Hi..All, I have started to work on Image processing. I have used Cross- correlation to find the match between two images. Now, I want to remove barrel distortion from the sample image. But I don't know the algorithm to remove barrel distortion. Does any one have any idea of the same ? Thanks in advance..
Barrel Distortion correction algorithm
Started by ●August 27, 2007
Reply by ●August 27, 20072007-08-27
On Aug 26, 11:29 pm, chauhan.pandur...@gmail.com wrote:> Hi..All, > > I have started to work on Image processing. I have used Cross- > correlation to find the match between two images. Now, I want to > remove barrel distortion from the sample image. But I don't know the > algorithm to remove barrel distortion. > > Does any one have any idea of the same ? > > Thanks in advance..Google is your friend. Try: barrel distortion correction and skip over the responses about software products to get: http://mi3.shef.ac.uk/publications/DistCorrImage_G1.pdf and more. Or try: measuring barrel distortion to get: http://scien.stanford.edu/class/psych221/projects/06/ddpatil/ee362ProjectReport.pdf and more. Dale B. Dalrymple http://dbdimages.com
Reply by ●August 27, 20072007-08-27
On Aug 27, 12:30 pm, dbd <d...@ieee.org> wrote:> On Aug 26, 11:29 pm, chauhan.pandur...@gmail.com wrote: > > > Hi..All, > > > I have started to work on Image processing. I have used Cross- > > correlation to find the match between two images. Now, I want to > > remove barrel distortion from the sample image. But I don't know the > > algorithm to remove barrel distortion. > > > Does any one have any idea of the same ? > > > Thanks in advance.. > > Google is your friend. > > Try: barrel distortion correction > and skip over the responses about software products to get:http://mi3.shef.ac.uk/publications/DistCorrImage_G1.pdf > and more. > > Or try: measuring barrel distortion > to get:http://scien.stanford.edu/class/psych221/projects/06/ddpatil/ee362Pro... > and more. > > Dale B. Dalrymplehttp://dbdimages.comHi...Dale, Thanks for your link.
Reply by ●August 27, 20072007-08-27
On Aug 27, 12:30 pm, dbd <d...@ieee.org> wrote:> On Aug 26, 11:29 pm, chauhan.pandur...@gmail.com wrote: > > > Hi..All, > > > I have started to work on Image processing. I have used Cross- > > correlation to find the match between two images. Now, I want to > > remove barrel distortion from the sample image. But I don't know the > > algorithm to remove barrel distortion. > > > Does any one have any idea of the same ? > > > Thanks in advance.. > > Google is your friend. > > Try: barrel distortion correction > and skip over the responses about software products to get:http://mi3.shef.ac.uk/publications/DistCorrImage_G1.pdf > and more. > > Or try: measuring barrel distortion > to get:http://scien.stanford.edu/class/psych221/projects/06/ddpatil/ee362Pro... > and more. > > Dale B. Dalrymplehttp://dbdimages.comI have read the pdf. It is nice. Thanks ...again. Do u have another method that is for Barrel distortion ?
