JP3890872B2 - Information editing device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an information editing apparatus for recording digital data on a magnetic tape and reproducing it from the magnetic tape, and more particularly to recording and editing of a digitized video signal or audio signal.
[0002]
[Prior art]
In a digital video tape recorder for broadcasting stations (hereinafter referred to as a broadcasting D-VTR), for example, an already recorded audio signal and another audio signal are used by using a magnetic tape on which a video signal and an audio signal are recorded. Some of them have a pre-read editing function that mixes them and records them again at the original location, or records the sound later while watching the reproduced video.
[0003]
Hereinafter, a conventional broadcast D-VTR having such an editing function will be described with reference to the drawings. FIG. 10 is a schematic view showing a head arrangement on a rotating cylinder of a conventional broadcasting D-VTR. FIG. 10 is a view of the rotary cylinder 1 as seen from above. In FIG. 10, the rotating cylinder 1 rotates counterclockwise. The rotary cylinder 1 is mounted with recording heads 3 and 4 and heads 5 and 6 for preceding reproduction or simultaneous reproduction mounted on electromechanical conversion elements 7 and 8. In addition, the magnetic tape 2 runs on the rotating cylinder 1 while being obliquely wound over a section of a half circumference (180 degrees).
[0004]
FIG. 11 is a diagram showing the positional relationship between the recording track pattern on the magnetic tape 2 and the head. In FIG. 11, a video signal and an audio signal are already recorded on the magnetic tape 2, and tracks 9a to 9i and the like are formed obliquely. Here, the magnetic tape 2 is always reproduced at a constant speed from right to left as viewed in the drawing. Therefore, signals are recorded in the order of 9a, 9b, 9c,. In the case of performing the preceding reproduction, the electromechanical conversion element 7 is driven to the preceding reproduction position, and the preceding reproduction head 5 precedes the recording head 3 by 4 tracks (a signal earlier in time was recorded). ) Play the track. That is, when the recording head 3 is on the track 9b, the preceding reproducing head 5 is on the track 9f preceding by four tracks. Although not shown, similarly, when the recording head 4 is positioned on the tape, the electro-mechanical conversion element 8 is driven to the preceding reproduction position, and the preceding reproduction head 6 is a track preceding the recording head 4 by 4 tracks. Play.
[0005]
Next, the configuration of this conventional broadcasting D-VTR and the operation in the case where a previously recorded audio signal and another audio signal are mixed and recorded in the original location will be described. FIG. 12 shows a configuration for editing an audio signal already recorded by a conventional broadcasting D-VTR. In FIG. 12, the electromechanical conversion elements 7 to 8 drive the preceding reproducing heads 5 to 6 mounted by the element driving circuit 14 to a position 4 tracks ahead of the recording heads 3 to 4, and the magnetic tape 2 is driven. Driven by a tape drive circuit 15 and a capstan motor 17. The signal reproduced by the preceding reproducing heads 5 to 6 is supplied to the reproducing processing circuit 13 through the head switch 12. The head switch 12 is controlled by a control signal (not shown) synchronized with the rotation of the rotary cylinder 1, and selects the preceding reproducing head located on the magnetic tape. The reproduction processing circuit 13 performs demodulation, error correction processing and deshuffling processing on the reproduction signal 22 selected by the head switch 12, and outputs a signal 18 which has been restored to the original digitized video signal and audio signal form. .
[0006]
The signal 18 is input to the mixing circuit 16. Further, another audio signal 19 to be mixed with the recorded audio signal is also input to the mixing circuit 16. In the mixing circuit 16, the reproduced audio signal and the audio signal 19 are mixed to obtain a new audio signal, and the signal 20 is output as a new digital recording signal that is combined with the reproduced video signal.
[0007]
The signal 20 obtained in this way is input to the recording processing circuit 11. The recording processing circuit 11 performs shuffling processing, error correction coding, modulation, etc. on the signal 20 and outputs a signal 21. The signal 21 is supplied to the recording heads 3 to 4 through the head switch 10 and is overwritten and recorded on all or a part of the tracks on the magnetic tape. The head switch 10 is controlled by a control signal (not shown) synchronized with the rotation of the rotary cylinder 1, and selects a recording head located on the tape.
[0008]
FIG. 13 is a time chart showing a temporal relationship between the signal 22 and the signal 21. FIG. 13 (a) shows a signal 22, and G, H, I, etc. are signals reproduced from the tracks 7g, 7h, 7i in FIG. 13, respectively. Here, the signal 22 is delayed by the time required for the magnetic tape 2 to travel about 4 tracks due to the processing time required for the process from the reproduction processing circuit 13, the mixing circuit 16, and the recording processing circuit 11 until reaching the signal 21. The For example, the G portion of the signal 22 reproduced from the track 7g by the preceding reproducing head 5 is mixed with the audio signal 19 in the mixing circuit 16 via the reproduction processing circuit 13, and further to G1 of the signal 21 via the recording processing circuit 11. Become. The state of the signal 21 at this time is shown in FIG. Thus, the signal 21 is delayed by about 4 tracks with respect to the signal 22.
[0009]
Here, as described above, the preceding reproducing heads 5 and 6 are configured to reproduce the track that precedes the recording heads 3 and 4 by 4 tracks respectively (the previous signal is recorded in time). It is. As a result, when G1 of the signal 21 is supplied to the recording head, the recording head is positioned on the track 7g where the G of the original signal 22 was recorded and can be recorded at the original position on the magnetic tape. .
[0010]
As described above, in the conventional broadcast D-VTR, it takes from reproduction to recording by driving the electro-mechanical conversion element to the preceding reproduction position so as to reproduce the track temporally preceding the recording head. An editing function is realized that absorbs the delay time, mixes an already recorded audio signal and another audio signal, and records the mixed signal again at the original location.
[0011]
[Problems to be solved by the invention]
As described above, in a conventional broadcasting D-VTR, an electro-mechanical conversion element is used in order to realize an editing function of mixing an audio signal that has already been recorded with another audio signal and recording it again at the original location. It is necessary to provide a mechanism for moving the head to the preceding position or to provide a preceding reproducing head. However, when the rotating cylinder is reduced in size in order to reduce the size and weight of the device, there is a problem that it is difficult to mount an electromechanical conversion element or to provide a dedicated leading head. In addition, when the time required for processing the reproduced data and recording it again is large, it is necessary to make the track reproduced by the preceding reproducing head significantly ahead of the recording head. There is also a problem that it may not be possible to provide the preceding reproducing head mechanically.
[0012]
Accordingly, an object of the present invention is to edit an information recorded with a pre-read editing function such as processing an already recorded signal and recording it again in the original place without recording a preceding reproducing head or recording audio in accordance with the video. Is to provide a device.
[0013]
[Means for Solving the Problems]
The information editing apparatus of the present invention, after reproducing the reproduction data from the magnetic tape at high speed, rewinds the magnetic tape only in the reproduced section and records a predetermined amount of edit data at the reproduced section at high speed, and is not recorded at high speed in the reproduced section. The section has a configuration in which the process of idling the magnetic tape is sequentially repeated.
