1247541 九、發明說明： 【發明所屬之技術領域】 本發明係關於電子節目表，尤其是有關於利用電子節目 表的自動選台方法。 【先前技術】 一般目前在收看電視時，由於可能在節目播出一半後才 開始收看，常無法得知所收看的節目的名稱、内容簡介、已 播出多久、還剩多久時間等資訊。另外一般也無法在電視機 上查詢各電視頻道未來要播出的節目時間表，而必須要查閱 報紙、電視周刊或相關網站。若是要特別要收看某個節目時， 一般的電視也無法預約在那個節目開始播出時，自動換台到 那個節目的頻道以避免錯失收看，這些都讓電視的收視相當 不便。 近年來，有少數的選台器或錄影機開始提供所謂的電子 節目表，使用人町以直接在這些裝置所提供的電子節目表上 查詢節目或設定預約收視，相當方便。由於查詢到節目或預 約收視某節目後，都會需要切換到那個節目播出的頻道，因 此這些具有電子節目表功能的裝置都是内含有解調元件，而 且從有線電視公旬緵線出來的影音訊號是先進入這類裝置， 這類裝置再將它本身輸出的影音訊號接到電視的影音輸入 源。使用時，使用人先將電視切換到以影音輸入源為輸入， 這樣就可以看到适類裝置產生的電子節目表晝面，還可以透 1247541 過這類裝置内建的解調元件，來切換選台到特定的頻道。 但是，這類裝置因為必須具備解調元件，需要較高的製 造成本。另一方面，這類裝置要使用人先將電視切換到影音 輸入源來收看，影音節目訊號經過這類裝置處理過才輸出到 電視，畫面品質必然會有損失。對於有些較高等級的電視使 用人，他們希望最好能直接使用電視所内建的高等級解調元 件來選台並產生晝面，以得到更好的畫質，因此會對這類裝 置產生使用上的疑慮。 【發明内容】 本發明的主要目的在提供一種電子節目表的自動選台方 法，本方法基本上可以搭配任何本身不具備電子節目表的電 視或影音顯示裝置使用，因此可以節省重新購買一台具有電 子節目表功能的電視的花費。 本發明的另一目的是，所提供的電子節目表的自動選台 方法不需要對節目影音訊號做任何的處理，因此完全不影響 電視節目的晝面品質。 基於上述的目的，本發明所提供的電子節目表的自動選 台方法可以搭配任何至少具有一影音輸入界面（例如，具有 至少一組AV輸入端子）、一控制輸入界面（例如，具有一紅 外線界面，可以接受無線遙控器的控制）、可以接收多頻道的 影音的輸入而予以切換的電視或影音顯示裝置。 1247541 本發明所提供的電子節目表的自動選台方法是從一外部 的節目資訊來源獲得有關節目的頻道、起訖時間、名稱、内 容大綱等相關資訊，儲存在一個節目資料庫中，然後利用電 視的畫面來顯示包含這些影音資訊的電子節目表。對於使用 人所選擇的特定節目，本發明是藉著發出電視的選台控制訊 號，來達成自動選台的功能。除了即時的選台之外，本方法 也可以讓使用人用預約的方式，在一特定時間到達時，使電 視自動切換到某一特定頻道。 本方法可以多種方式實施，例如本方法可以一軟體模組 的方式，安裝於一個具備控制與影音輸出界面之運算裝置（例 如、桌上型電腦、筆記型電腦等）並由這個運算裝置來執行。 或者本方法可以完全實施於一個獨立的電子裝置内。 茲配合所附圖示、實施例之詳細說明及申請專利範圍， 將上述及本發明之其他目的與優點詳述於後。然而，當可了 解所附圖示純係為解說本發明之精神而設，不當視為本發明 範疇之定義。有關本發明範疇之定義，請參照所附之申請專 利範圍。 【實施方式】 第1圖係說明依據本發明之第一實施例之系統示意圖。 在此實施例中，如第1圖所示，本發明所提出的電子節目表 的自動選台方法是實施於一個獨立與影音顯示裝置200以外 1247541 的電子節目表選台裝置100。影音顯示裝置200可以是一台 電視或具有類似功能的裝置（本實施例是以電視為例）。影音 顯示裝置200具有至少兩個影音輸入界面210、220 (例如， 一組Cable In的端子與一組AV輸入端子）。在本發明的另一 實施例中，影音顯示裝置200也可以只具有一個影音輸入界 面（以下解釋第二實施例時會進一步說明）。影音顯示裝置 200還有一個控制輸入界面230(例如，一個紅外線接收器）， 以接受一個遙控器（未圖示）的操作控制。在其他的實施例 中，影音顯示裝置200也可以是其他形式的控制界面（例如 RS232、USB等）。影音顯示裝置200内建有一個解調元件 240，以從第一影音輸入界面210所獲得、從一節目訊號源 300、經過一適當連線（例如同轴電纜）的多頻道影音訊號， 切換影音顯示裝置200的顯示（未圖示）到某一個頻道。節 目訊號源300可以是有線電視系統營運商（經由同轴纜線）、 地面無線電視廣播（經由空氣與天線）、或是衛星電視廣播（經 由空氣與衛星接收器），而第一影音輸入界面則是與節目訊號 源匹配之可以接受多頻道影音訊號之輸入端子（例如Cable In 端子、Antenna In端子等）。可以了解的是，影音顯示裝置200 有諸多細節被省略，惟這些細節並無助於本發明精神之闡 述，故於此省略。影音顯示裝置200的無線遙控界面230， 會依據遙控器所發出的換台訊號，指示解調元件240切換到 1247541 某一頻道。 電子節目表選台裝置100至少包含下列元件：運算模組 110、節目資料庫120、第一影音輸出界面130、控制輸出界 面140、使用界面150、以及通訊界面160。運算模組110係 電子節目表選台裝置100的核心，它包含了處理器、記憶體 等相關元件（未圖示），本方法即是以韌體的方式存放於運算 模組110的非揮發性記憶元件内，由運算模組110的處理器 來執行（因此以下本方法即以運算模組110的各種動作來說 明）。 運算模組110是經由通訊界面160，和一通訊網路400 建立連結，以從通訊網路400上的一個節目資訊源500獲得 有關節目的資訊。在一實施例中，這個通訊界面160是一個 網路埠，通訊網路400是公眾網際網路，節目資訊源500則 是網際網路上的一個伺服器，也就是說，運算模組110，利用 數據通訊的方式，從網際網路400的一個伺服器500下載有 關節目的資訊。在另一個實施例中，這個通訊界面160是一 個同軸電纜的接口，通訊網路400是有線電視系統營運商的 - 有線電纜網路，節目資訊源500則是有線電視系統的播放設 備，舉例來說，運算模組110是直接與有線電視的廣播網路 400連接，節目的資訊是隱藏在影音訊號的VBI (Vertical Blanking Interval)裡、或是副載波（Subcarrier)的方式，由 1247541 有線電視系統的播放設備500傳送給運算模組110。在其他的 實施例中，還有許多種可能的實施方式，例如利用GSM/GPRS 的行動電話網路、無線區域網路、FM廣播的副載波、PHS 的行動電話網路等習知技術都可以達成本發明所需要的效 果。此外，運算模組110與節目資訊源500之間的通訊，可 以是雙向的，也可以是單向的。在雙向的情形下（像是透過 網際網路），例如，運算模組110是週期性的向節目資訊源500 發出需求，然後自節目資訊源500下載最新的節目資訊。在 單向的情形下（像是透過有線廣播網路），節目資訊源500可 以是週期性的或不定時的將最新的節目資訊廣播給運算模組 110。除了以上所述，還有諸多實施細節，相信具一般技藝人 士可合理推知或自行實施，故在此不——贅述。 運算模組110將所接收的節目資訊是存放於節目資料庫 120中。這些節目資訊是未來產生電子節目表的資料來源。 節目資料庫120是代表這些所接收節目資訊的結合，它可以 是電子節目表選台裝置100裡一個硬碟、或是一個可抽拔的 記憶卡上的檔案、或是多個檔案。在其他實施例中，節目資 料庫120甚至可以是獨立於電子節目表選台裝置100之外。 節目資訊包括了節目的名稱、起訖時間、内容大綱、頻道號 碼等。 使用界面150是供獨立於電子節目表選台裝置100的使 1247541 用人操作之用。在本實施例中，使用界面150是位於電子節 目表選台裝置100的機身上，包含有數個控制按鍵以及〇〜9 的數字鍵（作為選台之用），以及一個小的顯示幕以顯示操 作訊息。使用人透過這個使用界面150查詢節目資料庫、選 台、或預約收看節目等各項電子節目表操作功能。 當使用人透過這個使用界面150想要查詢節目資料庫 120時，運算模組110自節目資料庫120中擷取相關的節目資 訊，整合成一畫面，將這個晝面轉換產生適當的影音訊號， 並透過第一影音輸出界面130輸出到影音顯示裝置200的第 二影音輸入界面220,而影音顯示裝置200的顯示螢幕（未 圖示）呈現出來。當使用人可以透過使用界面150做翻到下 一頁、回到上一頁、查詢某一頻道、查詢某一節目等功能， 影音顯示裝置200會因為上述的工作原理而呈現適當的畫面 供使用人觀看。第一影音輸出界面130可以有超過一個以 上、種類不同的端子，例如S-端子、RGB端子、VGA端子等 等。視端子的不同，輸出的訊號格式也不同。同樣視端子的 不同，第一影音輸出界面130的輸出端子是和影音顯示裝置 200的相容的第二影音輸入界面220,以一適當的連線方式連 結，例如VGA纜線、同軸電纜等等。 在影音顯示裝置200呈現電子節目表的畫面之前，運算 模組110會先指示控制輸出界面140發出適當的控制訊號， 1247541 經由控制輸入界面230的接收以及解調元件240的處理，將 影音顯示裝置200切換選台至第二影音輸入界面220，以顯 示電子節目表操作畫面。