User Manual v.2
QVidium
®
QVENC4K™ UHD/HEVC Video Encoder
Copyright 2023 QVidium
®
Technologies, Inc.
Page 35 of 43
7
Appendices
7.1 Appendix A: Encoder Configuration Parameters
This section explains the parameters related to the analog input signals and encoding settings and
how they relate to the operation of the encoder and error correction and network transport setup.
Video Encoding Bit Rate:
Total peak stream bit rate for Variable Bit Rate (VBR) video encoding.
The resulting transport stream bit rate is the sum of the bit rates of the video program, audio
program and program stream information. The video bit rate is specified in bits per second and can
range from 128 Kbps for CIF resolution to 19 Mbps for 720x480 (NTSC) or 720x576 (PAL)
standard definition resolutions, or can range from 4 Mbps to 19 Mbps for high definition video
resolutions. The higher the bit rate, the better the video quality.
Audio Bit Rate (compressed):
The audio bit rate determines encoding audio quality and allows
you to trade off audio throughput for quality. The audio bit rate can be set to one of 64,000,
128,000, 192,000, 256,000 or 384,000 bits per second. Increasing the audio bitrate, up to a
maximum value of 384 Kbps increases the audio fidelity. Regardless of the audio signal level on
either channel, selecting an audio bitrate of 64 Kbps or higher will always force the encoder to
send 2 channels of audio (stereo audio). Each audio channel uses one-half of the selected audio
bitrate. The H.264 HD Video Encoder
™ encodes audio using either MPEG-1 Layer II encoding,
MPEG2 AAC, or MPEG4 AAC audio encoding.
For minimizing the audio bitrate, we provide the option of setting the number of audio channels to 1
and the audio bitrate to 16 Kbps or 32 Kbps. Do not use an audio bitrate less than 64 Kbps unless
you set the number of audio channels to 1. Even then, setting the number of audio channels to 1
has the potential to cause unexpected halting of the encoder. So, please be aware that this option
may impact the reliability of the encoder.
Audio Sampling Rate (Hz):
The audio sampling rate specifies the clock rate for capturing and
digitizing the incoming analog audio signal. Because of anti-aliasing filtering, the maximum audio
frequency that can be digitized is limited to a frequency of about 1/3 to 1/2 of the audio sampling
rate. Internal anti-aliasing filters severely attenuate audio signals above a frequency of about 1/3 of
the sampling rate. Thus, for a standard music CD rate of 44.1 KHz, the maximum audio frequency
that the encoder can pass is about 14.7 KHz.
SDI formatting requires that the audio sampling rate be fixed at 48 KHz, so the current user
interface disables setting this value.
Network Parameters
The fields below relate to Ethernet/IP video transport settings.
IP Transport:
This selects the type of video IP packet encapsulation and error correction used by
the encoder in generating a Video/IP stream. All packetized video transport mechanisms
encapsulate a multiplexed variable bit rate MPEG-2 transport stream.
ARQ uses QVidium’s patented error correction mechanism based on a time-constrained
selective packet retransmission algorithm, in place of FEC. It also encapsulates the video