Sun Microsystems 2.1 manual Splice Points, Packet Boundary

■All trick files must be encoded at a bit rate that is less than or equal to the bit rate of the normal-speed bit stream.

The Media Stream Manager supports the playing of trick play streams. See the chapter on the Media Stream Manager Client API in the Sun MediaCenter Server Programmer’s Guide for a discussion of how to play titles that have trick play streams.

2.3Splice Points

To facilitate switching among multiple bit streams within a content package, all bit streams must define convenient splice points. A splice point is a position in the bit stream at which the server switches into or out of when a user switches from one speed or direction to another. For optimum switching among streams, you should specify splice point locations in an index file, the format for which is described in Section B.5 “Index File Requirements” on page B-10.

Note –The Media Stream Manager switches among trick play streams and a normal play stream even in the absence of an index file. However, if an index file is not present, the Media Stream Manager performs positioning between streams by the linear interpolation of bit rate over file size, which means that streams are entered and exited at arbitrary points. This sort of stream switching causes problems for some decoders. You should use trick play without an index file only if your decoder is capable of resynchronizing and if artifacts are acceptable.

The frequency of the splice points within the bit streams in a content package should reflect the latency you want for trick play functionality. More splice points mean lower latency.

A splice point must have the characteristics described in the following subsections.

2.3.1Packet Boundary

A splice point must occur on the boundary of the underlying packet. For example, for the MPEGTS format, the splice point should occur on the MPEG-2 transport packet boundary.

Chapter 2 Preparing and Loading Content 2-3