[0014]
With the above-described configuration, the present invention provides information having a pre-read editing function in which an already recorded signal is processed and recorded again in the original place or audio is recorded in accordance with the video without providing a preceding playback head. An editing device can be provided.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
According to a first aspect of the present invention, there is provided a tape driving means for driving a magnetic tape and reproduction data from the magnetic tape driven by the magnetic tape driving means. Than normal playback high speed At a second transfer rate Reproduction means for reproduction, second memory for writing and reproducing the reproduction data reproduced by the reproduction means, and editing such as mixing other signals with the data read from the second memory The first memory continuously writing and reading the edit data obtained by applying the data, and the amount of data remaining in the first memory to the magnetic tape driven by the magnetic tape driving means is less than a predetermined amount Until Than normal recording high speed At the first transfer rate Recording means for recording; The tape driving means, the reproducing means, the second memory, the first memory, and the recording Control means for controlling the operation of the means, the control means until the write amount of the reproduction data in the second memory reaches a predetermined amount Of the magnetic tape at a second transfer rate. After playing, rewind the magnetic tape to the desired position, The magnetic tape is transferred to the magnetic tape at the first transfer rate until the amount of data remaining in the first memory becomes a predetermined amount or less. After recording, Continue in front Reprint Life ended position Until said magnetic tape The sky Run, Further, the second transfer rate Regeneration After The rewind, the At the first transfer rate Record, before Sky The information editing apparatus is characterized in that all or a part of each means is controlled so as to sequentially repeat the running. With this configuration, the information editing apparatus of the present invention can perform recording without providing a preceding reproducing head. It is possible to realize a pre-read editing function such as processing the recorded signal and recording it again in the original place, or recording audio in accordance with the video.
[0016]
According to a second aspect of the present invention, there is provided the information editing apparatus according to the first aspect, wherein the storage data amount of the second memory is larger than the storage data amount of the first memory. Thus, the information editing apparatus of the present invention has a high-speed playback data amount that is larger than the high-speed recording data amount, thereby always acquiring playback data for after-roll after the editing OUT, so that high-speed playback after high-speed recording. Therefore, it is not necessary to acquire after-roll data, and the processing can be simplified.
[0017]
According to a third aspect of the present invention, in the first aspect, the read speed of the first memory is set to N1 (N1> 1) double speed during normal recording, and the write speed of the second memory is set to N2 (N2 during normal playback). > 1) A magnetic recording apparatus characterized in that 1 / N1 + 1 / N2 <1 when double speed is achieved. With this configuration, the information editing apparatus of the present invention can continue pre-read editing work continuously. It becomes possible.
[0018]
According to a fourth aspect of the present invention, in the first aspect, the first memory and the second memory comprise a single storage device for writing and reading edited data and for writing and reading reproduced data. With this configuration, the information editing apparatus of the present invention can share the memories of the first memory and the second memory.
[0019]
(Embodiment 1)
Embodiments of the present invention will be described below with reference to the drawings. This embodiment has a function of mixing a signal already recorded on the magnetic tape with another signal and recording it again in the original place, as in the conventional example, and a pre-read editing function without providing a preceding reproducing head. A broadcasting digital VTR that realizes the above will be described.
[0020]
FIG. 1 is a block diagram showing a configuration of an information editing apparatus for editing an audio signal already recorded by the broadcasting D-VTR of the present embodiment. In FIG. 1, the same numbers are assigned to blocks and signals having the same functions as in the prior art.
[0021]
In FIG. 1, 2 is a magnetic tape, 3 and 4 are recording heads for recording signals on the magnetic tape 2 at a second data rate, and 5 and 6 are data recorded on the magnetic tape 2 at a second data rate. The reproducing heads 10 and 12 to be reproduced are controlled by a control signal (not shown) synchronized with the rotation of the rotating cylinder, and one of the recording heads 3 and 4 and the reproducing heads 5 and 6 that are in contact with the magnetic tape 2 is connected. A head switch 11 to be selected performs a shuffling process, error correction coding, modulation, etc. on the input data signal 109, and outputs an output data signal 21 to the head switch 10 at a second data rate. A reproduction processing circuit 15 that performs demodulation, error correction, and deshuffling processing on the input signal 22 and outputs it as a data signal 108. A tape drive circuit that moves, 16 is a mixing circuit that mixes the input reproduction signal 18 and signal 110 and outputs it as a recording signal 20, 17 is a capstan motor that drives the magnetic tape 2, and 100 is output from the mixing circuit 16. Recording signal 20 is continuously stored at the first data rate, and the stored data is intermittently read out at a second data rate that is faster than the first data rate in the recording order, and recorded as data signal 109. A recording memory 101, which is a first memory to be output to the circuit 11, stores data 108 intermittently reproduced by the reproduction processing circuit 13 sequentially at a second data rate, and also stores the first data in the stored order. A reproduction memory, which is a second memory that continuously reads out at a rate and outputs the reproduction signal 18 to the mixing circuit 16; 102, a recording memory 100; Based on the residual data amount in the raw memory 101 and the data signal 108 output from the reproduction processing circuit 13, the operations of the recording memory 100, the reproduction memory 101 and the recording processing circuit 11, the reproduction processing circuit 13, and the tape drive circuit 15 are performed. It is the control circuit which controls.
[0022]
Here, the recording processing circuit 11, the head switch 10, and the heads 3 and 4 constitute recording means for intermittently recording the data read from the recording memory 100, which is the first memory, on the magnetic tape 2. The reproduction processing circuit 13, the head switch 12, and the heads 5 and 6 constitute reproduction means for intermittently reproducing data from the magnetic tape 2 at the second data rate.
[0023]
FIG. 2 is a head layout diagram on the rotary cylinder, and FIG. 3 is a diagram showing the positional relationship between the recording track pattern on the magnetic tape 2 and the head. In FIG. 2, the rotating cylinder 1 rotates counterclockwise. The rotary cylinder 1 is equipped with recording heads 3 and 4 and reproducing heads 5 and 6. The rotating cylinder 1 travels with the magnetic tape 2 being wound obliquely over a section of approximately half a circle (180 degrees). Video signals and audio signals are already recorded on the magnetic tape 2, and tracks 9a, 9b, 9c and the like are formed obliquely as shown in FIG. Here, the magnetic tape 2 is always reproduced at a constant speed from right to left as viewed in the drawing. Therefore, signals are recorded in the order of 9a, 9b, 9c,. The reproducing head 5 reproduces the position delayed by the head allocation angle with respect to the recording head 3 (the signal after the time is recorded). That is, when the recording head 3 is on the track 9a, the reproducing head 5 is on the track 9a delayed by the head allocation angle. Although not shown, similarly, when the recording head 4 is positioned on the tape, the reproducing head 6 reproduces the position delayed with respect to the recording head 4 by the allocation angle. In this embodiment, the recording heads 3 and 4 and the reproducing heads 5 and 6 are arranged at mutually symmetrical positions of the rotary cylinder 1, and these are alternately switched by the head switches 10 and 12.
