JP3448961B2 - Video signal processing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus having a function of compressing / decompressing a moving image in the process of recording / editing / reproducing a video signal, and by using an apparatus capable of randomly accessing those storage media, video production. The present invention relates to a video signal processing device capable of increasing the efficiency of the above.

[0002]

2. Description of the Related Art The applicant of the present invention filed Japanese Patent Application Laid-Open No. 58-164071.
There is proposed a video signal editing switcher for switching a plurality of video signals to produce one program, as described in Japanese Patent Laid-Open Publication No. Hei. This video signal editing switcher uses a special mark generator to add various effects to be inserted at the edit point of a video tape by adding a simple mark signal generator composed of a digital circuit. Since it is possible to suggest without an instruction and make the editor recognize, it is possible to reduce the cost of the editing device.

First, the proposed video signal editing switcher will be described with reference to FIG. Two video signals are supplied from the VTRs 51 and 52 to the switcher 56 of the editing machine 53, and the switcher 56 displays the video signal supplied to the monitor 54 for editing. The edited result is supplied to the VTR 55 and recorded. Here, the VTRs 51, 52, and 55 and the switcher 56 are the controller 57 included in the editing machine.
Is controlled by. However, this system has a problem that it takes time because the preroll is repeated in the VTRs 51 and 52 many times to determine the edit point.

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a video signal processing device capable of reproducing an edit point to be edited and edited in a short time.

Another object of the present invention is to provide a video signal processing device capable of encoding and decoding only a video which is edited and processed, that is, only a frame or a field.

[0006]

DISCLOSURE OF THE INVENTION The present invention has a disc-shaped medium which has an encoding means for compressing a plurality of frames of a video signal as a unit and which can randomly access the compressed video signal. And a plurality of compressed video signals recorded on the disk-shaped medium are edited in frame units, the first and second compressed video signals read out at substantially the same time are decoded. And first and second decoding means for switching, and switching means that is connected to the first and second decoding means and switches the first and second compressed video signals at edit points. The encoding means re-encodes only the video signal in the range where the editing point affects the decoding, and the edited compressed video signal is recorded on the disk-shaped medium. Video signal processing It is the location.

[0007]

When the edit processing is performed on a plurality of coded video signals, only the video signal subjected to the edit processing is decoded, and the edited video signal is processed. Done. Only the video signal in the vicinity of the edit point is encoded, and is recorded in a memory or at a different address from the original compressed video signal. Then, by the address control, it is controlled by the controller so as to be continuous as one video signal. As a result, the decoding and the coding are performed on the minimum range, so that the deterioration caused by the decoding and the coding can be minimized.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a block diagram of an example of a video signal processing device, and an example of editing processing is cut editing. A video signal is supplied from the digital VTR 1 to the video storage / playback apparatus 2. The video signal from the digital VTR 1 is supplied to the MPEG decoder 6 of the video storage / playback apparatus 2, and the supplied video signal is MPEG2 (Mo
ving Picture imagecoding Experts Gruop phase 2)
Encoding is performed based on the format.

The MPEG encoder 6 supplies the encoded or compressed video signal to the HDD 7, and the HDD 7 writes the compressed video signal in the transport stream format. In this way, a plurality of compressed video signals are written in the HDD 7, and the controller 13 stores the addresses of the written compressed video signals. According to the instruction from the controller 13, the two compressed video signals read from the HHD 9 are supplied to the MPEG decoders 8 and 10 and decoded. At this time, the decryption is performed only on the range to be edited.

The video signals decoded by the MPEG decoders 8 and 10 are stored in the frame memory 9,
And 11 and are stored frame by frame. A synchronization signal for supplying the video signal stored in the frame memories 9 and 11 to the switcher 12 is supplied from the timing control circuit 14 to the frame memories 9 and 11. The video signals output from the frame memories 9 and 11 are switched on a frame-by-frame basis, and effects such as wipe and fade-in / out are detected by the switcher 12 before and after the switched frame.
Made in.

