all_about_DVD

FAQ: 

 TV Standards

Standard for camcorders. Has 720 x 480 pixels and compresses 5:1.

One second requires 3.6 MB of storage space so one GB holds 4.6 minutes.

A video signal made of binary digits. To store and manipulate analog video on a computer workstation, it must be converted to digital video.
Digital video is usually compressed because it takes Terabytes (thousands of Gigabytes) to store an uncompressed movie. Because standard lossless compression is insufficient for video, the video codecs have to get rid of irrelevant information - stuff the human eye won't see or is unlikely to see. Since that is still not enough modern compression, algorithms use keyframes and I and P frames to save space
The DV standard (originally known as DVC - Digital Video Cassette) was created by a group of consumer electronics companies, which has grown since and is known as the DV consortium.
It uses a 1/4 inch (6.35mm) metal evaporate tape to record very high quality digital video. The video is sampled 720 pixels per scan line, with 4:1:1 or 4:2:0 chroma (colour) samples.
The video is compressed using DCT (Discrete Cosine Transformation), similar to moving JPEG. DV can achieve better compression than moving JPEG since it allows better optimisation of quantization tables within a frame.
Only intra frame (I-frame) compression is used, meaning that frames do not depend on previous or following frames. This requires less complicated codecs than MPEG and also makes it more suitable for editing, but big bitrates are required to maintain quality levels.
The video bitrate is fixed at about 25 megabits per second (Mbps). The total data bitrate, including error protection and audio streams is about 36 Mbps. DV has 720 x 480 pixels and compresses 5:1.
One second requires 3.6 MB of storage space so one GB holds 4.6 minutes.

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Television format used in the US and Japan.

Resolution is 720 x 480 with 29,97 frames per second.

Most countries around the World use one of three main television broadcast Standards.
These three main standards are NTSC, PAL and SECAM. However, each standard is incompatible with the other. For example, a video recording made in the UK could not be played on US standard VCR's or shown on the TV.
The first colour TV broadcast system was implemented in the United States in 1953. This was based on the NTSC (National Television System Committee) standard. NTSC is used by many countries on the American continent as well as many Asian countries including Japan.
NTSC runs on 525 lines/frame.

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Television format used in Europe, Asia and Australia.

Resolution is 720 x 575 using 25 frames per second.

Most countries around the World use one of three main television broadcast Standards.
These three main standards are NTSC, PAL and SECAM. However, each standard is incompatible with the other. For example, a video recording made in the UK could not be played on US standard VCR's or shown on the TV.
The PAL (Phase Alternating Line) standard was introduced in the early 1960's and implemented in most European countries except for France.
The PAL standard utilises a wider channel bandwidth than NTSC which allows for better picture quality. PAL runs on 625 lines/frame.

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Television format used in France and Canada.

Same resolution and framerate as PAL (720 x 576, 25).

Most countries around the World use one of
three main television broadcast Standards.
These three main standards are NTSC, PAL and SECAM. However, each standard is incompatible with the other. For example, a video recording made in the UK could not be played on US standard VCR's or shown on the TV.
The SECAM (Sequential Couleur Avec Memoire or Sequential Colour with Memory) standard was introduced in the early 1960's and implemented in France. SECAM uses the same bandwidth as PAL but transmits the colour information sequentially.
SECAM runs on 625 lines/frame.

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