Abstract:
A video switching apparatus has a plurality of slots each for mounting any of a first input module capable of inputting any one of a plurality of predetermined types of video signals and performing processing, content of which varies depending on the type of input video signal and a second input module capable of inputting only predetermined one type of video signal. The video switching apparatus switches and outputs video signals of a plurality of channels input to the input modules mounted to the plurality of slots. The video switching apparatus includes an input setup data memory processor, a detector, and an input setup changer.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     The present invention contains subject matter related to Japanese Patent Application JP 2006-247178 filed in the Japanese Patent Office on Sep. 12, 2006, the entire contents of which being incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an apparatus that switches and outputs input video signals on a plurality of channels. Particularly, the present invention relates to the apparatus to which various types of video signals are input. 
     2. Description of the Related Art 
     Video switchers (video switching apparatuses) are used for producing video contents. Video signals on a plurality of channels are input to a video switcher that switches and outputs those video signals and performs processing (e.g., effects such as wiping, and keying) on video at switching. 
     Although a video switcher is installed and used in a television broadcasting station, there is also a portable video switcher (for example, refer to Sony Corporation “Live Content Producer AWS-G500” issued in November 2005). A portable video switcher includes a processing unit configured to perform switching and processing on video content, an operation unit configured to perform various operations, and a display unit configured to display input video or the like, which are integrally formed. Such portable video switcher can be carried to, for example, a place where an event or the like is held and the carried portable video switcher is used to produce such video contents as introducing an activity of the event or the like. 
     Typically, video cameras of different models and a personal computer may be used to output video signals in respective places. Accordingly, a portable video switcher may need to have a configuration for composite, S-Video, DV (Digital Video), RGB and other video signals input to respective video cameras and personal computers that are used in such places. 
     For example, the video switcher described in the above Non-patent Reference (hereinafter, referred to as “related-art video switcher”) includes a plurality of slots for mounting video signal input modules in order to satisfy such requirement. Three kinds of modules (a) through (C) are prepared as the input modules capable of being mounted to those slots. 
     (a) SD module for any one of composite signal, S-Video signal and DV signal inputs; 
     (b) PC module for RGB signal input; and 
     (c) SDI module for SDI signal (serial/digital video signal based on SMPTE259M standard) input 
     Further, the related-art video switcher includes a function of collectively storing data indicating setup content carried out by a user so that later the stored data can be read and used (moreover, such data is stored on a compact memory card so that the data can also be used by another video switcher). The setup content data stored by such function includes settings for the type of input module mounted to each slot and the type of video signal input thereto. 
     However, the type of video signal input to the video switcher depends on a video camera and personal computer used as described above. Accordingly, if the past input setup with the function is used, there may be a number of cases in which another type of input module is mounted at present to the slot. Further, in the case where another video switcher uses the input setup, there may be a number of cases in which a different type of input module from the present input setup is mounted from the beginning. 
     In a video switcher of related art, in the case where an input module of a type different from the past input setup is mounted at present, processing of changing the input setup is manually performed. 
       FIG. 1  is a table showing the content of input setup change processing. Each cell of the uppermost row shows a type of input signal in the past input setup data, which has been read. Each cell of the left end column shows a type of input module mounted at present. Other cells show the content of input setup to be changed. 
     As shown in  FIG. 1 , cells highlighted with thick lines indicate that RGB and SDI signals (i.e., video signals to be input to the other modules than the SD module) are used in the past input setup, which are changed into input setup for the composite signal if the input module mounted at present is the SD module. Processing performed in the SD module is different depending on the type of input video signals. Composite signal and S-Video signal are converted into a digital component signal through luminance/color-difference separation processing and analogue/digital conversion processing. On the other hand, DV signal is converted into a digital component signal using a DV codec, and in addition, the luminance/color-difference separation processing also differs between the composite signal and S-Video signal. Accordingly, processing on the composite signal is performed in the SD module as a default (initial setting). 
     SUMMARY OF THE INVENTION 
     However, after the input setup is changed to that for the composite signal as shown with the thick lines in  FIG. 1 , S-Video signal and DV signal are still input to the SD module depending on the model of the video camera used at present. In such case, S-Video signal and DV signal may not be processed in the SD module since the input setup is composite signal. As a result, pictures of the S-Video signal and DV signal may not be displayed on a display unit. Further, S-Video signal and DV signal may not be switched and output from the video switcher. 
       FIGS. 2A and 2B  are diagrams showing an example of the above-described state. As shown in  FIG. 2A , an SDI module and a PC module are mounted to Slots A, B, respectively. Input setup data is stored while pictures of video signals output from the Slots A, B are displayed in respective areas  52 ,  53  in part of a screen of a display unit  51 . As shown in  FIG. 2B , the input setup data is read after the input modules mounted to the slots A, B are changed to SD modules respectively. Alternatively, another video switcher having SD modules respectively mounted to Slots A, B reads the input setup. In such a case, composite signal and S-Video signal are here input to the respective SD modules mounted to the slots A, B. 