在本實施例中，控制輸出界面140 和制輸入界面230是採用紅外線遙控的做法。由於各種廠牌 的影音顯示裝置200所用的遙控訊號不盡相同，所以本發明 需要採用類似坊間萬用遙控器的做法，先要經歷過一個學習 的程序，以模擬影音顯示裝置200所用的特定的切換影音輸 入源以及換台的遙控訊號，由於這也屬於習知的技術之一， 在此不予贅述。 當使用人透過使用界面150決定要收看特定的節目時， 運算模組110即指示控制輸出界面140發出適當的控制訊 號，經由控制輸入界面230的接收以及解調元件240的處理， 首先將影音顯示裝置200的影音輸入源切回到第一影音輸入 界面210,再將頻道直接切換到使用人所選擇節目的頻道， 此時影音顯示裝置200完全使用它原有的元件來產生電視畫 面，晝面品質完全未受影響。所以，藉著以上所述的方法， 一般無電子節目表功能的影音顯示裝置，使用人同樣可以使 用電子節目表來查詢節目，同時完全不影響電視節目的畫面 品質。 第2圖係說明依據本發明之一實施例之所呈現之電子節 目表之示意圖。在此例中，使用人正在查詢所有頻道目前播 12 1247541 出的節目，若使用人決定收看第56頻道的「亂世佳人」，影 音顯示裝置200會先被電子節目表選台裝置100模擬的遙控 訊號切回到第一影音輸入界面210為影音輸入源，然後再被 電子節目表選台裝置100模擬的遙控訊號切換到第56頻道。 使用人也可以透過使用界面150預約指定收看某一節 目，也就是說如果使用人指定的節目的播放時間還未到的 話，運算模組110會將這個節目的頻道與開始播放時間記錄 在運算模組110内的預約定時模組170内的非揮發性記憶體 裡。這個預約定時模組170裡還包括有實時計時器（Real Time Clock)，藉由週期性的比對實時計時器與預約的開始播放時 間，當使用人指定的節目的開始播放時間到達時，預約定時 模組170會利用中斷（Interrupt)的機制，自動觸發運算模組 110將頻道切換為該預約的頻道。 在此實施例中，影音顯示裝置200至少需要有兩組的影 音輸入界面，但是因為市面上還有很多影音顯示裝置只有一 組影音輸入界面，對於這些裝置，本發明可以第3圖所示的 做法來提供電子節目表的自動選台功能。第3圖係說明依據 本發明之第二實施例之系統示意圖。如第3圖所示，在電子 節目表選台裝置1〇〇的第二影音輸出界面190和影音顯示裝 置200的第一影音輸入界面210之間，多了一個影音訊號混 合裝置600,此外在電子節目表選台裝置100的運算模組110 13 1247541 裡也多了一個影音調變模組180。影音調變模組180是將節 目資訊所構成的電子節目表畫面的影音訊號，調變到一個特 定的頻道。這個頻道是使用人透過使用界面150所加以設定 的，通常是一個沒有使用到的空的頻道。影音訊號混合裝置 600則同時接收來自電子節目表選台裝置100的第二影音輸 出界面190的電子節目表的位於特定頻道的視訊訊號（經由 第三影音輸入界面620)，以及從節目訊號源而來的多頻道的 視訊訊號（第四影音輸入界面630)，將兩者加以混合，再一 同經由第三影音輸出界面610輸出到影音顯示裝置200的第 一影音輸入界面210。請注意到上述界面之間的影音連線， 均係透過匹配之界面形式與適當之纜線。例如，影音訊號混 合裝置600的第四影音輸入界面630是可以接受節目訊號源 300的多頻道影音訊號之輸入端子（例如Cable In端子、 Antenna In端子等），而影音訊號混合裝置600的第三影音輸 入界面620、第三影音輸出界面610、以及電子節目表選台裝 置100的第二影音輸出界面190也都是可以接受多頻道影音 訊號之輸出入端子（例如Cable In端子、Cable Out端子等）。 另外也請注意到，該影音訊號混合裝置600非本發明之一部 份，而係坊間可輕易取得之影音訊號混合裝置。 在此實施例中，當使用人要使用電子節目表時，電子節 目表選台裝置1〇〇即控制影音顯示裝置200換台至電子節目 14 1247541 表的畫面頻道。當使用者在觀看電子節目表，決定要收看某 節目時，電子節目表選台裝置100即控制影音顯示裝置200 換台至該節目所播出的頻道。 藉由以上較佳具體實施例之詳述，係希望能更加清楚描 述本創作之特徵與精神，而並非以上述所揭露的較佳具體實 霹 施例來對本創作之範壽加以限制。相反地，其目的是希望能 涵蓋各種改變及具相等性的安排於本創作所欲申請之專利範 f 圍的範疇内。 籲 【圖式簡單說明】 第1圖係說明依據本發明之第一實施例之系統示意圖。 第2圖係說明依據本發明之一實施例之所呈現之電子節目表 之示意圖。 第3圖係說明依據本發明之第二實施例之系統示意圖。 【主要元件符號說明】 _ 100 電子節目表選台裝置 110 運算模組 120 節目資料庫 130 第一影音輸出界面 140 控制輸出界面 150 使用界面 160 通訊界面 170 預約定時模組 180 影音調變模組 190 第二影音輸出界面 200 影音顯示裝置 210 第一影音輸入界面 220 第二影音輸入界面 15 1247541 230 控制輸入界面 240 解調元件 300 節目訊號源 400 通訊網路 500 節目資訊源 600 影音訊號混合裝置 610 第三影音輸出界面 620 第三影音輸入界面 630 弟四影音輸入界面1247541 IX. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to an electronic program guide, and more particularly to an automatic channel selection method using an electronic program guide. [Prior Art] Generally, when watching TV, it is possible to start watching when the program is broadcasted halfway. It is often impossible to know the name of the program being watched, the content profile, how long it has been broadcast, and how long it has left. In addition, it is generally not possible to check the schedule of the programs to be broadcasted by each TV channel on the TV. It is necessary to check the newspapers, TV weekly or related websites. If a particular program is to be watched, the general TV cannot make an appointment. When the program starts to air, the channel is automatically changed to the program to avoid missing the viewing, which makes the viewing of the TV quite inconvenient. In recent years, a small number of selectors or video recorders have begun to provide so-called electronic program listings, and it is quite convenient for the user to search for programs or set appointment reservations directly on the electronic program schedules provided by these devices. Since the program is called or the program is scheduled to be viewed, it is necessary to switch to the channel broadcasted by that program. Therefore, these devices with the function of the electronic program list all contain demodulation elements, and the video and audio from the cable TV are released. The signal is first entered into such a device, and the device then connects the audio and