Questions and answers about MP4


Free Download Mp4Gain
picture

Questions and answers about MP4

Mp4

Movies recorded in the MPEG-4 format have already gained deserved popularity among a wide audience of PC users. These films usually fit on a CD and, in terms of image quality, they can compete successfully with video tapes. Not the last factor that determines the popularity of MPEG-4 discs is their price – 60-70 rubles. against 400-600 p. for the DVD. Therefore, MPEG-4 could well become a middle ground on the path of the massive transition of home users from analog VHS video recorders to the digital standard DVD.

MP4

In the Russian-language part of the Internet, you can find a large number of materials about the MPEG-4 standard, but most of them contain a description of the complexities of the process of compressing video in this format. This is, of course, a specific question that requires detailed research, but for users acting only as viewers, these articles often cannot answer the questions that arise when they want to watch movies. Another important source of information is conferences. In the “Processors”, “Video”, “Multimedia” sections, issues related to speed, quality, optimal settings and everything related to MPEG-4 are constantly raised, but the answers received often contradict each other. Someone claims that all his life he watched MPEG-4 without brakes on Pentium 200, others complain about the slideshow,

This article attempts to clarify frequently asked questions from people who have recently encountered this format, as well as to draw the attention of those who have never encountered MPEG-4 before. Hopefully, after reading this material, the reader who is not involved in video editing and compression will be able to safely say, “Now I know enough about this.”

What is MPEG?
MPEG is an abbreviation that stands for Moving Picture Experts Group (before writing a letter the first letter is not deciphered, so go to www.mpeg.org).

It is a fairly large organization, consisting of developers of audio, video and computer equipment, as well as programmers and specialists involved in the development and implementation of standards for algorithms for compression, transmission, storage and reproduction of audio and video data.

Among the developments of this group in the field of digital video recording, the most famous are:

MPEG-1 standard. It was released in 1992. Users most often associate it with movies on VideoCD. The typical consumer video format for MPEG-1 in the PAL standard is 352 * 288 pixels, 25 frames per second. The audio part is stereo audio with a sampling frequency of 44.1 kHz, compressed in MPEG-1 Layer II. A feature film recorded in this format occupies two CDs in the VideoCD standard. The picture quality of VideoCDs is on par with a consumer VHS videotape.

MPEG-2 standard. Released in 1995. Users come across this video compression format primarily when purchasing DVD with movies. The typical frame size for a PAL / SECAM video DVD movie is 720 * 576 at 25 frames per second, or 640 * 480 at 30 frames per second in the NTSC standard. Compared to MPEG-1, the audio part adds support for multi-channel sound (Dolby Digital 5.1, DTS, etc.). Increasing the bit rate and using an improved video compression algorithm have given DVD movies much better picture quality than VideoCD. MPEG-2 is also used today in digital satellite television. Home DVD players in our country are gaining popularity. The relatively high price of DVD movies plays a big role in this.

MPEG-4 standard. Its development began in the first half of the 90s of the last century. In December 1999, a launch of this format was presented, which received the official status of the ISO / IEC standard. MPEG-4 was conceived as a way to transfer data from transmission media, mainly video, over low-bandwidth channels. The standard unexpectedly gained popularity among low-budget users: the use of more complex compression algorithms made it possible to put one-and-a-half-hour to two-hour feature films in acceptable quality on a single CD. With the same bit rate and certain encoding conditions, the image quality of a movie in MPEG-4 can be comparable or even better than when using MPEG-1 or MPEG-2. However, the use of new compression algorithms also significantly increased the requirements for the computational resources necessary for decompressing high-quality images from this format.


Free Download Mp4Gain
picture


Mp4Gain Main Window
picture


Mp4Gain Features
picture


Free Download Mp4Gain
picture

Mpeg-4, start the countdown in Europe

Countdown to a double shutdown, which will force millions of Europeans to change their television or mount a special decoder. In fact, the first (small) television revolution is eight months away: as of January 1, digital terrestrial broadcasts will use only Mpeg-4 encoding, abandoning the now-old Mpeg-2.

 MPEG-2  MPEG-4

As of July 2022 the second (major) revolution: all transmissions will go in Dvb-t2 (the second digital terrestrial transmission standard), with Hevc encoding (which allows greater compression than simple Mpeg-4 and therefore more channels and / or better quality). A double revolution made necessary by the arrival of 5G, which from 2022 will also use the 700 Mhz frequencies that televisions now use.

video quality

It is good to arrive prepared for these dates, taking into account everything that is at stake. On the one hand, the risk not only of not being able to see terrestrial digital but also of not being able to enjoy the advantages of Hevc, soon adopted by other platforms (such as Netflix, which has already announced it).

