JP2008028607A - Imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging device which picks up an image at, for example, an imaging frame rate 20p, converts the image to an output frame rate 60p, and outputs the image, wherein a video sequence and a time code sequence are coincident in phase with each other while continuity of time codes is held even when the imaging frame rate is varied. <P>SOLUTION: The imaging frame rate when varied from 20p to 24p is varied from 20p to 24p temporarily via 30p. A period wherein an image is picked up at 30p is determined based upon the length of a first video sequence as a repetition unit when an imaging means performs frame rate conversion from 20p to 60p, the length of a second video sequence as a repetition unit when the imaging means performs frame rate conversion from 24p to 60p, and the frame value of a time code at the head of the first video sequence right before the frame rate change. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an imaging apparatus that realizes an imaging effect equivalent to that of a film camera, and more specifically, in the digital cinema production field in which video production equivalent to that of a film cinema system is performed by importing and editing into a nonlinear editor system. The present invention relates to an imaging apparatus to be used.

  In conventional movie production using film, 24 images are recorded per second and 24 images are reproduced per second. Furthermore, in order to produce a special effect, for example, 12 images are recorded per second and 24 images are reproduced per second, thereby realizing a double speed quick motion. In addition, for example, 48 images are recorded per second and 24 images are reproduced per second, thereby realizing a half-speed slow motion. Changing the number of recordings per second was done by changing the film rotation speed of the film camera during recording.

  In recent years, proposals (digital cinema production) have been made to replace movie production (film cinema production), which was conventionally performed with a film camera, with a video camera. Examples of digital cinema production equipment will be described below. In conventional video cameras, a method of recording 60 video signals per second on a video tape was used, but in digital cinema production equipment, imaging was performed at 24 images per second and 60 video signals per second. The frame rate is converted into a video tape and recorded on a video tape, and then converted into 24 video signals per second during reproduction. By doing so, it was possible to provide a high-quality system at low cost by using the signal processing circuit of the conventional video camera as it is. Furthermore, in special effect shooting, imaging is performed at 12 or 48 frames per second, the frame rate is converted to 60 video signals per second, and recording is performed on a video tape. After using a device that extracts an effective frame, it is converted into 24 video signals per second. By doing so, it was possible to realize special effect shooting even in a video camera in which it was difficult to change the recording speed.

  Next, the configuration of an imaging device used in conventional digital cinema production will be described. FIG. 3 is a block diagram of an imaging apparatus used in conventional digital cinema production. The imaging unit 31 performs imaging at an imaging frame rate corresponding to the frame rate change information FRp3 from the system control unit 32, performs conversion processing to a predetermined frame rate, and outputs the result. The CCD driving means 35 sets the imaging frame rate according to the frame rate change information FRp3 from the system control unit 32, drives the CCD at the imaging frame rate, and outputs a video signal. The frame rate conversion means 36 receives the video signal output from the CCD drive means 35, performs a frame rate conversion process to an output frame rate using a memory, and outputs it. When the user is instructed to change the frame rate by menu setting or button operation, the operation unit 34 outputs the frame rate change operation information OP3 to the system control unit 32.

  Next, frame rate conversion and frame rate change used in this specification will be described. Converting the first frame rate video to the second frame rate by the frame rate conversion means is called frame rate conversion, and changing the first frame rate input to the frame rate conversion means is called frame rate change. For example, a frame rate conversion is to convert a 24p (having 24 progressive images per second) video signal output from the CCD driving means into a 60p (having 60 progressive images per second) video signal. Changing the frame rate output from the CCD drive means from 24p to 20p is a frame rate change.

  Next, a frame rate conversion method in a conventional imaging apparatus will be described by taking conversion from a 24p video signal to a 60p video signal as an example.

  FIG. 4 simply shows a frame rate conversion method from a 24p video signal to a 60p video signal. In this method, the frame rate conversion means has three memories capable of storing video signals, and holds a write memory number indicating a memory number to be written and a read memory number indicating a memory number to be read. These are used to realize frame rate conversion. The 24p video signal is, for example, a video signal input from the CCD driving unit to the frame rate conversion unit, and one of the three video signals stored in the memory is updated every 1/24 seconds.

  The write memory number is set to a value that circulates in synchronization with the 24p video signal every 1/24 second, which is the update unit of the video signal before frame rate conversion. In this case, since the number of mounted memories is 3, a value is set as 1-2-3-1-2-3. The memory 1 stores a 24p video signal input when the write memory number is 1. The memory 2 stores the 24p video signal input when the write memory number is the value 2. The memory 3 stores the 24p video signal input when the write memory number is the value 3.

  The read memory number is set to a value that circulates in synchronization with the 60p video signal every 1/60 seconds, which is the update unit of the video signal after frame rate conversion. However, if the memory to be read becomes the same as the memory to be written when it is updated, that is, if the write memory number and the read memory number are the same, it is controlled not to update. The video signal read from the memory indicated by the read memory number is output from the frame rate conversion means as a 60p video signal.

  In this case, for example, the converted 60p video signals VF21 and VF22 have the same video information. The 60p video signals VF23, VF24, and VF25 have the same video information. In this way, two or three 60p video signals converted from the 24p video signal have the same video information, and are repeated every five video frames.

  When the converted 60p video signal is converted into a 60i video signal (having 60 interlaced videos per second), the 60p video signals VF21 and VF22 are converted into the first field VF26 and the second field VF27 of the 60i video signal. Is converted to As described above, two video frames of the 60p video signal are converted into one video frame of the 60i video signal. Therefore, one video frame of the 60i video signal is 1/30 seconds and is repeated every five video frames. As described above, a repetition unit when converting the frame rate from the frame rate before conversion to the frame rate after conversion is called one video sequence. The length of the video sequence of the 60i video signal is 5 video frames. In addition, since the 60p video signal may be converted into a 60i video signal and distributed, the length of the video sequence of the 60p video signal is as long as 5 video frames of the 60i video signal in order to obtain compatibility. The total is 10 video frames.

  Further, an example of frame rate conversion from a 20p video signal to a 60p video signal will be described.

  FIG. 5 simply shows a frame rate conversion method from a 20p video signal to a 60p video signal. Similar to FIG. 4, the length of the video sequence of the converted 60p video signal is 6 video frames of the 60p video signal.

  Next, a case where the converted video signal is inversely converted to a frame rate before conversion or converted to another frame rate will be described. The video signal that has been edited and can be distributed may be distributed after being converted to a frame rate different from the frame rate used at the time of editing. For example, a 60p video signal may be distributed as it is, or may be distributed after being converted into a 24p video signal for movie screening. In addition, there are cases in which a 60i video signal is converted and distributed for television broadcasting. When the frame rate is converted in this way, the processing can be performed more easily when the time code is used than when the frame rate is converted using only the video signal.

