Forward error correction (FEC) panel

3a

3b

3c

Figure 28. Audio Encoder FEC Panel

NOTES: FEC is only applied to the audio data channel; it is not applied to the video channel.

FEC is effective only for RTP transports. It should not be used for TCP

transport.

FEC is not required, and is not applied when the encoder is configured in

stereo mode.

Forward error correction can be applied to the audio data in data streams that use the RTP transport to protect audio data against data loss. Forward error correction enables the decoder to recreate data that has been lost or corrupted without retransmission. FEC adds additional data to the stream that the decoder can use to detect and reconstruct any lost packets. The FEC data is sent separately from the image and audio data.

The level of FEC can be set to protect against different levels of data loss. This produces a corresponding change in the amount of data that is transported and thus, the bit rate is increased or decreased in proportion to the amount of FEC applied.

The VN-Matrix 325 products implement the recommendations defined by the PRo-MPEG Code of Practice #3 (CoP3)/SMPTE 2022 standard.

ÑFEC Mode — The FEC can be applied as either column only or row and column.

Row FEC protects against the loss of a single packet. It is the simplest method of protection and results in the lowest overhead in

terms of bit rate and latency. However, it cannot handle consecutive packet losses

(burst packet loss).

Column FEC protects against burst packet loss, providing that the burst of packet losses are not in the same row. Since correction data is only calculated on one dimension, column FEC is known as 1-dimensional (1-D) FEC.

By using both FEC methods together, 2-dimensional (2-D) FEC, the combined effect protects against more loss combinations than either scheme by itself.

P1

P2

P3

P4

FR1

P5

P6

P7

P8

FR2

P9

P10

P11

P12

FR3

P13

P14

P15

P16

FR4

P17

P18

P19

P20

FR5

FC1

FC2

FC3

FC4

 

The chart at left shows the FEC scheme applied to a 4 column x 5 row structure. This scheme adds 5 row FEC packets (FR1 through FR5) and 4 column FEC (FC1 through FC4) packets to every 20 data packets. This scheme can protect for burst packet losses up 5 packets long.

VN-Matrix 325 Serial Digital Over IP CODEC • Operation 40

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Extron electronic 325 manual Forward error correction FEC panel, Audio Encoder FEC Panel

325 specifications

Extron Electronics has established itself as a key player in the AV technology industry, providing innovative solutions for a wide range of applications. Among their product lineup, the Extron Electronics 225 and 325 series of devices stand out for their advanced features, technologies, and characteristics that cater to both commercial and educational environments.

The Extron 225 and 325 series are designed for seamless integration into various AV systems, offering unparalleled performance and reliability. At the core of these devices is their robust signal processing capability. Both models are equipped with high-performance scalers and switchers that ensure optimal video quality. They support a wide range of resolutions, including 4K, enabling users to connect various sources without compromising image fidelity.

One of the key features of the 225 and 325 series is their versatile connectivity options. These devices come with multiple inputs, including HDMI, VGA, and composite, allowing for the integration of various AV sources. The series also includes configurable outputs, which can be customized according to the specific requirements of the installation. This flexibility is vital in multipurpose spaces where different AV setups are needed.

The technologies embedded in the 225 and 325 series also enhance usability and control. They feature Extron’s integrated control systems, which simplify the operation of entire AV systems. Users benefit from the intuitive user interface, enabling easy switching and management of devices. Additionally, compatibility with third-party control systems allows for seamless integration into existing setups, streamlining operations.

Another noteworthy characteristic is the series’ built-in audio processing capabilities. Both the 225 and 325 models support various audio formats, ensuring high-quality sound output. They also include audio embedding and de-embedding functions, facilitating the integration of audio sources with video signals.

Reliability and durability are hallmarks of the Extron brand, and the 225 and 325 series are no exceptions. Designed for long-term use, these devices undergo rigorous testing to ensure they perform consistently under demanding conditions. Their compact form factor also allows for easy installation in constrained spaces, making them ideal for a variety of environments.

In summary, the Extron Electronics 225 and 325 series deliver top-tier performance, expansive connectivity, and exceptional audio-visual processing capabilities. Their innovative features and robust design make them valuable additions to any AV installation, catering to a wide range of user needs in commercial and educational settings. With Extron’s commitment to quality and user-friendly solutions, the 225 and 325 series stand as testament to their leadership in the AV technology realm.