[0024]
The operation of the information editing apparatus according to this embodiment will be described below.
[0025]
First, the recording operation will be described. A signal 20 that is a digitized video and audio signal is recorded in the recording memory 100 at a first data rate (for example, 15 Mbps) and stored at a second data rate (for example, 60 Mbps) higher than the first data rate. Are read out intermittently in this order and output as a signal 109. Similarly to the conventional example, the signal 109 is subjected to shuffling processing, error correction coding, modulation, and the like in the recording processing circuit 11 and is output as the signal 21. The signal 21 is intermittently recorded on the magnetic tape through the head switch 10 at the data rate of 60 Mbps by the recording heads 3 to 4. That is, the signal 20 which is a continuous signal of 15 Mbps is converted into a signal 21 having a data rate of 60 Mbps which is four times (N1 = 4> 1) higher than 15 Mbps via the recording memory 100 and intermittently applied to the magnetic tape 2. Record.
[0026]
Next, the reproduction operation will be described. During reproduction, data is reproduced intermittently from the magnetic tape 2 by the reproduction heads 5 to 6 at a data rate of 60 Mbps, and an intermittent signal 22 is obtained via the head switch 12. The signal 22 is demodulated, error-corrected and deshuffled by the reproduction processing circuit 13 in the same manner as in the conventional example, sequentially stored in the reproduction memory 101 at a data rate of 60 Mbps, and continuously at a data rate of 15 Mbps in the stored order. Read signal 18 to obtain signal 18. That is, the signal 18 is intermittently reproduced from the magnetic tape at a data rate of 60 Mbps which is four times higher than 15 Mbps (N2 = 4> 1), and a signal 18 which is a continuous signal of 15 Mbps is obtained via the reproduction memory 101. Since N1 = N2 = 4, 1 / N1 + 1 / N2 = 1/2 <1.
[0027]
By the way, when the signal already recorded on the magnetic tape and another signal are mixed and recorded again at the original location, the above intermittent recording operation and intermittent reproduction operation are alternately repeated, The magnetic tape is run at high speed between the recording operation and the reproducing operation. At this time, the control circuit 102 controls the operation of each unit. That is, the recording memory 100 and the recording processing circuit 11 perform an intermittent reading operation and an intermittent recording processing operation, respectively, according to the control signals 103 and 104 from the control circuit 102. Further, the reproduction processing circuit 13 and the reproduction memory 101 perform an intermittent demodulation operation and an intermittent writing operation, respectively, according to control signals 105 and 106 from the control circuit 102. Further, the tape drive circuit 15 that controls the running of the magnetic tape 2 is controlled by a control signal 107 from the control circuit 102. The control circuit 102 receives the signal 108 reproduced from the magnetic tape 2 and the control lines from the reproduction memory 101 and the recording memory 100, thereby grasping the tape running position and the remaining amount of each memory. And reflected in each control signal.
[0028]
Hereinafter, a more specific operation of each block under the control of the control circuit 102 will be described with reference to FIGS. FIG. 4 is a diagram showing a recording state on the magnetic tape 2. In FIG. 4, reference numerals 110 to 116 are data blocks in which 2000 tracks formed on the magnetic tape 2 are grouped, and each of the blocks A, B, B, C, D, E, F And called block G. In one block, video and audio data of 15 Mbps are recorded for about 30 seconds. Further, B to G described below in FIG. 4 are indexes indicating the reproduction start positions in the tape longitudinal direction of the blocks B to G, respectively.
[0029]
In FIG. 4, it is assumed that the video and audio signals already recorded from block C to block E are mixed with another audio signal and recorded again at the original location. In this case, the operation will be specifically described.
[0030]
FIG. 5 is a timing chart for explaining the operation at this time. In FIG. 5, (a) indicates the position in the longitudinal direction of the tape at each time with an index indicating the reproduction start position described below in FIG. FIG. 5B shows the running state of the magnetic tape 2, “4 × speed playback” is a state in which edited data is played back from the magnetic tape 2 at 4 × speed, and “REW” is an average speed of about 6.5 times. In the high-speed rewind state in which the tape is rewound, “4 × speed recording” is a state in which editing data is recorded on the magnetic tape 2 at 4 × speed. (C) and (d) of FIG. 5 are graphs showing the amount of residual data that has not been read yet after being stored in the reproduction memory 101 and the recording memory 100, respectively. Further, (e) and (f) of FIG. 5 represent the contents of the signal 108 to be written and the signal 18 to be read, respectively, in the reproduction memory 101, and c, d and e shown in FIG. , Block D and block E are signals reproduced. 5 (g) and 5 (h) respectively represent the contents of the signal 20 to be written to the recording memory 100 and the signal 109 to be read, and c1, d1 and e1 are the blocks C, D and D in FIG. A signal obtained by mixing the signals c, d, and e reproduced from the block E with another signal, and a signal to be recorded at the positions of the block C, the block D, and the block E again. (I) in FIG. 5 shows the time when the operation start time is set to zero.
[0031]
First, it is assumed that the tape position is at the tape position C as shown in FIG. The control circuit 102 sends a control signal 107 instructing “4 × speed reproduction” to the tape drive circuit 15 and a control signal 106 instructing reproduction processing to the reproduction processing circuit 13. From the tape position C to the tape position D, the tape travels in the “4 × speed reproduction” state as shown in FIG. Block C and block D are recorded from tape position C to tape position D. As described above, the video and audio data of 15 Mbps are recorded in the block C and the block D, and the time to reach the tape position D to run in the “4 × speed playback” state is shown in FIG. It is time T2. During this time, the device is in a playback state. At this time, as shown in FIG. 5E, the signal 108 demodulated by the reproduction processing circuit 13 becomes the data c and d of the block C and the block D reproduced at 60 Mbps. The reproduction memory 101 sequentially stores the signal 108 during this time. As a result, as shown in FIG. 5C, the amount of residual data stored in the reproduction memory 101 and not read out increases. During this time, data stored at 15 Mbps is read from the playback memory 101 in the order in which it is stored. As shown in FIG. 5 (f), the data contents c of block C and block D are included in the signal 18. And d are output at 15 Mbps.
[0032]
When the control circuit 102 detects that the residual data in the reproduction memory 101 has reached a predetermined amount, it sends control signals 107, 106, and 105 to the tape drive circuit 15, reproduction processing circuit 13, and reproduction memory 101, respectively. Is stopped, and the reproduction process and the memory writing operation are interrupted.
