QVidium QVSD - Manual (Page 16)

User‟s Manual v.3 QVidium
®
QVSD H.264 SD Video Codec™
Copyright 2011 QVidium
®
Technologies, Inc.Page 16 of 53
Number B Frames: This sets the number of Bi-Directional frames in the GOP. Unless you
need a specific GOP, you should set this to Auto. The GOP can be calculated by the formula:
GOP = (P+1)*(B+1).
Thus, for all I-Frames (GOP=1), you would set P=0 and B=0. For Baseline Profile, the B
parameter is ignored (internally set to 0).
MPEG4 Profile and Level: This sets the H.264 profile and level. Auto uses the best possible
encoding for the given parameters. Use this for backward compatibility with decoders that
cannot handle the more advanced encoding features. If you see jerky video on a decoder and
there is no packet loss and the CPU is not overloaded, then you may want to try lower values
for these settings.
Control Parameters:
Error Handling: Enable this feature when high reliability is required. When set to Reboot or
Restart, this feature starts a supervisory monitoring process that will reboot or restart the
encoder when the encoder halts for any reason. Restarting the encoder is very fast (less than
a second), but may not recover from all types of errors. Restarting can take up to 23 seconds,
but will recover from nearly any error.
Output Parameters:
PMT, Video, Audio, and PCR PID: Changing these values changes the values for the
respective PIDs.
Network Parameters:
TS packets per IP packet: This sets the number of 188-byte MPEG-2 transport stream
packets per UDP/IP output packet payload. The default of 7 sets the payload to 1316 bytes,
which minimizes the IP packetization overhead. A lower value results in a higher output packet
rate.
Use Pacing: Because the video stream is VBR (variable bit rate), an I-Frame (Key Frame)
may generate a large burst of IP packets. Pacing adds output buffering and regulates the
output packet rate to attempt to equalize the output packet rate and reduce burstiness.
Network Bonding and LAN1 Bonding Percent: Network bonding is a special feature
designed for broadband wireless and other network links where a single network link has
insufficient bandwidth for the video and instead you wish to take advantage of both Ethernet
ports on the codec. Setting this parameter to true distributes the video load across both When
the two network links are asymmetric, LAN1 Bonding Percent specifies the relative distribution
of Ethernet packets among the two Ethernet ports. The default, 50 splits the load to 50% on
each Ethernet port.
ARQ Buffers: This controls the amount of memory allocated for storing outgoing packets for
possible later retransmission by the ARQ error correction. The default is 1024, which is
generally enough for normal operation for bitrates under 5 Mbps. This setting allows enough
memory to also run the decoder at the same time for SD video. However, you should increase
this to 4096 when encoding SD video, or when using encoding at bitrates higher than 5 Mbps.
However, you must not start the decoder when running the encoder with this parameter set to
4096.