Method and apparatus for generating ultrasound image having enhanced quality
A method of generating an ultrasound image includes acquiring a response signal to an ultrasound wave transmitted to an object, changing a level of the acquired response signal depending on a position and an amplitude of the acquired response signal on a scan line, performing logarithmic compression on the level-changed response signal, and generating an ultrasound image based on the compressed signal.
1. A method of generating an ultrasound image in an ultrasound image generating apparatus having an ultrasound probe, a hardware processor, and a display, by changing a level of a signal on a scan line depending on an acquired position and amplitude of an ultrasound response signal, the method comprising:
acquiring, through the ultrasound probe connected to the ultrasound image generating apparatus, a response signal to an ultrasound wave transmitted to an object;
changing, using the hardware processor of the ultrasound image generating apparatus, a level of the acquired response signal depending on a position and an amplitude of the acquired response signal on a scan line, using a decompression gain that changes based on depth, measured from the ultrasound probe, to enhance a distinction between the response signal and noise generated in the ultrasound image generating apparatus;
performing, using the hardware processor of the ultrasound image generating apparatus, logarithmic compression on the level-changed response signal;
generating, using the hardware processor of the ultrasound image generating apparatus, an ultrasound image based on the compressed signal; and
displaying, on the display of the ultrasound image generating apparatus, the ultrasound image.
2. The method of claim 1 , wherein the changing of the level is performed by multiplying an amplitude of envelop data included in the response signal by a decompression coefficient.
3. The method of claim 2 , wherein the decompression coefficient is determined based on at least one of a decompression value, a dynamic range, a minimum detection level of ultrasound signal amplitude, and an amplitude of envelop data.
4. The method of claim 3 , wherein the decompression value is determined depending on a position of each pixel indicating the ultrasound image.
5. The method of claim 3 , wherein the decompression value is preset according to a predetermined reference or is set in real time according to a user input.
6. The method of claim 2 , wherein the decompression coefficient is determined via the equation below:
α
(
s
,
z
)
=
10
{
(
DR
DR
-
DV
(
s
,
z
)
-
1
)
·
(
20
·
log
10
(
x
(
s
,
z
)
)
)
+
(
1
-
DR
DR
-
DV
(
s
,
z
)
)
·
Min
(
s
,
z
)
}
/
20
where S denotes a scan line position value, z denotes a depth position value, a(s, z) is a decompression coefficient at coordinates (s, z), DR denotes a dynamic range, DV(s, z) denotes a decompression value at coordinates (s, z), MIN(s, z) denotes a minimum detection level of ultrasound signal amplitude at coordinates (s, z), and x(s, z) denotes an amplitude of envelop data at coordinates (s, z).
7. An apparatus for generating an ultrasound image by changing a level of a signal on a scan line depending on an acquired position and amplitude of an ultrasound response signal, the apparatus comprising:
an ultrasound probe;
a display;
a hardware processor; and
a memory storing instructions that, when executed by the hardware processor perform operations comprising:
acquiring, through the ultrasound probe, a response signal to an ultrasound wave transmitted to an object;
changing a level of the acquired response signal depending on a position and amplitude of the acquired response signal on a scan line, using a decompression gain that changes based on depth, measured from the ultrasound probe, to enhance a distinction between the response signal and noise generated in the ultrasound image generating apparatus;
logarithmically compressing the level-changed response signal; and
generating an ultrasound image based on the compressed signal for display on the display.
8. The apparatus of claim 7 , wherein the hardware processor changes the level of the response signal by multiplying an amplitude of envelop data included in the response signal by a decompression coefficient.
9. The apparatus of claim 8 , wherein the decompression coefficient is determined based on at least one of a decompression value, a dynamic range, a minimum detection level of ultrasound signal amplitude, and an amplitude of envelop data.
10. The apparatus of claim 9 , wherein the decompression value is determined depending on a position of each pixel indicating the ultrasound image.
11. The apparatus of claim 9 , wherein the decompression value is preset according to a predetermined reference or is set in real time according to a user input.
12. The apparatus of claim 8 , wherein the decompression coefficient is determined via the equation below:
α
(
s
,
z
)
=
10
{
(
DR
DR
-
DV
(
s
,
z
)
-
1
)
·
(
20
·
log
10
(
x
(
s
,
z
)
)
)
+
(
1
-
DR
DR
-
DV
(
s
,
z
)
)
·
Min
(
s
,
z
)
}
/
20
where S denotes a scan line position value, z denotes a depth position value, a(s, z) is a decompression coefficient at coordinates (s, z), DR denotes a dynamic range, DV(s, z) denotes a decompression value at coordinates (s, z), MIN(s, z) denotes a minimum detection level of ultrasound signal intensity at coordinates (s, z), and x(s, z) denotes an amplitude of envelop data at coordinates (s, z).