In the switcher 12, the controller 13 gives an instruction as to which of the monitor 3, the output terminal 4 and the MPEG encoder 6 the supplied video signal is to be output. Here, the video signal is output to the external device via the output terminal 4. The video signal supplied from the switcher 12 to the MPEG encoder 6 is encoded again, and as described above, the compressed video signal is written and held in the HDD 7 in the transport stream format. Here, the device to which the compressed video signal is written is H
Although referred to as DD, MO (Magneto Opties), semiconductor memory, or the like can be used as long as it can be randomly accessed and can supply data to the MPEG decoder in the subsequent stage without interruption. .

Here, the syntax of the MPEG2 bit stream will be described. MPEG2 is a sequence (Se q u
ence), GOP (Group Of Picture), picture (Pict
ure), slice (Slice), macroblock (Macrobl
ock) and a block (Block). The block is composed of 8 pixels × 8 pixels of a luminance signal or a color difference signal, and has a DCT (Discrete Cosine)
Transfrom) unit. The macro block is composed of four luminance signal blocks and two color difference signal blocks.
It is composed of blocks and is a unit of motion compensation.

A slice is a series of images in the scanning order,
Alternatively, it is composed of a plurality of macroblocks and is a reset unit when an error occurs. A picture is composed of at least one or a plurality of slices, and is an I picture (Intra-coded).
Picture), P picture (Predictive coded Pictur)
e), B picture (Bi-directionally predictive coded
Picture), D picture (DC component of DCT output) 4
There are types. Further, the picture can be selected from a frame structure and a field structure. GOP is USP
As described in 4969055, it is composed of one or a plurality of I pictures and 0 or a plurality of P pictures and B pictures. A sequence consists of one or more GOPs.

An I picture indicates an image that has been subjected to intraframe / intrafield coding, and no motion compensation is used at this time. The P picture indicates an image which has been subjected to inter-frame / inter-field coding and which has been motion-compensated and predicted from the previous image. For a B picture, a motion vector is obtained by using images in both the front and rear directions. Therefore, at the time of decoding, motion compensation is performed by using two motion vectors and two (previous and subsequent) reference images.

FIG. 2 is a schematic diagram showing an example of a GOP and each picture. The decoding process will be described with reference to FIG. In this example, the GOP is composed of 10 pictures, and the I picture is first decoded. A P picture is predicted from the I picture and a P picture is generated. Further, a P picture is generated from the generated P picture. Next, two B pictures are generated from the I picture and P picture, and two B pictures are generated from the two P pictures.
A picture is generated. Also, two B pictures are generated from P pictures and I pictures included in different GOPs, and two B pictures are generated from different I pictures and P pictures. That is, I included in the preceding and following GOPs
A B picture is generated by using a picture or a P picture. As shown in FIG. 2, all frames belong to any GOP.

Here, FIG. 3 is a schematic view showing an example when the compressed video signals A and B are edited. First, in order to confirm the contents of the compressed video signals A and B, the compressed video signals A and B are read from the HHD, the read compressed video signals are decoded, and they are confirmed on a monitor. Then, the edit point is determined and the preview is performed. From the editing point of GOP-A2 of the compressed video signal A, G of the compressed video signal B
It is assumed that editing is performed so as to be continuous with the edit points of OP-B3.

However, since the MPEG coding is a hybrid coding method combining intra-frame compression (DCT) and motion compensation inter-frame prediction, the video cannot be reproduced by simply coding only the video to be edited. there is a possibility.

FIG. 4 is a simplified diagram for explaining the editing in detail. GOP-A2 5I frame and GOP-
The case where the 10B frame of B3 is connected is shown. G
The 3B and 4B frames of OP-A2 are 2 of GOP-A1.
GOP-A has been coded due to bidirectional prediction error from the P frame and the 5I frame of GOP-A2.
In order to decode 2B 3B and 4B frames, first, HD
GOP-A1 is read from D and decoded by the decoder.

On the other hand, since the 10B and 11P frames of GOP-B3 can be decoded from the 5I frame of the same GOP-B3, GOP-B3 is read from the HDD and decoded by the other decoder. After the 5I frame of GOP-A2 in the frame memory of the latter stage of the decoder, GOP-B
The switcher is switched so that the 3 10B frame is reproduced.

3B, 4B, 5 decoded by this
The I, 10B, 11P, 12B, 13B, and 14I frames are again supplied to the encoder, and the supplied 3B, 4B, and 5
Recording is newly made from the I, 10B, and 11P frames to the HDD as GOP-C1. In addition, 1 of GOP-C1
The 1P frame and the 13B and 12B frames of GOP-B4, which are encoded by the bidirectional prediction error from the 14I frame of GOP-B4, have their data stored in the file D1.
As a result, the controller records
The sequence is stored.

