Source address:/player.php/sid/580732/v.swf.

Common video formats

Video format:

Wild mumps virus

alfalfa mosaic virus

Digital audio tape)?DOS file name data file

avi

glitter

3gp

Aniline gentian violet

mp4

space

asf

Shock wave flash

In order to have a general understanding of various common video formats, summarize this thing. Common video formats are divided into video format and streaming video format. Next, let's introduce in detail who are in these two camps:

Image form

MPEG format

This format is a big one in the video camp, and it is also the most common video format we usually see. There are many derived formats, including video files with suffixes of mpg, mpe, mpa, m 15, m 1v, mp2, etc. , all from this family. MPEG format includes three parts: MPEG video, MPEG audio and MPEG system (video and audio synchronization). MP3(MPEG-3) audio file is a typical application of MPEG audio. Video includes MPEG- 1, MPEG-2 and MPEG-4.

MPEG- 1 is widely used to make VCDs and download some video clips, among which VCDs are the most-almost all VCDs are compressed in Mpge- 1 format (the file is *. Dat format). The compression algorithm of MPEG- 1 can compress a movie (original video file) with the length of 120 minutes to the size of 1.2 GB.

MPEG-2 is suitable for DVD production (the file format is *. Vob format), as well as some HDTV high-definition TV broadcasts) and some demanding video editing processing. Using the compression algorithm of MPEG-2, the size of a 120-minute movie (original video file) is about 4GB to 8GB. Of course, its picture quality index is incomparable with MPEG- 1.

MPEG-4 is a new compression algorithm. The ASF format file (which will be introduced next) using this algorithm can make a movie (original video file) with a length of 120 minutes "slim down" to about 300MB. Because it is small and easy to spread, it has become one of the main ways to watch online. This algorithm is said to be a coding technology prohibited from export in the United States. In addition, the source file can be compressed to about 600MB by using DivX format, but its image quality is much higher than ASF. Because of its high efficiency, there are rumors that the US government prohibits the export of this technology.

By the way, I also want to introduce the DivX format. The most incisive word to summarize DivX format is: DVD killer. DivX video coding technology can be said to be born for DVD and developed to break the shackles of ASF. As mentioned above, it uses MPEG-4 algorithm, so only two VCDs are needed to compress a DVD! This not only means that you can get almost the same video quality without buying DVD-ROM, but also has low requirements for the machine to play this code: as long as the CPU is above 300 MHz, 64MB of memory and 4MB of graphics card (I believe most machines meet the requirements now), it can play smoothly.

In addition, it is worth mentioning that MPEG- 1 and MPEG-2 have their own special resolution standards when they are made into VCD and DVD respectively. The resolution of MPEG- 1 compressed image is 352×240 when using NTSC format, 352×288 when using PAL format, and DVD is used. If you plan to make CDs for DVD/VCD players, you need to pay special attention to the formats used by various video recorders when making video files.

Timetable:

Format //2 hour standard quality image

MPEG- 1// 1.2GB

MPEG-2//4-8GB

MPEG-4//300MB

MPEG-4+DivX//600MB

AVI format

AVI is not as complicated as MPEG, and it has existed since WIN3. 1. Its most direct advantages are good compatibility, convenient call and good picture quality, so it is often said to DVD. But its disadvantage is also obvious: large volume. It is precisely because of this that we have seen the birth of MPEG- 1 and MPEG-4. The AVI file size of a 2-hour image is almost the same as that of MPEG-2, but this is only for the standard resolution: the resolution of AVI can be adjusted at will according to different application requirements. The larger the window, the larger the data volume of the file. Reducing the resolution can greatly reduce its size, but the image quality is inevitably damaged. When the file size is similar to MPEG-2 format, the video quality of AVI format is relatively poor, but the requirements for computer configuration are not high. People usually record videos in AVI format first, and then convert them into other formats.

Stream format

RM format

This is the great contribution of Real Company to the multimedia world and the promotion of online movies. Its birth also makes streaming files known to more people. This kind of file can be played in real time, that is, some video files are downloaded from the server to form a video stream buffer and then played in real time, and at the same time, the download is continued to prepare for the next play. This way of "broadcasting while transmitting" avoids the disadvantage that users have to wait for the whole file to be downloaded from the Internet before they can watch it, so it is especially suitable for watching movies online. RM is mainly used for real-time transmission of compressed video on low-speed networks, and also has the characteristics of small size and clarity. The size of RM file depends entirely on the compression ratio chosen when making it, which is why sometimes we see that the image of 1 hour is only 200MB, while others are 500MB.

ASF and WMV formats

Video files with *. Asf and *. Wmv came into being with the suffix RM, which is also the core of WindowsMedia. Their * * * feature is that they use MPEG-4 compression algorithm, so the compression rate and image quality are very good (just worse than VCD and better than RM format). Like most video formats, the picture quality is inversely proportional to the file size. In other words, the better the image quality, the larger the file; On the contrary, the smaller the file, the worse the image quality. When making ASF files, it is recommended to adopt a resolution of 320×240 and a frame rate of 30 frames per second, which can give consideration to both clarity and file size. At this time, the 2-hour image is about 1gb.

