1. In a digital medium environment to enhance picture vectorization by facilitating conversion of raster images to vector images based on spatially-localized user control, a method implemented by a computing device, the method comprising: displaying, by the computing device, a raster image corresponding to a picture having multiple semantic elements, the raster image including multiple image features; segmenting, by a segmentation module of the computing device, the raster image into multiple segments, each segment of the multiple segments based on at least one image feature of the multiple image features, the multiple image features serving as a proxy for the multiple semantic elements of the picture; presenting, by a localized user control module of the computing device, a user interface feature to provide localized control of a vectorization of the picture, the localized control pertaining to a portion of the raster image; detecting, by the localized user control module of the computing device, a user control signal indicative of the portion of the raster image for which a localized vectorization characteristic is to be adjusted; producing, by a vector image production module of the computing device, a vector image corresponding to at least part of the picture based on the multiple segments and an adjusted localized vectorization characteristic; and displaying, by the computing device, the vector image.