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The diffuse morphology and transient nature of coronal mass ejections (CMEs)make them difficult to identify and track using traditional image processingtechniques. We apply multiscale methods to enhance the visibility of the faintCME front. This enables an ellipse characterisation to objectively study thechanging morphology and kinematics of a sample of events imaged by the LargeAngle Spectrometric Coronagraph (LASCO) onboard the Solar and HeliosphericObservatory (SOHO) and the Sun Earth Connection Coronal and HeliosphericInvestigation (SECCHI) onboard the Solar Terrestrial Relations Observatory(STEREO). The accuracy of these methods allows us to test the CMEs fornon-constant acceleration and expansion.  We exploit the multiscale nature of CMEs to extract structure with amultiscale decomposition, akin to a Canny edge detector. Spatio-temporalfiltering highlights the CME front as it propagates in time. We apply anellipse parameterisation of the front to extract the kinematics (height,velocity, acceleration) and changing morphology (width, orientation).  The kinematic evolution of the CMEs discussed in this paper have been shownto differ from existing catalogues. These catalogues are based uponrunning-difference techniques that can lead to over-estimating CME heights. Ourresulting kinematic curves are not well-fitted with the constant accelerationmodel. It is shown that some events have high acceleration below $\sim$5R$_{\sun}$. Furthermore, we find that the CME angular widths measured by thesecatalogues are over-estimated, and indeed for some events our analysis showsnon-constant CME expansion across the plane-of-sky.

The kinematics of coronal mass ejections using multiscale methods