\Program Files\Ultrasonix\Exam\presets\ folder. Variable IDs are string values. All the variables that are used within the software are stored in the file imaging.lst.xml. This file includes a description of each variable (if available) as well as the research menu where the parameter can be found.

An example of the B frequency parameter in the imaging.lst.xml is shown below. The unit for the b-freq parameter is in MHz, and the menu which it can be found is the B TX research menu in exam.

 <variable id="b-freq" name="Tx Frequency" type="integer">
      <unit disp="MHz">Hz</unit>
      <desc>Transmit frequency for B imaging</desc>
      <category root="B" sub="TX"/>
      <lock>
        <type>freeze</type>
      </lock>
 </variable>

The file imaging.set.xml contains variable boundaries and default image settings. These default settings are used when a parameter is not found in the Gen-General .xml preset for a probe. An example of the b-freq parameter in the imaging.set.xml file is shown below. Here, the default value is 10MHz while the boundary of the file is specified as a range from 1MHz to 10MHz in increments (steps) of 0.5MHz.

<variable id="b-freq" value="10000000">
        <range start="1000000" step="500000" stop="10000000"/>
</variable>

For each probe, there is a Gen-General preset that is stored in the C:\Program Files\Ultrasonix\Exam\presets\imaging\ folder. The Gen-General preset file is the master preset which contains the default image settings for a particular probe. When a preset is loaded (eg. MSK-General (L14-5 38mm).xml), the software first loads the settings from the Gen-General preset .xml file to get the default parameters and then loads the additional parameters in the MSK-General (L14-5 38mm).xml file.