In the past few years, depending on the debate has become quite compression is a very popular topic, but interestingly, video signal compression is not a new issue. Play WMV on Mac Many people do not realize, accompanied by the 1950s, the color television video compression first commercialized. Three pictures show the red, blue, green, the highest resolution images of the string, the total 15MHZ occupied with wide, But be compressed into all 5MHZ accounted for only 1 - compound signal compression ratio was introduced the bandwidth. This way is simple, but before compression. WMV to FLV on Mac Of course, this way is through the early compression of simulation technology. Today, more stable and continuous image quality and higher compression string by the analog signals can be converted to digital signals, use some highly complex technology. These technologies eventually brought higher compression efficiency string and finer compressed image processing method. These digital technology to the project is extremely powerful ability, until recently in economy is still not done. Today, however, wmv converter things have changed. Compression is basically a process: seek through video signal exists in the redundancies, to reduce the image or graph as the information group.
Generally speaking, digital video compression from component video expression, this is a signal, brightness is able to express the two. The most widely accepted digital video format is Rccommendation601), the proposal USES the "nodes" model of 4:2:2 sampling structure. video converter Mac So-called "nodes" refers to the total each pixel color by 3 samples to describe a brightness, two color formation of sampling chromaticity sampling. Because these three sampling in time, so the overlap is called "nodes" altogether. In 1843, each frame works in the system is effective, a row 483 is 720 a pixel, In Canada, each frame works system effectively 576 a. DVD Ripper
Through the brightness of the combined sampling chromaticity, does not damage the image quality, at the same time, reduce the bandwidth required to achieve. In the 4:2:2 "4" refers to the four times in digital system adopts the subcarrier sampling frequency. Interestingly, the brightness of sampling frequency on the actual number is 13.5 MHZ: "4" in the use of just 14.3 MHZ NTSC sampling frequency is the legacy of history. The sampling frequency is MH2 1.35 - Mac DVD Creator a compromise, but because it is relatively 525 and 625 line system has an integer. The sampling means "2" refers to the color signal Cb, Cr sampling frequency is just half the brightness of sampling frequency (MHZ) 6.75. The ability to distinguish who limit luminance feature makes this method of sampling frequency for points to use: a wide range of psychological tests have proved for visual requirements such as color key demanding post-production, such application environment MHz 6.75 sampling frequency can reach colour degree is enough. import DVD into iTunes Mac
Compression is basically a process: through video signal exists to eliminate redundancies, the images or image to reduce the information group. rip DVD to MacBook This video signal can be through the analysis of the statistics forecasting. The main part of the signal is certain and forecasting. An extreme example, it is the sine signals are highly forecasting can, because each cycle are the same, and only a mountain, which does not occupy bandwidth. Another example is the extreme, convert AVI to QuickTime Mac noise signal completely unpredictable. When the signal, virtually all of this is between. Compression technology in general is to identify and eliminate these redundancy, thereby reducing the storage and bandwidth needs.
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