JP2008048272A - Reproducing apparatus and reproducing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To acquire a good special reproduced picture even when there is partial dropout in data for special reproduction upon special reproduction, by interpolating the dropout. <P>SOLUTION: Data for special reproduction configured only by a low frequency component of an image signal which has been divided into a plurality of blocks and encoded for each block are read by an error correction code processing part 404 from a magnetic tape 403 in which the data are recorded. A dummy high frequency component for the data for special reproduction is generated by a data processing part for special reproduction 406 and decoded by adding the generated dummy high frequency component to the data for special reproduction. Even when there is partial dropout of the data for special reproduction, a reproduced picture smoothed so that the dropout part is not conspicuous is acquired. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a playback apparatus and a playback method, and more particularly to an interpolation processing technique related to a playback image.

  In a recording / reproducing apparatus that encodes a video signal and records it on a magnetic tape, when the MPEG method is adopted as the encoding method, the main image data and the special reproduction data encoded in the video signal are recorded in separate areas. The The main image data is data for normal reproduction, and the special reproduction data is data for high-speed reproduction for search reproduction and the like.

  Here, as an example, a case will be described in which a 1440 × 1080i video is encoded by the MPEG method and recorded on a magnetic tape. The number of effective pixels of the video signal to be encoded is 1440 samples in the horizontal direction and 1080 lines in the vertical direction for the luminance signal Y, and 720 samples in the horizontal direction and 540 lines in the vertical direction for the color difference signals Cb and Cr, respectively.

  As shown in FIG. 1, this is divided into 90 macroblocks (MB) in the horizontal direction and 68 in the vertical direction for encoding. The macro block of the luminance signal is composed of four DCT blocks, and each of the color difference signals Cb and Cr is composed of one DCT block.

  In addition, a DC component is extracted from a DCT block of an I picture composed of an intra frame in the encoded video signal to generate special reproduction data (see, for example, Patent Document 1). At this time, the extracted DC component data is converted into 6 bits for the luminance signal Y, and is converted into 5 bits for the color difference signals Cb and Cr. As a result, the special reproduction data is (6 × 4 + 5 × 2) = 34 bits per macroblock, and special reproduction data having a fixed length of (90 × 68 × 34) = 208080 bits per frame can be generated. It becomes.

  The special reproduction data is generated from the I picture. For example, as shown in FIG. 2, considering that 1 GOP (Group of Picture) is composed of N = 15 and M = 3, since the I picture is encoded every 15 frames, the special reproduction image is the main image. It is generated every 15 frames.

  In addition, special recording is performed during special playback, such as when the pre-recorded magnetic tape is edited and not all of the special playback data is recorded on the magnetic tape, or when an error occurs when reading from the magnetic tape. A case where the data for reproduction is not aligned for one frame is considered. In consideration of such a case, an information recording apparatus that can roughly display a special reproduction image even if the special reproduction data for one frame is not completely prepared has been proposed (for example, see Patent Document 2). .

  In the information recording apparatus described in Patent Document 2, the special reproduction data is divided into groups of the luminance signal Y0 and the color difference signals Cb, Cr and the luminance signals Y1, Y2, and Y3 in the macroblock, and each packet is formed into a fixed length and then independently The error correction encoding process is performed on the magnetic tape. As a result, even if special reproduction data is missing, the entire screen can be easily displayed roughly.

  In this manner, when the macro block is divided into groups of the luminance signal Y0 and the color difference signals Cb and Cr and the luminance signals Y1, Y2 and Y3, and each of them is packetized to a fixed length and recorded, FIG. Shown in FIG. 3A shows a state in which the packets of the luminance signal Y0 and the color difference signals Cb and Cr are lost, and FIG. 3B shows a state in which the packets of the luminance signals Y1, Y2, and Y3 are lost.