  FIG. 6 is an explanatory diagram when the converted 60p video signal is inversely converted into a 24p video signal. Here, since the time code of the 30-frame system is normally used even in the 60p video signal, the possible values are from 00:00:00 to 23: 59: 59.29 frames. Therefore, as shown in the figure, the same time code is generated for every two consecutive frames in the 60p video signal. Hereinafter, two frames to which the same time code is assigned in the 60p video signal are referred to as a first half video frame and a second half video frame. In the figure, for convenience, only the frame value of the time code is shown. Further, the description of the signal delay that occurs during frame rate conversion is omitted.

  When reverse conversion of the frame rate using only the video signal, that is, conversion to the original 24p video signal, one video frame of the 60p video signal and one video frame after one or two frames are the same. In order to determine whether or not, it is necessary to prepare a memory for storing one video frame, or to repeatedly perform the comparison operation using a small amount of memory.

  Here, when a time code is assigned so that the time code of the first frame of the video sequence in the 60p video signal is a multiple of 5, the frame with the remainder obtained by dividing the time code value by 5 is the first half video frame. The second half video frame is the same, that is, the first half video frame is a frame that should be valid after conversion (effective frame), and the second half video frame is a frame that is not used for conversion (invalid frame) without complicated calculations. It can be judged. Similarly, when the remainder is 1, the first half video frame is a valid frame and the second half video frame is an invalid frame, and when the remainder is 2, the first half video frame is an invalid frame and the second half video frame is a valid frame and the remainder is 3. When the first half video frame is an invalid frame, the second half video frame is a valid frame, and when the remainder is 4, it can be determined that both the first half video frame and the second half video frame are invalid frames. In the above description, the first video frame of the video frames having the same video information is the effective frame. However, the last video frame may be the effective frame, or the second video frame may be the effective frame.

  A sequence of time codes associated with a video signal so that the video sequence can be specified as described above is called a time code sequence. In the case of FIG. 6, the time code sequence is 0-1-2-3-4, 5-6-7-8-9, (the remainder after dividing by 5 is followed by 0-1-2-3-4). The length of the time code sequence is 5TC frames. A time code frame is referred to as a TC frame in order to distinguish it from a video frame. For example, since a time code is given as described above in a 60p video signal, 10 video frames correspond to 5TC frames.

  As a conventional imaging device that performs the frame rate conversion as described above, there is one described in Patent Document 1. This is to obtain an image pickup effect equivalent to that of a film camera with a video camera, and particularly has a feature that the frame rate can be freely converted with respect to image creation unique to the film camera.

  An imaging apparatus that converts a frame rate and that can change the frame rate is disclosed in Patent Document 2. This is characterized in that the frame rate during shooting can be changed in accordance with preset frame rate change information.

  An apparatus for setting a time code for a video signal whose frame rate has been converted is described in Patent Document 3. This is because the time code of a plurality of systems, for example, the time code of 24 frame system, 30 frame system and 25 frame system is recorded at the time of recording, and an appropriate time code system can be selected from the time code systems recorded at the time of reproduction. There is.

  Along with recent digitization, a technique has been adopted in which captured video signals are captured and edited by a non-linear editor. The time code is recorded in association with the video signal at the time of shooting, and is used for specifying the start and end positions of capture and the start and end positions of editing.

As the time code stepping method, there are a reclan method that advances only during recording and does not advance when recording is stopped, and a free-run method that advances regardless of whether recording is stopped or not. The Reclan system has a feature that even when a plurality of scenes are photographed, a continuous time code is recorded regardless of the middle of a scene or a scene change. On the other hand, in the free run system, the continuity of the time code is impaired at the scene change point, but the time code recorded in each scene can be used as the recording time. This time code stepping method is properly used depending on the production form.
Japanese Patent Application Laid-Open No. 2002-152569 JP 2005-136754 A JP 2005-39713 A

  The conditions required for the imaging apparatus for production in a digital cinema will be described below.

  As a first condition, the continuity of time code will be described.

  When capturing a video signal with a nonlinear editor, it may be required to input a continuous time code to the nonlinear editor together with the video signal. The non-linear editor may determine the end of recording or importing into the same file from the continuity of the time code. If the time code is discontinuous, the nonlinear editor detects the input of the discontinuous time code, determines that the shooting scene has changed, and saves it as a separate file, or determines that the input is abnormal. The import operation is stopped. In other words, even though the operator of the nonlinear editor intended to save the video signal of a scene as a single file, it was saved as multiple files, and the efficiency of the editing process, which is the subsequent process, was reduced. It will decline. Or, although automatic capture is intended, there is a problem that the capture operation is interrupted and the capture operation must be performed again.

  As the second condition, the phase matching between the video sequence and the time code sequence will be described.

  It is desirable that the video sequence and the time code sequence are made to coincide with each other with respect to the importing operation and editing operation into the non-linear editor. That is, it is required that the phase of the video code sequence of the video signal output from the imaging apparatus and the time code sequence of the time code output from the imaging apparatus match. This is because when the completed video signal is re-converted to an arbitrary frame rate for distribution as well as the frame rate used at the time of editing, it can be easily converted by using a time code.

  As a third condition, a description will be given of time code synchronization during multi-camera shooting.

  Regarding the operation when the time code generated outside the imaging apparatus is input to the imaging apparatus, the time code output together with the video signal by the imaging apparatus is required to match (synchronize) with the time code input from the outside. . This is because, when shooting using a plurality of imaging devices (hereinafter referred to as multi-camera shooting), the time codes of the respective imaging devices are made to coincide with each other, and a plurality of materials shot with a plurality of imaging devices in the editing process are recorded. This is to improve the efficiency of the editing work by making it possible to arrange them in time series.

  In the case of multi-camera shooting, the time code of the shot material is generally discontinuous every time the scene changes. This is to save each scene as a separate file when importing it into the nonlinear editor so as to improve the efficiency of the editing process as a subsequent process. Therefore, the first condition and the third condition are not obtained simultaneously.

  However, the conventional imaging apparatus has a problem that when the frame rate is changed, the first condition and the second condition cannot be made compatible. Hereinafter, a description will be given with reference to FIGS.

  FIG. 7 is an explanatory diagram when the frame rate is changed from 20p to 24p during the frame rate conversion from the 20p video signal to the 60p video signal. The frame rate is changed from 20p to 24p at the timing of FRP20p24p1, and is reflected in the 60p video signal at the timing of FRA20p24p1. The video sequence before the frame rate change is VS20p1, and the time code sequence is TS20p1 because the remainder of dividing the time code value by 3 is 0, so the phase of the video sequence and the time code sequence is the same. . On the other hand, the video sequence after the frame rate change is VS24p1, and the time code sequence starts from a frame with a remainder obtained by dividing the time code value by 5, so that it becomes TS24p1 delayed by 2TC frames from the video sequence. The phase of the code sequence does not match. As described above, when the frame rate is changed between frame rates having different video sequence lengths, the phases of the video sequence and the time code sequence cannot be matched after the frame rate is changed. Accordingly, in FIG. 7, the first condition can be satisfied, but the second condition cannot be satisfied.

