which video formats are supported by iphone Archives

Types of videos

Free Download Mp4Gain

Types of videos

MPEG-1

The MPEG-1 video compression format was developed by the Motion Picture Expert Group, an international organization that creates video compression standards. It supports a maximum frame resolution of 4095 x 4095 pixels at a frame rate of up to 60 times per second. However, a resolution of 352 x 288 is generally used, which corresponds to the quality of recording on a normal VHS cassette.

How is the information compressed in this format? Suppose we have the following scene: the car moves from point “A” to point “B”. The movement of the machine can be described by two parameters: the vector of movement from point “A” to point “B” and the angle of rotation around its axis. At the same time, the background remains unchanged or almost unchanged: the viewer is unlikely to pay attention to the vibrations of small branches near distant trees. So you can divide the frame into two components: the background, which is saved once and then replaced during all-frame playback, and the area where the car moves, will have to be recorded separately for each frame.

Digital video: an overview of formats

In MPEG-1 format, all frames in a movie are classified into three types: I, P, and B frames. The first type (I-frames, Intra Frames) includes anchor frames. Your images are saved in their entirety in JPEG format. For the predicted frames, only the differences from the previous i-frame are recorded, which requires much less disk space. For B-frames (bidirectionally interpolated frames), the differences with the previous and next I or P-frames are preserved (Fig. 2).

Digital video: an overview of formats

As a result, the compressed file size is approximately 1/35 of the original. This means that an hour and a half movie with the quality equivalent to an analog VHS cassette in MPEG-1 format will fit on two CDs. For transmission over the Internet or in satellite transmission networks, this standard, of course, is not suitable. But there have been many consumer video CD players that work in this format (and they are still being produced now, by the way).

MPEG-2

MPEG-2 is an additional extension of MPEG-1. The recommended frame size has been increased; it is now 1920 x x 1080 pixels, added support for six channel audio. However, playing video in this format requires more processing power from your computer.

It should be noted that work was underway to create the MPEG-3 standard (not to be confused with the now popular audio compression format: MPEG-1 Audio Layer 3). It was supposed to become the basis for HDTV digital television systems. But the work was interrupted, because the necessary requirements for HDTV were implemented in the form of small extensions of MPEG-2.

This format is now quite widespread in the West: it is used to transmit video through satellite channels and digital cable networks, in addition, all DVD video discs are recorded in this format.

MJPEG

In fact, MJPEG (Motion JPEG) is a transition format from compressing normal photos to compressing videos. Each frame is recorded in JPEG format and then placed in the footage. MJPEG is mainly used in video editing cards like Fast AV Master, MiroVideo DC50, etc. You can reduce the video stream from 30MBps to 6MBps. For use in home video players, this standard is not very suitable due to the low compression ratio (5: 1) and the lack of means to synchronize video and sound.

MPEG-4

The MPEG-1 and MPEG-2 formats did not provide a real possibility to transmit video over the Internet and create interactive television based on them: the file size was too large. To drastically reduce it, as well as implement other functions necessary for video transmission, work has begun on the specifications of a new format: MPEG-4. In fact, it does not focus so much on video compression as on the creation of so-called “multimedia content”: the fusion of interactive television, 3D graphics, text, and so on.

As for the video itself, the most important innovation was the further improvement of technologies for decomposing a scene into objects and algorithms for their effective compression. Thus, for example, when compressing a video recording of a tennis match, most of the frames can be conditionally decomposed into images of the stands (background) and the players.

Free Download Mp4Gain

Mp4Gain Main Window

Mp4Gain Features

Free Download Mp4Gain

Video compression formats

Video compression formats

Before building a video surveillance system, a technician will have to solve a number of critical problems and tasks. Along with the choice of cameras, servers, and software, it is necessary to select the optimal compression format for the system’s video transmission. The main formats for video surveillance systems are MJPEG, MPEG-4 and H.264 (MPEG-4 part 10). Controversy “Which format is better?” Similar to the disputes “what is the future for: analog or ip?”, have been going on for several years, but experts still cannot reach a consensus. In this article we will talk about the characteristics of the formats, the parameters that must be taken into account when choosing, and the technologies used to analyze video streams.