JP 2001-298706 A JP 2002-209179 A

  As described above, in the reproduced image obtained by reproducing the special reproduction data composed of the DC component extracted from the DCT block of the I picture, the pixel value of the 8 × 8 pixel region has the same level. Therefore, if special playback data is lost for some reason during special playback, the missing portion is compensated by using other special playback data such as other blocks in the same frame or the frame played immediately before. However, the missing part is easily noticeable in the specially reproduced image. An interpolation method capable of obtaining a more natural and smooth reproduced image is desired for lack of special reproduction data.

  An object of the present invention is to make it possible to obtain a good special reproduction image having no sense of incongruity by interpolating the missing portion even when special reproduction data is missing during special reproduction.

The reproduction apparatus of the present invention is a reproduction apparatus capable of reproducing encoded data composed only of low-frequency components of a video signal divided into a plurality of blocks and encoded for each block, wherein the encoded data is Reproducing means for reading the encoded data from the recorded recording medium, generating means for generating a pseudo high frequency component for the encoded data, and adding the pseudo high frequency component generated by the generating means to the encoded data And decoding means for decoding.
The reproduction apparatus of the present invention is a recording in which main image data of a video signal divided into a plurality of blocks and encoded, and special reproduction data composed only of low-frequency components of the encoded video signal are recorded. Reproducing means for reading out the main image data and the special reproduction data from the medium, detection means for detecting the loss of the special reproduction data read by the reproducing means, and generating the low frequency component and the pseudo high frequency component And interpolating means for interpolating the special reproduction data for which the loss is detected by the detecting means.
The reproduction method of the present invention is a reproduction method for reproducing encoded data composed of only low-frequency components of a video signal divided into a plurality of blocks and encoded for each block, wherein the encoded data is recorded. A reproduction step of reading the encoded data from the recorded recording medium, a generation step of generating a pseudo high frequency component for the encoded data, and a decoding by adding the pseudo high frequency component generated in the generation step to the encoded data And a decoding process.
The program of the present invention includes a reproduction step of reading encoded data from a recording medium in which encoded data composed only of a low frequency component of a video signal divided into a plurality of blocks and encoded for each block is recorded. And generating a pseudo high frequency component for the encoded data, and causing the computer to execute a decoding step of adding the generated pseudo high frequency component to the encoded data for decoding.
The computer-readable recording medium of the present invention is characterized in that the program is recorded.

  According to the present invention, even if special reproduction data is lost during special reproduction, a pseudo high frequency component is generated for the special reproduction data, and the special reproduction data that has been added is interpolated. As a result, it is possible to obtain a playback image that is smooth so that the missing portion is not conspicuous, and it is possible to obtain a good special playback image that does not give a sense of incongruity to the missing portion.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 4 is a block diagram showing a configuration example of a magnetic tape reproducing apparatus to which the reproducing apparatus according to an embodiment of the present invention is applied.

  In this embodiment, as a typical example, a video signal of 1440 × 1080i is encoded by the MPEG method, and the encoded main image data for normal reproduction and special reproduction data for high-speed reproduction are recorded on a magnetic tape. It is assumed that In the following description, in the magnetic tape reproducing apparatus for reproducing the magnetic tape on which the main image data and the special reproduction data are recorded, the case of performing the search reproduction which is mainly high-speed reproduction (special reproduction) will be described in detail. A detailed description of normal reproduction is omitted.

  The special reproduction data is generated by extracting a DC component, which is a low frequency component, from an 8 × 8 pixel DCT block in an I picture of a main image for normal reproduction as described above. Further, the special reproduction data is individually packetized after the luminance signal Y0 and the color difference signals Cb and Cr and the luminance signals Y1, Y2 and Y3 in the macro block are individually packetized, and then recorded. It shall be.

  In FIG. 4, a CPU 402 controls each functional unit constituting the magnetic tape reproducing device in the present embodiment based on a signal transmitted from the operation unit 401 by a user operation. The error correction code processing unit 404 reads data from the magnetic tape 403 under the control of the CPU 402, performs error correction processing on the read data, and outputs the data to the data separation unit 405. The data separation unit 405 selects special reproduction data or normal reproduction data (main image data) from the supplied reproduction data, and outputs the special reproduction data to the special reproduction data processing unit 406 for normal reproduction. The data is output to the decryption processing unit 408.

