请問what is 咩叫dvi　ＤＶＩ( 急 !)

The Digital Visual Interface (DVI) is a video interface standard designed to maximize the visual quality of digital display devices such as flat panel LCD computer displays and digital projectors. It was developed by an industry consortium, the Digital Display Working Group (DDWG). It is designed primarily for carrying uncompressed digital video data to a display. It is partially compatible with the HDMI standard in digital mode (DVI-D).

The DVI interface uses a digital protocol in which the desired illumination of pixels is transmitted as binary data. When the display is driven at its native resolution, it will read each number and apply that brightness to the appropriate pixel. In this way, each pixel in the output buffer of the source device corresponds directly to one pixel in the display device, whereas with an analog signal the appearance of each pixel may be affected by its adjacent pixels as well as by electrical noise and other forms of analog distortion.

Previous standards such as the analog VGA were designed for CRT-based devices and thus did not use discrete time. As the analog source transmits each horizontal line of the image, it varies its output voltage to represent the desired brightness. In a CRT device, this is used to vary the intensity of the scanning beam as it moves across the screen.

However, when using digital displays (such as LCD) with analog signals (such as VGA), there is an array of discrete pixels and a single brightness value must be chosen for each. The decoder does this by sampling the voltage of the input signal at regular intervals. When the source is also a digital device (such as a computer), this can lead to distortion if the samples are not taken at the center of each pixel, and there are also problems with crosstalk.

DVI的英文全名為Digital Visual Interface，中文稱為「數位視訊介面」。是一種視訊介面標準，設計的目標是透過數位化的傳送來強化個人電腦顯示器的畫面品質。目前廣泛應用於LCD，數位投影機等顯示設備上。此標準由顯示業界數家領導廠商所組成的論壇：「數位顯示工作小組」（Digital Display Working Group - DDWG-）制訂。DVI介面可以傳送未壓縮的數位視頻資料到顯示裝置。本規格部分相容於HDMI標準。

DVI介面的協定會使得像素的亮度與色彩訊號從訊號來源（如顯示卡）以二進位方式傳送到顯示裝置。當顯示裝置以其原生解析度被驅動時，僅需讀取DVI傳來的每個像素的數值資料並且套用到正確的位置即可。相對於類比方式傳送的像素資料會受到鄰接像素資料以及電磁雜訊以及其他的類比失真影響，在此方法中，輸出端暫存器中的每個像素都直接對應顯示端的每個像素。使得畫面品質有基本的保障。

在此之前以類比方式傳送視訊資料的標準，如VGA是為了以映像管（陰極射線管）為基礎的顯示裝置而設計，傳送的單位是水平掃瞄線，因此並未使用數位化的離散信號。類比傳送的視訊信號是以變更輸出電壓來控制掃瞄中的電子流束的密度，並藉此來表現亮度以及彩度。

然而當LCD等數位化的顯示裝置開始實用化之後，以類比方式傳送訊號至數位顯示裝置時，該裝置必須以特定頻率將掃瞄線訊號取樣再轉換回數位格式。若取樣出現誤差就會使得畫面品質劣化。且當訊號來源為電腦時，顯示卡將數位的畫面訊號轉換為類比輸出，再被LCD顯示器轉換回數位畫面的流程顯然是多餘的。因此DVI也隨著LCD顯示器成為主流而被廣泛使用。

DVI的英文全名為Digital Visual Interface，中文稱為「數位視訊介面」。是一種視訊介面標準，設計的目標是透過數位化的傳送來強化個人電腦顯示器的畫面品質。目前廣泛應用於LCD，數位投影機等顯示設備上。此標準由顯示業界數家領導廠商所組成的論壇：「數位顯示工作小組」（Digital Display Working Group - DDWG-）制訂。DVI介面可以傳送未壓縮的數位視頻資料到顯示裝置。本規格部分相容於HDMI標準。