Re: Questions about analysis "radial intensity distribution"

[Liu, Dongfang (NIH/NIAID) [F]]

Dear Martin,

Could you tell me how to get the profiles along each radius "by hand"?

Best regards
Don

> ----------
> From: Martin du Saire
> Reply To: List IMAGEJ
> Sent: Monday, March 6, 2006 1:04 PM
> To: List IMAGEJ
> Subject: Re: Questions about analysis "radial intensity distribution"
>
> If I have understood correctly,  you need to get
> the profiles along each radius "by hand".  For example:
>
> for (j=0; j<nAngles; j++) {
>        makeLine(fX,fY,fX+(profileRadius*cosA[j]),fY+(profileRadius*sinA[j]));
> //    (fX, fY) are the coordinates of the center
> of the object or region you want to profile
> //    cosA and sinA are lookup tables, or you could calculate them on the fly
>        profile = getProfile();
> //    profile now contains the intensities along
> the selected direction for you to use as needed
> }
>
> M
>
>
> At 11:03 AM 3/6/2006, you wrote:
> >Dear Liu:
> >   I don't know if this could be of help, but
> > there is a plug-in called "radial profile" which maybe could help you.
> >
> >   fjam
> >
> >"Liu, Dongfang (NIH/NIAID) [E]" <[hidden email]> escribió:
> >   Dear friends,
> >I am new user of Image J.
> >I am sorry to bother you.
> >I am looking for your help about the analysis of
> >"radial intensity distribution" . The radial
> >intensity distribution I(r) of the flourescence
> >dot was fit for each frame with a nonlinear
> >Levenberg-Marquardt routine to the
> >Gaussian:I(r)=Io exp(-R^2/w^2) +BG, where R is
> >the distance of each pixel to the center of
> >mass. The fitting parameters are Io, w, and BG,
> >where Io is the peak intensity, BG is the
> >background intensity, and w is the measure of
> >the width (the Gauss width). It is very
> >important for us to get the peak intensity and
> >width. some people suggest me to use Plot Profile(Analyze -> Plot.
> >But I think the "plot profile" is not good.
> >Because the concept of "plot profile"---Displays
> >a two-dimensional graph of the intensities of
> >pixels along a line within the image. The x-axis
> >represents distance along the line and the
> >y-axis is the pixel intensity. For rectangular
> >selections, displays a "column average plot",
> >where the x-axis represents the horizontal
> >distance through the selection and the y-axis
> >the vertically averaged pixel intensity
> >I was confused that how to calculate the "radial
> >intensity distribution" in Image Pro Plus or
> >Image J or other software. Could you help me?
> >Advice would be greatly appreciated.
> >I am looking forward to your reply.
> >
> >Thank you very much.
> >Best regards
> >df
> >
> >
> > > ----------
> > > From: Gabriel Landini
> > > Reply To: List IMAGEJ
> > > Sent: Friday, March 3, 2006 12:10 PM
> > > To: List IMAGEJ
> > > Subject: Re: Image transform
> > >
> > > On Friday 03 March 2006 16:25, Liu, Dongfang (NIH/NIAID) [E] wrote:
> > > > Thank you for your help.
> > > > Yes, the system is a miroscope. Could you tell what other optics I should
> > > > consider to calibrate a image?
> > >
> > > No, I couldn't because I do not know what
> > kind of optics your microscope has.
> > >
> > > You have to do this:
> > >
> > > > > You need to put a known
> > > > > sized object under your imaging system
> > and see how many pixels it spans.
> > > > > Then you estimate the size of your pixels
> > dividing the known size of your
> > > > > object by the number of pixels it occupies.
> > >
> > > Cheers,
> > >
> > > Gabriel
> > >
> > >
> >
> >
> >
> >---------------------------------
> >
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> >Llamadas a fijos y móviles desde 1 céntimo por minuto.
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>
>