  In this case, there is a method of shifting the phase of the time code sequence in order to make the phases of the video sequence and the time code sequence coincide after changing the frame rate. FIG. 8 shows that when the frame rate is changed from 20p to 24p during the frame rate conversion from the 20p video signal to the 60p video signal, the phases of the video sequence and the time code sequence are made to coincide after the frame rate is changed. It is explanatory drawing of the method of shifting the phase of a time code sequence. The difference from FIG. 7 is that the time code of the point TC24p2 is corrected so that the phase matches the phase of the video sequence VS24p2 after the frame rate change. In the time code sequence for the 24p video signal, since the remainder divided by 5 starts from 0, the time code that should originally be the value 3 at the point TC24p2 is corrected to the value 5. The time code to be corrected may be 0, but the value 5 having the smallest correction error is selected. In this way, the phases of the video sequence VS24p2 and the time code sequence TS24p2 after the frame rate change can be matched. However, the time code becomes discontinuous at 0-1-2-5-6-7 and the point TC24p2. Accordingly, in FIG. 8, the second condition can be satisfied, but the first condition cannot be satisfied.

  Next, a case where the frame rate is changed when the phase of the video sequence and the time code sequence is arbitrary before the frame rate is changed will be described.

  FIG. 9 shows that the frame rate is changed from 20p to 24p when the frame rate conversion from the 20p video signal to the 60p video signal is in progress and the phase of the video sequence before the frame rate change and the time code sequence is arbitrary. It is explanatory drawing in the case. Note that the signal delay that occurs during frame rate conversion is not shown. The frame rate is changed from 20p to 24p at the timing of FRP20p24p5, and is reflected in the 60p video signal at the timing of FRA20p24p5. The video sequence before the frame rate change is VS20p5, and the video sequence after the frame rate change is VS24p5. Since the phase of the time code sequence before the frame rate change is arbitrary, the time code sequence after the frame rate change may have five phases from TS24p51 to TS24p55. In this case, when the phase of the time code sequence before conversion is the time code (pattern 3) in the figure, the time code sequence after the frame rate change matches the video sequence, but there are four other cases The time code sequence after changing the frame rate does not match the video sequence. Accordingly, in FIG. 9, the first condition can be satisfied, but the second condition is not always satisfied.

  In FIG. 9, when the method of shifting the phase of the time code sequence so as to match the phase of the video sequence and the time code sequence after the frame rate is changed, the time code is changed except for the time code (pattern 3) in the figure. Since the discontinuity is clearly the same as the description of FIG. 7, the description is omitted. Therefore, in FIG. 9, when the method of shifting the phase of the time code sequence so as to match the phase of the video sequence and the time code sequence after the frame rate is changed, the second condition can be satisfied, but the first condition is satisfied. The condition 1 cannot always be satisfied.

  In addition, the conventional imaging apparatus has a problem that the second condition and the third condition cannot be made compatible during frame rate conversion. Hereinafter, description will be made with reference to FIGS. 10 to 11.

  FIG. 10 is an explanatory diagram in the case of performing synchronization by the input time code during the frame rate conversion from the 24p video signal to the 60p video signal. The frame rate conversion means performs frame rate conversion from a 24p video signal to a 60p video signal, and the video sequences are VS24p6 and VS24p8. The time code synchronization process is performed at the point SLV 24p1. Note that the signal delay that occurs during frame rate conversion is not shown.

  The base time code is a time code before synchronization by the input time code, and the time code sequence is TS24pbase1. At this time, the phases of the video sequence and the time code sequence are the same.

  The input time code is a time code input from the outside of the imaging apparatus, and the value of the time code and the time code sequence are arbitrary. In the figure, the time code sequence of the input time code is TS24pin1. The post-synchronization time code is a time code output from the imaging apparatus, and matches the base time code before the time code synchronization process, and becomes TS24 pslave1 after the time code synchronization process and matches the input time code. However, after the time code synchronization process, the phases of the video sequence VS24p8 and the time code sequence TS24pslave1 do not match. As described above, the phase of the time code sequence after the time code synchronization processing matches the phase of the time code sequence of the input time code, but does not match the phase of the video sequence.

  FIG. 11 is an explanatory diagram when synchronization is performed using an input time code having an arbitrary time code sequence during frame rate conversion from a 24p video signal to a 60p video signal. The phase that can be taken as the time code sequence of the input time code with respect to the phase VS 24p7 of the 24p video sequence is the input 24p time code sequence of the input time code (pattern 5) from the input 24p time code sequence TS24pin21 of the input time code (pattern 1). There are 5 types up to TS24pin25. Since the time code sequence after the time code synchronization processing matches the time code sequence of the input time code, the video sequence and the time are processed after the time code synchronization processing, except when the input is performed with the phase of the input time code (pattern 1). The phase of the code sequence cannot be matched. Note that the above-described method of shifting the phase of the time code sequence by correcting the time code cannot be used because it contradicts the concept of synchronizing the time code. Therefore, in FIG. 11, the third condition can be satisfied, but the second condition is not always satisfied.

  In view of the above problems, the present invention provides a configuration capable of satisfying a desired condition related to time code while matching the phases of a video sequence and a time code sequence in an imaging apparatus capable of changing an imaging frame rate. With the goal.

  In order to solve the above-described conventional problems, the imaging apparatus of the present invention can change the imaging frame rate, which is a frame rate for imaging video, and converts the video signal captured at the imaging frame rate into an output frame rate for output. An image pickup means for outputting video sequence information for specifying a start position of a video sequence as a repetition unit when outputting a video signal and converting a frame rate from an imaging frame rate to an output frame rate, and synchronizing with an output video signal Time code generating means for generating the time code information, an operating means for generating a frame rate change command, and time code information and imaging means captured from the time code generating means when notified of the frame rate change by the operating means According to the video sequence information captured from A system control unit that changes the frame rate of the first frame rate as a procedure for changing the imaging frame rate from the first frame rate to the second frame rate. The first video sequence, which is a repetition unit when the frame rate is changed to the second frame rate and the period for imaging at the third frame rate is converted from the first frame rate to the output frame rate. Length of the second video sequence, which is a repetition unit when converting the frame rate from the second frame rate to the output frame rate, and the time code value at the beginning of the first video sequence immediately before the frame rate change. To be determined.