Compress video

The videos from the IP surveillance cameras reach the server in compressed form. Compression generally involves removing features that are almost invisible to the human eye, although compression is sometimes done without loss of information. Compressed video stream requires less network bandwidth and less free hard disk space. To view or analyze the video, the resulting stream must be unzipped; apply the reverse conversion algorithm to compression. The combination of compression and decompression algorithms is called a video codec. Video codecs of different standards are not compatible with each other; video information compressed with one codec, as a rule, cannot be decompressed with another.

There are several types of compression.

Lossless compression allows you to obtain an image after decoding that does not differ from the original frame.
Lossy compression loses information after decoding.

Several lossy compression implementations are possible:

lossy percentage compression – loss is so insignificant to the human eye that the frame before and after decoding is virtually indistinguishable to the operator;
lossy compression – the differences between the frames before and after decoding are noticeable, but still not very pronounced, all the information necessary to analyze the events is saved;
Lossy Compression: Low-quality streaming video compression, causing artifacts (noticeable video distortion) during decoding. The appearance of artifacts leads to a decrease in image clarity, the appearance of fields of the same color (when different color tones are combined in one), the appearance of image blockages (pixelation, graininess). The presence of artifacts leads to false results of the analysis of the video stream by the system software.
In the compression process, to reduce the size of the video stream, the amount of color tones in the image are reduced, color resolutions are lowered, and small details in the image that are invisible to the human eye are removed; predict changes based on data already received; remove duplicate pixel values.

Video compression formats

There are many compression formats, MJPEG, MPEG-4 and H.264 are the most popular in video surveillance.

MJPEG format

For the MJPEG compression format, a video sequence is a sequence of still images: JPEG images. Compression occurs individually for each frame (intraframe). We get total independence from individual images. When playing a video file, the image quality is still good: from the MJPEG format you can always get frames with a clear image of the events that take place, it does not require high processor performance, but significantly loads the network and requires a large amount of disk space. This format is characterized by image blocking artifacts, fields of the same color. Camera data is lossy, so it’s impossible to say there is no distortion. Another thing is that if the camera is correctly adjusted, the human eye in JPEG hardly notices distortion.

MPEG-4 and H.264 formats

For MPEG-4 and H.264 formats, compression is performed both within a frame and for a series of frames (between frames). H.264 video (MPEG-4 optimized or MPEG-4part 10) is not a sequence of individual images, but a chain of related data – video streaming. The advantages of this format are that not all frames are saved, but only the reference image and its subsequent changes.

When a significant part of the image remains unchanged, the resulting video size is much smaller than for MJPEG. In case the MJPEG format can send a set of images of 200 KB each, the H.264 format will send a reference image of 200 KB and its subsequent changes, which are much smaller.

Video format comparison: MOV, FLV, MP4 and 3GP

Video format comparison: MOV, FLV, MP4 and 3GP

Each video file format has its own unique characteristics, which make it ideal for specific uses. This fact forces the user to have to choose between them more and more frequently. The most important criteria in making this decision is which characteristics of the file types best suit your specific needs. To help you choose the best type of video file, here is a list of the pros and cons of the most popular video formats.

The .mov video format

The MOV video file format was developed by Apple with the aim of bringing clear benefits to users. One of these advantages is the high quality of MOV videos. Cinema purists and filmmakers who want to create long digital movies, in particular, are determined by the quality preservation properties of the MOV format. When working with MOV files, optimal video quality will be maintained throughout the project. Although MOV is closely linked to Apple, the files can also be opened with Quicktime Player on Windows.

A major problem with MOV is the lack of support from the various media player applications. Many users have to download new software before they can play MOV video. Also, the files are very large, which requires more hard disk space. This can slow down old hardware.

Ultimately, .mov was designed for a specific group of users, especially those who value high video quality. Even if these files are generally used less frequently, they are of great value to a small target group.

The word ‘video’ is made up of many letter tiles.
With the right video format, projects can be implemented smoothly.