     Since the type of input video signal corresponds to composite signal after the input setup change processing shown in  FIG. 1 , the input composite signal can be processed in the SD module mounted to Slot A. On the other hand, the input S-Video signal may not be processed in the SD module mounted to Slot B since the type of the input video signal does not correspond to the composite signal after the input setup change processing shown in  FIG. 1 . As a result, a picture of a video signal output from Slot A is displayed in the area  52  of the display unit  51  but a picture of a video signal output from Slot B is not displayed in the area  53  of the display unit  51  as shown in  FIG. 2B . 
     In order to display the picture of the video signal output from Slot B and to switch and output the video signal from Slot B under such state, it may have been necessary in the past to change the input setup of Slot B to the setup of S-Video signal by manually operating the operation unit. In such case, a user first checks that S-Video signal is input to the SD module mounted to Slot B based on a connection state of the SD module and video camera, or the like, and manually operates the operation unit. Therefore, such confirmation work or the like may be cumbersome for the user. 
     It is desirable to reduce cumbersome work when changing an input setup in response to a video signal input at present into a video switching apparatus including an input module such as an SD module in the above-described video switcher of related art in which content of processing varies depending on the type of the input video signal. 
     A video switching apparatus according to an embodiment of the present invention has a plurality of slots for mounting an input module for video signal input. One of a first input module and a second input module can be mounted to the slots. The first input module is capable of inputting any one of a plurality of predetermined types of video signals and performs processing, content of which varies depending on the type of input video signal. The second input module is capable of inputting only predetermined one type of video signal. The video switching apparatus switches and outputs video signals of a plurality of channels input to the input modules mounted to the plurality of slots. The video switching apparatus includes an input setup data memory processor, a detector and an input setup changer. The input setup data memory processor stores input setup data indicating a type of input module mounted to each of the slots and a type of video signal input thereto in a memory unit. The detector reads the input setup data from the memory unit and detects a slot having an input module mounted at present the type of which is not matched with the type of module indicated in the read input setup data. The input setup changer determines the type of video signal input to the first input module and causes the first input module to execute processing corresponding to the determined type of video signal upon detecting that the input module mounted at present to the slot is the first input module by the detector. 
     A video input setting method according to an embodiment of the present invention is a video signal input setting method for a video switching apparatus which has a plurality of slots for mounting an input module for video signal input. One of a first input module and a second input module can be mounted to the slots. The first input module is capable of inputting any one of a plurality of predetermined types of video signals and performs processing, content of which varies depending on the type of input video signal. The second input module is capable of inputting only predetermined one type of video signal. The video switching apparatus switches and outputs video signals of a plurality of channels input to the input modules mounted to the plurality of slots. The video signal input setting method includes the steps of: 
     storing input setup data indicating a type of input module mounted to each of the slots and a type of video signal input thereto by a controller provided in the video switching apparatus in a memory unit; 
     reading by the controller the input setup data from the memory unit and detecting a slot having an input module mounted at present the type of which is not matched with the type of module indicated by the read input setup data; and 
     determining by the controller the type of video signal input to the first input module and causing the first input module to execute processing corresponding to the determined type of video signal upon detecting that the input module mounted at present to the slot is the first input module by the detector. 
     According to the above-described embodiments of the present invention, it is possible to store the past input setup data and later use the stored data, similarly to the video switcher of related art which is described above. Further, in the case where an input module different from the input module indicated in the past input setup data is mounted at present and the mounted input module is the input module, processing of which varies depending on the type of input video signal, the type of video signal input to the input module is automatically determined so that the processing corresponding to the determined type is automatically performed. Therefore, the input setup is automatically changed corresponding to the type of input video signal at present without checking the type thereof and without manually executing a change operation. 
     A video switching apparatus according to another embodiment of the present invention has a plurality of slots for mounting an input module for video signal input. One of a first input module and a second input module can be mounted to the slots. The first input module is capable of inputting any one of a plurality of predetermined types of video signals and performs processing, content of which varies depending on the type of input video signal. The second input module is capable of inputting only predetermined one type of video signal. The video switching apparatus switches and outputs video signals of a plurality of channels input to the input modules mounted to the plurality of slots. The video switching apparatus includes an input setup data memory processor, a detector and an information display processor. The input setup data memory processor stores input setup data indicating a type of input module mounted to each of the slots and a type of video signal input thereto in a memory unit. The detector reads the input setup data from the memory unit and detects a slot having an input module mounted at present the type of which is not matched with the type of the module indicated in the read input setup data. The information display processor determines the type of video signal input to the first input module and causes information indicating the determined type of video signal to be displayed on a screen of a display unit upon detecting that the input module mounted at present to the slot is the first input module by the detector. 