  The special reproduction data processing unit 406 converts the special reproduction data read from the magnetic tape 403 during special reproduction into DCT coefficients. In addition, the decoding processing unit 408 performs normal reproduction encoded main image data read from the magnetic tape 403 during normal reproduction, and special reproduction data converted into DCT coefficients by the special reproduction data processing unit 406. Perform decryption. The video signal processing unit 409 displays the reproduced image obtained by the decoding processing unit 408 on the display unit 410 and outputs it to an external device via the D / A (digital-analog) conversion unit 411.

  When an instruction for normal reproduction is given from the operation unit 401, the CPU 402 controls the error correction code processing unit 404 to reproduce data from the magnetic tape 403. The error correction code processing unit 404 performs error correction processing on the reproduced data, and then outputs it to the data separation unit 405.

  The data separation unit 405 selects normal reproduction data (main image data) from the reproduction data and outputs it to the decoding processing unit 408. The decoding processing unit 408 decodes the normal reproduction data and outputs it to the video signal processing unit 409. The video signal processing unit 409 displays the decoded video signal on the display unit 410, converts it into an analog video signal via the D / A conversion unit 411, and outputs it to an external device.

  When an instruction for search reproduction is given from the operation unit 401, the CPU 402 controls the error correction code processing unit 404 to convey the magnetic tape 403 at a predetermined speed higher than that during normal reproduction, while moving the magnetic tape 403. Play the playback data from. The reproduction data read from the magnetic tape 403 is subjected to error correction processing by the error correction code processing unit 404, and only the reproduction data obtained normally is supplied to the data separation unit 405.

  The data separation unit 405 separates only the special reproduction data from the input reproduction data, adds update information indicating that the data has been normally updated, and supplies the data to the special reproduction data processing unit 406. . The special reproduction data supplied from the data separation unit 405 is stored in the RAM 407 by the special reproduction data processing unit 406, and the special reproduction data acquired sequentially is stored in the RAM 407.

  The special reproduction data processing unit 406 converts the special reproduction data into DCT coefficients when the special reproduction data for one frame is acquired. Since the special reproduction data is composed of the DC component of the DCT coefficient, the special reproduction data processing unit 406 converts each special reproduction data into a DC component as shown in FIG. Conversion to DCT coefficients is performed by inserting “0”. In FIG. 5, only the luminance signal Y is shown, but the same applies to the color difference signals Cb and Cr.

  Here, the special reproduction data stored in the RAM 407 is used for special reproduction for one frame of a special reproduction image when an error in reading from the magnetic tape 403 occurs or when the special reproduction data is connected and recorded on the magnetic tape 403. There may be cases where the data is not complete. The special reproduction data processing unit 406 has a function of interpolating the missing portion when the special reproduction data is missing. The special reproduction data processing unit 406 includes a data loss detection unit 421, an interpolation value generation unit 422, and a conversion processing unit 423.

  The data loss detection unit 421 determines whether the special reproduction data stored in the RAM 407 is a special reproduction data packet written previously or a newly written special reproduction data packet. Then, the loss of special reproduction data is detected. This determination is made based on the update information added to the special reproduction data by the data separation unit 405.

  Based on the detection result of the data loss detection unit 421, the interpolation value generation unit 422 generates an interpolation value from the neighboring pixel values (specifically, the data values of neighboring DCT blocks) of the special reproduction data missing due to an error or the like. To do. The interpolation value is composed of a DC component corresponding to the special reproduction data and an AC component which is a high frequency component, which is a low frequency component. The conversion processing unit 423 converts the special reproduction data into DCT coefficients. Also, the conversion processing unit 423 can replace the interpolation value generated by the interpolation value generation unit 422 with a DCT coefficient.