At the time of reproduction, the controller reads G from the HDD.
The editing result can be reproduced by reading in the order of OP-A1, GOP-C1, and GOP-B4 (however, the 12B and 13B frames of this GOP-B4 are read from the D1 file). Here, the controller stores the address of the compressed video signal recorded in the HDD, the storage of the determined edit point, and the GOP including the edit point.
Is reproduced and the edited result is encoded, then the addresses of the edited compressed video signals recorded in the HDD can be stored, and the reproduction order can be stored by storing these addresses.

Although the cut editing has been described here, the same configuration can be applied to the case where the effect is made on the editing point. That is, in FIG. 4, the 5I frame of the compressed video signal A is wiped to the 10B frame of the compressed video signal B,
When edit processing such as dissolve is performed, GOP-A2 of compressed video signal A and GOP of compressed video signal B from HDD
-B3 is read out at the same time and decoded into frame data by a decoder, and compressed video signals A and B 6B, 7B, 8
The P and 9B frames are combined by the switcher in the subsequent stage.
The resulting frames are 6B ', 7B', 8P
'And 9B' frames make it 3B, 4B, 5I frames of GOP-A2 and 6B ', 7B', 8P ',
A new GOP-C2 is created by the 9B ′ frame and the 10B and 11P frames of GOP-B3. The sequence during reproduction is the same as in the case of cut editing.

Here, in FIG. 5, the input video signal is changed to H
It is a flow chart which shows an example which records on DD. 21
The operation starts from the step indicated by
In PEG encoding, MP is applied to the input video signal.
Encoding is performed in the format of EG2. That is,
The control moves to step 23 for the compressed video signal. In the file writing in step 23, the supplied compressed video signal is written in the HDD. At this time, writing is performed in the HDD based on the format of the transport stream under the control of the controller.

In step 23 (file writing), the compressed video signal is written in the HDD, and then control is passed to step 24. In the file management in step 24,
The controller stores the address of the compressed video signal written in the HDD and manages it as a file. After step 24 (file management), control is transferred to step 25, and this flowchart ends.

Here, FIG. 6 is a flow chart showing an example of the editing process according to the present invention. This control is started from the step indicated by 31, and in the reading of the file A in step 32, the GOP of the compressed video signal A including the edit point is read from the HDD by the control of the controller. The read GOP is decrypted in the file A decryption in step 33. When reading the file B in step 34, the controller controls
The GOP of the compressed video signal B including the edit point is read from the HDD. In step 34 (reading of file B), control is performed substantially at the same time as step 32 (reading of file A).

Similarly, in the file B decoding at step 35, the GOP read at step 34 (reading file B) is decoded. In the editing / encoding of step 36, the decoded video signal is switched between the file A and the file B at the editing point and edited. After the editing process is completed, the edited image signal is supplied to the encoder, encoded, and the control proceeds to step 37.

In writing the file C in step 37,
In step 36 (editing / encoding), the edited and processed compressed video signal is newly written in the HDD as the file C. In the file management of step 38, in step 37 (writing of file C), the playback order of GOP is stored in the controller with the file C written in the HDD as the edit list, control is passed to step 38, and this flowchart ends. .

Here, FIG. 7 is a flow chart showing an example of the reproduction operation of the edited video signal. This control starts from the start of step 41
In reading the file, the controller reads GOPs from the HDD in the order of the edit list. In the decoding of step 43, the compressed video signal is decoded in the order of the read GOP and reproduced as a video signal. Step 44
At the end of, the control of the reproduction operation ends.

Here, FIG. 8 shows a schematic block diagram when the user uses the edited compressed video signal.
N monitors and N terminals 49 corresponding to the monitors 48 are connected to the video signal processing device 2. That is, the video signal processing device 2 is provided with N-channel input / output terminals. Here, in the video signal processing device 2, the compressed video signal edited as described above is MPEG-encoded for compression and recorded in the HDD included in the video signal processing device 2. A plurality of compressed video signals are recorded in the video signal processing device 2, and a selection signal is supplied from the terminal 49a to the video signal processing device 2 in order to watch one compressed video signal from the plurality of recorded compressed video signals. To be done.