     A video input setting method according to another embodiment of the present invention is a video signal input setting method for a video switching apparatus which has a plurality of slots for mounting an input module for video signal input. One of a first input module and a second input module can be mounted to the slots. The first input module is capable of inputting any one of a plurality of predetermined types of video signals and performs processing, content of which varies depending on the type of input video signal. The second input module is capable of inputting only predetermined one type of video signal. The video switching apparatus switches and outputs video signals of a plurality of channels input to the input modules mounted to the plurality of slots. The video signal input setting method includes the steps of: 
     storing input setup data indicating a type of input module mounted to each of the slots and a type of video signal input thereto in a memory unit by a controller provided in the video switching apparatus; 
     reading by the controller the input setup data from the memory unit and detecting a slot having an input module mounted at present the type of which is not matched with the type of the module indicated in the read input setup data; and 
     determining by the controller the type of video signal input to the first input module and causing information indicating the determined type of video signal to be displayed on a screen of a display unit upon detecting that the input module mounted at present in the slot is the first input module by the detector. 
     According to the above-described embodiments of the present invention, it is possible to store the past input setup data and later use the stored data, similarly to the video switcher of related art which is described above. Further, in the case where an input module different from the input module indicated in the past input setup data is mounted at present and the mounted input module is the input module, processing of which varies depending on the type of input video signal, the type of video signal input to the input module is automatically determined so that the information indicating the determined type is displayed. As a result, the user can confirm readily and instantaneously the type of the present input video signal by viewing the display and perform the operation of changing the input setup. 
     According to the video switching apparatus and the input setting of the embodiments, it is possible to use past input setup data when mounting the input module, processing of which varies depending on the type of input video signal. Further, the input setup is automatically changed corresponding to the type of the present input video signal without checking the type of input video signal at present and without manually executing a change operation. 
     According to the video switching apparatus and the input setting method of the other embodiments, it is possible to use past input setup data when monitoring the input module, processing of which varies depending on the type of input video signal. Further, the user can confirm readily and instantaneously the type of input video signal at present and perform the operation of changing the input setup. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a table showing content of input setup change processing in a video switcher according to related art. 
         FIGS. 2A and 2B  are diagrams showing an example in which an input video is not displayed on the video switcher according to related art. 
         FIG. 3  is a diagram showing the whole appearance of a video switcher to which an embodiment of the present invention is applied. 
         FIG. 4  is a diagram showing slots at the rear of the video switcher shown in  FIG. 3  and appearances of input modules mounted to those slots. 
         FIG. 5  is a diagram showing display areas for thumbnail pictures of input video signals on a screen of a liquid crystal display shown in  FIG. 3 . 
         FIG. 6  is a block diagram showing a configuration of the video switcher shown in  FIG. 3  and input modules shown in  FIG. 4 . 
         FIG. 7  is a flow chart illustrating input setup change processing performed by a main CPU indicated in  FIG. 6 . 
         FIGS. 8A to 8C  are diagrams showing an example in which an input setup is changed by the processing indicated in  FIG. 7 . 
         FIG. 9  is a flow chart illustrating the input setup change processing performed by the main CPU shown in  FIG. 6 . 
         FIGS. 10A to 10C  are diagrams showing examples in which an input setup is changed by the processing indicated in  FIG. 9 . 
         FIG. 11  is a flow chart illustrating another example of input setup change processing. 
         FIG. 12  is a diagram showing an example of an input setup change recommendation screen based on the processing of  FIG. 11 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, embodiments of the present invention are specifically explained referring to the accompanied drawings. Those embodiments are applied to a portable video switcher.  FIG. 3  is a perspective view of the whole appearance of a portable video switcher to which an embodiment of the present invention is applied. A video switcher  1  according to the embodiment has a shape somewhat larger than a notebook type personal computer. The video switcher  1  is brought to a place where an event or the like is held, for example, and is used to produce video content introducing such event by inputting video signals from a video camera and a personal computer. 
     The video switcher  1  includes an operation unit  2  configured to perform various operations such as setup, storage and retrieval of setup content, change of setup, selection of input video, switching of video, selection of effects, selection of an output mode of video and the like at a position where a keyboard is provided in a notebook type personal computer. Further, the video switcher  1  includes a liquid crystal display  3  similarly to a notebook type personal computer. 
     Three slots for mounting an input module for video signal input are provided at the rear of the video switcher  1 .  FIG. 4  is a diagram showing those slots with input modules. Any one of three types of input modules, which are an SD module  4 , a PC module  5  and an SDI module  6 , can be mounted to the three slots of Slot  1 , Slot  2  and Slot  3 , respectively. 