Here, among the DCT coefficients shown in FIG. 5, the larger the U value, the higher the horizontal frequency, and the larger the V value, the higher the vertical frequency.
For example, as shown in FIG. 6A, by weighting the AC component located at (U, V) = (1, 0), the reproduced image after iDCT (inverse DCT) is simulated in the horizontal direction. It is possible to generate gradation. That is, by weighting the AC component located at (U, V) = (1, 0), it is possible to generate a reproduced image in which gradation values change sequentially in the horizontal direction.

  In addition, as shown in FIG. 6B, by weighting the AC component located at (U, V) = (0, 1), a pseudo gradation is generated in the vertical direction in the reproduced image after iDCT. It is possible to make it. That is, by weighting the AC component located at (U, V) = (0, 1), it is possible to generate a reproduced image in which tone values change in order with respect to the vertical method.

Further, as shown in FIG. 7, reproduction after iDCT is performed by weighting the AC components located at both (U, V) = (1, 0) and (U, V) = (0, 1). It is also possible to generate pseudo gradations in the horizontal and vertical directions in the image.
As shown in FIGS. 6A, 6B, and 7, it is possible to adjust the shade of the pseudo gradation generated by manipulating the absolute value of the AC component. The direction in which the gradation change is generated can be controlled by operating.

  Thus, the interpolation value generation unit 422 becomes the low frequency AC component in addition to the missing special reproduction data (DC component) (U, V) = (1, 0), (U, V) = ( For 0, 1), a DC component and a pseudo AC component are generated from data of DCT blocks adjacent to the missing data. The conversion processing unit 423 realizes interpolation processing of missing special reproduction data by weighting these AC components during DCT coefficient conversion.

  In the following, as shown in FIG. 8, the luminance signals Y1, Y2, and Y3 are missing, and the special reproduction data composed only of the luminance signal Y0 and the color difference signals Cb, Cr is compared with the luminance signals Y1, Y2, and Y3. A description will be given by taking the case of interpolating each as an example.

<Interpolation of luminance signal Y1>
With reference to FIG. 9A, interpolation of the luminance signal Y1 will be described.
In FIG. 9 (a), the special reproduction data corresponding to the DCT block represented by diagonal lines indicates the missing luminance signal Y1 to be interpolated, and Y0 [0] to Y0 [3] are luminances used for the interpolation processing. The signal Y0 is shown.

  As shown in the above equation (1), the DC component of (T, V) = (0, 0) among the DCT coefficients is the luminance signal Y0 [0] located on the left and right of the missing luminance signal Y1 and the luminance. It is generated from the average value of the signal Y0 [1]. The AC component with (U, V) = (1, 0) is generated by multiplying the value obtained by subtracting the luminance signal Y0 [1] from the luminance signal Y0 [0] by the coefficient k. Here, an arbitrary value can be set for the coefficient k, and in this embodiment, it is assumed that k = 0.2 is set as an example. The AC component with (U, V) = (0, 1) is set to “0” because the value of the luminance signal Y0 located on the left and right of the missing luminance signal Y1 exists.

<Interpolation of luminance signal Y2>
Next, the interpolation of the luminance signal Y2 will be described with reference to FIG.
In FIG. 9 (b), the special reproduction data corresponding to the DCT block represented by hatching indicates the missing luminance signal Y2 to be interpolated, and Y0 [0] to Y0 [3] are luminance signals used for interpolation. Y0 is shown.

  As shown in the expression (2), the DC component of (U, V) = (0, 0) among the DCT coefficients is the luminance signal Y0 [0] positioned above and below the missing luminance signal Y2 and the luminance. It is generated from the average value of the signal Y0 [2]. Further, the AC component of (U, V) = (1, 0) is set to “0” because the value of the luminance signal Y0 located above and below the missing luminance signal Y2 exists. The AC component with (U, V) = (0, 1) is generated by multiplying the value obtained by subtracting the luminance signal Y0 [2] from the luminance signal Y0 [0] by the coefficient k.