video signals output by itself to the video input source of the television. In use, the user first switches the TV to input with the audio and video input source, so that the electronic program table generated by the suitable device can be seen, and the demodulation component built in the device can be switched through 1247541. Select a channel to a specific channel. However, such devices require a high cost because they must have demodulation elements. On the other hand, such devices require the user to switch the television to the audio and video input source to watch, and the video and audio program signals are processed by such devices before being output to the television, and the picture quality is inevitably lost. For some higher-level TV users, they hope that it is better to use the high-level demodulation components built into the TV to select the table and create the picture for better picture quality. Doubts about use. SUMMARY OF THE INVENTION The main object of the present invention is to provide an automatic channel selection method for an electronic program guide. The method can basically be used with any television or video display device that does not have an electronic program guide, so that it can save a new purchase. The cost of the TV with the electronic program schedule function. Another object of the present invention is to provide an automatic channel selection method for an electronic program guide that does not require any processing of the program video and audio signals, and thus does not affect the quality of the television program at all. Based on the above objective, the automatic channel selection method of the electronic program guide provided by the present invention can be combined with any at least one video input interface (for example, having at least one set of AV input terminals) and a control input interface (for example, having an infrared interface). , can accept the control of the wireless remote control), can receive the multi-channel audio and video input and switch to the TV or video display device. 1247541 The automatic channel selection method of the electronic program table provided by the invention obtains relevant information about the channel, the starting time, the name, the content outline and the like of the program from an external program information source, stores it in a program database, and then uses the television. The screen displays an electronic program listing containing these audio and video information. For a particular program selected by the user, the present invention achieves the function of automatic channel selection by issuing a channel selection control signal for the television. In addition to the instant channel selection, the method also allows the user to automatically switch the television to a particular channel upon arrival at a particular time. The method can be implemented in various ways. For example, the method can be installed on a computing device (for example, a desktop computer, a notebook computer, etc.) having a control and video output interface by a software module, and executed by the computing device. . Or the method can be fully implemented in a separate electronic device. The above and other objects and advantages of the present invention will be described in detail with reference to the accompanying drawings and claims. However, it is to be understood that the appended drawings are merely illustrative of the scope of the invention. For the definition of the scope of the invention, please refer to the attached patent application. [Embodiment] Fig. 1 is a schematic view showing a system according to a first embodiment of the present invention. In this embodiment, as shown in Fig. 1, the automatic channel selection method of the electronic program guide proposed by the present invention is implemented in an electronic program