     The SD module  4  has terminals  4   a ,  4   b , terminals  4   c ,  4   d  to respectively input two channels of composite signals and S-Video signals, and terminals  4   e ,  4   f  to input and output two channels of DV signals, to which two channels of any one of those three types of video signals can be input. 
     The PC module  5  has terminals  5   a ,  5   b  to input two channels of RGB signals. The SDI module  6  has terminals  6   a ,  6   b  to input two channels of SDI signals (serial/digital video signal based on SMPTE259M) and a terminal  6   c  to output one channel of SDI signal. 
     The operation unit  2  shown in  FIG. 3  performs an input setup of mounting input modules from among the SD module  4 , PC module  5  and SDI module  6  to Slot  1 , Slot  2  and Slot  3  respectively, and selecting the type of video signal input thereto, as the above-described content of setup and setup change. 
     Thumbnail pictures of video signals of total six channels, which are input to the input modules mounted to Slot  1  through Slot  3  shown in  FIG. 4 , are respectively displayed on a part of the screen of the liquid crystal display  3  shown in  FIG. 3 .  FIG. 5  is a diagram showing display areas for the thumbnail pictures. Each of six areas A 1  through A 6 A displays a thumbnail picture of the input video signal on one channel. 
     It should be noted that there are other areas on the screen of the liquid display  3  than the area where such thumbnail pictures are displayed. Specifically, there is an area for displaying a picture of the video signal selected by the operation of the operation unit  2  as the video signal before switching (PGM signal) and the video signal after switching (NEXT signal) among the input video signals. Further, there is an area for displaying a menu for the operation. However, illustrations thereof are omitted since such areas are not directly related to embodiments of the present invention. 
       FIG. 6  is a block diagram showing a configuration of relevant portions of the video switcher  1  with configurations of the SD module  4 , PC module  5  and SDI module  6  shown in  FIG. 4  and a connection relation between the input modules mounted to Slot  1  through Slot  3  and the video switcher  1 . 
     The SD module  4  includes a block  4 - 1  configured to process composite signal, S-Video signal, or DV signal input from the terminal  4   a ,  4   c  or  4   e  and a block  4 - 2  configured to process composite signal, S-Video signal or DV signal input from the terminal  4   b ,  4   d  or  4   f . Also, the PC module  5  includes a block  5 - 1  configured to process RGB signal input from the terminal  5   a  and a block  5 - 2  configured to process RGB signal input from the terminal  5   b . Further, the SDI module  6  includes a block  6 - 1  configured to process SDI signal input from the terminal  6   a  and a block  6 - 2  configured to process SDI signal input from the terminal  6   b . Since the two blocks in the respective input modules have internal configurations similar to each other, the configuration of one of the two blocks is shown as a representative. 
     Composite signal input from the terminal  4   a  to the SD module  4  and S-Video signal input from the terminal  4   c  to the SD module  4  are supplied to an A/D converter  10 . The A/D converter  10  converts the input video signal into a digital component signal (D1 signal) through synchronization detection processing, luminance/color-difference separation processing and analogue/digital conversion processing and supplies the converted D1 signal to a frame synchronizer and resizer  11 . 
     The DV signal input from the terminal  4   e  to the SD module  4  is sent to a DV codec  12 . The DV codec  12  converts the input DV signal into a D1 signal through synchronization detection processing and decoding processing and supplies the converted D1 signal to the frame synchronizer and resizer  11 . 
     The frame synchronizer and resizer  11  synchronizes the D1 signals received from the A/D converter  10  and the DV codec  12  with a reference synchronization signal in the video switcher  1 . Subsequently, the frame synchronizer and resizer  11  converts a picture size of the signal into 1,280×1,024 pixels (SVGA) that is a unified picture size in processing performed in the video switcher  1 . 
     The D1 signal having the picture size converted by the frame synchronizer and resizer  11  is supplied from the frame synchronizer and resizer  11  to a cross point unit  21  in the video switcher  1  and is also supplied from the frame synchronizer and resizer  11  to a picture converter  30  in the video switcher  1  through a local CPU  13 . 
     Composite signal, S-Video signal or DV signal input from the terminal  4   b ,  4   d  or  4   f  to the SD module  4  is also converted into a D1 signal of 1,280×1,020 pixels in the same manner and is supplied to the cross point unit  21  and the picture converter  30  in the video switcher  1 . 
