JP2005311636A - Recording/reproducing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive recording/reproducing device without degradation of images even when a plurality of images are simultaneously recorded. <P>SOLUTION: A plurality of video signals synchronized with a frame synchronizer 1 are synthesized to one composite video signal by a synthesizing circuit 2 and encoded with an MPEG encoder 3. After that, the signal is formatted to a format that it is the synthesized video signal with a format circuit 4 and recorded in a recording medium 5. When the signal is synthesized with a synthesizing circuit 2, it is synthesized at an image size larger than the total image size of a plurality of the video signals as a synthesizing target. When the signal is reproduced, the format of the recording medium 5 is decoded with a format decoding circuit 6. It is determined whether the synthesized video signal is read out or not. The video signal, which is arbitrarily designated from among the synthesized video signals decoded with an MPEG decoder circuit, is separated with a separating circuit 8 and outputted. The image size of the video signal separated with the separating circuit 8 is set to the same size as the image size of the video signal when the signal is synthesized with the synthesizing circuit 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a recording / reproducing apparatus, and more particularly to a technique for simultaneously recording and reproducing a plurality of videos in a recording / reproducing apparatus using an optical disc as a recording medium.

In order to record a plurality of video signals simultaneously with a recording / reproducing apparatus (for example, a DVD recorder) using an optical disk, a method using a plurality of MPEG encoders or Japanese Patent Application Laid-Open No. 2003-102009 disclosed in Japanese Patent Application Laid-Open No. 2003-102009 is disclosed. A technique of compressing a plurality of video signals in the horizontal direction and the vertical direction described in “Channel Video Signal Encoding Device and Method” and outputting the compressed video signals as one video signal is known.
JP 2003-102009 A

However, the method using a plurality of MPEG encoders as in the conventional method has a complicated system, and a cost problem remains as a consumer AV device.
In addition, as in the above-mentioned Patent Document 1, in a method that simply uses horizontal compression synthesis and vertical compression synthesis, degradation of image resolution becomes a problem.
The present invention has been made to solve such a problem, and an object of the present invention is to provide a recording / reproducing apparatus that does not deteriorate an image and is inexpensive in recording a plurality of images simultaneously. It is said.

  The first technical means includes a frame synchronization means for synchronizing a plurality of video signals and a plurality of synchronized video signals to be synthesized in a recording / reproducing apparatus that encodes the video signals and records and reproduces them on a recording medium. Synthesizing means for synthesizing the synthesized video signal into one synthesized video signal, encoding means for encoding the synthesized video signal synthesized into one, and formatting means for recording the synthesized video signal after formatting the recording medium. It is characterized by having.

  In the recording / reproducing apparatus according to the first technical means, the second technical means decodes the format of the recording medium and determines whether or not the encoded video signal read from the recording medium is a composite video signal. If the format decoding means, the decoding means for decoding the read encoded video signal, and the decoded video signal is a composite video signal composed of a plurality of video signals, any one of the composite video signals can be arbitrarily selected. Separating means for separating and outputting a designated video signal.

  According to a third technical means, in the recording / reproducing apparatus according to the first or second technical means, the image sizes of the synthesized video signal synthesized by the synthesizing means are a plurality of synchronized videos to be synthesized. It is characterized by having an image size larger than the total of the image sizes of the signal.

  According to a fourth technical means, in the recording / reproducing apparatus according to the third technical means, the image size of the video signal that is separated from the synthesized video signal by the separating means is synthesized by the synthesizing means. It is characterized by having the same image size as the image size.

  According to a fifth technical means, in the recording / reproducing apparatus according to the first to fourth technical means, MPEG2 is applied as a video signal encoding method in the encoding means.

  According to a sixth technical means, in the recording / reproducing apparatus according to the first to fifth technical means, the recording medium is an optical disk.

According to the present invention comprising the technical means as described above, it is possible to simultaneously record and reproduce a plurality of video signals on a recording medium in real time without requiring a complicated and expensive circuit configuration.
In addition, when combining multiple video signals into a single composite video signal or separating an arbitrary video signal from the composite video signal, there is no deterioration in image resolution due to compression or decompression, and good image quality The video signal can be recorded and played back.