Reply by ●August 27, 20072007-08-27
On Aug 27, 2:29 am, chauhan.pandur...@gmail.com wrote:> Hi..All, > > I have started to work on Image processing. I have used Cross- > correlation to find the match between two images. Now, I want to > remove barrel distortion from the sample image. But I don't know the > algorithm to remove barrel distortion. > > Does any one have any idea of the same ? > > Thanks in advance..Besides, what Dale offered, try googleing for "Panorama Tools" by Dersch. I know he used to offer the source code for free. With his stuff, you could actually apply 3 different corrections (one for each color channel) and pretty well correct chromatic aberation in addition to correcting barrel/pincushion distortion. You will find some ultra wide zooms actually have a moustache distortion. But these are well handled by a radial mapping function. They just take a lot of effort to characterize. Clay
Reply by ●August 28, 20072007-08-28
chauhan.pandurang@gmail.com wrote:> On Aug 27, 12:30 pm, dbd <d...@ieee.org> wrote: >> On Aug 26, 11:29 pm, chauhan.pandur...@gmail.com wrote: >> >>> Hi..All, >>> I have started to work on Image processing. I have used Cross- >>> correlation to find the match between two images. Now, I want to >>> remove barrel distortion from the sample image. But I don't know the >>> algorithm to remove barrel distortion. >>> Does any one have any idea of the same ? >>> Thanks in advance.. >> Google is your friend. >> >> Try: barrel distortion correction >> and skip over the responses about software products to get:http://mi3.shef.ac.uk/publications/DistCorrImage_G1.pdf >> and more. >> >> Or try: measuring barrel distortion >> to get:http://scien.stanford.edu/class/psych221/projects/06/ddpatil/ee362Pro... >> and more. >> >> Dale B. Dalrymplehttp://dbdimages.com > > I have read the pdf. It is nice. > Thanks ...again. > Do u have another method that is for Barrel distortion ?Perhaps my frustration in another thread has shortened my temper. Do you even know what barrel distortion is? It seems to me that if you understood it you would have less difficulty dealing with it, and wouldn't likely have asked for *THE* algorithm to correct it. Instead of making you guess, I'll tell you. Barrel distortion is a decrease of an image's magnification as a function of radial distance from the optical axis. For modest amounts, straight lines bare imaged as parabolas. Correcting it amounts to measuring features that will allow you to deduce magnification function, then applying a geometric transformation to correct it. I don't know about you, but I can code well enough so that hunting for somebody else's "THE algorithm" that might do more or less what I want would probably take me more time than writing it from first principles. Of course, the hard part would be characterizing the distortion, and I'd be glad to learn how somebody managed that, but I'm not sure it's worth an extensive search. A good reference for optics and the algebraic treatment of the five Seidel aberrations is A.E. Conrady, "Applied Optics and optical Design Part One", ISBN 0-486-67007-4, available from Dover. Be a sport and get Part Two also. ISBN 0-486-67008-2, and it's $2 cheaper. Jerry -- Engineering is the art of making what you want from things you can get. ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯
Reply by ●August 29, 20072007-08-29
On Aug 28, 8:10 am, Jerry Avins <j...@ieee.org> wrote:> chauhan.pandur...@gmail.com wrote: > > On Aug 27, 12:30 pm, dbd <d...@ieee.org> wrote: > >> On Aug 26, 11:29 pm, chauhan.pandur...@gmail.com wrote: > > >>> Hi..All, > >>> I have started to work on Image processing. I have used Cross- > >>> correlation to find the match between two images. Now, I want to > >>> remove barrel distortion from the sample image. But I don't know the > >>> algorithm to remove barrel distortion. > >>> Does any one have any idea of the same ? > >>> Thanks in advance.. > >> Google is your friend. > > >> Try: barrel distortion correction > >> and skip over the responses about software products to get:http://mi3.=shef.ac.uk/publications/DistCorrImage_G1.pdf> >> and more. > > >> Or try: measuring barrel distortion > >> to get:http://scien.stanford.edu/class/psych221/projects/06/ddpatil/ee=362Pro...> >> and more. > > >> Dale B. Dalrymplehttp://dbdimages.com > > > I have read the pdf. It is nice. > > Thanks ...again. > > Do u have another method that is for Barrel distortion ? > > Perhaps my frustration in another thread has shortened my temper. Do you > even know what barrel distortion is? It seems to me that if you > understood it you would have less difficulty dealing with it, and > wouldn't likely have asked for *THE* algorithm to correct it. > > Instead of making you guess, I'll tell you. Barrel distortion is a > decrease of an image's magnification as a function of radial distance > from the optical axis. For modest amounts, straight lines bare imaged as > parabolas. Correcting it amounts to measuring features that will allow > you to deduce magnification function, then applying a geometric > transformation to correct it. I don't know about you, but I can code > well enough so that hunting for somebody else's "THE algorithm" that > might do more or less what I want would probably take me more time than > writing it from first principles. Of course, the hard part would be > characterizing the distortion, and I'd be glad to learn how somebody > managed that, but I'm not sure it's worth an extensive search. > > A good reference for optics and the algebraic treatment of the five > Seidel aberrations is A.E. Conrady, "Applied Optics and optical Design > Part One", ISBN 0-486-67007-4, available from Dover. Be a sport and get > Part Two also. ISBN 0-486-67008-2, and it's $2 cheaper. > > Jerry > -- > Engineering is the art of making what you want from things you can get. > =AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF==AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF= =AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF- Hide qu= oted text -> > - Show quoted text -Thanks clay. Thanks to Jerry also. Jerry, I have first read and make clear myself about the Barrel distortion. I know the theory of Barrel distortion. But I don't from where to start to remove / correct the barrel distortion from image using the software. And by algorithm, I mean that I need just guidelines for the final software as I don't know where to start. I don't want the software actually. Will u help me ? ( or anyone else ?) Thanks again.