  With this configuration, by selecting an appropriate frame rate and selecting the frame rate change timing, the phase of the video sequence after changing the frame rate and the phase of the time code sequence after changing the frame rate while maintaining the continuity of the time code Can be matched.

  In addition, the imaging apparatus of the present invention can change the imaging frame rate, converts a video signal captured at the imaging frame rate into an output frame rate and outputs it as an output video signal, and specifies the start position of the video sequence. An image pickup means for outputting video sequence information, a time code processing means for outputting a time code input from the outside as an input time code, and a time code processing means for inputting the time code from the outside, A system control unit that changes the frame rate of the imaging unit according to the input time code captured from the time code processing unit and the video sequence information captured from the imaging unit, and the system control unit determines the imaging frame rate, Once from the first frame rate 3 is a repetitive unit for changing to the first imaging frame rate again via the frame rate of 3 and converting the period of imaging at the third frame rate from the first frame rate to the output frame rate. The first video sequence is determined based on the length of the first video sequence and the time code value at the beginning of the first video sequence immediately before the frame rate is changed.

  By selecting an appropriate frame rate and selecting a frame rate change timing with this configuration, the phases of the video sequence and the time code sequence can be made to coincide with each other while synchronizing with the time code inputted externally.

  According to the imaging apparatus of the present invention, when the frame rate of the imaging apparatus is changed in the production process in a digital cinema, the phase of the video sequence and the time code sequence can be matched while maintaining the continuity of the time code. Therefore, even though the operator of the non-linear editor intended to save it as a single file, it was saved as multiple files and the efficiency of the editing process, which is a later process, was reduced, or automatic import was performed. Although it was intended, it is possible to prevent the occurrence of problems such as interruption during the process and the importing operation must be performed again. In addition, when the completed video signal is re-converted to an arbitrary frame rate in addition to the frame rate used at the time of editing, it can be easily converted by using a time code.

  Further, according to the imaging apparatus of the present invention, in the production process in the digital cinema, when the time code is synchronized when shooting with the multi-camera, the phase of the video sequence and the time code sequence is performed even after the time code is synchronized. Therefore, when the completed video signal is re-converted and distributed to an arbitrary frame rate as well as the frame rate used at the time of editing, it can be easily converted by using a time code.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 is a configuration diagram of an imaging apparatus according to Embodiment 1 of the present invention. In FIG. 1, an imaging unit 1 performs imaging at an imaging frame rate corresponding to frame rate change information FRp from the system control unit 2, performs conversion processing to a predetermined frame rate, and outputs the result. Also, the video sequence information FRseq of the frame rate conversion process is output to the system control unit 2. Here, the video sequence information is information for specifying the start position of the video sequence during frame rate conversion. In this embodiment, the read memory number is the video sequence information FRseq. The imaging unit 1 includes a CCD driving unit 5 and a frame rate conversion unit 6. The CCD driving means 5 sets the imaging frame rate according to the frame rate change information FRp from the system control unit 2, and drives the CCD at the imaging frame rate to output a video signal. As an imaging frame rate, for example, an arbitrary value from 1p (having one progressive image per second) to 60p (having 60 progressive images per second) is assumed. The frame rate conversion means 6 receives the video signal output from the CCD drive means 5 as input, performs frame rate conversion processing to an output frame rate using a memory, and outputs it. In this embodiment, the output frame rate is 60p. That is, the frame rate conversion means 6 performs frame rate conversion processing on the video signal imaged at the imaging frame rate, and outputs a 60p video signal as Vout to the outside of the imaging device.

  The time code generation means 3 generates a time code so as to continuously advance every TC frame in synchronization with the output 60p video signal, and outputs this to the system control unit 2 as time code information TCdet. , TCout and output to the outside of the imaging apparatus. The time code used here is a time code conforming to the standard SMPTE12M defined by SMPTE (American Film and Television Engineers Association). It consists of hour, minute, second and frame elements. Since the time code of the 30-frame system is used in this embodiment, the possible values are 00:00:00 00 frames to 23:59:59 seconds 29 frames. Since it has a time code of 30 frames per second, the same time code may be generated for a plurality of continuous videos in a video signal in which the number of videos per second exceeds 30. For example, in the 60p video signal, the same time code is generated every two consecutive video frames. In each figure, only the frame value is shown for convenience.

  The operation unit 4 receives input from the user and outputs the information to the system control unit 2. When the user is instructed to change the frame rate by menu setting or button operation, the operation means 4 outputs frame rate change operation information OP to the system control unit 2. Note that the operation unit 4 may output the frame rate change operation information OP by a trigger such as a button operation in accordance with automatic frame rate change information set in advance by the user.

  When the frame rate change operation information OP is input from the operation unit 4, the system control unit 2 generates an appropriate frame rate change timing and an appropriate frame rate to be changed from the time code information TCdet and the video sequence information FRseq. The frame rate change information FRp is output to the image pickup means 1.

  Next, a method for determining the head of the video sequence of the video signal output from the imaging means 1 based on the video sequence information FRseq will be described. FIG. 12 is an explanatory diagram relating to a method of determining the head of a video sequence when frame rate conversion from a 24p video signal to a 60p video signal is performed with an imaging frame rate of 24p and an output frame rate of 60p. The description of the same parts as those in FIG. 4 is omitted. The imaging unit 1 reads out and outputs a memory number as video sequence information FRseq every 1/60 seconds according to the output frame rate of 60p. The system control unit 2 inputs and stores the video sequence information FRseq every 1/60 seconds. Further, the system control unit 2 has a 24p video sequence number as a counter that updates the value by 1 every 1/60 seconds, and discriminates the head of the video sequence by clearing to 0 at an appropriate timing. In the case of FIG. 12, the timing for clearing the 24p video sequence number to 0 is as follows. That is, when the video sequence information FRseq is the same value three times in succession and is updated to a different value next time, the 24p video sequence number is cleared to 0 if it matches the time code update timing of the time code information TCdet. . In this way, the system control unit 2 can clear the 24p video sequence number from the input video sequence information FRseq and the time code information TCdet, and the video signal when the 24p video sequence number is 0. It can be determined that Vout is the head of the video sequence. For example, in FIG. 12, the video sequence information FRseq becomes the same value three times in succession, and is then updated to a different value at five locations from SEQ24pnum11 to SEQ24pnum15. Of these, the two timings of SEQ24pnum12 and SEQ24pnum14 coincide with the update timing of the time code information TCdet. If the 24p video sequence number is cleared to 0 at these two timings, the video signal is displayed when the 24p video sequence number is 0. It can be determined that Vout is the head of the video sequence. Note that it is not necessary to determine the beginning of the video sequence every time while the frame rate is not changed. Once the determination is made, the current frame rate is 24p, so that the length of the video sequence is 10 video frames. Thus, the 24p video sequence number after 9 may be updated to 0 without making the above determination.

