Extron Electronics MS9400 HD FrEND - Manual (Page 58)

MS9400 HD FrEND User Guide Appendix D: Specifications
58 Rev. 1.54
Appendix C:
Encoding Guidelines
The following notes present encoding details required for the MS9400 High Definition Video Player.
• MPEG files must be encoded as a Transport Stream.
• Elementary Video stream must be Main Profile High Level
MP@HL 4:2:0.
• Elementary Audio Stream must be AC3 encoded.
• Transport stream packet size is 188bytes. This is the standard size, although some encoders generate
packets of 204 bytes. The extra data contains error detection information, used for satellite transmission.
• Stream must start with an I frame and finish on a 188 bytes packet boundary.
• The two most popular resolutions supported are 1920 x 1080 x 59.94 interlace and 1280 x 720 x 59.94
progressive.
• Recommended Video PID numbers are 17, 33 & 49. Audio PID numbers are video PID + 3. Try to ensure
that all files are encoded with the same PID. MediaSonic normally use 49.
• The standard ATSC bit rate is 19.39Mb/s. Higher bit rates up to 30Mb/s can be accommodated.25Mb/s is
an excellent compromise between image quality and file size (storage).
• It is preferable to use closed Group of Pictures (GOPs) if this option is available with the encoder. The
preferred, though not required, GOP size is 15 frames. This provides a good compromise between
compression and random access in the stream.
• A GOP pattern containing I, B & P frames will provide the most efficient compression.
I B B P B B P… generally produces good results.
• Each GOP should contain a sequence header.