[0033]
The signal 18 is mixed with another audio signal 110 by the mixing circuit 16 to become a signal 20. In this example, as shown in (i) of FIG. 5, it is assumed that time T1 is required for the processing during this period. For this reason, the signal c1 of the block C obtained by mixing the reproduction data c of the block C with the audio signal 110 is output from the mixing circuit 16 from time T1, as shown in FIG. 5 (g). The signal 20 is always stored sequentially in the recording memory 100 at 15 Mbps. For this reason, the amount of residual data that is stored in the recording memory 100 and not read out increases sequentially from time T1 to time T3 at which "4-times velocity recording" starts, as shown in FIG.
[0034]
When the control circuit 102 detects that the remaining data in the reproduction memory 101 has reached a predetermined amount at time T2, the control circuit 102 sends a control signal 107 instructing a rewind command to the tape drive circuit 15, and the tape running is “REW”. It becomes a state. Here, in FIG. 5B, the time T2 does not coincide with the start time of the “REW” state, but this is because the control circuit 102 detects that the remaining data in the reproduction memory 101 has reached a predetermined amount. This is because the rewind command is instructed and the 4 × speed reproduction is performed until the rewind starts. When the control circuit 102 detects that the output signal 108 of the reproduction processing circuit 13 has returned to the tape position C, the control circuit 107 causes the tape drive circuit 15 to stop rewinding. With this control, neither recording nor reproduction on the magnetic tape is performed from time T2 to time T3, but data is read continuously from the reproduction memory 101 at 15 Mbps, and the reproduction data of the signal 18 is There is no break. Further, the storage of the signal 20 at 15 Mbps in the recording memory 100 is performed without interruption. Data is continuously read from the reproduction memory 101 at 15 Mbps, and the data c of the block C appears continuously in the signal 18 as shown in FIG. The amount decreases as shown in FIG. Further, in the signal 20, the data c1 obtained by mixing the signal 110 in the mixing circuit 16 appears continuously as shown in FIG. 5 (g), and is continuously stored in the recording memory 100 at 15 Mbps. The amount of residual data in the main memory 100 increases as shown in FIG.
[0035]
Next, immediately after the “REW” state to the “stop” state, the control circuit 102 controls the tape drive circuit 15, the recording processing circuit 11, and the recording memory 100 with the control signals 107, 104, and 103 at time T3. As shown in FIG. 5B, the tape travel is set to the “4 × speed recording” state, and the tape travels in this state until the tape position D is reached at time T4 and the remaining amount of recording memory becomes zero. During this time, the apparatus is in a recording state on the magnetic tape 2 and is read in the order in which the data c1 is read out from the recording memory 100 at 60 Mbps. As shown in FIG. Data C1 of block C to be newly recorded appears at the tape position where C data c was recorded. This signal 109 is newly recorded from the beginning to the end recorded by the block C via the recording processing circuit 11. Since the data c1 is recorded at 60 Mbps, which is four times 15 Mbps, the recording of the block c1 including the video and audio data of 15 Mbps is completed in 1/4 time. Further, since the recording memory 100 reads data at 60 Mbps, the residual data amount in the recording memory 100 rapidly decreases as shown in FIG.
[0036]
Next, the control circuit 102 instructs the tape drive circuit 15 to perform “4 × speed reproduction” from the tape position D which is the previous reproduction end position, and the control signal 106 instructs the reproduction processing circuit 13 to perform reproduction processing. Send. From time T4 to time T5, as shown in FIG. 5B, the magnetic tape 2 runs again in the “4 × speed reproduction” state, and reaches the tape position E as shown in FIG. 5A at time T5. To do. During this time, the apparatus is in a reproduction state, and as shown in FIG. 5E, the signal d of the block D is output from the reproduction processing circuit 13 as a signal 108 of 60 Mbps and is sequentially stored in the reproduction memory 101 for reproduction. The residual data amount in the memory 101 increases again as shown in FIG. During this time, reading from the reproduction memory 101 is continuously performed at 15 Mbps, and the signal d of the block D is output as a signal 18 without interruption. During this time, as the signal 20, the data d1 of block D obtained by mixing the signal 110 with the signal of block D from time T4 as shown in FIG. The data is output and sequentially stored in the recording memory 100 at 15 Mbps.
[0037]
Next, at time T5, when the control circuit 102 detects that the remaining data in the reproduction memory 101 has reached a predetermined amount, it sends a control signal 107 instructing a rewind command to the tape drive circuit 15, and the tape running is shown in FIG. As shown in FIG. 5 (b), the state becomes the “REW” state, rewinds at a high speed, returns to the tape position D and stops. Here, in FIG. 5B, the time T5 does not coincide with the start time of the “REW” state, but this is because the control circuit 102 detects that the residual data in the reproduction memory 101 has reached a predetermined amount. This is because the rewind command is instructed at time T5, and the 4 × speed reproduction is performed until the rewind starts. During this time T5 and T6 when the tape is started next time, neither recording nor reproduction on the magnetic tape 2 is performed. However, during this time, as shown in FIG. 5 (f), data is read continuously from the reproduction memory 101 at 15 Mbps, and the reproduction data of the signal 18 is not interrupted. Further, as shown in FIG. 5D, the signal 20 is stored in the recording memory 100 at 15 Mbps without interruption.
[0038]
The control circuit 102 immediately controls the tape drive circuit 15, the recording processing circuit 11, and the recording memory 100 with the control signals 107, 104, and 103 at time T6 after the “stop” state from the “REW” state. As shown in (b), the tape running is set to the “4 × speed recording” state, and the tape is run in this state until the tape position E is reached at time T7 and the remaining amount of recording memory becomes zero. During this time, the apparatus is in a recording state on the magnetic tape 2, and data is read from the recording memory 100 at 60 Mbps in the order in which the data is stored. As shown in FIG. The data d1 of the block D appears as a signal 109 to be newly recorded at the tape position where has been recorded. This signal 109 is newly recorded from the beginning to the end where the block D was recorded via the recording processing circuit 11. Since recording is performed at 60 Mbps, which is four times 15 Mbps, the data d1 recording of the block D including video and audio data of 15 Mbps is completed in ¼ time. Further, since data is read out at 60 Mbps, the residual data amount in the recording memory 100 rapidly decreases as shown in FIG.
[0039]
By the operation so far, the signals c and d of the block C and the block D which have been recorded on the magnetic tape are again recorded in the original place as signals c1 and d1 obtained by mixing different audio signals. Thereafter, the reproduction, rewinding and recording processes are repeated in the same manner from the time T1 to the time T4. In order to perform the above operation, the recording memory 100 and the recording processing circuit 11 perform an intermittent reading operation and a recording processing operation by the control signals 103 and 104 from the control circuit 102, respectively. Further, the reproduction processing circuit 13 and the reproduction memory 101 perform intermittent reproduction processing operation and writing operation according to control signals 106 and 105 from the control circuit 102, respectively. Further, the tape drive circuit 15 controls the running of the magnetic tape according to the control signal 107 from the control circuit 102.