  FIG. 13 is an explanatory diagram relating to a method of determining the head of a video sequence at the time of frame rate conversion from a 20p video signal to a 60p video signal. The description of the same parts as those in FIG. 5 is omitted. Also in this case, as in FIG. 12, the timing for clearing the 20p video sequence number to 0 is as follows. That is, when the video sequence information FRseq has the same value three times in succession and is updated to a different value next time, the 20p video sequence number is cleared to 0 if it matches the time code update timing of the time code information TCdet. I will decide. In this way, when the 20p video sequence number is 0, it can be determined that the video signal Vout is the head of the video sequence. For example, in FIG. 13, the video sequence information FRseq becomes the same value three times in succession and is then updated to a different value at seven points from SEQ20pnum11 to SEQ20pnum17. Of these, the update timing of the time code information TCdet coincides with three locations of SEQ20pnum12, SEQ20pnum14, and SEQ20pnum16. If the 20p video sequence number is cleared to 0 at these three timings, It can be determined that the video signal Vout is the head of the video sequence. Note that it is not necessary to determine the start of the video sequence every time while the frame rate is not changed. Once the determination is made, the current frame rate is 20p, so the length of the video sequence is 6 video frames. Therefore, the 20p video sequence number after 5 may be updated to 0 without making the above determination.

  Next, referring to FIG. 14 and FIG. 15, when the frame rate of the imaging apparatus is changed from 20p to 24p, a specific method for matching the phase of the video sequence and the time code sequence while maintaining the continuity of the time code will be described. Explained.

  FIG. 14 shows that when the time code information TCdet is the time code (pattern 1) in FIG. 9 and the frame rate of the imaging apparatus is changed from 20p to 24p, the video sequence and time are maintained while maintaining the continuity of the time code. It is explanatory drawing of the method of making the phase of a code sequence correspond.

  When the frame rate conversion from 20p to 60p is performed in the imaging unit 1, when the frame rate is changed from 20p to 24p by the frame rate change operation information OP from the operation unit 4, the system control unit 2 Control is performed to change the frame rate from 20p to 30p as a transit frame rate and then to 24p. The transit frame rate may be arbitrary as long as it is other than the frame rate before the change and the frame rate after the change, but 30p is used in the present embodiment.

  The value of the via frame rate may be determined in advance, or control may be performed to automatically select the shortest frame rate value of the video sequence from among the imaging frame rates that can be selected by the imaging apparatus. Alternatively, control may be performed to automatically select a frame rate value that is intermediate between the frame rate before the change and the frame rate after the change. Of course, the user may be able to select by a menu or the like. When the shortest frame rate value of the video sequence is used among the imaging frame rates that can be selected by the imaging apparatus, there is an advantage that the change of the frame rate can be completed in the shortest time. In addition, when a frame rate value that is intermediate between the frame rate before the change and the frame rate after the change is used, it is possible to obtain a smooth video effect as the appearance of the image when the frame rate is changed. There are advantages. Further, in the present embodiment, description is given via one type of frame rate, but a plurality of types of frame rates may be used. In that case, there is an advantage that a smoother video effect can be obtained by changing the transit frame rate stepwise from the frame rate before the change to the frame rate after the change.

  First, the system control unit 2 obtains the number of inserted frames to be inserted between 20p and 24p, that is, a period during which the imaging unit 1 captures an image at a frame rate 30p that is a transit frame rate. In FIG. 14, it is determined that the beginning of the video sequence immediately before the frame rate change in the video sequence after the frame rate conversion from 20p to 60p is the timing VSEQtop20p101 at which the video sequence number is updated to 0. Further, it is detected that the time code information TCdet at this time is a value 0 which is a 20p video sequence start time code TCtop20p101. Video sequence at the time of frame rate conversion from 20p to 60p (hereinafter referred to as a 20p video sequence. The same applies to other frame rates) The length is 3TC frames (6 video frames of a 60p video signal). Therefore, the time code of the next frame after one video sequence of 20p is 0 + 3 = 3. In order to convert this into a 24p video sequence, the remainder obtained by dividing the 24p video sequence length by 5TC frames (10 video frames of a 60p video signal) is 3 MOD 5 = 3. Since it is sufficient that the number of inserted frames to be obtained is added to the head of the 24p video sequence, the number of inserted frames is set to this value from a 24p video sequence length of 5 TC frames (10 video frames of a 60p video signal). Is subtracted to be 5-3 = 2, and the number of inserted frames at the frame rate of 30p is found to be 2TC frames.

Expressing the above in a generalized expression, the number of inserted frames of the video signal of the transit frame rate is (LEENptc− (TCxptc + LENxptc) MOD LEENyptc) MOD LEENypc (Expression 1)
It becomes. Where LENxptc is the sequence length of the frame rate before the change, LENyptc is the sequence length of the frame rate after the change, TCxptc is the frame value of the time code at the beginning of the sequence of the frame rate before the change, and MOD is the remainder of the division Let it be an operator. The unit is a TC frame.

For further generalization, when Equation 1 is converted into an equation for obtaining a video frame,
(LENyp− (TCxp * 2 + LENxp) MOD LENyp) MOD LENyp (Formula 2)
It becomes. Where LENxp is the sequence length of the frame rate before the change, LENyp is the sequence length of the frame rate after the change, TCxp is the frame value of the time code at the beginning of the sequence of the frame rate before the change, and MOD is the remainder of the division Let it be an operator. The unit is a video frame.

  Here, the reason why the time code is doubled is that the TC frame is converted into a video frame. In the case of 60p video, the video frame length is 1/60 seconds, and the TC frame length of the 30-frame system is 1/30 seconds, so TC frame length / video frame length = 60/30 = 2. Multiply.

When the number of inserted frames at the frame rate of 30p in FIG.
(LENyp- (TCxp * 2 + LENxp) MOD LENyp) MOD LENyp
= (LEN24p- (TC20p * 2 + LEN20p) MOD LEN24p) MOD LEN24p
= (10- (0 * 2 + 6) MOD 10) MOD 10
= 4
It becomes. The unit is a 60p video frame.

  Next, the system control unit 2 outputs frame rate change information FRp to the imaging unit 1 so that the frame rate becomes 30p from the timing FRP20p30p101 after the 20p video sequence VS20p101 ends. This timing can be obtained by referring to the video sequence number. In the present embodiment, the timing FR30p101 is the timing one frame before 60p before the actual change of the frame rate, that is, the timing FR30p101 at which the video sequence number of 20p is updated to 5. The imaging unit 1 changes the frame rate from the timing of the next frame to which the frame rate change information FRp is input.

