<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><font class="Apple-style-span" face="Times"><br></font></div><div>Video tracking is tricky, but the basics are not too hard. In the Pd-extended Help Browser, check out these patches:</div><div><br></div><div>manuals -> 2.Image -> 17.tracking.pd</div><div>examples -> Gem -> 04.video -> 03.movement_detection.pd</div><div><br></div><div>I am guessing the first is the one you want, its based on background subtractions, which is a widely used technique.</div><div><br></div><div>.hc</div><br><div><div>On Mar 16, 2009, at 12:53 PM, Simon Ball wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">Hi there<br><br>I'm having trouble realising an idea. I've got the software running (mac book pro) and managed to play with some of the examples, however I am new to PD, so bare with me!<br><br>I'm trying to generate a composition of images that float in 3D space. I want the images or layers to move and rotate towards areas of a screen where movement is detected. I don't need to track specific points of motion, simply to judge where movement is taking place. I think this will involve reading frames and analysing changes in pixels. Does that make sense?<br> <br>I plan to use a mini DV camera to run this, on a high contrast background, although I've seen a similar method of recording movement with a webcam and processing, which worked pretty well. (<a href="http://vimeo.com/1948430?pg=embed&sec=">http://vimeo.com/1948430?pg=embed&sec=</a> - tracks changes in pixels, although I'm not sure how).<br> <br>I assume that this will involve some sort of trigonometry to move images towards points where motion is detected, although I'm not sure how to apply this in PD. Also, how to I generate a floating effect, much like 'easing' does in animation software. And can this work with 3D, mapped images in PD?<br> <br>I hope thats clear, if a little broad, let me know you need any further info.<br><br>Thanks in advance for any suggestions/solutions.<br><br>Simon<br><br>Simon Ball<br> _______________________________________________<br><a href="mailto:Pd-list@iem.at">Pd-list@iem.at</a> mailing list<br>UNSUBSCRIBE and account-management -> <a href="http://lists.puredata.info/listinfo/pd-list">http://lists.puredata.info/listinfo/pd-list</a><br></blockquote></div><br><div> <span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><br class="Apple-interchange-newline"><div><br class="khtml-block-placeholder"></div><div><br></div><div>----------------------------------------------------------------------------<br></div><div><br class="khtml-block-placeholder"></div><div>All mankind is of one author, and is one volume; when one man dies, one chapter is not torn out of the book, but translated into a better language; and every chapter must be so translated.... -John Donne </div><br class="Apple-interchange-newline"></div></span> </div><br></body></html>