[0040]
Next, in the first embodiment of the present invention, the method of transition from the “4 × speed playback” state to the “REW” state in FIG. 5B and the “4 × speed recording” state from the “stop” state after REW. The method of shifting to will be described more specifically with reference to FIG.
[0041]
FIG. 6 is a graph showing the relationship between the movement of the tape and the remaining memory capacity in the first embodiment of the present invention. In FIG. 6, the Ta period indicates the “4 × speed playback” state, the Tb period indicates the “REW” state and the “stop” state, the Tc period indicates the “4 × speed recording” state, and the Td period indicates the “4 × speed idling” state. After the Td period, the same operation is repeated in the “4 × speed playback” state. The remaining memory capacity for reproduction shown in FIG. 6 represents the remaining memory capacity of the reproducing memory 101 in FIG. 1, and the remaining memory capacity for recording represents the remaining memory capacity of the recording memory 100 in FIG. Note that the initial increase start point of the reproduction memory remaining amount and the recording memory remaining amount is different by the time T1 in FIG. 5, but is ignored here as a minute time. Further, the normal reproduction virtual position in FIG. 6 represents the position on the tape of the data read from the reproduction memory at the normal speed. T2, T3, T3a, T3b, T4, and T4a indicate times when the operation start time is set to zero.
[0042]
Hereinafter, the relationship between the movement of the tape and the remaining amount of memory for reproduction will be described by taking the case where the memory for reproduction has a capacity of 4 Ta hours as an example. In the “4 × speed playback” state, as shown in the 4 × speed playback position in FIG. 6, playback data that is played back at 4 × speed with respect to the normal speed is written in the playback memory 101, and the normal playback virtual position in FIG. As shown, the reproduction data is read from the reproduction memory 101 at a normal speed. At this time, the edit data is written in the recording memory 100 at the normal speed as shown in the normal reproduction virtual position in FIG. The capacity of the reproduction memory 101 is filled with reproduction data for 4 Ta hours at time T2 after Ta time has elapsed from the start of reproduction. At this point, the writable remaining memory capacity of the playback memory 101 is 3 Ta time as shown in FIG. 6 because the playback data is read at the normal speed for Ta time. The reproduction memory 101 informs the control circuit 102 by the control signal 105 that the memory capacity is full, and the control circuit 102 prohibits writing of reproduction data to the reproduction memory 101 by the control signals 105 and 107, and the tape A command to shift to the “REW” state is issued to the drive circuit 15. Next, the control circuit 102 issues a “stop” command to the tape drive circuit 15 by the control signal 107 when the tape is rewound for 4 Ta hours, for example, by detecting TC from the reproduction signal 108 in the “REW” state. . Immediately thereafter, a “4 × speed recording” command is issued to the tape drive circuit 15 to shift to the “4 × speed recording” state.
As shown in FIG. 6, the period for performing “4 × speed recording” does not necessarily coincide with the time for performing “4 × speed reproduction”. As shown in FIG. 6, the writing of the edit data to the recording memory 100 at the normal reproduction speed is completed at time T4a. In order to complete the “4-times velocity recording” at the time T4a, from the time Tc to “4” “Double speed recording” can be started. However, since “4 × speed recording” is performed immediately after rewinding is completed, it may start from a time before time Tc. In this case, before writing of editing data at the normal playback speed is completed, “ The reading of “4 × speed recording” catches up. Therefore, the “4 × speed recording” state ends at time T3b when the remaining amount of the recording memory 100 becomes zero. Since the signal written in the recording memory 100 from the time 0 to the time T3b at the normal speed is read and recorded at a speed four times the writing in the period from the time T3 to the time T3b, the time from the time T3 to the time T3b is recorded. Assuming that the period up to T3b is Tc and the period of the “REW” state and the period of the “stop” state are Tb, there is a relationship of (Ta + Tb + Tc): Tc = 4: 1, and Tc = (Ta + Tb) / 3 Can be represented. At time T3b, the recording memory 100 informs the control circuit 102 by the control signal 103 that the remaining amount has become 0, and the control circuit 102 transmits the data from the recording memory 100 at the quadruple speed by the control signals 103 and 104. A command for prohibiting reading is issued, and the recording operation of the recording processing circuit 11 is prohibited. However, since reading of the data written in the reproduction memory 101 in “4 × speed reproduction” has not been completed, the 4 × speed operation of the tape by the tape drive circuit 15 is continued as it is and “4 × speed reproduction” is completed. The “4 × speed idling” state is continued until the Td period. In the period Td, the time for performing “4 × speed reproduction” and “4 × speed recording” is the same, and therefore Tc + Td = Ta, and can be expressed as Td = (2Ta−Tb) / 3. The period of the “4 × speed idling” state is related to the margin of the remaining memory for reproduction. In this case, the signal 20 is written in the recording memory 100 at the normal reproduction speed even after the “4 × speed recording” is completed at the time T3b, and the writing is completed at the time T4a after the period 4Td from the time T3b. . Therefore, 4Td−Td = 3Td, that is, the remaining amount of the reproduction memory 101 has a margin for 2Ta−Tb time. This margin is the remaining memory capacity of the reproduction data to be reproduced at the normal speed, and within this Td time range, it is possible to absorb the variation in the “REW” period and the variation in the timing for shifting to “4 × speed recording”. That is, it means that the control period in the “REW” state and the transition timing to the “4 × speed recording” state can be designed freely. The edit data written to the recording memory 100 after the time T3b is written from the previous recording end position at the next “4 × speed recording”.
[0043]
Also, in the after-roll function that checks video or audio after the OUT point continuously from the editing state, the amount of memory for playback is made larger than the amount of recording memory by the amount of after-roll, thereby reproducing the amount of after-roll after editing OUT. By always acquiring data, high-speed playback for after-roll in pre-roll editing is not necessary, and the processing can be simplified.
[0044]
As a result of the operation described above, the video and audio signals already recorded in block C to block E can be mixed with another audio signal and recorded again at the original location.
[0045]
As described above, in the present embodiment, recording on the magnetic tape and reproduction from the magnetic tape are alternately performed alternately at a data rate faster than the data rate of video and audio input or output. Without providing a reproducing head, a signal already recorded on the magnetic tape and another signal can be mixed and recorded again at the original location.
[0046]
Note that the storage capacities of the recording memory 100 and the reproducing memory 101 can be easily configured with a semiconductor memory. However, when a signal with a higher data rate is handled, the necessary storage capacity becomes large, and it becomes expensive to configure with a semiconductor memory. In this case, another storage medium such as a magnetic disk may be used for one or both memories. Thereby, a large-capacity memory can be configured at low cost.
[0047]
In the present embodiment, video and audio signals are recorded and reproduced intermittently at predetermined intervals of about 30 seconds. However, the present invention is not limited to this, and a shorter cycle or a longer cycle is used. You may make it carry out.