<Interpolation of luminance signal Y2>
Next, the interpolation of the luminance signal Y3 will be described with reference to FIG.
In FIG. 9 (c), the special reproduction data corresponding to the DCT block represented by diagonal lines shows the missing luminance signal Y3 to be interpolated, and Y0 [0] to Y0 [3] are luminance signals used for interpolation. Y0 is shown.

  As shown in the equation (3), the DC component with (U, V) = (0, 0) among the DCT coefficients has a missing luminance signal Y3 from the luminance signals Y0 [0] to Y0 [3]. Since they are located at the same distance, they are generated from the average value of the luminance signals Y0 [0] to Y0 [3]. Further, the AC component of (U, V) = (1, 0) is calculated based on the average value of the luminance signal Y0 [0] and the luminance signal Y0 [2], and the luminance signal Y0 [1] and luminance signal Y0 [3]. It is generated by multiplying the value obtained by subtracting the average value of the coefficient k. The AC component where (U, V) = (0, 1) is the average of the luminance signal Y0 [2] and the luminance signal Y0 [3] from the average value of the luminance signal Y0 [0] and the luminance signal Y0 [1]. It is generated by multiplying the value obtained by subtracting the value by a coefficient k.

  As described above, for example, as shown in FIG. 10, by performing interpolation processing on the special reproduction data lacking the luminance signals Y1, Y2, and Y3, a reproduced image obtained by smoothly interpolating the missing portion is obtained. Is possible.

In FIGS. 9A to 9C, the case where the luminance signals Y1, Y2, and Y3 are missing and the interpolation is performed using the luminance signal Y0 has been described. However, even when the luminance signal Y0 is missing. Interpolation processing can be realized by basically the same method.
FIG. 9D is a diagram for explaining interpolation of the luminance signal Y0. In FIG. 9 (d), the special reproduction data corresponding to the DCT block represented by diagonal lines indicates the missing luminance signal Y0 to be interpolated, and Y1 [0], Y1 [1] and Y2 [0], Y2 [1] indicates the luminance signal Y used for the interpolation processing.

As shown in the equation (4), the DC component of (T, V) = (0, 0) among the DCT coefficients is the luminance signal Y1 [0] positioned above, below, left and right of the missing luminance signal Y0. It is generated from the average value of the luminance signal Y1 [1], the luminance signal Y2 [0], and the luminance signal Y2 [1]. The AC component with (U, V) = (1, 0) is obtained by subtracting the coefficient k from a value obtained by subtracting the luminance signal Y1 [1] from the luminance signal Y1 [0] located on the left and right of the missing luminance signal Y0. Generated by multiplication. For the AC component where (U, V) = (0, 1), the value obtained by subtracting the luminance signal Y2 [1] from the luminance signal Y2 [0] positioned above and below the missing luminance signal Y0 is multiplied by the coefficient k. Generated.
The same method can be applied to the case where the color difference signals Cb and Cr are lost, but the description thereof is omitted here.

  The special reproduction data converted into the DCT coefficient by the special reproduction data processing unit 406 in this way is supplied to the decoding processing unit 408, and the decoding processing unit 408 performs decoding by the iDCT processing, thereby reproducing the reproduced video. The signal is supplied to the video signal processing unit 409 as a signal. The video signal processing unit 409 supplies the input special reproduction image to the D / A conversion unit 411. The special reproduction image supplied to the D / A conversion unit 411 is converted into an analog video signal by the D / A conversion unit 411 and then output as a video signal. At the same time, the image size is converted in accordance with the display size of the display unit 410, output to the display unit 410, and the special reproduction image is displayed on the display unit 411.

