frequency;

Audio frequency refers to/represents the range of signals that are audible to the human ear. It is the property of sound that most determines pitch. Ultimately, audio frequency refers to the number of cycles per unit of time. It is measured in hertz (Hz). The general range of audible frequencies is 20 to 20 000 Hz, varying from individual to individual.

track;

A track is a single stream of any audio which contains channel/s. Tracks can be viewed and altered digitally. In the program Audacity, a track is shown in a waveform display.

Digital audio tracks let you store audio data as digital sound values rather than as musical symbols. A digital audio track works like a recording tape that you can include in a musical document and on which you can record whatever you want for subsequent playback.

channel;

Channel refers to an individual discrete audio track. One channel is just one separate stream of audio information. There is only one channel in mono audio sources. More commonly, there are sources that hold two channels - stereo sources. Sources with more than two channels are referred to as multichannel.

stereo;

Audio stereo refers to sound which is divided into two separate channels. These two channels are played back simultaneously via separate speakers. This causes it to create a fuller sound and provide the ability to mix sounds between both channels. Humans hear the world with two ears so using dual sound sources make it more realistic.

The following are examples of stereo sound:

• spreading the instruments in a music track from left to right

• following the action in a video

lossy file formats;

Audio:

• AAC - .mp4 .m4a .3gp

• ATRAC - .oma .aa3

• MP3 - .mp3

• MPEG-1 - .mp2

• Musepack - .mpc .mpp

• WMA - .wma

Still Image:

• CPC - .cpc

• DjVu - .djvu .djv

• JPEG - .jpg .jpeg

Video:

• DV - .dv .dif

• MNG - .mng

• MPEG-1 - .mpg .mpeg .mp2 .mp3 .mpa

• MPEG-2 - .mpg .mpeg .mp2 .mp3 .m2v

• Ogg Theora - .ogv

psychology & perception;

In methods of lossy compression, human psychology and perception is an important factor. This is because in lossy compressions, very little of the information from a file is still there. Without the deception of how the human eye perceives the difference of information, the file would be very noticeably different from the original. Without our minds to 'fill in the blanks', we would recognise the errors and inconsistencies in a lossy compression.

lossy vs lossless;

The method that offers the greatest compression ratio is lossy compression. The compression ratio of lossy video codecs are generally more superior to audio and still-image.
• The video can be compressed immensely at a 100:1 ratio with little visible quality loss.
• Audio can often be compressed at a 10:1 ratio with imperceptible loss of quality
• Still images are also often compressed at a 10:1 ratio.
The compression rate of lossy compression is about 5-6% while the rate of lossless compression ranges from 50 - 60%.

lossy & lossless;

Lossy and lossless compression are terms that describe whether or not, in the compression of file, all original data can be recovered when the file is uncompressed.

Lossy compression reduces a file by permanently eliminating certain information. When the file is uncompressed, only a part of the original information is still there (however, it usually goes unnoticed). Lossy compression is generally used for video and audio where a certain amount of information loss will not be detected.
The JPEG image file uses lossy compression.

With lossless compression, every bit of data that was originally in the file remains after the file is uncompressed. All the information is restored completely. Generally, this type of compression is used for text or spreadsheet files where the loss of data would pose a potential problem.
The GIF image file uses lossless compression.

data compression importance;

Data compression is very important for the 'online world'. When visiting a website, all the picture files that our browser downloads (file extensions like .png, .jpg and .gif) are all compressed. This also includes videos when online.
Files that are relatively large can be compressed so that they are smaller in size. For example, if an mp3 file is 20MB originally, it can be shrunken to around 3-4MB through compression. This makes it easier to transfer data across the Internet (whether by downloading or uploading).

data compression;

Data compression is the process of encoding information using fewer bits than the original representation would use. Like the compression of images, it reduces the size and quality of the data which could then degrade the quality. Essentially, it is the process of encoding large files in order to shrink them down in size.

Data compression ratio is a term used to quantify the reduction in data-representation produced by a data compression algorithm. The compression ratio is:
compressed size
uncompressed size
(compressed size over uncompressed size)

generation loss;

Generation loss refers to the quality and potential increase of file size between subsequent copies of data. Anything that reduces the quality of the representation when copying, and would cause further reduction in quality upon making another copy from the copy, can be considered a form of generation loss.

In video, the video degredation is caused by successive recordings from the original source. It can also refer to the analog duplication of original video recording.

codec;

Codec is a technical name for 'compression/decompression'. It can also stand for 'compressor/decompressor' and 'code/decode'. Essentially, a codec is a computer program that both shrinks large movie files and makes them playable on your computer. Codec programs are required for your media player so that they are playable on your computer. This is useful since large video and music files are difficult to transfer across the Internet quickly. These mathematical codecs were built to encode (shrink) a signal for transmission then decode it for viewing or editing.

They are used in: videoconferencing, streaming media and video editing applications.

video standards;

NTSC

National Television System Committee;

The NTSC format consists of 29.97 interlaced frames of video a second, each consisting of 480 lines of vertical resolution out of a total of 525 (the rest are used for sync, vertical retrace, and other data such as captioning).

PAL

Phase Alternating Line;

PAL describes the way that part of the part of the colour information on the video signal is reversed in phase with each line, which automatically corrects phase errors in the transmission of the signal. The PAL colour system is usually used with a video format that has 625 lines per frame and a refresh rate of 25 frames per second.

SECAM

Sequential Couleur Avec Memoire/Sequential Colour with Memory;

SECAM is an analog television system, using frequency modulation to encode chrominance information. It is so named because it uses memory to store lines of color information, in order to eliminate the color artifacts found on systems using the NTSC standard.

Australia uses the PAL standard.

ieee 1394 port;

An IEEE 1394 port is also known as a FireWire. It is a component originated from Apple which allows connection of peripherals to a computer, such as video cameras. IEEE 1394 ports are like USB ports which are entry points for devices that you want to connect to your computer.

It allows you to get feeds from a high-resolution video camera onto a computer without experiencing issues. It also functions through peer-to-peer network, which means that devices can connect and 'talk' to each other without needing a computer. Because of this, today they have become a standard for high-bandwidth devices.

The following is an image of an IEEE 1394 port:

digital camera & video compression;

rgb;

Red Green Blue;

It is an additive colour model in which the three hues of light - red, green and blue - are added together in various ways so that they may reproduce a broader array of various colours. Essentially, these hues are 'mixed' together to form any colour.

The following is a colour model of RGB:

resolution;

Resolution refers to the sharpness and clarity of an image, or in this case, videos. The resolution is the number of pixels per square inch/dots per inch (dpi). It describes the details a frame holds so the greater the resolution of a frame, the better quality the video is.

The following is a comparison with the same image, each with different resolutions:

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video & movie frame rate;

In terms of video and movie, frame rate is the frequency/rate which each frame is flashed on a screen.

To answer the question, no, videos/movies don't all have the same frame rate. The rate in which the frame flashes varies according to the type/kind of video or movie that is being filmed. In fast-paced action movies or live sports matches, there would be a lot of cuts and varied fps. In slower types of videos/movies, a lower fps can be used. An example could include putting pictures and images together (animation) and changing the frame rate.

frame rate;

Frame rate is the frequency at which an imaging device produces unique consecutive images called frames. Frame rate is used to measure the speed in which a frame stays still.
It is usually expressed as frames per seconds, but in terms of videos, they are expressed as hertz.

ringtones;

RINGTONEESS