  Next, from the timing FRP30p24p101 after the passage of the number of inserted frames at the frame rate of 30p, the system control unit 2 sets the frame to the imaging unit 1 so that the frame rate specified by the frame rate change operation information OP from the operation unit 4 The rate change information FRp is output. In this case, since the obtained frame count is 4 frames in a 60p video frame, the timing is FR24p101, which is 4 frames after the timing FR30p101 instructed to be 30p.

  By performing the above control, it is possible to match the phase of the 24p video sequence VS24p101 after the frame rate change with the phase of the 24p time code sequence TS24p101 after the frame rate change while maintaining the continuity of the time code.

FIG. 15 shows a case where the time code information TCdet is the time code (pattern 3) in FIG. 9 and the video sequence is maintained while maintaining the continuity of the time code when the frame rate of the imaging apparatus is changed from 20p to 24p. It is explanatory drawing of the method of making the phase of a time code sequence correspond. Similarly to the case of FIG. 14, when the number of inserted frames at a frame rate of 30p is obtained using Equation 2,
(LENyp- (TCxp * 2 + LENxp) MOD LENyp) MOD LENyp
= (LEN24p- (TC20p * 2 + LEN20p) MOD LEN24p) MOD LEN24p
= (10- (2 * 2 + 6) MOD 10) MOD 10
= 0
It becomes. The unit is a 60p video frame. Since the number of inserted frames at the frame rate of 30p is 0 video frame, it can be seen that it is not necessary to insert a frame at the frame rate of 30p.

  Next, the system control unit 2 sets the frame rate to the imaging unit 1 so that the frame rate is instructed by the frame rate change operation information OP from the operation unit 4 from the timing FRP20p24p103 after the 20p video sequence VS20p103 ends. The change information FRp is output. This timing can be obtained by referring to the video sequence number, and in the present embodiment, the timing FR24p103 in which the video sequence number of 20p is updated to the value 5 is used.

  By performing the above control, the phase of the 24p video sequence VS24p103 after changing the frame rate and the phase of the 24p time code sequence TS24p103 after changing the frame rate can be matched while maintaining the continuity of the time code.

In the description of FIG. 15, the description was made without inserting the frame rate 30p, but the video sequence length of the frame rate 24p, that is, 10 video frames may be inserted. In that case, it is derived by the following equation.
(LENyp- (TCxp * 2 + LENxp) MOD LENyp) (Formula 3)
= (10- (2 * 2 + 6) MOD 10)
= 10
The unit is a 60p video frame.

  The same applies when the time code information TCdet is the time code (pattern 2) or (pattern 4) or (pattern 5) in FIG.

  As described above, according to the present invention, even when the frame rate of the imaging device is changed from 20p to 24p, the phase of the video sequence and the phase of the time code sequence can be matched while maintaining the continuity of the time code. I can do it. As a result, the captured video can be taken into the nonlinear editor system and easily edited.

In this embodiment, the 60p video signal is used as the output frame rate, but other frame rates may be used. Further, a progressive video signal may be used, or an interlace video signal may be used. For example, when a 60i video signal is used, since the 60i video signal constitutes one video frame by two video fields, the lengths of the video frame and the TC frame are the same. Therefore, (LENyp− (TCxp + LENxp) MOD LENyp) MOD LENyp
Is the number of video frames to be inserted and is the number of TC frames.

(Embodiment 2)
FIG. 2 is a configuration diagram of the imaging apparatus according to Embodiment 2 of the present invention. Only the parts different from FIG. 1 will be described. The time code processing unit 23 detects the time code TCin2 input from the outside of the imaging apparatus and outputs it as input time code information TCdet2. Also, TCint2 is output as time code information before time code synchronization processing. In addition, time code synchronization processing is performed in accordance with the time code synchronization instruction TCslave2 from the system control unit 22, and output to the outside of the imaging apparatus as TCout2. The system control unit 22 generates an appropriate timing for changing the frame rate and an appropriate frame rate to be changed from the input time code information TCdet2 and the video sequence information FRseq2, and sets it as the frame rate change information FRp2. And a time code synchronization instruction TCslave2 is output to the time code processing means 23. In this embodiment, since the frame rate is not changed by a user operation, the operation means is omitted.

  Next, a method for matching the phase of the video sequence and the time code sequence while synchronizing with the time code input externally will be specifically described with reference to FIG.

  FIG. 16 shows that during the frame rate conversion from 24p to 60p in the imaging device, the time code input from the outside of the imaging device becomes valid at the timing when the base time code is 5, and the input time code information TCdet2 is the time code (FIG. 11). It is explanatory drawing of the method to match | combine the phase of a video sequence and a time code sequence, synchronizing with the time code input externally when it is pattern 2). Note that a time code generated internally before synchronizing with an externally input time code is called a base time code.

  When the time rate input TCin2 from the outside of the imaging apparatus becomes valid when the frame rate conversion from 24p to 60p is performed in the imaging unit 21, the system control unit 22 changes the frame rate from the current 24p to the transit frame. Control is performed to once change the rate to 30p and then to 24p again. The transit frame rate may be arbitrary as long as it is other than the current frame rate, but 30p is used in the description of FIG.

  First, the system control unit 22 obtains the number of inserted frames to be inserted during a period during which the imaging unit 21 performs imaging at a frame rate 30p that is a transit frame rate, that is, 24p. In FIG. 16, it is determined that the beginning of the video sequence immediately before the frame rate change in the video sequence after the frame rate conversion from 24p to 60p is the timing VSEQtop24p201 at which the video sequence number is updated to 0. The method for calculating the video sequence number is the same as in the first embodiment. Also, it is detected that the input time code information TCdet2 at this time is a value 1 which is the 24p video sequence start time code TCtop24p201. Since the length of the 24p video sequence is 5TC frames (10 video frames of the 60p video signal), the input time code of the next frame after the completion of one video sequence of 24p is 1 + 5 = 6. In order to convert this into a 24p video sequence, the remainder obtained by dividing the 24p video sequence length by 5TC frames is 6 MOD 5 = 1. Since it is sufficient that the number of inserted frames to be obtained is added to the head of the 24p video sequence, the number of inserted frames is 5-1 = 4 by subtracting this value from the 5TC frame of the 24p video sequence length. Thus, the number of inserted frames at a frame rate of 30p is determined to be 4TC frames.

The above can be obtained by using the same frame rate before and after the change in Equation 1 used in the first embodiment. In other words, the number of inserted frames of the video signal of the via frame rate is
(LEENptc- (TCxptc + LENxptc) MOD LENyptc) MOD LENyptc
= (LEN24ptc- (TC24ptc + LEN24ptc) MOD LEN24ptc) MOD LEN24ptc
= (5- (1 + 5) MOD 5) MOD 5
= 4
It becomes. The unit is a TC frame.