The video signal processing device 2 outputs the compressed video signal corresponding to the supplied selection signal to the monitor 48a. The monitor 48a outputs the image to the screen after the supplied compressed image signal is decoded. Similarly, the selection signal is supplied from the terminal 49b, the compressed video signal is supplied to the monitor 48b, and the video is projected after being decoded. Here, the number of channels is determined so that even if the selection signals are simultaneously supplied to the video signal processing device 2 from all terminals, the compressed video signals can be supplied to any of the monitors without interruption.

[0031]

According to the present invention, it is possible to shorten the time required to repeat the pre-roll of the determined edit point of the video signal to be edited and the preview operation.

Further, according to the present invention, since the decoding and coding are performed and the editing processing is performed only on the range including the editing point of the compressed video signal in which the editing point is determined, the decoding, And the degradation due to the effect of coding is minimized.

Further, according to the present invention, since editing processing by the MPEG format is possible, the data handling cost of the entire system can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of a video signal processing device of the present invention.

FIG. 2 is a schematic diagram showing an example of a GOP and each picture of the present invention.

FIG. 3 is a schematic diagram used for explanation when editing a compressed video signal according to the present invention.

FIG. 4 is a schematic diagram in which editing of a compressed video signal according to the present invention is used for detailed description.

FIG. 5 is a flowchart showing an example of recording a video signal according to the present invention in an HDD.

FIG. 6 is a flowchart showing an example of editing processing according to the present invention.

FIG. 7 is a flowchart showing an example of a reproducing operation of a compressed video signal according to the present invention.

FIG. 8 is a flowchart showing an example of a video server according to the present invention.

FIG. 9 is a block diagram showing an example of a conventional video signal editing switcher.

[Explanation of symbols]

1 Digital VTR 2 Video storage and playback device 3 monitors 5 Input device 6 MPEG encoder 7 HDD 8, 10 MPEG decoder 9, 11 frame memory 12 switchers 13 Controller 14 Timing control circuit

Claims (6)

(57) [Claims] 1. A unit having an encoding unit for compressing a plurality of frames of a video signal as a unit, a unit for recording the compressed video signal on a randomly accessible disc-shaped medium, and recording on the disc-shaped medium. When editing the plurality of compressed video signals thus generated in frame units, first and second decoding for decoding the first and second compressed video signals read out substantially at the same time. Decoding means and switching means connected to the first and second decoding means and for switching the first and second compressed video signals at edit points, wherein the edit points are decoded To only the video signal in the range that affects
A video signal processing device, which serves as means for recording the edited compressed video signal on the disk-shaped medium. 2. The video signal processing device according to claim 1 , further comprising means for storing an address of a compressed video signal recorded on a disk-shaped medium, and further an edited compressed video recorded on the disk-shaped medium. A video signal processing apparatus comprising: a unit for storing an address of a signal; and a unit for reproducing the edited compressed video signal by using the stored address. 3. The video signal processing apparatus according to claim 1, wherein the encoding for compressing the video signal is MPE.
A video signal processing device using G2. 4. A means for recording the compressed video signal on a disc-shaped medium which can be randomly accessed , having an encoding means for compressing a plurality of frames of the video signal as a unit, and recording on the disc-shaped medium. When editing the plurality of compressed video signals thus generated in frame units, first and second decoding for decoding the first and second compressed video signals read out substantially at the same time. Decoding means and switching means connected to the first and second decoding means and for switching the first and second compressed video signals at edit points, wherein the edit points are decoded To only the video signal in the range that affects
A video signal processing device, characterized in that means for recording the edited compressed video signal on the disk-shaped medium, and for reading out the edited compressed video signal from the disk-shaped medium and sending it to the outside. 5. The video signal processing device according to claim 4.
There are, the address of the compressed video signal recorded on the disk-like medium
Means for storing, and further, the edited pressure recorded on the disc-shaped medium.
A means for storing the address of the compressed video signal, and a means for storing the compressed video signal that has been edited.
And means for playing back using the above address
A video signal processing device characterized by the above. 6. The video signal processing device according to claim 4.
The encoding for compressing the video signal is performed by MPE
A video signal processing device using G2.