     The content of processing in the SD module  4  varies depending on the type of input video signal. Specifically, input composite signal or S-Video signal is converted into D1 signal in the A/D converted  10 . On the other hand, input DV signal is converted into D1 signal in the DV codec  12 . Moreover, the luminance/color difference separation processing in the A/D converter  10  is also different between composite signal and S-Video signal. The processing to be performed in the SD module  4  is determined in accordance with a type of video signal by a main CPU  31  included in the video switcher  1  depending on a slot among Slot  1  through Slot  3  to which the SD module  4  is mounted, as later described. 
     Analogue RGB signal input from the terminal  5   a  to the PC module  5  is converted into a digital RGB signal of 1,280×1,024 pixels by an A/D converter  14  and a frame synchronizer and resizer  15 , and the converted digital RGB signal is supplied from the frame synchronizer and resizer  15  to the cross point unit  21  in the video switcher  1 . Further, the converted digital RGB signal is also supplied from the frame synchronizer and resizer  15  to the picture converter  30  in the video switcher  1  through a local CPU  16 . 
     The analogue RGB signal input from the terminal  5   b  to the PC module  5  is also converted into a digital RGB signal of 1,280×1,024 pixels in the same manner and is supplied to the cross point unit  21  and the picture converter  30  in the video switcher  1 . 
     The processing to be performed in the PC module  5  is also determined in accordance with a type of video signal by a main CPU  31  included in the video switcher  1  depending on a slot among Slot  1  through Slot  3  to which the PC module  5  is mounted. 
     SDI signal input from the terminal  6   a  to the SDI module  6  is converted into D1 signal by a S/P (Serial/Parallel) converter  17 . Subsequently, the resultant signal is converted into a signal having the picture size of 1,280×1,024 pixels by a frame synchronizer and resizer  18 , and is supplied to the cross point unit  21  in the video switcher  1  from the frame synchronizer and resizer  18 . Further, the signal is supplied from the frame synchronizer and resizer  18  to the picture converter  30  in the video switcher  1  through a local CPU  19 . 
     SDI signal input from the terminal  6   b  to the SDI module  6  is also converted into the D1 signal of 1,280×1,024 pixels in the same manner and is supplied to the cross point unit  21  and the picture converter  30  in the video switcher  1 . 
     The processing to be performed in the SDI module  6  is also determined in accordance with a type of video signal by a main CPU  31  included in the video switcher  1  depending on a slot to which the SDI module  6  is mounted among Slot  1  through Slot  3 . 
     The cross point unit  21  in the video switcher  1  receives the digital video signals of 1,280×1,024 pixels of maximum six channels input from Slot  1  through Slot  3 . The cross point unit  21  selects a video signal of one channel as the video signal before switching (PGM input), video signal after switching (NEXT input), and signal for keying, respectively. The cross point unit selects those signals by the control of the main CPU  31  based on the operation of selecting input video performed at the operation unit  2  ( FIG. 3 ), and sends the selected video signals to a switcher/effects unit  22 . 
     The switcher/effects unit  22  performs video switching and video processing (effects such as wipe, and keying) by the control of the main CPU  31  based on the video switching operation and effect selection operation using the operation unit  2 . 
     The video signal (PGM output) formed through the switching and processing performed at the switcher/effects unit  22  is converted into D1 signal or digital RGB signal at a resizer  23 . Further, the resultant signal is converted into composite signal or S-Video signal or analogue RGB signal at D/A converters  24  and  25  both by the control of the main CPU  31  based on the video output mode selection operation performed at the operation unit  2 . Subsequently, the converted signals are output from video output terminals  26  through  28  of the video switcher  1 . In addition, PGM output from the switcher/effects unit  22  and D1 signal from the resizer  23  are also returned to the DV codec  12  in the SD module  4  and the P/S converter  20  in the SDI module  6  through a selector  29  by the control of the main CPU  31  in response to the video output mode selection operation. As a result, returned signals are output as D1 signal and SDI signal from the terminals  4   e  and  4   f  of the SD module  4  and the terminal  6   c  of the SDI module  6 , respectively. 
     The picture converter  30  compresses a digital video signal of 1,280×1,024 pixels of maximum six channels input from Slot  1  through Slot  3  into the video signal for thumbnail display and supplies the compressed video signal to the main CPU  31 . 
     The main CPU  31  causes the thumbnail picture of each channel to be displayed in each of the areas A 1  through A 6  of the liquid crystal display  3  using the compressed video signal as shown in  FIG. 5 . Further, the main CPU causes the thumbnail pictures of the selected channels as the PGM input and NEXT input to be displayed in other areas of the liquid crystal display  3 . 
     It should be noted that the video switcher  1  further includes a slot for mounting a recording device such as a compact memory card, although not illustrated in the figure. 
