Autodesk 64006-051108-9001 User Guide - Page 198

190 Chapter 8: Encoding Encoding Speed (MPEG-1, MPEG-2 only) This pop-up controls the trade-off between faster encoding operations and the best video quality. •Standard - With most material, you should get excellent results with this setting. •Slower (higher quality) - Produces the best possible results, but takes longer to encode. •Faster (lower quality) - Encodes the fastest of all the options, but you may sacrifice overall quality. This is best used if time is a bigger consideration than quality. Frames or Fields (MPEG-2 only) Select the scan mode for the source media field dominance. • Frames (progressive) • Fields (interlaced) Video Buffer Verifier (MPEG-1, MPEG-2 only) Video Buffer Verifier is a MPEG standard that helps ensure that the incoming video data stream never exceeds the buffer on the MPEG decoder. The value of this setting is in buffer units, which are 2 KB each. It should not be necessary to change this setting. Group of Pictures (GOP) (MPEG-1, MPEG-2 only) Use the frames field to set the size of the GOP, and the P-Frame distance pop-up to select the pattern for the GOP. New GOP on Scene Change (MPEG-1, MPEG-2 only) Select to create a new GOP at each change of scene. Open GOPs (MPEG-1, MPEG-2 only) Select to create open GOPs, clear to create closed GOPs. An open GOP takes information from adjacent GOPs to improve quality and is best for MPEG-1 streams, but makes random access harder. A closed GOP only uses information from the frames within that GOP. Using closed GOPs may produce lower-quality streams at the same bitrate, but the difference may not be discernible at higher bitrates. Closed GOPs are needed if the stream is to be edited. Some authoring programs require closed GOPs.