Reply by ●August 29, 20072007-08-29
On Aug 28, 10:32 pm, chauhan.pandur...@gmail.com wrote:> On Aug 28, 8:10 am, Jerry Avins <j...@ieee.org> wrote: > > > > > chauhan.pandur...@gmail.com wrote: > > > On Aug 27, 12:30 pm, dbd <d...@ieee.org> wrote: > > >> On Aug 26, 11:29 pm, chauhan.pandur...@gmail.com wrote: > > > >>> Hi..All, > > >>> I have started to work on Image processing. I have used Cross- > > >>> correlation to find the match between two images. Now, I want to > > >>> remove barrel distortion from the sample image. But I don't know the > > >>> algorithm to remove barrel distortion. > > >>> Does any one have any idea of the same ? > > >>> Thanks in advance.. > > >> Google is your friend. > > > >> Try: barrel distortion correction > > >> and skip over the responses about software products to get:http://mi=3=2Eshef.ac.uk/publications/DistCorrImage_G1.pdf> > >> and more. > > > >> Or try: measuring barrel distortion > > >> to get:http://scien.stanford.edu/class/psych221/projects/06/ddpatil/=ee362Pro...> > >> and more. > > > >> Dale B. Dalrymplehttp://dbdimages.com > > > > I have read the pdf. It is nice. > > > Thanks ...again. > > > Do u have another method that is for Barrel distortion ? > > > Perhaps my frustration in another thread has shortened my temper. Do you > > even know what barrel distortion is? It seems to me that if you > > understood it you would have less difficulty dealing with it, and > > wouldn't likely have asked for *THE* algorithm to correct it. > > > Instead of making you guess, I'll tell you. Barrel distortion is a > > decrease of an image's magnification as a function of radial distance > > from the optical axis. For modest amounts, straight lines bare imaged as > > parabolas. Correcting it amounts to measuring features that will allow > > you to deduce magnification function, then applying a geometric > > transformation to correct it. I don't know about you, but I can code > > well enough so that hunting for somebody else's "THE algorithm" that > > might do more or less what I want would probably take me more time than > > writing it from first principles. Of course, the hard part would be > > characterizing the distortion, and I'd be glad to learn how somebody > > managed that, but I'm not sure it's worth an extensive search. > > > A good reference for optics and the algebraic treatment of the five > > Seidel aberrations is A.E. Conrady, "Applied Optics and optical Design > > Part One", ISBN 0-486-67007-4, available from Dover. Be a sport and get > > Part Two also. ISBN 0-486-67008-2, and it's $2 cheaper. > > > Jerry > > -- > > Engineering is the art of making what you want from things you can get. > > =AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF==AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF= =AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF=AF- Hide= quoted text -> > > - Show quoted text - > > Thanks clay. > Thanks to Jerry also. Jerry, I have first read and make clear myself > about the Barrel distortion. I know the theory of Barrel distortion. > But I don't from where to start to remove / correct the barrel > distortion from image using the software. > And by algorithm, I mean that I need just guidelines for the final > software as I don't know where to start. I don't want the software > actually. > > Will u help me ? ( or anyone else ?) > Thanks again.Perhaps I've been too subtle. My original point was to give you a couple of example searches that could give you a lot of responses. I merely gave two examples of searches and a single, perhaps relevant result from each. Only you can decide if any search result is really useful to you. Each search also yields many more results if you take the time to look at them. And if you want something a little different, modify the search terms and try again. Don't expect useful results to fall only on the first page of Google results. If you can use comp.dsp you ought to be capable of using Google. Dale B. Dalrymple http://dbdimages.com
