RTSP
Real Time Streaming Protocol (RTSP) is a network control protocol that is used to control streaming media servers. It provides a means for clients to remotely control the streaming of media from a server, and it allows clients to receive real-time data from the server for the purpose of playback or other processing.
RTSP is typically used to establish and control media sessions between endpoints, such as a client application and a streaming media server. The client sends RTSP requests to the server, such as SETUP, PLAY, and PAUSE, to control the playback of the media. The server sends back RTSP responses to the client, such as 200 OK and 404 Not Found, to indicate the success or failure of the request.
In order for RTSP to work, the client and server must be able to communicate using the RTSP protocol. This typically involves the use of dedicated RTSP ports and the transmission of RTSP messages over a reliable transport protocol, such as TCP or UDP.
ONVIF
ONVIF (Open Network Video Interface Forum) is an industry-wide, open standard for the interoperability of networked video devices, such as IP cameras and video servers. The goal of ONVIF is to enable the integration of different brands and types of network video products, so that they can work together seamlessly and be controlled from a single interface.
ONVIF defines a set of standards and protocols for communication between network video devices, including:
- The transmission of streaming video and audio data over a network
- The discovery and configuration of network video devices
- The control of PTZ (pan-tilt-zoom) cameras
- The storage and retrieval of metadata from network video devices
ONVIF also provides a set of application programming interfaces (APIs) and software development kits (SDKs) that developers can use to integrate ONVIF-compliant devices into their own applications and systems.
POE
Power over Ethernet (PoE) is a technology that allows network devices, such as IP cameras and wireless access points, to be powered by a network cable rather than a separate power cord. This means that a single Ethernet cable can be used to both transmit data and provide electrical power to the device.
PoE uses a technique called “power sourcing equipment” (PSE), where a PoE-enabled device, such as a network switch or router, provides power to the network cable. The device being powered, called the “powered device” (PD), receives the power through the same cable that is used for data transmission.
There are two main types of PoE:
- PoE Type 1 (802.3af): Provides up to 15.4 watts of power
- PoE Type 2 (802.3at): Provides up to 25.5 watts of power
PoE technology is useful because it simplifies the installation and setup of network devices by eliminating the need for separate power cables. This can save time and money, and it can also make it easier to install devices in hard-to-reach or inaccessible locations.
Video Encoding
Video encoding is the process of converting a video file from one format to another. It is a common step in the production and distribution of digital video, and it is used to optimize the video for a specific use case or device.
Video encoding involves a number of steps, including:
- Compressing the video to reduce the file size: This is typically done using a video compression standard, such as H.264 or H.265, which allows the video to be transmitted or stored using less bandwidth and storage space.
- Encoding the video into a specific format: This determines the structure and organization of the video data, and it specifies how the video will be represented in a file or stream. Common video formats include MP4, AVI, and MOV.
- Adding metadata to the video: This includes information about the video, such as its title, author, and creation date, as well as any metadata that is required by the target device or platform.
Video encoding is a complex process that involves a number of technical considerations, such as the bitrate, resolution, and frame rate of the video, as well as the target device or platform. It is typically performed by specialized software or hardware tools, such as encoders or transcoding servers.
H.264
H.264, also known as MPEG-4 Part 10 or AVC (Advanced Video Coding), is a video compression standard that is widely used for the recording, compression, and distribution of high-definition video. It is a popular format for video cameras, video surveillance systems, and video-sharing websites, and it is also used for Blu-ray discs and streaming services, such as Netflix and YouTube.
H.264 is known for its high efficiency and superior quality, as it can compress video files to a smaller size while maintaining a high level of visual fidelity. This allows H.264-encoded video to be transmitted over networks and stored on devices with limited bandwidth and storage capacity.
H.264 is an open standard that is maintained by the International Telecommunications Union (ITU) and the Moving Picture Experts Group (MPEG). It is a flexible and adaptable format, and it can be used for a wide range of applications and devices.
H.265
H.265, also known as High Efficiency Video Coding (HEVC), is a video compression standard that is designed to improve upon the efficiency of its predecessor, H.264/AVC (Advanced Video Coding). It is capable of compressing video files to a smaller size while maintaining a high level of visual quality, and it is widely used for the transmission and storage of high-definition video.