[0048]
In the present embodiment, the video and audio signals are intermittently recorded or reproduced at a rate four times the original data rate (N1 = N2 = 4). However, the present invention is not limited to this. It is sufficient that the rate is substantially more than twice as high as the average, and the recording and reproduction rates need not be the same. Specifically, if the read speed of the first memory is set to N1 (N1> 1) and the write speed of the second memory is set to N2, the setting is such that 1 / N1 + 1 / N2 <1. By selecting the amount of memory, the memory writing and reading operations do not fail during one round of operations from T1 to T4.
[0049]
In addition, the first memory and the second memory only need to be somewhere in the recording process and the reproduction process. In the case of a digital VTR that performs compression / decompression processing, the first memory (recording memory 100) is By inputting compressed editing data and decompressing the output of the second memory (playback memory 101), the amount of memory can be greatly reduced.
[0050]
Further, the first memory, the second memory, the mixing circuit, and the like may be configured by a memory on a computer and software processing using a personal computer or the like.
[0051]
(Embodiment 2)
Next, an information editing apparatus according to Embodiment 2 of the present invention will be described. The information editing apparatus according to the present embodiment is configured such that the same pre-read editing function can be realized with about half the memory amount by using one common ring memory on the recording side and the reproducing side. The head arrangement on the rotary cylinder in the present embodiment is exactly the same as the cylinder of the first embodiment shown in FIG.
FIG. 7 is a block diagram showing the configuration of the information editing apparatus of the present embodiment for editing an already recorded audio signal. In FIG. 7, blocks and signals having the same functions as those of the conventional example and the information editing apparatus of the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. In FIG. 7, 203 is a ring memory which is a storage device in which addresses are connected like a ring.
[0052]
In the present embodiment, the signal to be recorded is continuously written in the ring memory 203 at the first data rate, and is intermittently read out at the second data rate faster than the first data rate in the same order as the signal 109. This is given to the recording processing circuit 11. The signal input to the recording processing circuit 11 is subjected to shuffling processing, error correction coding, modulation, and the like, and is then supplied to the head switch 10 to be recorded on the magnetic tape at the second data rate. A signal reproduced at the second data rate by the reproducing heads 5 and 6 is given to the reproduction processing circuit 13 as a signal 22. The reproduction processing circuit 13 performs demodulation, error correction, and deshuffling processing on this signal, and applies it to the ring memory 203 and the control circuit 102 as a signal 108. The ring memory 203 intermittently records the signal 108 reproduced at the second data rate, continuously reads it at the first data rate in the recording order, and gives the read signal to the mixing circuit 16. The control circuit 102 alternately repeats the intermittent reproduction operation and the intermittent recording operation described above in the ring memory 203, the reproduction processing circuit 13, and the recording processing circuit 11 according to the control signals 205, 104, and 106, and in response to the control signal 107. The tape drive circuit 15 is controlled so that the magnetic tape is rewound at a high speed between the reproducing operation and the recording operation. The control circuit 102 receives the signal 108 reproduced from the magnetic tape and the address information 205 for each read / write of the ring memory, thereby grasping the running position of the tape and the memory state, and the timing of each control signal. Control. Here, the recording processing circuit 11, the head switch 10, and the heads 3 and 4 constitute recording means for intermittently recording data read from the memory on the magnetic tape 2. The reproduction processing circuit 13, the head switch 12, the heads 5, 6, and 6 constitute reproduction means for intermittently reproducing data from the magnetic tape 2 at the second data rate.
[0053]
Next, a more specific operation will be described with reference to FIG. Now, as in FIG. 4 of the first embodiment, each block is arranged on the magnetic tape 2, and another audio signal is mixed with the video and audio signals already recorded from the block C to the block E, and the original is again obtained. Shall be recorded at The operation in this case will be specifically described.
[0054]
FIG. 8 is a timing chart for explaining the operation at this time. In FIG. 8, (a) shows the position in the longitudinal direction of the tape at each time with an index described in the lower part of FIG. FIG. 8B shows the running state of the magnetic tape 2, “4 × speed reproduction” (N2 = 4) is a state in which data is reproduced from the magnetic tape 2 at 4 × speed, and “REW” is the next recording start position. The state in which the tape is rewound and the recording timing is awaited, “4 × speed recording” (N1 = 4) is a state in which data is recorded on the magnetic tape 2 at 4 × speed. FIG. 4C shows the positions of the write address R and read address S during recording, the write address P and read address Q during reproduction on the ring memory, respectively. Further, FIG. 8E shows the signal 108 to be written to the ring memory 203, and FIG. 8F shows the contents of the signal 18 read from the ring memory 203 and converted into the data rate. , E indicate the signals reproduced from block C, block D, and block E of FIG. 4G shows the signal 20 to be written to the ring memory 203, and FIG. 4H shows the contents of the signal 109 read from the ring memory 203. c1 and d1 are the blocks C and D in FIG. 4, respectively. A signal obtained by mixing another signal with the signal reproduced from Fig. 4 represents a signal to be recorded at the positions of block C and block D again. FIG. 4I shows the time from the operation start time.
[0055]
First, it is assumed that the tape position is at the tape position C as shown in FIG. At time 0, the write address R and read address S at the time of recording, the write address P and the read address Q at the time of reproduction are reset to 0 on the ring memory 203. The control circuit 102 sends a control signal 107 to the tape drive circuit 15 and a control signal 106 to the reproduction processing circuit 13 until the tape reaches the tape position D from the tape position C as shown in FIG. Drive in "4x speed playback" state. Block C and block D are recorded from tape position C to tape position D. As described above, the video and audio data of 15 Mbps are recorded in the block C and the block D, and the time to reach the tape position D to run in the “4 × speed playback” state is shown in FIG. It is time T2. During this time, the device is in a playback state.
[0056]
From time T1 to time T2, as shown in FIG. 8C, the address P at which the reproduction signal 108 is written to the ring memory 203 is four times faster, the read address Q, and the write address R at the time of recording. Goes around the ring at a speed of 1 ×, and the playback operation ends at time T2 when the write address P catches up with the read address S. Specifically, the control circuit 102 detects that the difference between the address P and the address S has become equal to or less than a predetermined value, and sends control signals 107, 106, to the tape drive circuit 15, the reproduction processing circuit 13, and the ring memory 203, respectively. 105 is sent to interrupt the playback operation. The signal 18 read from the ring memory 203 is mixed with another audio signal 110 by the mixing circuit 16 to become a signal 20. As shown in FIG. 8, in this embodiment, it is assumed that T1 is required for the processing during this time. Therefore, the data c1 obtained by mixing the signal 110 with the reproduction data of the block C is output as the signal 20 from the mixing circuit 16 from time T1, as shown in FIG. The signal 20 is sequentially stored in the ring memory 203. For this reason, the write address R at the time of recording increases sequentially from the time T1 with an address difference of only the read address Q on the reproduction side and T1.
