Abstract:
A video information editing system has a field memory portion capable of storing predetermined units of digital video information, a peripheral circuit portion to make this field memory portion operate, and a video data writing circuit to rewrite video information from the field memory portion, these being added to a known video information reproducing device in the form of a video tape recorder/playback device. The system is so constructed as to access only specific video information comprising a portion of the complete original video information contained on the recording tape of the video tape recorder/playback device.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to an information editing system, especially to a television video information editing system. 
     2. Description of the Prior Art 
     A VTR (video tape recorder) and a television camera have come into wide use and are now beginning to be used as a means of preserving a visual record of the growth of members of a family, in a manner similar to the use of the conventional optical camera. 
     However, because a VRT is used to record motion or voice continuously, an incident is recorded over a span of time of some length, not being recorded at a single instant of time as in the use of the conventional camera. Therefore, it would ordinarily take some time to reproduce a single frame of recorded information from a VTR. In the latter respect, a magnetic tape is generally used in a VTR as a recording medium in which various incidents are recorded sequentially. Such a magnetic tape can record video information over a period of time ranging from 30 minutes to 6 hours per roll. Accordingly, it not be known what kind of an incident is recorded on which position of a magnetic tape without reproducing a magnetic tape by a television camera. This means that a VRT is not suitable for conveniently accessing and watching various incidents within a short time period as is the case when a photoalbum is reviewed. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     An object of the invention is to provide a system for implementing the provision of video data in a controlled format in which the recorded contents of video data produced from the use of a television camera can be known easily in a short time without reproducing all of the recorded video information. 
     Namely, the invention provides a video information editing system wherein to a basic video information reproducing circuit system are added a field memory portion capable of storing predetermined units of video information, a peripheral circuit portion for controlling the operation of the field memory portion, and a recording medium to rewrite video information from the field memory portion, the video information editing system being so constructed as to take out or access specific video information included among the original video information as recorded on the recording medium. 
     Other objects, features and advantages of the invention will appear more fully from the following detailed description thereof taken in connection with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     The single FIGURE is a schematic block diagram of a television video information editing system according to an embodiment of the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The preferred embodiments of the invention will be explained below. 
     As shown in the single FIGURE, a video information editing system is provided in which basically to an ordinary VTR are added a field memory capable of storing video information of one frame, a peripheral circuit portion for controlling the operation of the field memory (for example, an A/D converter, a circuit to control operation of a memory, etc.), and an interface means to write information from the field memory again into another recording medium (for example, a floppy disc, a magnetic tape, etc.) external to the VTR, the field memory, and the memory control circuit. 
     The operation of this editing system will now be explained. First, a magnetic tape in use for a VTR with video information already recorded thereon is reproduced by a VRT. Then, as occasion demands, video information defining one frame of video information is written into the field memory through a video circuit and an A/D converter. The content of video information of the field memory is immediately recorded or stored in an external memory device comprising a floppy disc or a magnetic tape etc. through an interface device. Necessary video pictures (i.e. one frame of video information) can be selectively reproduced or cut out by repeating the recording to the external memory device over the whole extent of the magnetic tape of the VTR. It is possible to use these pictures themselves as indexes, or to attach an index to the start of each tape by writing data from a floppy disc etc. again into the magnetic tape in use for the VTR at the beginning of the tape. 
     When using the necessary video pictures as the indexes, as shown in the single FIGURE, a frame of video information from the external memory device is input into a D/A converter through the field memory by shifting a switch between the A/D converter and the field memory as shown by broken lines to connect an output of the external memory device to an input of the field memory. The output of the D/A converter is then reproduced on a television monitor. Such an operation is applied to video pictures (cut-out video pictures as indexes) sent sequentially from the external memory device. Therefore, it is possible to view still pictures via the television monitor as indexed in a short time period, similar to the viewing of a slide or a photofilm. Of course, all of the video information would not be necessarily reproduced in this case. 
     Besides, when cutting out the video pictures as described above, a distance from the beginning of a tape on which video information is recorded at that time corresponding to the location of the frame of video information is determined (generally, a rotation number of a tape reel is used to identify the location of the frame on the tape. Namely, an output of a counter can be recorded or stored in the external memory device through the field memory thereby playing a role like a page number of a book. Therefore, in searching for particular video pictures, a switch between the counter and the field memory is shifted as shown by broken lines to input information for turning to the first address in an address index from the external memory device into a counter rotation control circuit. As a result, the video tape can be set at the corresponding position on which the desired frame of video information is found. Therefore, it is possible to monitor pictures cut off sequentially in respective TV frames of the video monitor as slide films by making the video tape set up at the corresponding positions on the tape. Thus, monitoring of the video pictures can be conveniently performed without delay when a user wants to watch pictures occurring on the tape at positions before or after the picture now being monitored. 
     Moreover, in the same way as described above, video information of corresponding to plural frames as stored in a floppy disc or other similar storage device serving as the external memory device may be written by a video circuit into the head of the video tape recorder. In this case, each frame of the video information stored in the floppy disc may be rewritten into the field memory. Then, a switch on the side of a television monitor is switched as shown by broken lines, to connect the D/A converter via a feedback line to the video circuit such that signals from the D/A converter are input into the video circuit, and the video circuit outputs signals to the video head of the VTR to be recorded on the tape by the video head. In this case, an index picture can be recorded at the beginning of the tape as if this were a book. 
     When the video information is stored in an external memory device such as a floppy disc etc. and is read out if necessary, the information should be passed through the field memory. This is because the read-out speed of video information is different between respective media. Accordingly, the speed is converted by the field memory to the appropriate speed rate. Optional pictures recorded in a video tape may be written into the field memory by a suitable known method. Furthermore, video information in the field memory may be rewritten also into the floppy disk etc. and may be reproduced by being passed through the field memory after conversion of the speed by the field memory, thereby providing only necessary video information for viewing on the television monitor without delay. 
     Moreover, video information written into the field memory is converted to be in digital values which correspond to digital data being processed in a field of an electronic computer. Therefore, the video information of the field memory can be transferred into a recording medium having a relatively large capacity such as a floppy disc or a magnetic tape etc., using a suitable known means. In addition And, as described above, by rewriting the video information of the field memory into the video head of the VTR recording on a video tape which is being currently reproduced, the contents of the field memory can be shown on a frame of a television monitor as a still picture during a desired time. Therefore, video recording can be performed at an optional position on a video tape for an optional length (namely, video recording is may be performed on a video tape repeatedly by for the necessary number of frames), by applying the same method employed in an ordinary video recording of a television picture. Furthermore, when recording video information in digital form on a floppy disc etc., because addresses are established for each bit of video information unlike a video tape, the recording can be controlled, for example, so as to record one or more pictures on a frame. 
     It will be evident that various modifications can be made to the described embodiments without departing from the scope of the present invention. 
     For example, in the above embodiment, when reproducing the video information from the recording medium, not less than two still pictures as well as one still picture can be reproduced simultaneously in a television frame, or a socalled picture-in-picture method can be applied. When reproducing plural pictures, a device can be constructed so that the necessary video information is selected by operation of a button. Instead of the above described external memory device, the video tape (magnetic tape) itself shown in the single FIGURE can be used as another recording medium. In this case, for example, a picture can be recorded on a tape in a second, or plural pictures not less than two can be recorded compactly in a second as described above. 
     In the invention, as mentioned above, because a field memory portion, a peripheral circuit portion and a recording medium are added and only specific information is taken out or accessible from this recording medium, the specific information can be selectively viewed in a video monitor with ease in a short time without reproducing all of the recorded video information.