In this article you will find a summary of the main features of each digital video formats more used today, so you can delve into this fascinating world, and understand a little better what we are doing when playing or converting an video.
While the MP4 format is well known for its features and options, it never hurts to review again the impressive virtues and advantages that provides, besides of the disadvantages, of this popular format.
Belonging to the group Moving Picture Experts Group, MPEG-4 has achieved great popularity among users after Apple includes it in its iTunes software for the distribution of audiovisual content, as it is a container that can hold synchronized audio and video.
The format uses the file extension “.mp4”, it includes an internal audio M4A and M4V video, and can be created from files in AAC, Apple Lossless and MP3, among others.
Note that the container can be identified with other extensions, which are detailed below:
- MP4: Contains audio, video and other advanced services, such as streaming Internet content, can contain video codecs such as MPEG-4, MPEG-2 and MPEG-1, MPEG-4 AAC, MP3, MP2, MPEG-1, MPEG-2, CELP, TwinVQ, SAOL, images with JPEG and PNG extension, subtitle MPEG-4 Timed Text and XMT/bt, and includes support for Systems, which makes it possible to include animation, interactivity and menus similar to DVDs.
- M4A: it Contains only audio.
- M4P: File type Apple FairPlay protected.
- M4V: video only.
- 3GP and 3G2: The extension used in 3G mobile phone technology to store audio and video.
Note that in regard to the type of file whose extension is MP4, is often used as one of the best alternatives to MP3, especially in the most modern devices and Apple products like the iPod and its iTunes store .
This is mainly because the AAC codec is of much better quality that the format MPEG-1 Audio Layer 3 stored in the MP4.
Surely the DivX format was one of the most widespread on the Internet, not just among lovers of audiovisual content, but also a massive scale.
In principle it is important to mention that DivX is, technically speaking, a digital video format, which can be used without problems in almost all current operating systems, so we can not only enjoy DivX video on our PC, but also in various devices, including various models of players.
DivX has achieved resounding success in recent years, and this mainly due to combining digital audio compression in MP3 format, and provides a very good image quality, obviously superior to that offered by the old tape cassettes VHS .
Basically, DivX is a codec that can encode, as its name implies, audiovisual content. Ie that enabling a very high file compression while maintaining the best possible video quality at smaller file size.
With the advent of DVD, and distribution of films and videos in this type of optical medium, DivX became the most chosen option to compress and thereby reduce the size of files and substantially, since usually a whole movie takes up only a total of 700 megabytes in DivX format.
Initially, DivX was developed to be only one format for the transmission of digital television signals, using the MPEG-4 standard. Over the years and diffusion and mass format, it became a true multimedia system that proliferates on the Internet.
However, at the time, the arrival of the Xvid codec put on the background to DivX, since the former can achieve higher image quality, and mainly because it has emerged as an open source project.
Undoubtedly, the AVI format has become in recent years one of the most popular in the world of digital video, and precisely their success is due to good quality offering both image and sound.
Before you start to define what the AVI format is, it is important to mention that his name comes from the acronym for Audio Video Interleave, which was developed by the Microsoft company in the early 90s, in order to provide Windows users a multimedia container that would include audio and video data in a single file.
But also, as expected, this special container allows full synchronization of sound and video images during playback of the file in question.
All this is possible because the AVI format has support for multiple streams of audio and video simultaneously, so the information is stored in this container previously passed through a interleaving process, making it possible for each file fragments extension “.avi” includes information needed to reproduce a series of frames along with the audio that should accompany.
One of the best features of AVI format, is that it allows multiple data streams, this means offering the possibility, for example, to store a movie with multiple sound tracks, ie containing various soundtracks in different languages.
In this sense, when playing a video in AVI format via a media player, will be the program you select which of audio streams including in the container must play with the video, of course according to the preferences of each user. For that, the user must first configure the application.
To play a video with the extension “AVI” will require a video player that can interpret the format, and the corresponding codecs. Usually, in most cases, AVI containers typically include audio in AC3 or MP3, and DivX and Xvid video.
Those who use the Windows operating system know that there is nothing better that play a video with WMV file extension in Windows Media Player, that includes the operating system by default.
