H ELECTRICITY
H04 ELECTRIC COMMUNICATION TECHNIQUE
H04N PICTORIAL COMMUNICATION, e.g. TELEVISION
H04N21/00 Selective content distribution, e.g. interactive television or video on demand [VOD]
H04N21/20 Servers specifically adapted for the distribution of content, e.g. VOD servers; Operations thereof
H04N21/23 Processing of content or additional data; Elementary server operations; Server middleware
H04N21/234 Processing of video elementary streams, e.g. splicing of video streams or manipulating encoded video stream scene graphs
H04N21/23424 involving splicing one content stream with another content stream, e.g. for inserting or substituting an advertisement