  As described above, according to the present embodiment, the special reproduction data (DC component) of the missing part is generated using the data value (neighboring pixel value) of the neighboring block of the missing special reproduction data. The high frequency component (pseudo AC component) is generated and weighted. As a result, the 8 × 8 pixel area of the special reproduction image related to the missing special reproduction data has a data value corresponding to the adjacent DCT block, and the data value is set in the area according to the adjacent DCT block. It is possible to generate and interpolate a reproduced image that is changed smoothly. Therefore, when special reproduction data is missing, the missing portion is less noticeable, and a more natural and smooth special reproduction image with no sense of incongruity can be obtained.

In the above description, the interpolation processing when special reproduction data is lost for some reason has been described. However, pseudo AC components are added to all special reproduction data including those that are not lost. Is possible.
FIG. 11 is a diagram for explaining a method of adding a pseudo high frequency component to special reproduction data. In FIG. 11, the special reproduction data corresponding to the DCT block indicated by hatching indicates the luminance signal Yn to which the AC component is added, and Y [0] to Y [3] are the luminances used for generating the AC component. Signal Y is shown.

  As shown in the equation (5), the AC component of (T, V) = (1, 0) among the DCT coefficients is the luminance signal Y [ 2] can be generated by multiplying the value obtained by subtracting the luminance signal Y [3] from the coefficient k. Further, the AC component of (U, V) = (0, 1) is a value obtained by subtracting the luminance signal Y [1] from the luminance signal Y [0] positioned above and below the luminance signal Yn to be AC component added. Can be generated by multiplying by a coefficient k. For the DC component where (U, V) = (0, 0), the special reproduction data of the luminance signal Yn to be added with the AC component is used. If the special reproduction data of the luminance signal Yn is lost, the special reproduction data (DC component) may be generated using the data value (neighboring pixel value) of the neighboring block as described above.

  As described above, a pseudo gradation can be generated for the entire special reproduction image obtained based on the special reproduction data, and a special reproduction image in which the boundary of the DCT block is smoothed can be obtained. Become.

(Other embodiments of the present invention)
In order to operate various devices to realize the functions of the above-described embodiments, to realize the functions of the above-described embodiments with respect to an apparatus or a computer (CPU or MPU) in the system connected to the various devices. Supply software programs. And what was implemented by operating the said various devices according to the program stored in the computer of the system or the apparatus is also contained under the category of this invention.
In this case, the software program itself realizes the functions of the above-described embodiments, and the program itself constitutes the present invention. Further, means for supplying the program to the computer, for example, a recording medium storing the program constitutes the present invention. As a recording medium for storing such a program, for example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.
Further, when the supplied program realizes the functions of the above-described embodiment in cooperation with an operating system or other application software running on the computer, the program is also included in the embodiment of the present invention. Needless to say.
Further, after the supplied program is stored in a memory provided in a function expansion board or a function expansion unit related to the computer, a CPU or the like provided in the function expansion board or the like based on an instruction of the program may be part of the actual processing Do everything. Needless to say, the present invention includes the case where the functions of the above-described embodiments are realized by the processing.

  The above-described embodiments are merely examples of implementation in carrying out the present invention, and the technical scope of the present invention should not be construed as being limited thereto. That is, the present invention can be implemented in various forms without departing from the technical idea or the main features thereof.

It is a figure which shows the relationship of the image resolution of a main image and a special reproduction image. It is a figure for demonstrating the space | interval which a special reproduction | regeneration image is produced | generated. It is a figure which shows a mode that the data for special reproduction were missing per packet. It is a block diagram which shows the structural example of the reproducing | regenerating apparatus in embodiment of this invention. It is a figure which shows the relationship between the data for special reproduction | regeneration, and a DCT coefficient. It is a figure which shows the reproduction | regeneration image after a DCT coefficient and an inverse DCT process. It is a figure which shows the reproduction | regeneration image after a DCT coefficient and an inverse DCT process. It is a figure which shows the data for special reproduction | requirements from which the luminance signals Y1, Y2, and Y3 were missing. It is a figure for demonstrating the interpolation method of the luminance signal in the data for special reproduction | regeneration. It is a figure which shows an example of the special reproduction | regeneration image obtained from the data for special reproduction | regeneration after an interpolation process. It is a figure for demonstrating the addition method of the pseudo high frequency component with respect to the data for special reproduction | regeneration.