This is mainly because the WMV format, short for Windows Media Video, is a group of compression algorithms that belong to the Microsoft Company, which was developed by the company to be an integral part of the framework called Windows Half.
Because of this, it is not surprising that most of the time, an WMV audiovisual file, store inside audio in a format that also belongs to the suite, in this case, Windows Media Audio.
However, it is important to note that when it comes to actually WMV punctually we are referring to the video, the same way that talking about only WMA is sound. Therefore, the WMV video may be within a container and thereby attached to its respective WMA audio. Usually this container is called ASF, that include audio and video. Also they are frequently used in the MPEG-2 and MPEG-4 formats, as they allow the dissemination of material via streaming without major problems.
Although now the WMV file type can be played by a variety of players, beyond own Windows Media Player, the truth is that for many users who often use other operating systems instead of Windows, the display of this file type can become a disadvantage.
Therefore, what we must do to achieve play a video with WMV extension on our PC, it is to have the media player Windows Media Player, if we use the Windows operating system. Otherwise, an excellent alternative is the free and open source VLC player.
However, it should be mentioned that in many cases it may become impossible to play certain WMV videos which were protected with a DRM, i.e. a system of Digital Rights Management, which prevents viewing without payment of use rights.
Popularized on the Internet, the digital video format RealVideo was in his time one of the most used and disseminated within the network to share audiovisual material online.
While the quality of the RealVideo format, we can identify with the extensions “.rv”, “.ram”, “.rm”, “.rmvb” usually not good, the fact is which in recent years has been used by Internet users like a format type of high compression rate to share multimedia material on the network.
In principle, it is important to mention that RealVideo format is property of RealMedia, and together with the audio format RealAudio, has been developed by RealNetworks.
Due to its characteristics, especially the fact that generates files of really small size, RealVideo and RealAudio formats were used much for streaming applications.
Because RealVideo compresses the audiovisual material, certain losses that hurt the quality of content that can ever achieve quality display files that were compressed with other formats, such as MPEG occur.
However, depending on configurations encoding, RealVideo can achieve similar qualities to those achieved with coding performed in MPEG-4 Codec Xvid or DivX, and of course a comparable quality to a Windows Media format Video.
There are four different versions of RealVideo, which have no compatibility between them. The following table versions:
- RV10: RealVideo 5, first version of RealVideo, H.263 format identical
- RV20: RealVideo G2; RealVideo G2 + SVT
- RV30: RealVideo 8
- RV40: RealVideo 9; RealVideo 9 EHQ; RealVideo 10
It should be noted that currently the RealMedia format is used mainly as a format for broadcast quality web radios.
Flash Video Format
Frequently used on the Internet, the so-called Flash Video container was one of the most popular formats, thanks to the spread mass obtained by sites such as YouTube.
The container format called Flash Video is nothing but the well known FLV, which has been developed by Adobe in order to provide a suitable format for streaming video over the Internet, for which Adobe Flash Player is used, met some years ago under the name Macromedia Flash Player. One of the highlights of this format is precisely that the FLV audiovisual content can be embedded within of SWF files type.
The biggest advantage of this format is that a FLV video can be viewed on almost all existing operating systems today, through the installation of the plugin Adobe Flash Player, which is available for free for almost all the existing web browsers.
Moreover, the plugin can also be incorporated into various media players such as MPlayer, VLC Media Player, Media Player Classic, Windows Media Player, among others, which allows viewing a video FLV on computer without drawbacks.
Programs for video playback that have support for viewing videos in FLV format, ie whose extension “.flv” are among others BitComet FLV Player, K-Lite Codec Pack, MPlayer, KMplayer, Kaffeine, RealPlayer, VLC Media player, Xine, Winamp, Media Player Classic, Windows Media Player and JavaFX.
Note that in regard to the audio tracks that accompany the FLV video, usually it is an audio encoded in MP3 format, while others use the Nellymoser format. However, these files also has support for ADPCM audio format.
Mobile 3GP format
With the increasingly widespread use of cell phones and the possibility they offer in terms of functionality, users often perform a variety of tasks with your phone, including video capture and playback.
For this, one of the most common format used by most cell phones was the called 3GP, what was a container in which you can store information from various media, both video and audio.
Created by 3rd Generation Partnership Project (3GPP) file format digital video was a simplified version of “ISO 14496-1 Media Format”, and whose main characteristic is that it is similar to Quicktime format.