  The recording / reproducing apparatus according to the present invention includes a recording / reproducing apparatus that uses an optical disc such as a CD (Compact Disk) or a DVD (Digital Versatile Disk) as a recording medium. A frame synchronizer that synchronizes the frame frequency of each video signal for recording as a signal is provided, and a plurality of synchronized video signals (each video signal is, for example, MPEG-2 MP @ ML (main profile / main level: 720 × 480 dots) image size (hereinafter abbreviated as MP @ ML), for example, MPEG2 MP @ H1440 (main profile high-1440 level: 1440 × 1080 dots; hereinafter abbreviated as MP @ H1440) or more One composite video of image size A recording circuit including a synthesis circuit, which is handled as a signal, and a separation circuit that separates a single reproduction synthesized video signal synthesized to an image size of MP @ H1440 or more into a plurality of video signals each having an MP @ ML image size. The recording / reproducing apparatus provided with the reproduction | regeneration system circuit provided with is characterized by the above-mentioned.

An embodiment of a recording / reproducing apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an example of the overall configuration of a recording / reproducing apparatus according to the present invention.
First, the frame frequency of the video signal is usually slightly different for each video source 101, 102,. Therefore, the recording / reproducing apparatus 10 according to the present invention includes a frame synchronizer 1 in order to synthesize a plurality of video signals input from the video sources 101, 102,.

Video signals from the sources 101, 102,... Are input to the frame synchronizer 1, and the frame frequency of each video signal is synchronized.
Here, if each input video signal is, for example, a video signal conforming to the NTSC system, and is an MP @ ML video of MPEG2, as described above, 720 pixels in the horizontal direction and 480 in the vertical direction. The image size is 720 × 480 pixels.

Next, each synchronized video signal is synthesized as one synthesized video signal in the synthesis circuit 2.
When two video signals of MP @ ML size are synchronized by the frame synchronizer 1 and input to the synthesis circuit 2, if the signals are NTSC signals, each video signal is 720 × as described above. The image size is 480 pixels. Here, in the synthesis circuit 2, it is possible to record a plurality of input video signals at the same time, and to combine the plurality of video signals into one synthesized video in a form that does not cause deterioration in image quality of each video signal. In order to synthesize the signal, a single image having a size larger than the total image size of all the input video signals without performing any compression processing on each of the plurality of input video signals. They are synthesized as two synthesized video signals.

  In the case of MPEG2 of a video signal conforming to the NTSC system, if it is MP @ H1440, the image size is 1440 × 1080 pixels, and if it is MP @ HL (main profile high level), the image size is 1920 × 1080 pixels. It is. Therefore, the synthesizing circuit 2 uses the MP @ H1440 size or MP @ HL size image size to synthesize a plurality of MP @ ML size video signals that are input in synchronization into a single synthesized video signal. I am going to do that. For this reason, the composition circuit 2 includes a frame buffer memory (image composition memory) having a size capable of handling a maximum image size of MP × HL.

  That is, for example, as shown in the schematic diagram of FIG. 2, the synthesis circuit 2 synthesizes the video signals A, B 111, 112 in the column direction when two video signals A, B 111, 112 are input. Then, it is output as one synthesized video signal 120 synthesized to an image size of 1440 × 1080 pixels. FIG. 2 is a schematic diagram showing an example of an image composition method in the recording / reproducing apparatus 10 according to the present invention. FIG. 2 (A) shows two MP @ ML sized images inputted in synchronization with each other. Signals A and B 111 and 112 are shown, and FIG. 2B shows a state in which the signals are combined into one composite video signal 120 of MP @ H1440 size. As described above, the image size of the synthesized video signal synthesized by the synthesis circuit 2 is larger than the sum of the image sizes of a plurality of synchronized video signals to be synthesized, for example, the video signals A, B 111, 112. It is made up of.

The synthesized video signal 120 synthesized into one signal is encoded by the MPEG encoder 3 and converted into an MPEG2 stream. After the converted MPEG2 stream is formatted in the format circuit 4 so as to indicate that the composite video signal 120 is recorded when the MPEG2 stream is recorded on the recording medium 5 of the recording / reproducing apparatus 10, for example, Recording is performed on a recording medium 5 made of an optical disk such as a DVD.
That is, at the time of formatting in the format circuit 4, as described above, information indicating that the video signal recorded on the recording medium 5 is a synthesized video signal is displayed in an information storage area (for example, a recording When a DVD is used as the medium 5, it is recorded in a DVD VOB (Video Object) information area or the like. In other words, the format circuit 4 provides means for formatting the recording medium 5 and recording the encoded video signal, that is, the synthesized video signal, together with information indicating that it is a synthesized video signal.

  In this way, the plurality of video signals recorded as one composite video signal on the recording medium 5 are naturally read out from the recording medium 5 as one video signal in the reproduction system circuit. The read video signal is decoded by the format decoding circuit 6 to obtain information that the video signal recorded on the recording medium 5 is a synthesized video signal obtained by synthesizing a plurality of video signals. That is, the format decoding circuit 6 decodes the format of the recording medium 5 and determines whether or not the encoded video signal read from the recording medium 5 is a composite video signal.