table selection device 100 of 1247541 which is independent of the audio-visual display device 200. The video display device 200 may be a television or a device having similar functions (this embodiment is a television as an example). The video display device 200 has at least two video input interfaces 210, 220 (e.g., a set of Cable In terminals and a set of AV input terminals). In another embodiment of the present invention, the video display device 200 may have only one video input interface (which will be further explained below in explaining the second embodiment). The video display device 200 also has a control input interface 230 (e.g., an infrared receiver) for accepting operational control of a remote control (not shown). In other embodiments, the video display device 200 can also be other forms of control interface (e.g., RS232, USB, etc.). The audio-visual display device 200 has a demodulation component 240 built therein for switching audio and video signals obtained from the first video input interface 210 from a program signal source 300 through a suitable connection (for example, a coaxial cable). A display (not shown) of the display device 200 is applied to a certain channel. The program signal source 300 can be a cable television system operator (via coaxial cable), terrestrial wireless television broadcast (via air and antenna), or satellite television broadcast (via air and satellite receiver), and the first video input interface It is an input terminal (such as Cable In terminal, Antenna In terminal, etc.) that can match the source of the program signal and can accept multi-channel audio and video signals. It can be understood that many details have been omitted from the audio-visual display device 200, but these details are not helpful in explaining the spirit of the present invention, and therefore are omitted here. The wireless remote control interface 230 of the video display device 200 instructs the demodulation component 240 to switch to a channel of 1247541 according to the channel change signal sent by the remote controller. The electronic program table selection device 100 includes at least the following components: a computing module 110, a program library 120, a first video output interface 130, a control output interface 140, a usage interface 150, and a communication interface 160. The computing module 110 is the core of the electronic program table selection device 100, and includes related components (not shown) such as a processor and a memory. The method is a non-volatile storage of the computing module 110 in a firmware manner. The memory element is executed by the processor of the arithmetic module 110 (therefore, the present method is described by various operations of the arithmetic module 110). The computing module 110 is coupled to a communication network 400 via the communication interface 160 to obtain information about the program from a program information source 500 on the communication network 400. In one embodiment, the communication interface 160 is a network port, the communication network 400 is a public internet network, and the program information source 500 is a server on the Internet, that is, the computing module 110 utilizes data. In the manner of communication, information about the program is downloaded from a server 500 of the Internet 400. In another embodiment, the communication interface 160 is a coaxial cable interface, the communication network 400 is a cable television network operator, and the program information source 500 is a cable television system playback device, for example. The computing module 110 is directly connected to the broadcast network 400 of the cable television. The information of the program is hidden in the VBI (Vertical Blanking Interval) of the video signal or the subcarrier (Subcarrier) mode, and the 1247541 cable television system The