To achieve its mission, ie provide video files with audio really small in size, it uses the MPEG-4 or H.263 for video codecs and AMR-NB or AAC-LC formats for audio.
Moreover, to achieve full compatibility with mobile phones, 3GP format specifications include GSM, and GPRS and EDGE, and W-CDMA capabilities.
To play these videos, whose extension is “.3gp”, you must use a media player that includes the necessary codecs. Most players are usually compatible such as VLC Media player, Totem, Media Player Classic, KMPlayer, QuickTime, RealPlayer, GOM Player and Windows Media Player.
It should be noted that currently, smartphones can play all kinds of video and audio formats without problems, thanks to its powerful processors and RAM.
The digital Matroska container has become in recent years one of the most widely used, especially by those users looking for a digital format to gather a lot of information.
In principle, we must emphasize that Matroska is an open standard container type. By this we mean that its biggest feature lies in the fact that a computer file can itself contain an unlimited amount of content, such as video, audio, pictures, and even special text files such as subtitles.
For this reason, the term Matroska was chosen to define this type of container format because its developers were inspired by the concept of the popular Russian dolls called “matryoshka”.
Arisen under the premise of achieving become a universal format for storing serve diverse audiovisual content, you can make certain similarities with other containers of its kind, as in the case of AVI.
The biggest difference with other containers is that Matroska is an open standard, and most of its features come from developments created from the bases of free software.
Due to this, Matroska can be used freely by all those interested, besides allowing his free distribution, since the format is licensed under the GNU LGPL.
The Matroska files can be identified by their extensions, which can be:
- MKV: for video that also contains audio and subtitle files
- MKA: Files with only audio
- MKS: for subtitles
Within the various formats of multimedia containers today, perhaps one of the most interesting, yet less exploited, is the so-called Ogg Media, which has not yet succeeded in gaining an important place in the market.
For those unfamiliar with this format, the first thing to clarify is that generally most expert users refer to it as OGM, acronym from the name Ogg Media.
Basically, OGM is a multimedia container, whose extension is “.ogm” which was developed almost by accident by Tobias Waldvogel, who was seeking a new container to store audiovisual material in format digital.
In fact, GM is basically a modification of the Ogg container, which was designed to become the main alternative to AVI, which provides the ability to contain inside all kinds of video and audio formats. However, within a OGM file we can find others codecs, including DivX or Xvid video, audio tracks from Vorbis format, and subtitle tracks.
Among the main features of this container, it is noteworthy that only allows a single video track inside, which can be accompanied by several audio tracks in different formats, beside of multiple subtitles.
On the other hand, it includes native support variable bitrate audio, provides the possibility of including several chapters into one file, searchable smoothly without desynchronization, and also has support for streaming. Compared to the AVI container, the GMO has better tolerance for errors, but it is larger than an AVI with same quality.
In recent years, the Xvid codec was one of the most used in the multimedia world, as it allows for a good result in terms of image quality and is a project that emerged from the world of free software. The Xvid format lost many popularity when it appeared on the market the MP4 format, which allows HD video quality in a small file size.
To begin, it is important to mention that is called Xvid to the video codec that meets the standards set by the MPEG-4, and has been developed by a group of programmers around the world, as a free project and open source.
Created as an alternative to commercial video codecs, Xvid managed to prevail in the multimedia market, even surpassing the popular DivX in frequent use, so it can be said that this is one of the most used files video codecs for exchange on the network.
One of the biggest advantages of this codec is precisely the fact that it is a free open source project, which means it provides the possibility of a total configuration of its parameters, and offers a real compatibility with almost all players, even the DivX.
Basically, Xvid works by generating lossy compression, meaning that the result will be lower in terms of quality that the original source. In this sense, if for example we compress a DVD movie in Xvid codec, we can make the resulting file will only reach a size of 700 Mb, suitable to be recorded on optical media such as CD.
Usually, the video containing such files is accompanied by audio tracks in MP3 format, but may also include audio in AC3, giving excellent reproduction quality, even in 5 channels.
Importantly, to compress a file in this format, as well as to play a video encoded with Xvid, you must install the appropriate codec system, which can be downloaded for free in this link.