Digital Video Recorder (DVR) Tips

Tag: MPEG Audio DVR

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Digital Video Recorder (DVR) Tips

1. Q: The purpose and classification of the DVR.

A: The main purpose of the DVR is to convert the analog signal transmitted from the front-end device (such as a camera) into a digital signal, which is compressed and stored in the hard disk, generally divided into PC type and

Embedded.

2. Q: What is MPEG?

A: It is an organization jointly established by ISO (International Standardization Association) and IEC (International Electron Association) in 1988. Its main work is devoted to moving images (MPEG video) and its companion

Standardization of audio coding (MPEG audio).

3. Q: What kinds of MPEG series are available?

A: MPEG has a total of five versions: MPEG-1, MPEG-2, MPEG-4, MPEG-7 and MPEG-21. Among them, MPEG-1 and MPEG-2 are widely used, and MPEG-4 has been launched for two years.

But its application has only recently become active. MPGE-7 and MPEG-21 are future standards.

4. Q: What are the applications of MPEG-1?

A: MPEG-1 was established in 1992. It is an international standard for digital storage media moving images and audio code design for data transmission rates below 1.5 Mbps. It is mainly used on CD-ROM (including

Vdieo-CD, CD-I, etc.) store color synchronized motion video images. The purpose is to compress the 221 Mbit/s N image to 1.2 Mbit/s with a compression ratio of 200:1. Using MPEG-1 compression calculation

The method can compress a 120-minute movie to about 1.2 GB, so VCD production is widely used. Currently, more than 90% of VCDs are compressed in MPEG-1 format.

5. Q: What are the applications of MPEG-2?

A: MPEG-2 was introduced in 1996 and is mainly used to solve multimedia transmission problems. The quality of images transmitted over broadband can reach the standards of TV broadcasting and even HDTV, supporting a wider resolution.

And the bit rate range becomes the compression method for digital image disc (DVD) and digital broadcast TV. It can compress a 120-minute movie to 4-8GB, providing bass channels and up to 7

Sound channel.

6. Q: Why is the MPEG-3 standard not formulated?

A: Since the excellent performance of MPEG-2 can be applied to HDTV, the MPEG-3 standard has not been developed. What we usually call MP3 refers to MPEG Layer3, just an audio compression of MPEG.

standard.

7. Q: What are the applications of MPEG-4?

A: MPEG-4 was released in January 1999, followed by the second edition in December. The official ISO of MPEG-4 is named ISO/IEC14496. The biggest innovation of MPEG-4 is to give users the right response.

Use the ability to build systems, not just the user-oriented fixed standards. MPEG-4 will integrate as many data types as possible, making it possible for us to build a personalized audiovisual system for the first time.

System.

8. Q: Where is the advantage of MPEG-4 compared with MPEG-1 and MPEG-2?

A: Compared with MPEG-1 and MPEG-2, it not only has advantages in compression algorithms and disk space applications, but also becomes more mature in technology over time. If you bring a group

Children go to the toy store. In the world of MPEG-1 and MPEG-2, you can only tell them: "Put your nose on the window and watch the toys." But in the world of MPEG-4, you can tell them

"Do you see the toy? Go play with him!"

9. Q: What is the latest MPEG digital compression format?

A: The MPEG organization is about to approve a new digital compression format called H.264, created by the United Video Group, a joint video group formed by the United States and the European Standards Organization. It will be used as MPEG-4.

Part 10 of the standard was adopted at the end of this year. It speeds up the development of Internet and wireless video on demand services, and improves performance by 33% over MPEG-4 video formats.

10. Q: What is the H.261 and H.263 standards?

A: In 1984, the International Telegraph and Telephone Consultative Committee (CCITT) Study Group 15 established an expert group to study the coding standards for video telephony and conference television, and in 1990

The officially adopted the CDELC H.261 standard for audiovisual service codec with transmission rate of P×64kb/S (P=1, 2...30). This standard is mainly for meeting through the telephone line, visible

Depending on the phone and other multimedia communications.

The H.263 video coding standard is one of the very low code rate coding standards published in 1996. It is the video coding part of the H.324 series of recommendations.

11. Q: What are the main technical parameters of D-TEG-1 and D-TEG-Poswatch DVR represented by our company?

A: D-TEG-1 adopts MPEG1, MPEG2 optional video compression mode, PAL resolution is 768×576, operating system is RTOS; D-TEG-Poswatch video compression format is H.263,

The resolution is 640×480, and the operating system is also RTOS.

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