H.265 is an open standard that is maintained by the International Telecommunications Union (ITU) and the Moving Picture Experts Group (MPEG). It is a successor to H.264/AVC, and it offers a number of benefits over the older standard, including:
- Higher efficiency: H.265 can compress video files to a smaller size than H.264, without sacrificing visual quality. This allows for the transmission and storage of high-definition video using less bandwidth and storage space.
- Higher resolution support: H.265 supports higher resolution video than H.264, including up to 8K resolution (7680x4320 pixels) for ultra-high-definition video.
- More advanced coding tools: H.265 includes a number of advanced coding tools, such as parallel processing and improved motion compensation, that can further improve the efficiency of the compression process.
Audio Encoding
Audio encoding is the process of converting an audio signal from one format to another. It is a common step in the production and distribution of digital audio, and it is used to optimize the audio for a specific use case or device.
Audio encoding involves a number of steps, including:
- Compressing the audio to reduce the file size: This is typically done using an audio compression standard, such as MP3 or AAC, which allows the audio to be transmitted or stored using less bandwidth and storage space.
- Encoding the audio into a specific format: This determines the structure and organization of the audio data, and it specifies how the audio will be represented in a file or stream. Common audio formats include WAV, MP3, and AAC.
- Adding metadata to the audio: This includes information about the audio, such as its title, artist, and album, as well as any metadata that is required by the target device or platform.
Audio encoding is a complex process that involves a number of technical considerations, such as the bitrate, sample rate, and channel configuration of the audio, as well as the target device or platform. It is typically performed by specialized software or hardware tools, such as encoders or transcoding servers.
AAC codec
AAC codec is a widely-used and highly-efficient digital audio coding standard that is suitable for a variety of applications and devices. It offers improved sound quality and higher efficiency than MP3, and it is well-suited for the transmission and storage of high-quality audio.
G.711 codec
G.711 is a standard audio codec used for VoIP (Voice over Internet Protocol) communications. It is a Pulse Code Modulation (PCM) codec designed for digital voice transmission over telephone networks. It supports two different audio sample rates: 8 kHz for narrowband and 16 kHz for wideband. G.711 is the most commonly used codec for VoIP, as it provides high-quality audio at low bandwidths.
G.711a
G.711a is a narrowband audio codec that is used for voice over IP (VoIP) applications. It is a version of the ITU G.711 codec, which is the most widely used codec in VoIP. G.711a is an A-law version of the G.711 codec, and it is optimized for use in Europe and other countries where A-law is the preferred pulse code modulation (PCM) format. G.711a is a lossy codec, meaning that some of the audio data is discarded in order to reduce the overall size of the transmission.
G.711μ
G.711μ is a lossy audio codec used for real-time voice communication. It is a standard for compressing voice audio data at rates of 8KHz or 16KHz. It is widely used in VoIP applications for encoding and decoding voice data and is considered one of the most widely used codecs in the world. This codec compresses audio data to reduce its size, which reduces the amount of bandwidth needed to transmit the same amount of audio data. G.711μ is a high-quality codec that offers excellent sound quality with low latency.
Opus codec
Opus is a royalty-free audio codec developed by the Internet Engineering Task Force (IETF) for use in Internet applications such as Voice over IP (VoIP), videoconferencing, in-game chat, and streaming audio. It is designed for both interactive speech and audio streaming applications, and is capable of delivering higher quality audio than most other codecs. Opus is based on the SILK codec, which was developed by Skype, and is supported by all major web browsers.
NVR
A network video recorder (NVR) is a device that is used for the recording, storage, and playback of video from network cameras. It is typically used in surveillance and security systems, and it can be accessed remotely for the purpose of monitoring and reviewing recorded video footage.
An NVR is a specialized computer that is equipped with a hard drive or other storage device for storing recorded video, as well as software for managing the recording and playback of video. It is connected to the network, typically via Ethernet, and it communicates with network cameras to receive and record video streams.
An NVR is typically used in combination with network cameras, which are digital video cameras that are designed to transmit video over a network. The NVR acts as a central hub for the cameras, receiving and storing their video streams, and providing remote access and control capabilities.
Overall, an NVR is a valuable tool for surveillance and security applications, as it allows for the centralized recording and management of video from network cameras.
WebRTC
WebRTC (Web Real-Time Communication) is an open source project that enables web browsers and mobile applications to support real-time communication (RTC) without the need for plugins or additional software. It uses simple APIs to enable peer-to-peer communication and allows developers to embed real-time communication capabilities into their applications. WEBRTC is fast becoming a viable alternative to traditional Voice over IP (VoIP) technology.