[0057]
From time T2 to time T3, the control circuit 102 sends a rewind command to the tape drive circuit 15 by the control signal 107 to set the tape running to the “REW” state. Here, in FIG. 8B, the time T2 and the start time of the “REW” state do not coincide with each other. However, this means that the control circuit 102 detects that the tape position D has been reached, and issues a rewind command. This is because the instruction is given and 4 × speed reproduction is performed until rewinding starts. When the control circuit 102 detects the tape position C from the output signal 108 of the reproduction processing circuit 13, the control circuit 107 causes the tape driving circuit 15 to stop the tape running. During this time, neither recording nor reproduction on the magnetic tape 2 is performed. However, during this time, the signal 18 is continuously read from the ring memory 203 at the first data rate (for example, 15 Mbps) and is not interrupted. Further, the signal 20 is continuously stored in the ring memory 203.
[0058]
After the “REW” state to the “stop” state, the control circuit 102 immediately controls the tape drive circuit 15, the recording processing circuit 11, and the ring memory 203 with the control signals 107, 104, and 205 at time T3. As shown in b), the tape travel is set to the second data rate (for example, 60 Mbps in the case of quadruple speed recording), and the tape travels in this state until reaching the tape position D at time T4 and there is no data to be recorded. During this time, the apparatus is in a recording state on the magnetic tape 2 and is read out in the order in which data is read from the ring memory 203 at the second data rate. As shown in FIG. As a result, data c1 to be newly recorded appears at the tape position where the block C was recorded. This signal 109 is newly recorded from the beginning to the end recorded by the block C via the recording processing circuit 11. In this example, since recording is performed at 60 Mbps, which is four times 15 Mbps, recording of data c1 including video and audio data of 15 Mbps is completed in ¼ time.
[0059]
From time T3 to time T4, as shown in FIG. 8C, the address S at which the signal to be recorded on the magnetic tape 2 is read is four times faster, the read address Q, and the write address R at the time of recording. Goes around the ring at a single speed, and the recording operation ends at time T4 when the address S catches up with the edit data write address R. At time T4, the control circuit 102 controls to increase the tape speed to quadruple speed, and when the next data of the reproduction data written in the previous memory is detected by the signal 108 output from the reproduction processing circuit 13, the tape is started from the reproduction timing T4. The “4 × speed reproduction” state is reached again, and the tape position E is reached at time T5 as shown in FIG. During this time, as shown in FIG. 8E, the signal d of the block D appears in the signal 108 at 60 Mbps and is sequentially stored in the ring memory 203. During this time, reading from the ring memory 203 is continuously performed, and the signal d of the block D appears in the signal 18 without interruption. Further, as shown in FIG. 8 (g), data d1 obtained by mixing the signal 110 with the signal of block D from time T4 appears continuously at 15 Mbps in the signal 20, and is sequentially stored in the ring memory 203. To go. Thereafter, similarly, the reproduction, rewinding, and recording processes are repeated in the period from time T1 to T4. In order to perform the above operation, the ring memory 203, the reproduction processing circuit 13, and the recording processing circuit 11 operate according to control signals 205, 106, and 104 from the control circuit 102. Further, the tape drive circuit 15 controls the running of the magnetic tape according to the control signal 107 from the control circuit 102.
[0060]
Next, in the second embodiment of the present invention, the method of transition from the “4 × speed reproduction” state to the “REW” state in FIG. 8B and the “stop” state after the REW to the “4 × speed recording” state. The method of shifting to will be described more specifically with reference to FIG.
[0061]
FIG. 9 is a graph showing the relationship between the movement of the tape and the memory address in the second embodiment of the present invention. In FIG. 9, the Ta period indicates the “4 × speed playback” state, the Tb period indicates the “REW” state and the “stop” state, the Tc period indicates the “4 × speed recording” state, and the Td period indicates the “4 × speed idling” state. After the Td period, the same operation is repeated in the “4 × speed playback” state. The memory address (accumulated value) represents the address of the ring memory 203 in FIG. 7. The address P is the write address of the reproduction data 108 at 4 × speed, the address Q is the read address of the reproduction data 18 at the normal speed, and the address S is 4 × speed. The read address and the address R of the edit data 109 indicate the write address of the normal speed edit data 20. The address Q and the address R are different by the time T1 in FIG. 8, but are ignored here as a minute time. 9 represents the position on the tape of the data read from the ring memory 203 at the normal speed. T2, T3, T3a, T3b, T4, and T4a indicate times when the operation start time is set to zero.
Hereinafter, the movement of each address will be described by taking as an example that the ring memory 203 has a capacity for 4 Ta hours. In the “4 × speed reproduction” state, the reproduction data reproduced at the quadruple speed with respect to the normal speed is written in the ring memory 203, and the reproduction data is read from the ring memory 203 at the normal speed. At this time, edit data is written in the ring memory 203 at a normal speed. In the period of “4 × speed reproduction” state, the address P goes around the ring of the ring memory 203 for 4 Ta hours in Ta time and returns to the initial position. At this time, since the reproduction data is read from the address Q of the ring memory 203 at a normal speed, the difference between the address P and the address Q is 3 Ta hours as shown in FIG. The control circuit 205 informs the control circuit 102 that the address P has made a round on the ring of the ring memory 203 and has returned to the initial position, and the control circuit 102 uses the control signals 205 and 107 to reproduce the quadruple speed to the ring memory 203. Data writing is prohibited and a command to shift to the “REW” state is issued to the tape drive circuit 15. Next, the control circuit 102 issues a “stop” command to the tape drive circuit 15 by the control signal 107 when the tape is rewound for 4 Ta hours, for example, by detecting TC from the reproduction signal 108 in the “REW” state. . Immediately thereafter, the control circuit 102 issues a “4 × speed recording” command to the tape drive circuit 15 and shifts to the “4 × speed recording” state. The “4 × speed recording” state continues until the edit data is read from the ring memory 203 at 4 × speed and the address S catches up with the address R. This period Tc can be expressed as Tc = (Ta + Tb) / 3, as in the first embodiment, when the period of the “REW” state and the period of the “stop” state are combined as a Tb period. The control signal 205 informs the control circuit 102 that the address S has caught up with the address R, and the control circuit 102 issues a command for prohibiting reading of the edit data at 4 × speed from the ring memory 203 by using the control signals 205 and 104, and recording. The recording operation of the processing circuit 11 is prohibited. As in the first embodiment, when “4 × speed recording” catches up with reading of normal speed reproduction data, the tape drive circuit 15 continues the 4 × speed operation of the tape until “4 × speed reproduction” ends. The “4 × speed idling” state is continued for the Td period. This period Td can be expressed by Td = (2Ta−Tb) / 3, and the period of the “4 × speed idling” state is related to the margin of the difference between the address P and the address Q on the ring memory 203, In this case, it is shown that there is a margin in the difference between the address P and the address Q by 2Ta-Tb time. This is the remaining memory capacity for outputting the reproduction data at the normal speed, and it is possible to absorb the variation in the “REW” period and the variation in the timing of shifting to “4-times velocity recording” within the Td time range. In other words, it is possible to increase the degree of freedom in designing the “REW” state and the timing for shifting to “4 × speed recording”. The edit data written to the ring memory 203 after the time T3b is written at the next “4 × speed recording”. In this case, the magnetic tape 2 is rewound to the previously unrecorded head position.
