A content delivery server is configured to receive a request for a chunk of a segment of a video stream, the segment of the video stream including a series of chunks, each of the chunks including a set of video frames, a first of the chunks being aligned with a first Instantaneous Decoder Refresh frame in the video stream, and a second of the chunks being aligned with a second subsequent Instantaneous Decoder Refresh frame in the video stream; determine whether the request was received during a first interval or a second subsequent interval of an intra period between the first of the chunks and the second of the chunks; and output the first of the chunks or the second of the chunks for transmission based on the determination of whether the request was received during the first interval or the second interval.