Explanation of symbols

402 CPU
403 Magnetic tape 404 Error correction code processing unit 405 Data separation unit 406 Special reproduction data processing unit 408 Decoding processing unit 409 Video signal processing unit 421 Data missing detection unit 422 Interpolation value generation unit 423 Conversion processing unit

Claims (13)

A reproduction device capable of reproducing encoded data composed of only low frequency components of a video signal divided into a plurality of blocks and encoded for each block,
Reproducing means for reading the encoded data from a recording medium on which the encoded data is recorded;
Generating means for generating a pseudo high frequency component for the encoded data;
A reproduction apparatus comprising: decoding means for adding the pseudo high-frequency component generated by the generation means to the encoded data and decoding the encoded data.   2. The reproducing apparatus according to claim 1, wherein the generation unit generates the pseudo high frequency component using data of a block adjacent to the block to which the pseudo high frequency component is added.   3. The decoding unit according to claim 1, wherein when the encoded data read by the reproducing unit is missing, the decoding unit adds the pseudo high frequency component to the encoded data for decoding. Playback device. When there is a lack in the encoded data read by the reproduction means,
The generating means generates the low frequency component and the pseudo high frequency component using data of neighboring blocks of the block in which the encoded data is missing,
2. The reproducing apparatus according to claim 1, wherein the decoding unit adds the pseudo high frequency component to the low frequency component generated by the generating unit in place of the encoded data of the missing block and decodes the decoded data. .   The reproduction apparatus according to claim 1, wherein the encoded data is special reproduction data.   6. The reproduction apparatus according to claim 5, wherein the special reproduction data is composed of a plurality of blocks including first data and second data.   2. The pseudo high-frequency component includes a first component that generates a gradation change in a horizontal direction and a second component that generates a gradation change in a vertical direction within the block. The reproduction apparatus according to any one of? 6. The main image data of the video signal divided into a plurality of blocks and encoded, and the main image data from the recording medium on which the special reproduction data composed only of the low frequency component of the encoded video signal is recorded Reproducing means for reading out the special reproduction data;
Detecting means for detecting missing special reproduction data read by the reproducing means;
A reproduction apparatus comprising: an interpolation processing unit that generates the low-frequency component and the pseudo-high-frequency component and interpolates special reproduction data in which a loss is detected by the detection unit.   The said interpolation process means produces | generates the said low frequency component and pseudo | simulation high frequency component of the block from which the loss of the data for special reproduction | regeneration was detected using the data of the block adjacent to the said block. The reproducing apparatus as described.   The special reproduction data is stored after being subjected to error correction coding processing, and the detection means includes error correction means for performing error correction processing on the special reproduction data read by the reproduction means, and the special reproduction data 10. The reproducing apparatus according to claim 8, wherein an error that cannot be corrected in the reproduction data is detected as a loss of the special reproduction data. A reproduction method for reproducing encoded data composed of only low frequency components of a video signal divided into a plurality of blocks and encoded for each block,
A reproduction step of reading the encoded data from the recording medium on which the encoded data is recorded;
Generating step for generating a pseudo high-frequency component for the encoded data;
And a decoding step of decoding by adding the pseudo high frequency component generated in the generation step to the encoded data. A reproduction step of reading the encoded data from the recording medium in which the encoded data composed only of the low frequency components of the video signal divided into a plurality of blocks and encoded for each block is recorded;
Generating a pseudo high frequency component for the encoded data;
A program for causing a computer to execute a decoding step of adding the generated pseudo-high frequency component to the encoded data and decoding the encoded data.   13. A computer-readable recording medium on which the program according to claim 12 is recorded.

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