playback device 500 is transmitted to the computing module 110. In other embodiments, there are many possible implementations, such as a mobile phone network using GSM/GPRS, a wireless local area network, a subcarrier of FM broadcast, a mobile phone network of PHS, and the like. The effects required by the present invention are achieved. In addition, the communication between the computing module 110 and the program information source 500 may be bidirectional or unidirectional. In the case of two-way (such as through the Internet), for example, the computing module 110 periodically sends a request to the program information source 500, and then downloads the latest program information from the program information source 500. In a one-way situation (e.g., via a cable broadcast network), the program information source 500 can broadcast the latest program information to the computing module 110 periodically or irregularly. In addition to the above, there are a lot of implementation details, and it is believed that the average skilled person can reasonably infer or implement it himself, so it is not mentioned here. The computing module 110 stores the received program information in the program repository 120. These program information is a source of information for future generation of electronic program listings. The program database 120 is a combination of information of the received programs, which may be a hard disk in the electronic program table selection device 100, or a file on a removable memory card, or a plurality of files. In other embodiments, the program library 120 may even be independent of the electronic program listing device 100. The program information includes the name of the program, the starting time, the content outline, the channel number, and so on. The usage interface 150 is for use by the 1247541 operator independently of the electronic program listing device 100. In this embodiment, the use interface 150 is located on the body of the electronic program guide station selection device 100, and includes a plurality of control buttons and numeric keys of 〇~9 (for channel selection), and a small display screen for display. Operational message. Through the user interface 150, the user can query various program functions such as a program database, a channel selection, or a scheduled viewing program. When the user wants to query the program database 120 through the user interface 150, the computing module 110 retrieves relevant program information from the program database 120, integrates the information into a picture, and converts the picture into an appropriate video signal. The first video output interface 130 is output to the second video input interface 220 of the video display device 200, and a display screen (not shown) of the video display device 200 is presented. When the user can use the interface 150 to turn to the next page, return to the previous page, query a certain channel, query a certain program, and the like, the audio-visual display device 200 presents an appropriate picture for use due to the above working principle. People watch. The first video output interface 130 may have more than one terminal of different types, such as an S-terminal, an RGB terminal, a VGA terminal, and the like. The output signal format is different depending on the terminal. Similarly, depending on the terminal, the output terminal of the first video output interface 130 is a second audio-visual input interface 220 compatible with the audio-visual display device 200, and is connected by a suitable connection, such as a VGA cable, a coaxial cable, or the like. . Before the audio-visual display device 200 presents the screen of the electronic program guide, the computing module 110 first instructs the control output interface 140 to issue an appropriate control signal, and 1247541 passes the control input interface 230 and the demodulation component 240 to process the audio-visual display device. 