KR100698185B1 - Apparatus and Method for recording / regeneration - Google Patents

Abstract

The present invention relates to a recording and reproducing apparatus capable of reproducing from an image at the time of recording and a recording and reproducing method.

The present invention provides a recording and reproducing apparatus including a system decoder for detecting a bit string from a received broadcast signal and storing the bit string in a first memory unit, and for reproducing the stored bit string to the first memory unit. A processor unit in which a first flag at the start of recording of a broadcast signal is captured as a still picture, a second memory unit in which a still image captured by the processor unit is stored, and a video decoding unit in which a bit string stored in the first memory unit is decoded And a screen output unit for outputting a bit string of the broadcast signal decoded by the video decoding unit together with the still image stored in the second memory unit, and a controller for controlling the processor as a whole. to provide.

Therefore, for the channel efficiency, a randomly accessible video may have a long period. In this case, an image closer to the original image may be restored from a bit stream starting at the time of recording, instead of the randomly accessible video.

Broadcast recording, PVR

Description

Recording and playback device and recording and playback method {Apparatus and Method for recording / regeneration}

1 is a block diagram of a recording / playback apparatus according to the present invention

2 is a flowchart of a recording method according to the present invention;

3 is a flowchart of a reproducing method according to the present invention.

* Explanation of symbols for main parts of drawings *

10: receiver 20: system decoder

30: video decoding unit 40: memory unit

50: auxiliary memory unit 60: control unit

70: screen output unit 80: processor unit

The present invention relates to an image reproducing apparatus, and more particularly, to a recording / reproducing apparatus and a recording and reproducing method.

Broadcast recording of analog television immediately records the received signal in analog. Therefore, there is a signal deterioration, but playback is possible immediately from the time of recording. However, in the case of broadcasting of digital television, it is difficult to reproduce the video directly from the time of recording by using a method of compressing and transmitting an image.

As a method of storing a broadcast, there is a method of storing an incoming bit stream as it is, and receiving and interpreting the stored stream as a signal of a form transmitted from a broadcasting station. In this method, since an image can be obtained from a random access point in the transmitted bit stream, a bit stream entered before the random access video cannot be decoded. Random access refers to an approach that takes the same access time when reading or writing data to or from a storage device, ie, without having to sequentially access the data stored in the storage device. Tell them how you can find and access them. This will mean a time point at which the stored bit string can be decoded.

In the process of watching a broadcast, a bit string may come in such as P (0), P (1), P (2), P (3), I (4), P (5), P (6) ... In this case, it is possible to decode from the I (4) at which the bit string starts, and even if the four P-pictures of the previous part are stored by the conventional recording method, they cannot be decoded because there is no reference image. Therefore, even if recording is started from P (0), P (0) to P (3) cannot be decoded and cannot be played back. Therefore, decoding is possible from the time when I (4) enters, and the image shown on the screen can also be seen from I (4).

However, if you start recording from P (0) as above while watching the broadcast, you are currently watching the broadcast, and since there is already a video to refer to before, P (0) to P ( It also provides images up to 3). However, if this bit string is to be stored and reproduced, there is no information about the previous reference image, so that the images from P (0) to P (3) cannot be restored.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention relates to a recording method capable of decoding and reproducing stored video before a point in time that can be randomly accessed, and a reproduction method thereof.

In order to achieve the above object, a recording and reproducing apparatus for detecting a bit string from a received broadcasting signal and storing the bit string in a first memory unit, wherein the first flag at the start of recording among the received broadcasting signals corresponds to a still image corresponding thereto. A processor unit for capturing a video, a second memory unit for storing a still image captured by the processor unit, a video decoder for decoding a bit string stored in the first memory unit, and a still image stored in the second memory unit. It provides a recording / playback apparatus comprising a screen output unit for displaying a broadcast signal decoded by the bit stream in the video decoding unit, and a control unit for controlling the components as a whole.

The processor unit provides a recording / reproducing apparatus, wherein the first flag is captured as a still image and then compressed.