MOV format

Of all the video formats, MOV format is probably the least known. Maybe you have heard of QuickTime, which plays files in MOV format. Today, when PC almost dominates the world, the MOV format transplanted from Apple is naturally excluded. It has the technical characteristics of cross-platform and small storage space requirements. The MOV format file with lossy compression method has a slightly better picture effect than AVI format. So far, it has four versions, of which version 4.0 has the best compression ratio.

Detailed description of common video formats

In the multimedia era, computers have become one of the indispensable elements in family entertainment. With computers, we can not only work, search information and learn the latest news information online, but also use them to listen to music and enjoy movies and TV blockbusters in our spare time. Speaking of audio-visual video, if you are a movie fan and often watch movies on your computer, you should be familiar with common video formats such as AVI, MPEG, mov and RM. Now various video formats have sprung up, but for each video format, corresponding software is needed to play Q. For example, files in MOV format need to be played quickly, while files in RM format need the support of Real Player. Although there are many types of videos supported by players now, they are not perfect after all. We often encounter such an "embarrassing" thing: when we have worked hard to download a blockbuster on the Internet to enjoy it, the player installed in the computer does not support this format, not only anxious! So how to solve this problem?

Introduction to video format:

The so-called "know yourself and know yourself, and you will win every battle!" Only by being familiar with various video formats can we lay a good foundation for the subsequent video format conversion. Let's introduce some common video formats in detail:

1.AVI format

Its full English name is Audio Video Interleaved, that is, audio and video interleaved format. It was introduced by Microsoft in 1992, and is known and familiar with people together with Windows3. 1. The so-called "audio and video interleaving" means that video and audio can be intertwined and played simultaneously. The advantage of this video format is that it has good picture quality and can be used across multiple platforms. But its disadvantage is that it is too big, and what is worse is that the compression standards are not uniform. Therefore, it is often encountered that the high version of Windows media player cannot play the AVI format video encoded and edited earlier, and the low version of Windows media player cannot play the latest AVI format video encoded and edited. In fact, the solution is also very simple, and we will give the solution in the later part of video conversion and video restoration. AVI, short for audio and video interleaving. AVI is a video format released by Microsoft, which has existed in the video field for several years. AVI format is convenient to call and the image quality is good, but the disadvantage is that the file is too large.

2.DV-AVI format

The full English name of DV is Digital Video Format, which is a family digital video format jointly proposed by Sony, Panasonic, JVC and other manufacturers. At present, very popular digital cameras use this format to record video data. It can transmit video data to the computer through the IEEE 1394 port of the computer, and can also record the edited video data from the computer back to the digital camera. So is the file extension of this video format. Avi, so we used to call it DV-AVI format.

*. avi (north of avi)

If you find that the original playback software suddenly can't open the AVI file in this format, then you should consider whether you have met n AVI. N AVI is the abbreviation of the new AVI, which is a new video format developed by an underground organization called Shadow Kingdom. It is a modification of Microsoft ASF compression algorithm (not the imagined AVI), and the video format pursues nothing more than compression rate and image quality, so NAVI improves some shortcomings of the original ASF format in order to pursue this goal, so that NAVI can have a higher frame rate. It can be said that NAVI is an improved ASF format without the characteristics of video streaming.

3.MPEG format

Its full English name is Moving Picture Expert Group, which is the format of moving picture expert group. VCD, SVCD and DVD that we often watch at home are all in this format. MPEG file format is the international standard of moving image compression algorithm, which uses lossy compression to reduce redundant information in moving images. MPEG compression method goes further, that is, most of the same parts of two adjacent images are retained, and the redundant parts in the latter image and the previous image are removed, so as to achieve the purpose of compression. At present, there are three compression standards of MPEG format, namely MPEG- 1, MPEG-2 and MPEG-4. In addition, MPEG-7 and MPEG-2 1 are still in the research and development stage.

MPEG- 1: formulated in 1992, it is an international standard designed for digital storage media moving images and audio coding with data transmission rate below 1.5Mbps, which is also the VCD production format we usually see. The file extensions of this video format include. mpg，。 mlv，。 mpe，。 Mpeg and. Dat file in VCD.

MPEG-2: Based on 1994, the design goal is advanced industrial standard image quality and higher transmission rate. This format is mainly used for DVD/SVCD production (compression), as well as some HDTV (high definition television broadcasting) and some demanding video editing and processing. The file extensions of this video format include. mpg，。 mpe，。 mpeg，。 M2v and. Vob file on DVD.

MPEG-4:MPEG-4 was established by 1998 and is specially designed for playing high-quality video of streaming media. It can compress and transmit data with extremely narrow bandwidth through frame reconstruction technology, and obtain the best image quality with the least data. The most attractive thing about MPEG-4 is that it can save small-capacity video files close to DVD quality. The file extensions of this video format include. asf，。 Mov, DivX, AVI, etc.