200 switches the channel selection to the second video input interface 220 to display an electronic program table operation screen. In the present embodiment, the control output interface 140 and the system input interface 230 are practiced by infrared remote control. Since the remote control signals used by the audio and video display devices 200 of various brands are not the same, the present invention needs to adopt a similar universal remote control, and first has to go through a learning program to simulate the specific use of the audio and video display device 200. Switching the video input source and the remote control signal of the channel change, since this is also one of the conventional techniques, it will not be described here. When the user decides to view a specific program through the use interface 150, the operation module 110 instructs the control output interface 140 to issue an appropriate control signal, and receives the video and audio through the reception of the control input interface 230 and the processing of the demodulation element 240. The video input source of the device 200 is switched back to the first video input interface 210, and then the channel is directly switched to the channel of the program selected by the user. At this time, the video display device 200 completely uses its original components to generate a television picture. Quality is completely unaffected. Therefore, by the above-described method, generally, the audio-visual display device without the electronic program guide function can also use the electronic program guide to inquire the program without affecting the picture quality of the television program at all. Figure 2 is a schematic illustration of an electronic program chart presented in accordance with an embodiment of the present invention. In this example, the user is querying all the channels currently broadcasting 12 1247541, and if the user decides to watch the "Gone with the Wind" on channel 56, the video display device 200 will first be remotely simulated by the electronic program table selection device 100. The signal is switched back to the first video input interface 210 as a video input source, and then the remote control signal simulated by the electronic program table selection device 100 is switched to the 56th channel. The user can also subscribe to specify a certain program through the use interface 150, that is, if the playing time of the program designated by the user has not yet arrived, the computing module 110 records the channel and the starting playing time of the program in the operation mode. The non-volatile memory in the reservation timing module 170 in the group 110. The reservation timing module 170 further includes a real time timer (Real Time Clock). The periodic comparison of the real time timer and the scheduled start time of the reservation is made when the start time of the program designated by the user arrives. The timing module 170 automatically triggers the operation module 110 to switch the channel to the reserved channel by using an interrupt mechanism. In this embodiment, the audio-visual display device 200 needs at least two sets of video input interfaces, but since there are many audio-visual display devices on the market, there is only one set of audio-visual input interfaces. For these devices, the present invention can be as shown in FIG. The practice is to provide an automatic channel selection function for electronic program listings. Figure 3 is a schematic view showing the system according to the second embodiment of the present invention. As shown in FIG. 3, between the second video output interface 190 of the electronic program guide selection device 1 and the first video input interface 210 of the audio-visual display device 