And a system decoder which reads the bit string stored in the second memory unit into the first memory unit during reproduction.

A method of recording a broadcast signal by detecting a bit stream from a received broadcast signal and storing the bit stream in a memory unit, the method comprising: capturing a first flag of the bit stream of the received broadcast signal as a still image; A method of recording a signal comprising compressing an image and storing the compressed still image.

The first flag of the bit string detected in the received broadcast signal is one, and the flag coming after the first is zero.

A first flag of a bit string detected in the received broadcast signal is zero, and a flag coming after the first is one.

The storing of the compressed still image provides a method of recording a signal, wherein the compressed still image is stored separately from the bit string detected from the broadcast signal.

Restoring a still image corresponding to the first flag captured and stored separately from among the bit strings detected in the received broadcast signal, decoding the bit string after the first flag using the flag of the restored still image; And displaying the decoded image in succession with the reconstructed still image.

The decoding of the bit stream after the first flag using the flag of the reconstructed still image comprises decoding a second flag due to the still image corresponding to the reconstructed first flag. Provide a way to play.

The decoding of the bit stream after the first flag by using the flag of the reconstructed still image comprises: decoding the bit stream until the last bit string is reached in series with reference to the second flag. It provides a method for reproducing a signal.

The displaying may provide a method of reproducing a recorded signal, characterized in that the bit stream is sequentially decoded and output on the screen by using the reconstructed still image corresponding to the first flag as a start point of reproduction.

Therefore, according to the present invention, there may be a case in which a randomly accessible video has a long period for channel efficiency. In this case, an image close to the original video can be restored from the bit stream starting at the time of recording, instead of the randomly accessible video. have.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention that can specifically realize the above object will be described.

1 is a block diagram of a recording / reproducing apparatus according to the present invention.

Referring to FIG. 1, a receiver 10 for receiving a broadcast signal, a system decoder 20 for detecting and storing a bit string from the received broadcast signal, a memory 40 for storing the bit string, and stored bits The video decoding unit 30 which decodes the column, the screen output unit 50 which outputs the decoded bit string, and the processor unit 80 and the second memory unit 50 are included.

The receiver 10 receives detection and broadcast.

The system decoder 20 stores the bit string received and detected by the receiver in the memory 40. At the time of reproduction, the bit string stored in the second memory is read into the memory. Bit sequence means a shape in which bits are connected in order to represent special information. Bit means a base of two sets of two events that are mutually exclusive as units of information measure. It means the amount of selection information expressed in logarithm. The bit strings may come in as P (0), P (1), P (2), P (3), I (4), P (5), P (6). According to the conventional recording / reproducing apparatus, the P (0), P (1), P (2), and P (3) flags of the detected bit strings cannot be decoded because they cannot be decoded because there is no reference image, and thus random access is not possible. Playback is possible from the possible I (4) video. To solve this problem, a processor unit for storing the first P (0) flag among four P flags and a second memory unit for storing four P images are proposed.

The video decoding unit 30 decodes the bit stream stored in the memory and has input / output with a predetermined partial memory. It has parameters for decoding and memory I / O necessary for video decoding.

The first memory unit 40 temporarily stores contents necessary for video decoding and data for long-term storage. In the drawing, the memory unit is shown to correspond to the second memory unit 50 shown as the auxiliary memory unit.

The processor 80 captures and stores the first flag P (0) as a still image instead of a bit string in the received broadcast signal. Therefore, when the P (0) flag is stored as a bit string, the P (0) flag can not be played because there is no image to refer to, and the first image can be provided by capturing and storing the image as a direct image. The captured still image corresponding to the P (0) flag is stored in the second memory unit 50. At this time, the first flag can be captured as a still image and then compressed and stored. At the time of reproduction, the compressed bit string is decoded and stored in the memory in a format that can be output to the screen. In the drawing, the coprocessor is referred to as a processor separate from the overall processor.