Similarly, it can be obtained using Equation 2. In other words, the number of inserted frames of the video signal of the via frame rate is
(LENyp- (TCxp * 2 + LENxp) MOD LENyp) MOD LENyp
= (LEN24p- (TC24p * 2 + LEN24p) MOD LEN24p) MOD LEN24p
= (10- (1 * 2 + 10) MOD 10) MOD 10
= 8
It becomes. The unit is a 60p video frame.

  Next, the system control unit 22 outputs the frame rate change information FRp2 to the imaging means 21 so that the frame rate becomes 30p from the timing FRP24p30p201 after the 24p video sequence VS24p201 ends. This timing can be obtained by referring to the video sequence number. In the present embodiment, the timing FR30p201 is the timing one frame before 60p before the actual change of the frame rate, that is, the timing FR30p201 at which the video sequence number of 24p is updated to 9.

  Next, the system control unit 22 outputs the frame rate change information FRp2 to the imaging means 21 so as to return to the frame rate before the change from the timing FRP 30p24p201 after the number of inserted frames at the frame rate 30p has elapsed. In this case, since the number of frames obtained is 8 frames in a 60p video frame, the timing FR24p201 is 8 video frames after the timing FR30p201 instructed to be 30p.

  Further, the system control unit 22 outputs a time code synchronization instruction TCslave2 to the time code processing unit 23 so that the time code synchronization process is performed at the timing FRP24p30p201 or FRP30p24p201. The timing is one frame before the frame on which the synchronization processing is actually performed, and is FR30p201 or FR24p201, similarly to the frame rate change timing. When 30p is selected as the transit frame rate, the video code sequence of the video signal output from the imaging apparatus and the time code sequence of the time code output from the imaging apparatus are the same regardless of the timing code synchronization process. The phases match.

  By performing the above control, it is possible to match the phases of the video sequence and the time code sequence while synchronizing with the time code input from the outside.

  The same applies when the input time code information TCdet2 is the time code (pattern 1) or (pattern 3) or (pattern 4) or (pattern 5) in FIG. If the input time code information TCdet2 is the time code (pattern 1) in FIG. 11, the number of frames inserted at the frame rate 30p is 0, but in this case, no frame at the frame rate 30p is inserted, It may be synchronized with an externally input time code at the beginning timing of the video sequence after rate conversion, or the length of a video sequence with a frame rate of 24p, that is, 10 video frames may be inserted.

  Next, with reference to FIG. 17, a specific method for matching the phases of the video sequence and the time code sequence while synchronizing with the externally input time code in the case where the externally input time code is shifted in the field will be described. Explained.

  In the progressive video signal, field information handled by the interlaced video signal is not defined, and therefore the input time code may be shifted by one field from the phase of the time code generated by the imaging apparatus.

  FIG. 17 shows the time code input from the outside when the time code input from the outside of the image pickup apparatus becomes valid during the frame rate conversion from 24p to 60p in the image pickup apparatus and the input time code information TCdet2 is shifted in the field. It is explanatory drawing of the method of making the phase of a video sequence and a time code sequence correspond, synchronizing.

  When the time rate input TCin2 from the outside of the imaging apparatus becomes valid when the frame rate conversion from 24p to 60p is performed in the imaging unit 21, the system control unit 22 changes the frame rate from the current 24p to the transit frame. Control is performed to change the rate once to 60p and then to 24p again. The transit frame rate may be arbitrary as long as the length of the video sequence is an odd number, but 60p is used in the description of FIG.

  First, the system control unit 22 obtains the number of inserted frames with a frame rate of 60p, which is a transit frame rate. In FIG. 17, it is determined that the video sequence head after the frame rate conversion from 24p to 60p is the timing VSEQtop24p202 at which the video sequence number is updated to 0. Further, it is detected that the input time code information TCdet2 at this time is the 24p video sequence head time code TCtop24p202. At this time, it is also detected at the same time that the update timing is shifted from the base time code which is the time code before the time code synchronization processing. This can be detected by comparing the update timing of the input time code information TCdet2 and the time code information TCint2 before the time code synchronization process every 1/60 seconds. In the case of FIG. 17, when VSEQtop24p202 is recognized, since the time of 1/60 seconds has elapsed since the input time code information TCdet2 is updated to the value 4, the 24p video sequence head time code TCtop24p202 is set to 0.5 It is recognized that the value is 4.5. Note that the transit frame rate may be determined after detecting whether or not there is a field shift in the input time code. For example, when the input time code is not shifted in the field, the transit frame rate may be set to 30p, and when the input time code is shifted in the field, it may be set to 60p.

  Since the length of the 24p video sequence is 5TC frames (10 video frames of the 60p video signal), the input time code of the next frame after the completion of one video sequence of 24p is 4.5 + 5 = 9.5. In order to convert this into a 24p video sequence, the remainder obtained by dividing the 24p video sequence length by 5TC frames is 9.5 MOD 5 = 4.5. Since it is only necessary to add the number of insertion frames to be obtained to the beginning of the 24p video sequence, the number of insertion frames is 5 to 4.5 by subtracting this value from the 5TC frame of the 24p video sequence length. = 0.5, and the number of inserted frames at a frame rate of 60p is found to be 0.5TC frames.

The above can be obtained by using the same frame rate before and after the change in Equation 1 used in the first embodiment. In other words, the number of inserted frames of the video signal of the via frame rate is
(LEENptc- (TCxptc + LENxptc) MOD LENyptc) MOD LENyptc
= (LEN24ptc- (TC24ptc + LEN24ptc) MOD LEN24ptc) MOD LEN24ptc
= (5- (4.5 + 5) MOD 5) MOD 5
= 0.5
It becomes. The unit is a TC frame.

Similarly, it can be obtained using Equation 2. In other words, the number of inserted frames of the video signal of the via frame rate is
(LENyp- (TCxp * 2 + LENxp) MOD LENyp) MOD LENyp
= (LEN24p- (TC24p * 2 + LEN24p) MOD LEN24p) MOD LEN24p
= (10- (4.5 * 2 + 10) MOD 10) MOD 10
= 1
It becomes. The unit is a 60p video frame.

  Next, the system control unit 22 outputs the frame rate change information FRp2 to the imaging means 21 so that the frame rate becomes 60p from the timing FRP24p60p202 after the 24p video sequence VS24p202 ends. This timing can be obtained by referring to the video sequence number. In the present embodiment, the timing FR60p202 is the timing one frame before 60p before the actual frame rate change timing, that is, the timing FR24p when the video sequence number of 24p is updated to the value 9.