     Next, input setup processing performed in the video switcher  1  is explained. As described above, the operation unit  2  is capable of performing not only the setup of the video switcher  1  but also the storage and retrieval of the setup content. Specifically, according to such function, data showing the content of setup performed by the user is collectively stored in a memory in the main CPU  31  and the stored data is later read and used. Further, the data may be stored in a compact memory card so that another video switcher can use the data. The main CPU  31  controls each unit included in the video switcher  1  and an input module mounted to each of Slot  1  through Slot  3  based on the setup content data retrieved. 
     The content of setup performed with the above-described function includes such input setup as follows. Specifically, the input setup includes determining: the type of input module mounted to each of Slot  1  through Slot  3 ; the types of video signals respectively input to the two blocks of each input module; and areas for the thumbnail pictures of the video signals of six channels output from Slot  1  through Slot  3  respectively displayed in the areas A 1  through A 6  (as shown in  FIG. 5 ) of the liquid crystal display  3 . 
     It should be noted that first blocks (block  4 - 1  in the SD module  4 , block  5 - 1  in the PC module  5 , and block  6 - 1  in the SDI module  6 ) in the respective input modules mounted to Slot  1 , Slot  2  and Slot  3  are hereinafter referred to as “Slot  1 - 1 ”, “Slot  2 - 1 ” and “Slot  3 - 1 ”. Further, second blocks (block  4 - 2  in the SD module  4 , block  5 - 2  in the PC module  5 , and block  6 - 2  in the SDI module  6 ) in the respective input modules mounted are referred to as “Slot  1 - 2 ”, “Slot  2 - 2 ” and “Slot  3 - 2 ”. When referring to respective blocks in this manner, the above-described input setup is expressed as follows. Specifically, the input setup includes determining: the type of input module mounted to each slot of Slot  1  through Slot  3 ; the types of video signals respectively input to Slots  1 - 1 ,  1 - 2 ,  2 - 1 ,  2 - 2 ,  3 - 1  and  3 - 2 ; and areas for the thumbnail pictures of the video signals output from the Slots  1 - 1 ,  1 - 2 ,  2 - 1 ,  2 - 2 ,  3 - 1  and  3 - 2  respectively displayed in the areas A 1  through A 6  (as shown in  FIG. 5 ) of the liquid crystal display  3 . 
     However, if input setup of the past is used with such function, there may be a number of cases in which the input modules mounted to Slot  1  through Slot  3  have been changed to other types of input modules depending on a video camera and personal computer being used, since the type of input video signal to the video switcher  1  is dependent on the video camera and personal computer used at present. In addition, when another video switcher uses the input setup, there are a number of cases in which an input module having input setup originally different from the input setup is mounted. 
     Therefore, the main CPU  31  executes input setup change processing as shown in  FIG. 7  and input setup change processing as shown in  FIG. 9 , on the input setup retrieved by the above-described function. 
     According to input setup change processing indicated in  FIG. 7 , input setup data is read (step S 1 ). Subsequently, the type of input module mounted at present to each of Slot  1  through Slot  3  is detected based on identification information of each type of input module that is stored in the respective local CPU  13 ,  16  and  19  (as shown in  FIG. 6 ) in the SD module  4 , PC module  5  and SDI module  6  (step S 2 ). 
     Subsequently, it is determined for each of Slot  1  through Slot  3  whether the type of input module indicated in the read input setup data corresponds to the type of the input module mounted at present (step S 3 ). 
     If there is a slot to which is mounted an input module different from a module indicated in input setup data, it is determined whether the input module mounted at present to the slot is a PC module  5  or SDI module  6  (step S 4 ). If the result is NO (the input module mounted at present is an SD module  4 ), a synchronization detection result is obtained at the A/D converter  10  or DV codec  12  in the respective blocks of  4 - 1  and  4 - 2  in the SD module  4  (shown in  FIG. 6 ) through the local CPU  13 . Subsequently, it is determined based on the synchronization detection result which type of video signal is input to the respective blocks of  4 - 1  and  4 - 2  in the SD module  4  among composite signal, S-Video signal and DV signal (step S 5 ). 
     Subsequently, the input setup is changed so that the processing corresponding to the determined type of video signal is performed at respective blocks in the input module of the slot (step S 6 ), and the processing is ended. 
     If the result is YES at step S 4 , video signals input to the PC module  5  and SDI module  6  are RGB signal and SDI signal respectively. Therefore, input setup is changed so that the input module of the slot in the case of the PC module  5  performs processing corresponding to RGB signal (step S 7 ). Similarly, input setup is changed so that the input module of the slot in the case of the SDI module  6  performs processing corresponding to SDI signal (step S 7 ), and the processing is ended. 
     In the case where the result is YES at step S 3 , processing is ended without changing input setup since the input module mounted to each of Slot  1  through Slot  3  can process the input video signal without any change. 