The second memory unit 50 stores a bit stream in order to perform a function according to the present invention, and transfers data necessary for a reproduction function to the memory unit. Still images are also captured and stored in a compressed form. In the drawing, the auxiliary memory unit 50 is shown to mean separate from the main memory unit.

The screen output unit 70 displays a captured screen of a still image while a video is output.

The controller 80 is responsible for the overall control of the processor.

The overall operation will be described by way of example.

It is assumed that the bit stream stored through the recording function is an MPEC-2 bit stream, and that the compressed bit stream is a video bit stream conforming to the base profile of H.264, and that the first processor compresses the first image in JPEG format. do. Assumed here is only an embodiment, and this patent is not limited by the compression algorithm. In the general form of reception, the MPEG2-TS stream is received by the receiver and the system decoder stores the stream in memory. The H.264 decoder decodes it and sends it to the screen output unit. The image going to the screen output unit is the restored image.

In the case of recording while watching a broadcast, the control unit causes the system decoder to store the MPEG2-TS stream in the memory while simultaneously storing the stream in the second memory. If the start point of recording is the P picture, the second memory stores data related to the P picture. However, even if the video decoder uses the previous video to decode the P video, the video decoder may output a normal video to the screen output unit. The normal image at the start of recording, that is, the data stored for reading from the screen output unit and being transferred to the display device, is stored in the second memory after compression using a compression algorithm of the still image.

When the recorded broadcast is reproduced, the compressed still image stored in the second memory unit 50 is output, and the first and subsequent flags are decoded using this, and are continuously output to the screen output unit 70.

2 is a flowchart illustrating a method of recording a signal according to the present invention.

Referring to FIG. 2, when recording is started, the first flag at the start of recording is set to one (1) (s21). This is to distinguish the first flag from later ones by setting the first flag to one (1) and then leaving the flag zero (0). So vice versa. That is, the first flag may be set to zero and the subsequent flag may be set to one. The following description continues the case where the first flag is set to work. The bit string detected by the receiver is decoded (s22) and stored in the memory unit (s23). At this time, it is determined whether the bit string is terminated (s24), and if the bit string is terminated, the entire recording process ends. However, if the bit string does not end, the video recording process continues. If the bit string has not ended, it is determined whether the first flag is work (S25). In this case, if the flag corresponds to day, since the flag is the first flag at the start of recording, it is captured and made into a still image (s26). The captured still image is compressed (s27) and additionally stored in the second memory unit 50. The flag after the first flag is set to zero to distinguish it from the first flag (s29). After the flag is set to zero, the process returns to the decoding step of the broadcast bit stream (s22) and the process is repeated.

The overall operation will be described by way of example.

It is assumed that the bit stream stored through the recording function is an MPEC-2 bit stream, and that the compressed bit stream is a video bit stream conforming to the base profile of H.264, and that the first processor compresses the first image in JPEG format. do. Assumed here is only an embodiment, and this patent is not limited by the compression algorithm. In the general form of reception, the MPEG2-TS stream is received by the receiver and the system decoder stores the stream in memory. The H.264 decoder decodes it and sends it to the screen output unit. The image going to the screen output unit is the restored image.

When recording while watching a broadcast, the MPEG2-TS stream is stored in the memory while the stream is also stored in the second memory. If the start point of recording is the P picture, the second memory stores data related to the P picture. Therefore, even if the first flag is a P image, it is separately stored as a still image, thereby providing a base image at the start of decoding.

3 shows a flowchart of a method of reproducing a signal according to the present invention.

Referring to FIG. 3, when playback starts, the still image information stored in the second memory unit is loaded (s31). After the still image information is loaded, the image is restored (s32). The first flag at the start of recording is stored as a still image and then restored, and the subsequent flag is stored as a bit string and then subjected to a storage bit string decoding step during playback (s33). An image is output based on the reconstructed still image, and on the basis of this, an image of a subsequent flag is also output to the screen in series. After that, it is determined whether or not the bit string is over (s35). If the bit string is over, the playback process is terminated. In this case, if the bit string is not finished, the process returns to the storage bit string decoding step s33 and repeats the above process.