  Next, the system control unit 22 outputs the frame rate change information FRp2 to the imaging means 21 so as to return to the frame rate before the change from the timing FRP 60p24p202 after the insertion of the number of inserted frames at the frame rate 60p. In this case, since the number of frames obtained is one frame of 60p video frames, the timing FR24p202 is one frame after the timing FR60p202 instructed to be 60p.

  Further, the system control unit 22 outputs a time code synchronization instruction TCslave2 to the time code processing unit 23 so that the time code synchronization process is performed at the timing FRP60p24p202. The timing is FR24p202.

  By performing the above control, it is possible to match the phases of the video sequence and the time code sequence while synchronizing with the time code input from the outside.

  The image pickup apparatus according to the present invention can match the phase of the video sequence and the time code sequence while maintaining the continuity of the time code even when the frame rate of the image pickup apparatus is changed. Since the phase of the video sequence and the time code sequence can be matched while synchronizing with the code, it is useful as an imaging device or the like used in the digital cinema production field that produces video equivalent to a film cinema system.

1 is a configuration diagram of an imaging device according to Embodiment 1 of the present invention. Configuration diagram of imaging apparatus according to Embodiment 2 of the present invention Configuration diagram of an imaging device used in conventional digital cinema production The figure which showed the frame rate conversion method from a 24p video signal to a 60p video signal The figure which showed the frame rate conversion method from a 20p video signal to a 60p video signal Explanatory drawing when the converted 60p video signal is converted back to a 24p video signal Explanatory drawing when changing the frame rate from 20p to 24p during frame rate conversion from 20p video signal to 60p video signal When the frame rate is changed from 20p to 24p during the frame rate conversion from the 20p video signal to the 60p video signal, the time code sequence is set so that the phase of the video sequence matches the time code sequence after the frame rate change. Illustration of how to shift the phase Explanatory diagram when changing the frame rate from 20p to 24p when the phase of the video sequence before the frame rate change and the phase of the time code sequence are arbitrary during the frame rate conversion from the 20p video signal to the 60p video signal Explanatory diagram in the case of synchronization by input time code during frame rate conversion from 24p video signal to 60p video signal Explanatory diagram when synchronization is performed with an input time code having an arbitrary time code sequence during frame rate conversion from a 24p video signal to a 60p video signal Explanatory drawing about the method of discriminating the head of a video sequence at the time of frame rate conversion from 24p video signal to 60p video signal Explanatory drawing about the method of discriminating the head of a video sequence when converting a frame rate from a 20p video signal to a 60p video signal When the time code information TCdet is the time code (pattern 1) in FIG. 9 and the frame rate of the imaging device is changed from 20p to 24p, the phase of the video sequence and the time code sequence is maintained while maintaining the continuity of the time code. Illustration of how to match When the time code information TCdet is the time code (pattern 3) in FIG. 9 and the frame rate of the imaging apparatus is changed from 20p to 24p, the video sequence and the time code sequence are maintained while maintaining the continuity of the time code. Explanatory diagram of how to match phases When the time code input from the outside of the imaging apparatus becomes valid during the frame rate conversion from 24p to 60p, and the input time code information TCdet2 is the time code (pattern 2) in FIG. 11, it is synchronized with the time code input externally. While explaining the method of matching the phase of the video sequence and the time code sequence When the time code input from the outside of the imaging apparatus becomes valid during the frame rate conversion from 24p to 60p, and the input time code information TCdet2 is out of the field, the video sequence and the time sequence are synchronized with the externally input time code. Explanatory diagram of how to match the phase of the time code sequence

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Imaging means 2 System control part 3 Time code production | generation means 4 Operation means 5 CCD drive means 6 Frame rate conversion means 21 Imaging means 22 System control part 23 Time code processing means 25 CCD drive means 26 Frame rate conversion means 31 Imaging means 32 System Control unit 34 Operating means 35 CCD drive means 36 Frame rate conversion means

Claims (6)

An imaging frame rate, which is a frame rate for imaging video, can be changed, and a video signal captured at the imaging frame rate is converted into an output frame rate and output as an output video signal, and from the imaging frame rate to the output frame Imaging means for outputting video sequence information for specifying a start position of a video sequence that is a repetition unit when converting a frame rate to a rate;
Time code generating means for generating time code information synchronized with the output video signal;
Operation means for generating a frame rate change command;
A system control unit that changes the frame rate of the imaging unit according to the time code information captured from the time code generation unit and the video sequence information captured from the imaging unit when a frame rate change is notified by the operation unit; With
The system control unit, as a procedure for changing the imaging frame rate from the first frame rate to the second frame rate, temporarily changes the second frame rate from the first frame rate via the third frame rate. The length of the first video sequence, which is a repetition unit when the frame rate is changed from the first frame rate to the output frame rate, and the period of imaging at the third frame rate is changed to the frame rate, 2 based on the length of the second video sequence, which is a repetition unit when converting the frame rate from the frame rate of 2 to the output frame rate, and the value of the time code at the beginning of the first video sequence immediately before the frame rate change. Configured as
Imaging device. The system control unit selects the third frame rate so that the length of the third video sequence, which is a repetition unit when converting the frame rate from the third frame rate to the output frame rate, is the shortest. Configured as
The imaging device according to claim 1. The system control unit is configured to select a frame rate value that is intermediate between the first frame rate and the second frame rate as the third frame rate.
The imaging device according to claim 1. The system control unit gradually selects a plurality of frame rate values that are intermediate between the first frame rate and the second frame rate as the third frame rate, and gradually changes the frame rate. Configured as
The imaging device according to claim 1. An imaging frame rate, which is a frame rate for imaging video, can be changed, and a video signal captured at the imaging frame rate is converted into an output frame rate and output as an output video signal, and from the imaging frame rate to the output frame Imaging means for outputting video sequence information for specifying a start position of a video sequence that is a repetition unit when converting a frame rate to a rate;
A time code processing means for outputting an externally input time code as an input time code;
When the time code processing unit receives an external time code and starts outputting the input time code, the input time code fetched from the time code processing unit and the video sequence information fetched from the imaging unit are used. A system control unit for changing the frame rate of the imaging means,
The system control unit changes the imaging frame rate from the first frame rate to the first imaging frame rate once again via the third frame rate, and performs imaging at the third frame rate. The length of the first video sequence, which is a repetition unit when converting the frame rate from the first frame rate to the output frame rate, and the value of the time code at the beginning of the first video sequence immediately before the frame rate change Configured to make decisions based on
Imaging device. The system control unit selects the third frame rate so that the length of the third video sequence, which is a repetition unit when converting the frame rate from the third frame rate to the output frame rate, is the shortest. Configured
The imaging device according to claim 5.

Images