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Wavelet toolbox for complex images

Started by Sylvia March 5, 2010
I am searching for a robust wavelet based MATLAB toolbox that could be used
for complex images. There are some good toolboxes available however they
can only work for real images. 
Thanks
Sylvia
Sylvia wrote:
> I am searching for a robust wavelet based MATLAB toolbox that could be used > for complex images. There are some good toolboxes available however they > can only work for real images. > Thanks > Sylvia
I know what complex numbers are, but what is a complex image? Can it be reproduced by printing? Jerry -- Blaise Pascal: Men never do evil so completely and cheerfully as when they do it from religious conviction. ��������������������������������������������������������������
By complex image, i meant image having its values as complex numbers
instead of real numbers. This is possible when I get data not directly in
image domain but in another complex domain (Fourier for example). 

>Sylvia wrote: >> I am searching for a robust wavelet based MATLAB toolbox that could be
used
>> for complex images. There are some good toolboxes available however
they
>> can only work for real images. >> Thanks >> Sylvia > >I know what complex numbers are, but what is a complex image? Can it be >reproduced by printing? > >Jerry >-- >Blaise Pascal: Men never do evil so completely and cheerfully >as when they do it from religious conviction. >�������������������������������������������������������������� >
On Fri, 05 Mar 2010 11:34:57 -0500, Jerry Avins <jya@ieee.org> wrote:

>Sylvia wrote: >> I am searching for a robust wavelet based MATLAB toolbox that could be used >> for complex images. There are some good toolboxes available however they >> can only work for real images. >> Thanks >> Sylvia > >I know what complex numbers are, but what is a complex image?
I'm told that the image Lena is pretty complex in that it makes you imagine things if you see the non-existant parts. -- Muzaffer Kal DSPIA INC. ASIC/FPGA Design Services http://www.dspia.com
The lena image is not complex in a sense its values are all real numbers. I
am not talking about complexity, but about an image whose values are
complex numbers instead of real value intensities.
>On Fri, 05 Mar 2010 11:34:57 -0500, Jerry Avins <jya@ieee.org> wrote: > >>Sylvia wrote: >>> I am searching for a robust wavelet based MATLAB toolbox that could be
used
>>> for complex images. There are some good toolboxes available however
they
>>> can only work for real images. >>> Thanks >>> Sylvia >> >>I know what complex numbers are, but what is a complex image? > >I'm told that the image Lena is pretty complex in that it makes you >imagine things if you see the non-existant parts. >-- >Muzaffer Kal > >DSPIA INC. >ASIC/FPGA Design Services > >http://www.dspia.com >
Jerry Avins <jya@ieee.org> wrote:
> Sylvia wrote: >> I am searching for a robust wavelet based MATLAB toolbox that could be used >> for complex images. There are some good toolboxes available however they >> can only work for real images.
> I know what complex numbers are, but what is a complex image? > Can it be reproduced by printing?
I don't know about complex, but there are some cases in optics where phase information is important. If you represent amplitude and phase as a complex number then that would count. Holography, in some sense, stores both the amplitude and phase of the reflected beam, and holograms are difficult to reproduce by intensity based reproduction systems. -- glen
glen herrmannsfeldt wrote:
> Jerry Avins <jya@ieee.org> wrote: >> Sylvia wrote: >>> I am searching for a robust wavelet based MATLAB toolbox that could be used >>> for complex images. There are some good toolboxes available however they >>> can only work for real images. > >> I know what complex numbers are, but what is a complex image? >> Can it be reproduced by printing? > > I don't know about complex, but there are some cases in optics > where phase information is important. If you represent amplitude > and phase as a complex number then that would count. > > Holography, in some sense, stores both the amplitude and phase > of the reflected beam, and holograms are difficult to reproduce > by intensity based reproduction systems.
I used to make monochrome holograms using high-resolution black-and-white photographic plates. Those holograms recorded depth. On the other hand. Lippmann photographs used phase (in a way) to record color with the same monochromatic emulsion. I don't know of a process that does both in one image. Jerry -- It matters little to a goat whether it be dedicated to God or consigned to Azazel. The critical turning was having been chosen to participate. &#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;
On 3/5/2010 12:35 PM, Jerry Avins wrote:
> glen herrmannsfeldt wrote: >> Jerry Avins <jya@ieee.org> wrote: >>> Sylvia wrote: >>>> I am searching for a robust wavelet based MATLAB toolbox that could >>>> be used >>>> for complex images. There are some good toolboxes available however >>>> they >>>> can only work for real images. >> >>> I know what complex numbers are, but what is a complex image? Can it >>> be reproduced by printing? >> >> I don't know about complex, but there are some cases in optics >> where phase information is important. If you represent amplitude >> and phase as a complex number then that would count. >> >> Holography, in some sense, stores both the amplitude and phase >> of the reflected beam, and holograms are difficult to reproduce >> by intensity based reproduction systems. > > I used to make monochrome holograms using high-resolution > black-and-white photographic plates. Those holograms recorded depth. On > the other hand. Lippmann photographs used phase (in a way) to record > color with the same monochromatic emulsion. I don't know of a process > that does both in one image. > > Jerry
Some image sources (e.g., radar) have underlying data that is complex-valued, and the image is generated, typically, by detecting the magnitude of the data, sometimes with an emphasis, log, or other detection map. Maybe a "complex image" is the underlying data before detection? -- Eric Jacobsen Minister of Algorithms Abineau Communications http://www.abineau.com
Eric Jacobsen wrote:
> On 3/5/2010 12:35 PM, Jerry Avins wrote: >> glen herrmannsfeldt wrote: >>> Jerry Avins <jya@ieee.org> wrote: >>>> Sylvia wrote: >>>>> I am searching for a robust wavelet based MATLAB toolbox that could >>>>> be used >>>>> for complex images. There are some good toolboxes available however >>>>> they >>>>> can only work for real images. >>> >>>> I know what complex numbers are, but what is a complex image? Can it >>>> be reproduced by printing? >>> >>> I don't know about complex, but there are some cases in optics >>> where phase information is important. If you represent amplitude >>> and phase as a complex number then that would count. >>> >>> Holography, in some sense, stores both the amplitude and phase >>> of the reflected beam, and holograms are difficult to reproduce >>> by intensity based reproduction systems. >> >> I used to make monochrome holograms using high-resolution >> black-and-white photographic plates. Those holograms recorded depth. On >> the other hand. Lippmann photographs used phase (in a way) to record >> color with the same monochromatic emulsion. I don't know of a process >> that does both in one image. >> >> Jerry > > Some image sources (e.g., radar) have underlying data that is > complex-valued, and the image is generated, typically, by detecting the > magnitude of the data, sometimes with an emphasis, log, or other > detection map. Maybe a "complex image" is the underlying data before > detection?
I wasn't skeptical. Finding new ideas to explore is a big part of the pleasure I get from hanging out here. Jerry -- It matters little to a goat whether it be dedicated to God or consigned to Azazel. The critical turning was having been chosen to participate. &#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;&#2013266095;