[0062]
As a result of the operation described above, the video and audio signals already recorded in block C to block E can be mixed with another audio signal and recorded again at the original location.
[0063]
As described above, in this embodiment, recording on the magnetic tape and reproduction from the magnetic tape are alternately performed at a data rate higher than the data rate of video and audio, without providing a preceding reproducing head, A broadcast digital VTR having a function of mixing a signal already recorded on the magnetic tape with another signal and recording it again at the original location can be realized. Further, by adopting a ring memory configuration for the recording and reproducing memories, it is possible to realize with about half the amount of memory compared to the first embodiment.
[0064]
Note that the storage capacity of the ring memory 203 can be easily configured with a semiconductor memory. However, when a signal with a higher data rate is handled, the required storage capacity is increased and the cost may be increased. In this case, another storage medium such as a magnetic disk may be used. Thereby, a large-capacity memory can be configured at low cost.
[0065]
In this embodiment, the video and audio signals are intermittently reproduced and recorded at four times (N1 = 4) at the four times (N2 = 4) of the original data rate. The rate is not limited, and any rate that substantially exceeds the average two times the original data rate may be used. Further, although the original data rate is 15 Mbps, it is not limited to this.
[0066]
Further, in the present invention, the already recorded signal and another signal are mixed and recorded again at the original location. However, the present invention is not limited to this, and the already recorded signal is processed. In this case, the recording may be performed again in the original location, or only part of the track may be rewritten (for example, only the audio area may be partially rewritten).
[0067]
In the present invention, the predetermined amount of reproduction data written is set to a capacity of 4 Ta hours, and the predetermined amount of edit data remaining read from the memory is set to 0. However, the present invention is not limited to this.
[0068]
In the present invention, an example of a broadcast D-VTR is shown, but the present invention is not limited to a digital VTR. For example, it goes without saying that the present invention is also applicable to the case where the first memory and the second memory are configured by an optical disk, a hard disk, or the like.
[0069]
【The invention's effect】
As is apparent from the above description, according to the present invention, without providing a preceding reproducing head, a signal that has already been recorded and another signal are mixed and recorded again at the original location, or an already recorded signal. It is possible to provide an information editing device having a pre-read editing function for processing and recording again in the original place.
[0070]
Further, in the pre-read editing method of the present invention, when the high-speed prefetched data is written in the memory and exceeds a predetermined amount, the transition from high-speed prefetch to rewind is performed, and after rewinding, high-speed after-recording is performed to perform post-recording data. Is read from the memory and when it becomes less than or equal to the predetermined amount, the high-speed after-recording is terminated, and a series of operations in which the high-speed pre-reading is performed again after running idle. This idle running period can absorb variations in rewinding time and timing of transition to high-speed after-recording, and has the effect of increasing the degree of freedom in design.
[0071]
Furthermore, by making the amount of data stored in the memory for reproduction larger than the amount of data stored in the memory for recording, it is not necessary to perform a high-speed look-ahead operation specially for afterroll, and the processing can be simplified.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an information editing apparatus according to a first embodiment of the present invention.
FIG. 2 is a head arrangement diagram on a rotating cylinder according to the first embodiment of the present invention.
FIG. 3 is a diagram showing a positional relationship between a recording track pattern on a magnetic tape and a head in Embodiment 1 of the present invention.
FIG. 4 is a diagram showing a recording state on a magnetic tape.
FIG. 5 is a timing chart for explaining the operation of the first embodiment of the present invention.
FIG. 6 is a graph showing the relationship between the movement of the tape and the remaining memory capacity in the first embodiment of the present invention.
FIG. 7 is a block diagram showing a configuration of an information editing apparatus according to a second embodiment of the present invention.
FIG. 8 is a timing chart for explaining the operation of the second embodiment of the present invention.
FIG. 9 is a graph showing the relationship between tape movement and memory address in Embodiment 2 of the present invention;
FIG. 10 is a diagram showing a head arrangement on a rotary cylinder of a conventional information editing apparatus.
FIG. 11 is a diagram showing a positional relationship between a recording track on a magnetic tape and a head in a conventional information editing apparatus.
FIG. 12 is a block diagram showing a configuration of a conventional information editing apparatus.
FIG. 13 is a timing chart for explaining the operation of a conventional information editing apparatus.
[Explanation of symbols]
1 Rotating cylinder
2 Magnetic tape
3,4 recording head
5,6 Playback head
10, 12 Head switch
11 Recording processing circuit
13 Reproduction processing circuit
15 Tape drive circuit
16 Mixing circuit
100 memory for recording
101 Memory for playback
102 Control circuit
203 ring memory

Claims (7)

A tape driving means for driving the magnetic tape;
Reproducing means for reproducing reproduction data from the magnetic tape driven by the magnetic tape driving means at a second transfer speed higher than that during normal reproduction ;
A second memory for writing and continuously reading the reproduction data reproduced by the reproduction means;
A first memory for continuously writing and reading edit data obtained by performing editing such as mixing other signals to the data read from the second memory;
Recording means for recording on the magnetic tape driven by the magnetic tape drive means at a first transfer speed higher than that during normal recording until the amount of data remaining in the first memory is equal to or less than a predetermined amount; ,
Control means for controlling operations of the tape driving means, the reproducing means, the second memory, the first memory, and the recording means,
The control means reproduces the magnetic tape at the second transfer speed until the write amount of the reproduction data in the second memory reaches a predetermined amount, and then rewinds the magnetic tape to a desired position. the first of said magnetic tape data amount remaining in the memory after the recording on the magnetic tape by the decreased below a predetermined amount the first transfer rate, up to continue before Symbol playback is completed position after allowed to run empty, yet the reproduction at the second transfer rate, the unwinding, all of the records in the first transfer rate, before sequentially repeated so that each means a run Kisora, or one An information editing apparatus characterized by controlling a section. 2. The information editing apparatus according to claim 1, wherein the amount of data stored in the second memory is larger than the amount of data stored in the first memory. 1 / N1 + 1 / N2 <1 when the reading speed of the first memory is N1 (N1> 1) double speed during normal recording and the writing speed of the second memory is N2 (N2> 1) double speed during normal reproduction. The information editing apparatus according to claim 1, wherein: 2. The information editing apparatus according to claim 1, wherein the first memory and / or the second memory is a magnetic disk. 2. The information editing apparatus according to claim 1, wherein the first memory and the second memory comprise one storage device for writing and reading edited data and for writing and reading reproduced data. 6. The information editing apparatus according to claim 5, wherein the storage device is a ring memory. 6. The information editing apparatus according to claim 5, wherein the storage device is a magnetic disk.

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