The generated set of points in a data space 175 for each category or sub-category of live event (e.g., sports events, football games, soccer games, scheduled newscasts, concerts, breaking news events, etc.) are pruned and used as inputs to an optimization function to determine adaptive live encoding ladders 170, where each adaptive live encoding ladder 170 is associated with a particular type or category of live event. For example and in the context of a single adaptive live encoding ladder 170, points that correspond to quality values below a threshold are pruned. Similarly, points that correspond to encoding runtimes that exceed a threshold are pruned. Excessive encoding runtimes may be particularly troublesome for streaming of live content, and thus the limits on encoding runtimes may be lower than corresponding encoding runtime limits for recorded content. A performance boundary curve is generated based on the pruned points in data space 175. An optimization function is then applied to the pruned points in data space 175 to satisfy a constraint function relative to the performance boundary curve. For example, a predetermined number of points, such as four, are selected from the pruned points in order to maximize the volume covered in data space 175 under the performance boundary curve. Each of these four points corresponds to a particular encoding profile, and the set of four points identify the encoding profiles to include in a particular adaptive encoding ladder 170 (e.g., a ladder 170 configured for a particular type of live event). The disclosed technique for determining adaptive encoding ladders 170 allows for live stream encoding ladders that are each tailored to the characteristics of their respective live event types, based on sampled formerly-live content from media content 105. The adaptive encoding ladders 170 provide better compression and/or better video quality for the particular characteristics of the video presentations in media content 105, than would otherwise result from the use of a generic encoding ladder such as encoding ladder 110.