  Thereafter, the output of the format decoding circuit 6, that is, the encoded video signal read from the recording medium 5 is input to the MPEG decoder 7, and is synthesized into an image size of, for example, 1440 × 1080 pixels in the MPEG decoder 7. It is decoded as one composite video signal.

  When the decoded video signal is a composite video signal composed of a plurality of video signals as described above, one decoded composite video signal is input to the separation circuit 8 together with information indicating that it is a composite video signal. The Here, the frame buffer memory (image separation memory) of the separation circuit 8 for buffering the input composite video signal has a size capable of handling a maximum image size of MP × HL. If the recording system and the reproduction system do not operate simultaneously, it can be configured to be shared with the frame buffer memory of the synthesis circuit 2 in the recording system circuit.

  In the separation circuit 8, for example, as shown in the schematic diagram of FIG. 3, video signals A, B 111a and 112a synthesized in the column direction of one synthesized video signal 120a are arbitrarily designated as video signals. For example, when the video signal A 111a is separated and output to the video sink 200, only the 720 × 480 pixels of the video signal A 111a are separated from the decoded 1440 × 1080 pixel composite video signal 120a. Output. FIG. 3 is a schematic diagram showing an example of an image separation method in the recording / reproducing apparatus 10 according to the present invention. FIG. 3A is a diagram in which the video signals A, B 111a and 112a are combined into one. 3B shows one composite video signal 120a of the MP @ H1440 size, and FIG. 3B shows a state in which the arbitrarily specified video signal A 111a of MP @ ML size is separated from the composite video signal 120a. Yes. As described above, the image size of the video signal A 111a separated by the separation circuit 8 from the combined video signal 120a is the same as the image size of the video signal A 111 when combined in the combining circuit 2.

  As described above, by handling a plurality of MP @ ML-sized video signals as one composite video signal having an image size of MP @ H1440 or larger, image resolution is not deteriorated. Therefore, it is possible to provide an economical recording / reproducing apparatus that does not require an expensive special circuit. Here, for example, if an image size of MP @ H1440 is applied as a composite video signal, up to four video signals of MP @ ML size can be stored in the recording medium 5 without causing degradation in image resolution. It is possible to record and play back simultaneously.

It is a block block diagram which shows an example of the whole structure of the recording / reproducing apparatus which concerns on this invention. It is a schematic diagram which shows an example of the image synthesis method in the recording / reproducing apparatus which concerns on this invention. It is a schematic diagram which shows an example of the image separation method in the recording / reproducing apparatus which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Frame synchronizer, 2 ... Composition circuit, 3 ... MPEG encoder, 4 ... Format circuit, 5 ... Recording medium (optical disk), 6 ... Format decoding circuit, 7 ... MPEG decoder, 8 ... Separation circuit, 10 ... Recording / reproducing apparatus, 101, 102 ... Video source, 111, 111a ... Video signal A, 112, 112a ... Video signal B, 120, 120a ... Composite video signal, 200 ... Video sink.

Claims (6)

  In a recording / reproducing apparatus that encodes a video signal, records it on a recording medium, and reproduces it, frame synchronization means for synchronizing a plurality of video signals and a plurality of synchronized video signals to be combined into a single composite video signal And a combining means for combining, an encoding means for encoding the combined composite video signal combined into one, and a formatting means for recording the composite video signal encoded by formatting the recording medium. Recording / playback device.   2. The recording / reproducing apparatus according to claim 1, wherein the format decoding means decodes the format of the recording medium and determines whether or not the encoded video signal read from the recording medium is a composite video signal, and the read code When the decoded video signal is a composite video signal composed of a plurality of video signals, an arbitrarily designated video signal is separated from the composite video signal and output. A recording / reproducing apparatus.   3. The recording / reproducing apparatus according to claim 1, wherein the image size of the synthesized video signal synthesized by the synthesizing unit is larger than the total of the image sizes of the plurality of synchronized video signals to be synthesized. A recording / reproducing apparatus characterized by comprising a size.   4. The recording / reproducing apparatus according to claim 3, wherein the image size of the video signal separated from the synthesized video signal by the separating unit is the same as the image size of the video signal when synthesized by the synthesizing unit. And a recording / reproducing apparatus.   5. A recording / reproducing apparatus according to claim 1, wherein MPEG2 is applied as a video signal encoding method in said encoding means.   6. The recording / reproducing apparatus according to claim 1, wherein the recording medium is an optical disk.

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