Image plot looks blurry

Hii, i am trying to plot a seismic image using the GMT. However the images generated is blurry and to make it higher resolution I tried to change -I option of xyz2grd, however i am not getting higher resolution image. I hope experts will help me overcoming this problem.
what should I have to add in the code so that blurry portion will be clear and illuminated.

I wrote the code as follows


gmt psxy -JX$j1 -R$r1 -K -P -X4.5 -Y10 </dev/null> $ps
cat input.txt| awk ‘{print $2,$1,$3}’ > data
gmt xyz2grd data -Gdata.grd -I1.0/0.25 -R$r1
gmt grd2cpt data.grd -Cpolar -Z > img.cpt
gmt grdimage data.grd -Cimg.cpt -JX$j1 -R$r1 -K -P -O </dev/null>> $ps
gmt psxy -JX$j1 -R$r1 -Ba50f50g500:“no of sensors”:/a5f0g0:“Time (s)”:NseW -P -O -K </dev/null>> $ps

The generated picture is here (37.8 KB)

Hi, I am not sure what you are using to view your file. I downloaded it and opened it in Adobe Illustrator and it does not look blurry but it looks blurry when I use Apple Preview.
What is the spacing of your original data in the time direction? When you use gmt xyz2grd data -Gdata.grd -I1.0/0.25 then you will be limited in the time direction to the 0.25 seconds spacing you specified.
I attach an export of your picture from Illustrator. It is not blurry, but has large blocks in the time direction because of the 0.25 second spacing.

Are you asking the sampling rate?
Sampling rate is 300hz

Try setting yinc (i.e. time) to 1/300 (0.0033(3333…)).