200, an audio-video mixing device 600 is added, and An audio-video modulation module 180 is also added to the computing module 110 13 1247541 of the electronic program table selection device 100. The video tone modulation module 180 adjusts the video signal of the electronic program guide screen formed by the program information to a specific channel. This channel is set by the user through the use of interface 150, usually an empty channel that is not used. The video signal mixing device 600 simultaneously receives the video signal of the specific channel from the electronic program table of the second video output interface 190 of the electronic program table selection device 100 (via the third video input interface 620), and from the source of the program signal. The multi-channel video signal (fourth video input interface 630) is mixed, and then output to the first video input interface 210 of the video display device 200 via the third video output interface 610. Please note that the audio and video connections between the above interfaces are through the matching interface form and the appropriate cable. For example, the fourth video input interface 630 of the video signal mixing device 600 is an input terminal (for example, a Cable In terminal, an Antenna In terminal, etc.) that can receive the multi-channel video signal of the program signal source 300, and the third of the audio-video mixing device 600. The video input interface 620, the third video output interface 610, and the second video output interface 190 of the electronic program table selection device 100 are also input and output terminals capable of accepting multi-channel audio and video signals (for example, a Cable In terminal, a Cable Out terminal, etc.) ). In addition, please note that the video signal mixing device 600 is not part of the present invention, and the audio and video mixing device can be easily obtained between the departments. In this embodiment, when the user wants to use the electronic program guide, the electronic schedule selection device 1 controls the video display device 200 to switch to the picture channel of the electronic program 14 1247541 table. When the user watches the electronic program schedule and decides to view a certain program, the electronic program table selection device 100 controls the video display device 200 to switch to the channel broadcasted by the program. The features and spirit of the present invention are more clearly described in the above detailed description of the preferred embodiments, and are not intended to limit the scope of the present invention. On the contrary, the purpose is to cover a variety of changes and equivalence arrangements within the scope of the patent application to be applied for in this creation. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing a system according to a first embodiment of the present invention. Figure 2 is a schematic illustration of an electronic program listing presented in accordance with an embodiment of the present invention. Figure 3 is a schematic view of a system in accordance with a second embodiment of the present invention. [Main component symbol description] _ 100 electronic program table selection device 110 operation module 120 program database 130 first video output interface 140 control output interface 150 use interface 160 communication interface 170 reservation timing module 180 video tone modulation module 190 Second video output interface 200 video display device 210 first video input interface 220 second video input interface 15 1247541 230 control input interface 240 demodulation component 300 program signal source 400 communication network 500 program information source 600 video signal mixing device 610 third Audio and video output interface 620 third audio and video input interface 630 brother four audio and video input interface