1. A computer-implemented method of determining that a video contains inappropriate content, the method comprising: identifying a set of time-series features associated with a video; generating a scale space decomposition from the set of time-series features, the scale space decomposition being associated with a plurality of scales and comprising a plurality of space components corresponding to the scales; determining a set of multi-scale features associated with the video based on the scales in the generated scale space decomposition, wherein each of a plurality of the multi-scale features is associated with a scale of the plurality of the scales, with one or more of the space components corresponding to the scale, and with a spatial or temporal portion of the video corresponding to a threshold of the time-series features at the scale, and wherein at least some of the multi-scale features are associated with a spatial or temporal portion of the video containing inappropriate content; and determining that the video contains inappropriate content based on the set of multi-scale features.