       FIGS. 8A ,  8 B and  8 C are diagrams showing an example in which input setup is changed through the input setup change processing indicated in  FIG. 7 . In this example, the PC module  5  is mounted to Slot  1  as shown in  FIG. 8A  and the input setup is stored in a state of a picture of the video signal from Slot  1  being displayed in the area A 1  (as shown in  FIG. 5 ) of the liquid crystal display  3 . Further, as shown in  FIG. 8B , the input setup is read after the input module mounted to Slot  1  is exchanged with the SD module  4 , or the input setup is read by another video switcher having the SD module  4  mounted to Slot  1 . In such a case, S-Video signal is input to the block  4 - 1  of the SD module  4 . In the figures, Slot  1 - 1  indicates a portion corresponding to the first block of the input module mounted to Slot  1  as described above.  FIGS. 8A and 8B  illustrate the same states as those of slot B shown in  FIGS. 2A and 2B . 
     Here, the processing in  FIG. 7  is performed from step S 3  to steps S 4  and S 5 . The video signal input to the block  4 - 1  of the SD module  4  is automatically determined as S-Video signal at step S 5 . Afterward, the input setup is automatically changed at step S 6  so that the processing corresponding to S-Video signal is performed at the block  4 - 1  of the SD module  4 . More specifically, input setup is automatically changed corresponding to the type of video signal input at present. Accordingly, there is no need for the user to confirm from the state of connection between the SD module  4  and video camera or the like that S-Video signal is input to the block  4 - 1  of the SD module  4  mounted to the slot of Slot  1 . Further, there is no need to manually change the input setup of Slot  1 - 1  to S-Video signal by operating the operation unit  2 . 
     Accordingly, since the type of input video signal matches S-Video signal obtained through the input setup change processing shown in  FIG. 7 , input S-Video signal can be processed in the block  4 - 1  of the SD module  4 . As a result, as shown in  FIG. 8C , a thumbnail picture of S-Video signal output from Slot  1 - 1  is displayed in the area A 1  of the liquid crystal display  3  and the S-Video signal can be switched and output. 
     As described above, the video switcher  1  can use the past input setup and can automatically change input setup through the input setup change processing indicated in  FIG. 7  corresponding to the type of video signal input at present. 
     In the input setup change processing indicated in  FIG. 9 , the same processing (steps S 11  through S 13 ) as that of steps S 1  through S 3  of the input setup change processing indicated in  FIG. 7  is performed. Subsequently, if it is determined that there is a slot to which is mounted an input module different from a module indicated in input setup data, loop processing of steps S 14  through S 19  is performed on each slot in the numerical order of the above-described Slots  1 - 1 ,  1 - 2 ,  2 - 1 ,  2 - 2 ,  3 - 1  and  3 - 2 . 
     The processing performed on each slot in the loop processing is as follows. First, it is searched based on the above-described identification information on each type of input module whether the same type of input module as the input module, which has been mounted to the slot according to the input setup data read at step S 11 , is mounted to another slot at present (step S 15 ). 
     If the same type of input module is found, it is determined whether the type of input module indicated in the input setup data read at step S 11  is the type of input module mounted at present to the above-described “another slot” to which the same type of input module is mounted (step S 16 ). In the case where the result is NO, it is determined whether the input setup is already changed at subsequent step S 18  with respect to the above-described “another slot” (step S 17 ). 
     If the result is NO, input setup is changed so that the video signal output from the above-described “another slot” is alternatively displayed in an area where a picture of the video signal, which is output from the slot and determined to be different at step S 13  according to the input setup data read at step S 11 , has been displayed in the areas A 1  through A 6  (as shown in  FIG. 5 ) of the liquid crystal display  3  (step S 18 ). 
     The processing is ended after completing the loop processing. The processing is ended without further processing: in the case where the result is YES at step S 13 ; in the case where the result is NO at step S 15 ; and in the case where the result is YES at step S 16  or step S 17 . 
       FIGS. 10A ,  10 B and  10 C are diagrams showing an example in which input setup is changed through the input setup change processing indicated in  FIG. 9 . As shown in  FIG. 10A , an SDI module  6 , PC module  5  and SD module  4  are respectively mounted to Slot  1 , Slot  2  and Slot  3 , and composite signals are input to Slots  3 - 1  and  3 - 2  respectively; and thumbnail pictures of video signals output from the Slots  1 - 1 ,  1 - 2 ,  2 - 1 ,  2 - 2 ,  3 - 1  and  3 - 2  are displayed in the areas A 1 , A 5 , A 6 , A 2 , A 3  and A 4  of the liquid crystal display  3 , respectively. Such a state is stored as an input setup. Further, as shown in  FIG. 10B , the above-described input setup is read after the input modules mounted to Slot  1 , Slot  2  and Slot  3  are respectively changed to the PC module  5 , SD module  4 , and SDI module  6 . Alternatively, the input setup is read by another video switcher having the PC module  5 , SD module  4 , and SDI module  6  respectively mounted to Slot  1 , Slot  2  and Slot  3 . In this state, composite signals are respectively input to the blocks  4 - 1  and  4 - 2  of the SD module  4 . 
