Showing posts from September, 2012

Adaptive seismic multiple removal with complex wavelet (paper)

The November-December 2012 issue of Geophysics (Volume 77, Issue 6) features (at last) a recent work performed on model-based, adaptive multiple removal in seismic . The concept is illustrated on the figure to the left. Signal obtained from direct reflections of interest (blue) are mixing with other waves bouncing between layers (red). They look alike except for differential attenuation in the frequency domains, different slopes in CMP gathers. Those interested could have a look at the booklet Seismic multiple removal techniques: past, present and future by Eric J. (Dirk) Verschuur . Those more patient may want to waiting for Seismic Multiple Elimination Techniques , by the same author, which should be published in June 2013.As the problem is quite complex per se, hundred of papers have been devoted to multiple elimination techniques, since the January 1948 special issue of Geophysics. A common approach consists in first computing one or several approximate models of the multipl

What is a color?

Typically the kind of image that makes me (still) love image processing. So the "light green" spiraled stripelets have the same absolute color coordinates (yes, R,G,B) as the "light blue" ones. I have checked it with XnView . There is still room for image processing algorithms that meet vision stimuli. The two-penny philosophical question: do these two colors actually merge at the aliased warped end in the center? Indeed, the phenomenon is related to the scale of observation, as one may obseve by zooming in and see how the green and the blue reduce their perceptual distance. Funnily enough, the illusion also works with at least one color blind and image processing specialist colleague (Frédéric Morain-Nicolier @ Pixel Shaker ) who has been kind enough to discuss these issues. So below is the thumbnail and its enlarged version. Of course, you cannot fully trust the present image renderer,. Try by yourself. Akiyoshi Illusion page:

SIVA Conferences : concern fees (update)

Although conferences = concern fees (with the anagram equivalence) for a few organizers, they allow to grab a few call for papers to other conferences. Grabbed from EUSIPCO 2012, along with cfp1 and cfp2 (on time-frequency theory and applications), and after a couple of proofs from a finally painfully published paper in Geophysics , the recent opening of GRETSI 2013 website in Brest, France, provides a good opportunity to release the latest updates on Signal, Image and Volume Analysis (SIVA) Conferences: Eurographics 2013 (Annual conference of the European Association for Computer Graphics) calls for papers on 21/09/2013. CVPR 2015 (IEEE Conference on Computer Vision and Pattern Recognition) is announced in Boston, Massachussetts, USA; ICIP 2016 (IEEE International Conference on Image Processing) in Phoenix, Arizona, USA; ICCV 2015 (International Conference on Computer Vision) in Santiago, Chile.  One of the next target is ICASSP 2013 in Vancouver, Canada, with submi