The overall operation will be described by way of example.

It is assumed that the bit stream stored through the recording function is an MPEC-2 bit stream, and that the compressed bit stream is a video bit stream conforming to the base profile of H.264, and that the first processor compresses the first image in JPEG format. do. Assumed here is only an embodiment, and this patent is not limited by the compression algorithm. In the general form of reception, the MPEG2-TS stream is received by the receiver and the system decoder stores the stream in memory. The H.264 decoder decodes it and sends it to the screen output unit. The image going to the screen output unit is the restored image.

When compression is performed according to the method given in the above example, it can be decoded as follows. First, the type of the first image is determined by reading the MPEG2-TS bit stream stored in the second memory. If the random access is guaranteed I video, the TS bit stream can be decoded as it is and displayed on the screen. If the random access is not guaranteed, the first image is stored using the still image data stored by the coprocessor. Restore the still image. The still image is taken as a reference image, and the second image is reconstructed by the algorithm of H.264.

In this case, the second image may be normally restored, but there may be a case in which the image referred to in the second image does not exist. In this case, decoding is forcibly referred to the first, i.e., the reconstructed image. By subsequently decoding the subsequent bit stream by referring to the image restored to the still image, playback can be performed from the start of recording.

The present invention is not limited to the above-described embodiments, and as can be seen in the appended claims, modifications can be made by those skilled in the art to which the present invention belongs, and such modifications are within the scope of the present invention.

The effects of the recording / reproducing apparatus and the recording and reproducing method according to the present invention described above are as follows.

For the channel efficiency, a randomly accessible video may be longer in this case. In this case, an image close to the original video may be restored from a bit stream starting at the time of recording, rather than the randomly accessible video.

Claims (11)

A recording and reproducing apparatus for detecting a bit string from a received broadcast signal and storing the bit string in a first memory unit. A processor unit for capturing a first flag at the start of recording among the received broadcast signals as a still image corresponding thereto; A second memory unit which stores a still image captured by the processor unit; A video decoding unit to decode a bit string stored in the first memory unit; A screen output unit displaying a broadcast signal from which a bit string is decoded in the video decoding unit together with a still image stored in the second memory unit; A controller which controls the component as a whole; Recording / playback device comprising a. The method of claim 1, And the processor unit compresses the first flag after the first flag is captured as a still image. The method of claim 1, And a system decoding unit for reading the bit string stored in the second memory unit into the first memory unit at the time of reproduction. A method of recording a broadcast signal by detecting a bit string in a received broadcast signal and storing the bit string in a memory unit, the method comprising: Capturing a first flag of the bit string of the received broadcast signal as a still image; Storing the captured still image; And And storing the bit string after the first flag stored as the still image. The method of claim 4, wherein The captured still image is compressed and stored, the method of recording a signal. The method of claim 4, wherein And distinguishing a first flag and a subsequent flag by differentiating a value of a first flag of a bit string detected from the received broadcast signal from a value of a first incoming flag. The method of claim 4, wherein The storing of the still image may include storing the still image separately from the bit string detected from the broadcast signal. A method of reproducing a recorded signal by restoring a bit string detected and stored in a received broadcast signal, the method comprising: A first flag of the bit strings detected in the received broadcast signal is separately captured and stored as a still image, and restoring a still image corresponding to the stored first flag; Sequentially decoding the bit stream using the restored bit stream after the stored first flag as the first reference picture; Displaying the decoded image consecutively with the reconstructed still image. The method of claim 8, The decoding of the bit stream after the first flag comprises: decoding a second flag using a still picture corresponding to the restored first flag as a reference picture. The method of claim 9, Decoding the bit stream after the first flag may decode the next bit string with reference to the decoded second flag and refer to the bit string that precedes the sequence of bits until the last bit string is reached. A method of reproducing a recorded signal, characterized by decoding a column. The method of claim 8, The displaying may include outputting a serially decoded bit string to a screen using a restored still image corresponding to a first flag as a starting point of reproduction.

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