     In the state shown in  FIG. 10B , the thumbnail pictures are displayed respectively in the areas of A 1  through A 6  by the above-described input setup change processing indicated in  FIG. 7 . However, correspondence between thumbnail pictures of video signals and displayed areas, shown in  FIG. 10B , becomes different from that shown in  FIG. 10A . 
     In such a case, the processing goes from step S 13  to the loop processing of steps S 14  through S 19  in the processing indicated in  FIG. 9 . As a result, as shown in  FIG. 10C , the correspondence between the video signals and the areas A 1  through A 6  is changed by the loop processing so that the correspondence becomes the same as that shown in  FIG. 10A . 
     Accordingly, the correspondence between the thumbnail pictures of video signals displayed and areas is automatically maintained to be constant. 
     Next, another example of the input setup change processing performed by the main CPU  31  will be explained with reference to  FIG. 11 . According to the input setup change processing indicated in  FIG. 11 , the same processing (steps S 21  through S 25 ) as steps S 1  through S 5  of the input setup change processing indicated in  FIG. 7  is first performed. After the result is YES at step S 24  and after the processing of step S 25  is performed, processing (steps S 26  and S 27 ) equivalent to that of steps S 15  and S 16  in the input setup change processing indicated in  FIG. 9  is performed on the slot determined to be a slot having an input module different from the module indicated in input setup data at step S 23 . 
     Further, based on the processing performed at steps S 26  and S 27  and a result of the type of video signal determined at step S 25 , such an input setup change recommendation screen as exemplarily shown in  FIG. 12  is displayed on the liquid crystal display  3  (step S 28 ). Then, the process is ended. 
     As shown in  FIG. 12 , numerals  1  through  6  shown in vertical direction at the left end of the input setup change recommendation screen indicates the areas A 1  through A 6  (shown in  FIG. 5 ) on the liquid crystal display  3 . The input setup change recommendation screen recommends the change of the input setup to maintain the correspondence between the types of video signals and the respective areas A 1  through A 6  of the liquid crystal display  3  to be constant as exemplarily shown in  FIGS. 10A to 10C  based on the result of the processing at steps S 26  and S 27 . Further, recommendation for changing the input setup into the determined type of video signal is displayed with respect to the slot, the type of video signal of which is determined at step S 25 .  FIG. 12  shows a state in which a thumbnail picture of video signal output from Slot  1 - 2  is displayed in the area A 1  and the recommendation for changing the input setup of Slot  1 - 2  into DV signal is displayed. 
     Referring to the displayed input setup change recommendation screen as shown in  FIG. 12 , the user can confirm easily and instantaneously which thumbnail picture of a video signal output from a slot should be displayed in which area in order to constantly maintain the correspondence between the types of video signals and the areas A 1  through A 6 . Hence, the user can perform the operation of changing the input setup using the operation unit  2  so that the thumbnail picture of the video signal output from Slot  1 - 2  is displayed in the area A 1 . In addition, the user can confirm easily and instantaneously from the above display that DV signal is input to the block  4 - 2  of the SD module  4  mounted to Slot  1  without confirmation based on the connection state between the SD module  4  and the video camera, or the like, and the operation of changing the input setup of Slot  1 - 2  into DV signal can be performed using the operation unit  2 . 
     If the user changes the input setup as recommended in the display shown in  FIG. 12 , Slot  1 - 2  is excluded from the slots to which the recommendation is displayed in the input setup change recommendation screen with respect to the areas A 2  through A 5  other than the area A 1 . Such case is equivalent to the case in which the result is YES at step S 17  indicated in  FIG. 9 . 
     It should be noted that the recommendation screen is displayed in the input setup change processing indicated in  FIG. 11  upon executing both the determination of the type of video signal by the input setup change processing of  FIG. 7  and the search of an alternative slot by the input setup change processing of  FIG. 9 . However, embodiments of the present invention are not limited thereto, and the determination of the type of video signal by the input setup change processing of  FIG. 7  alone may be performed such that the recommendation for changing the input setup to the determined type of video signal is displayed. 
     Further, in the above-described examples, embodiments of the present invention are applied to a video switcher to which is mounted an SD module capable of inputting any one of video signals among composite signal, S-Video signal and DV signal. However, embodiments of the present invention can be applied to any video switching apparatuses to which is mounted an input module performing processing which is different depending on the type of input video signal. 
     It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.