The .flv video format

The FLV video file format stands for Adobe Flash Videos. It is the most widely used type of video file on the Internet. The reason for the enormous popularity of .flv is that the format works optimally in all major browsers. Therefore, leading video portals like YouTube also use Flash videos by default. Another reason for the frequent use of FLV video files is that it is suitable for various video formats, including commercial ones.

There is also a downside to the FLV format: if a lot of Flash videos are hosted on a website, it can get slower overall. This is especially likely to be felt by visitors with slower Internet access. This is still a major problem at this time. As the Internet becomes more accessible, this concern will lessen in the future.

A man is editing a video on a laptop.
The FLV video format sadly affects the loading times of websites.

The video format .mp4

The MP4 video file format offers high-quality video. Unfortunately, the format is not ideal for a single task. But that doesn’t mean that these files don’t have many advantages as well. In fact, MP4 files are so small that they are ideal for storing in a video asset management system. Even at such a small size, the video quality is amazing. They are also great for sharing videos due to their high browser compatibility.

Therefore, it is quite paradoxical that the MP4 format is used as the standard in most photo and video cameras, as it scares filmmakers so much. The reason for this is that .mp4 files do not edit well. Without the proper properties that allow for proper editing and good editing, the MP4 video format does not meet the requirements of one of the potentially most important user groups.

A hand holding a camera lens in the forest.
MP4 videos retain high quality despite their small file size.

The .3gp video format

The 3GP video format corresponds to the Third Generation Partnership Project and is the associated file extension. It can be opened with many programs, is inexpensive in terms of memory requirements, and optimally protects data. It is ideal for mobile devices that cannot cope with high traffic when streaming video to each other.

Also, the .3gp file type has a dominant position in relation to video transmitted via text messaging services. This will continue despite certain weak points.

A key problem with 3GP relates to compression and the difficulties it presents. Users who care about maintaining video quality will be amazed at the end result of compression. Although this deficit is a necessary evil for the sake of functionality, many users still find it negative.

Get familiar with the big differences between video file types. This will allow you to make the right decisions for a successful implementation of future projects. Once you have a solid understanding of video formats, consider using a digital asset management system to manage your video files.

What are video formats?

The term explains how video data is or has been recorded on a data carrier. The type of video data recording is basically defined by four different reference points. These are:

the movie format (image resolution and aspect ratio). Check out Part 1 of this article series titled Film Formats
the refresh rate (also called the refresh rate). The frame rate is specified in hertz (Hz) or as fps (frames per second, German = images per second)
color depth, which describes the ability to differentiate between color values and brightness values
the soundtrack
Regardless of the purpose for which you want to create a video, the video format determines its quality and usability.

The data formats are NOT the same as the video formats. The data format establishes how video data is presented in a purely technically structured manner and is read (interpreted) by software on a computer system for processing.

Data formats have nothing to do with video format, movie formats, frame rates, color depths, and sound. Normal users rarely come into contact with data formats when communicating with movies and videos. The situation is different with data and video formats.

Video formats (“formatted videos”) can be identified by their file extensions (for example, * .mp4 or * .mov or * .mpg). Video formats can be classified according to different criteria, depending on the subject: for example, according to the size and quality of the file (compression) or according to the content type of a file (container formats).

Movie format / aspect ratio difference

Just as data formats represent different things, the terms movie format and video format are NOT identical. In film format in which the question is understood thereafter for film and video, size and in what aspect ratio a film or video is on a recorded disc. Movie format and rotation formats are synonymous, while recording format, image format, image size, and projection format as subgroups further specify the term movie format.

Why is the video format important?

The video format is not important. But only if you watch your videos directly on your smartphone or upload your own videos directly to the Internet. But anyone who wants to communicate professionally with videos will want to edit their movies and will quickly have to deal with not only the content, but the technical quality as well.

Even those who “only” want their movies to be accessible to the public via YouTube or Vimeo or who want to embed their social video on their website via one of these video platforms will notice at the latest that there is something like a technical framework if the video file is not sent to upload is accepted. YouTube, for example, succinctly reports in this case: Before you can upload these types of files, you need to convert them to YouTube-compatible video formats. (The next chapter on conversion provides information on what this means and means.)