4.DivX format

This is another video coding (compression) standard derived from MPEG-4, which is what we usually call DVDrip format. It adopts MPEG-4 compression algorithm and integrates MPEG-4 and MP3 technologies. To put it bluntly, it is a video format formed by using DivX compression technology to compress the video image of DVD with high quality, and compressing the audio with MP3 or AC3 at the same time, then synthesizing the video and audio, and adding corresponding plug-in subtitle files. Its picture quality is almost the same as that of DVD, and its volume is only a fraction of that of DVD.

5.MOV format

A video format developed by Apple. The default player is Apple's QuickTimePlayer. It has the characteristics of high compression ratio and perfect video definition, but its biggest feature is cross-platform, that is, it can support not only MacOS but also Windows series. Friends who have used MAC should be exposed to QuickTime. QuickTime was originally Apple's image and video processing software for Mac computers. Quick-Time provides two standard image and digital video formats, that is, it can support static *. PIC and *. JPG image format, dynamic *. MOV based on Indeo compression method and *. MPG video format based on MPEG compression method.

6.ASF format

Its full English name is Advanced Streaming format, which is a video format introduced by Microsoft to compete with the current Real Player. Users can play directly with Windows Media Player that comes with Windows. Because it adopts MPEG-4 compression algorithm, the compression rate and image quality are very good.

Advanced stream format. ASF is a file compression format developed by Microsoft to compete with the current Real player, which can watch video programs directly on the Internet. ASF adopts MPEG4-4 compression algorithm, and the compression rate and image quality are very good. Because ASF exists in a video "streaming" format that can be watched instantly on the Internet, it is not surprising that its picture quality is worse than that of VCD, but it is better than that of RAM format which is also a video "streaming" format.

7.WMV format

Its full English name is Windows Media Video, and it is also a file compression format introduced by Microsoft. It adopts independent coding mode and can directly watch video programs on the Internet in real time. The main advantages of WMV format include: local or network playback, extensible media types, scalable media types, multilingual support, environmental independence, rich inter-stream relationships and scalability. A technical standard for real-time multimedia transmission on the Internet independent of coding mode. Microsoft hopes to use it to replace technical standards such as QuickTime and file extensions such as WAV and AVI. The main advantages of WMV are: extensible media types, local or network playback, extensible media types, streaming priority, multilingual support, scalability and so on.

8.RM format

The audio and video compression standard formulated by network companies is called Real Media. Users can use RealPlayer or RealOne Player to play network audio and video resources that meet the technical specifications of RealMedia, and RealMedia can also set different compression ratios according to different network transmission rates to realize real-time transmission and playback of image data on low-rate networks. Another feature of this format is that users can use RealPlayer or RealOne Player to realize play online without downloading audio and video content.

9.RMVB format

This is a new video format extended from the RM video format upgrade. Its advantage lies in that the RMVB video format breaks the way of average compressed sampling in the original RM format, and makes reasonable use of code rate resources on the basis of ensuring the average compression ratio, that is to say, static scenes with little action can leave more bandwidth space, and when there are fast-moving scenes, these bandwidths will be used. In this way, on the premise of ensuring the quality of still images, the image quality of moving images is greatly improved, thus achieving a delicate balance between image quality and file size.

*.MPEG/。 MPG/。 Data; Digital audio tape

MPEG is also the abbreviation of Moving Picture Experts Group. This format includes MPEG- 1, MPEG-2, MPEG-4 and other video formats. MPEG- 1 is considered to be the most widely used, because it is widely used in the production of VCD and the network application of downloading some video clips. Most VCDs are compressed in MPEG- 1 format (the recording software will automatically convert MPEG- 1 into. DAT format). Using the compression algorithm of MPEG- 1, you can save a 65438. MPEG-2 is used in DVD production, and also widely used in some HDTV (High Definition Television Broadcasting) and some demanding video editing processes. Using the compression algorithm of MPEG-2 to compress a movie with the length of 120 minutes can be compressed to the size of 5-8 GB (the picture quality of MPEG-2 is incomparable to that of MPEG- 1).

*. Random Access Memory/Random Access Memory

*.RM, one of the audio and video compression standards formulated by Real Networks, what Real Player can do is to use Internet resources to broadcast these audio and video that meet the technical specifications of Real Media live. The Real Media specification mainly includes three types of files: RealAudio, Real Video and RealFlash (a new generation of high compression ratio animation format jointly launched by RealNetworks and Macromedia). REAL VIDEO (RA, RAM) format is positioned in the application of video streaming from the beginning, and it can also be said that it is the originator of video streaming technology. You can realize uninterrupted video playback when using a 56K modem to dial up the Internet, but the picture quality is worse than that of VCD. If you have seen those RM-compressed DVDs, you can clearly compare them.