On the other hand, the possibility of being able to have state incentives for switching to a suitable television or decoder: 25 euros per hour provided only for a small audience of users (over 75, exempt from the Rai rate and with a maximum income of 8 thousand euros per year), but in the future perhaps extendable by means of new decrees to a greater number of users. The earliest deadline: January 2020 Mpeg-4 Mpeg-4 is the normal encoding that we are used to having on internet videos since the early days of broadband, while Mpeg-2 dates back to the days of DVD. AND

He first manages to bring more content in the same space (disk or radio) and therefore even thanks to this step it will be possible to start releasing some frequencies for 5G of the 700 MHz band. The good news is that for more than one Europeans of the decade have MPEG-4, but according to Mise’s estimates there are around 10 million still stationary on MPEG-2.

Please note that the change in frequencies will be gradual, from January 2020 to December 2021, in the various regions of Italy (according to a roadmap defined by the Government). Two years in which it could also happen that, apart from the Mpeg-4 issue, due to this move it will be necessary to intervene in the condominium system for a readjustment. To understand if our TV (now prehistoric) fits into these, simply connect to the HD channels of digital terrestrial (from 501 onwards): if an error message appears and we cannot see the signal, it means that we do not have the MPEG-4.

They are high definition channels precisely because the best compression allows you to increase the amount of usable data for the same amount of space. Or to occupy less while maintaining the same amount of data (that is, the same number of channels with standard quality), which is precisely the advantage of being able to release frequencies of 700 MHz for 5G. It is enough to take a very cheap “zapper” decoder to adapt TV to MPEG-4, but perhaps it could be an opportunity for a more substantial upgrade, which looks to the future.

Second deadline: July 2022 After just over two years, in fact, we will already need support for DVBT-2 and Hevc codecs, which make signal transmission and compression even more efficient. Which means the possibility both of saving other frequencies and, above all, of changing many of the current channels to 4K. Since January 2017, all televisions integrate the two technologies by law. If we have a TV released before this date, it will be good to do an internet search to read if its specs include Dvbt-2 and Hevc.

However, if not, it may be helpful to wait a little longer before switching to a new model. Until July 2020 we do not need those two technologies for digital terrestrial; If we still do not perceive our TV as obsolete, for our uses, we must wait. If nothing else, in this way we can save money by buying a television that by then will not be so recent but will already be equipped with DVBT-2 and Hevc. It is also possible that the Government will slightly expand the audience of the beneficiaries of the television bonus . if we find, on a deadline, with several families that are not yet equipped with compatible devices. One reason to accelerate the switch to Hevc could be the adoption of Netflix. That thanks to the new codec it will be possible to give 4K even to those who have a line that is not really ultra-broadband and offer 8K content to a wider audience of people.

What is the difference between MP3 and Mp4?

MP3 and MP4, what are the differences?

Many wonder if MP4 is in all respects an “improved version” of MP3. The answer to this question is definitely “NO”, as these are two different types of file data.

mp3

In fact, MP3s refer only to the audio encoding aspect, while MP4s also store images, videos, text and subtitles, so in this case we are talking about a real digital container of different types of information.

Mp4

To better understand what the differences are between the two formats, let’s take a closer look at both.

MP3, history and functions

Designed by the Moving Picture group of experts and introduced to the world in the early 1990s, MP3, short for MPEG-1 Audio Layer 3, is an audio format that has revolutionized the concept of music and its portability.

Its operation is based on a specific lossy compression algorithm that allows to significantly reduce the volume of data useful for playing an audio track, called Lossy (translated: Loss).

Despite this compression, the end result remains faithful to the original recording for the vast majority of users.
In practice, any frequency considered imperceptible to the human ear is considered “removable”.

What does all this imply? Simple! The resulting MP3 file will be extremely smaller than the starting track, therefore, at a volume that previously could only hold 20 music files, hundreds of MP3 tracks can be stored.

MP4, history and features

The release of MP4, or MPEG4 Part 14, dates back to the early 2000s, precisely to 2002, and is used for digital video and audio broadcasts, images, and subtitles.

It is defined as a multimedia container in standard format or part of MPEG4 and does not have a standard information encoding method.

MP4 technology is based on the Apple QuickTime MOV format with, in addition, support for different MPEGs and higher quality audio expressed in AAC (Advanced Audio Coding) format.

From all this it can be understood that MP4 can be audio, video or audio + video files at the same time, also considering the possible presence of images or subtitles.

This is, for example, the most widely used format in the ever-evolving world of digital television and mobile video telephony.

Remember that the two extensions MP4 and M4A indicate the same type of file, what changes is only the extension and, in most cases, you can rename a specific file so that it is suitable for reading by the program.

Bottom line: when to use MP3 and MP4?

Finally, when should you choose an MP3 or MP4 format?

In the event that your file is exclusively an audio track, to be listened to while you are running and to be played through a small portable device, it is good to convert your songs to MP3 format.

This will take up less space on your device, preserve good audio quality, and can store many more songs in the player’s memory.

If, on the other hand, the files you are interested in are videos, perhaps accompanied by audio, images and subtitles, and they will be played on a device with a screen, the format I recommend is undoubtedly MP4.