QVidium QVMP2C-1011 - Manual (Page 37)

User’s Manual v.28 QVidium™ MPEG2+4 Codec
37 of 45 - Copyright 2007-2008 QVidium™ Technologies, Inc.
13.2 Appendix B: Decoder Configuration Parameters
This section explains the parameters related to the setup and operation of the MPEG
Decoder, the error correction algorithms, and network transport configuration.
Stream Type: The MPEG2+4 Codec can generate either an MPEG-2 Transport Stream or
an MPEG-2 Program Stream, modified to periodically transmit key video parameters. For
greatest robustness and interoperability with other video networking equipment, we
suggest using the default setting of Transport Stream. However for the lowest possible
stream bit rates, set the Stream Type to Program Stream.
Video Encoding: The MPEG2+4 Codec generates analog composite and S-Video outputs
from a video/IP packet stream encoded using either the MPEG-2 video encoding standard
(MP@ML) or MPEG-4 simple profile ( ISO/IEC 14496-2) compression, as selected.
Video Format: This allows selection between the NTSC standard as used in North
America and Japan and the PAL video format used in Europe for the analog output video
signal. NTSC generates interlaced video at 29.97 frames per second, while PAL generates
interlaced video at 25 frames per second.
Max Stream Bitrate: This parameter allows you to minimize the latency of the video
stream. You should enter an estimate of the maximum anticipated incoming bitrate.
Leaving this blank will default to a value of 4 Mbps. An estimate is less than the actual
stream bitrate may cause occasional pausing or freezing of the video. Too large of an
estimate will add unnecessary additional delay to the video output.
Network Parameters
The fields below relate to Ethernet/IP video transport settings.
IP Transport: This selects the type of video IP packet decapsulation and error correction
expected by the codec in receiving a Video/IP stream. All packetized video transport
mechanisms expect to receive a multiplexed constant bit rate MPEG-2 transport stream to
decapsulate and decode.
• ProMPEG is the default and recovers lost packets from received ProMPEG FEC
checksum packets as per the ProMPEG Forum’s Code of Practice (COP) 3,
Release 2, Annex A and IETF RFC 2733 for IP encapsulation of video and audio
data.
• ARQ uses QVidium’s patent-pending error correction mechanism for lost packet
recovery, in place of FEC. Like ProMPEG transport, it also expects to receive
video as per COP3.2 (without the FEC) and RFC 2733. However it relies upon an
upstream channel on UDP port 7020.
• RTP disables all error correction mechanisms, but still decapsulates the MPEG-2
multiplexed data according to RFC2733.