The invention concerns a method of broadcasting data files, in particular multimedia files, during a video conference using a sending terminal and a manmachine interface located in the said terminal. The major components of the system comprise a fractionationquench tower and a reaction furnace. A wrinkle component extraction section extracts converted images, obtained by performing nonlinear conversion on each of the band-limited images Tm, as wrinkle components Qm contained in the different frequency bands.