JP2010258983A - Reproducing device, and reproduction processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a reproducing device and a reproduction processing method capable of preventing the device from giving a visually poor impression to audience, in accordance with a frame rate in the reproducing device. <P>SOLUTION: Video data are data produced from picture data shown continuously during a plurality of frames. The reproducing device 100 to decode and reproduce encoded video data is equipped with: a priority-order granting unit 4 to grant a priority order to the picture data included in the video data, in the order of encoded first picture data, and second picture data encoded in reference to the picture data in other frames; a picture selector 5 to select the picture data of the predetermined number of frame in the descending priority order; and a decoder 6 to decode the picture data selected from the picture selector 5. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a playback apparatus and a playback processing method.

Currently, in transmission / reception of video data in which a plurality of frames of picture data are continuous, MPEG or H.264 is used. Video data is encoded by an encoding method such as the H.264 / AVC method. Thereby, the communication load is reduced.
When playing back encoded video data, the frame rate of the playback device may be lower than the frame rate at which the video data is transmitted. In that case, one of the consecutive picture data included in the video data is skipped and the decoding process is performed.

However, if any picture data is skipped, the display interval of the picture data decoded without being skipped is disturbed. Therefore, it gives a visual impression to the viewer.
Therefore, Patent Document 1 describes that when picture data is skipped, there is provided adjustment means for adjusting the display interval of picture data decoded without being skipped.
Further, Patent Document 2 describes a technique in which, when an input picture is not an I picture, when the immediately preceding picture data is decoded, the corresponding picture data is not decoded. Thereby, picture data other than the I picture can be decoded. As a result, the image quality is improved.

JP 2008-022475 A JP 2008-199109 A

However, the technique described in Patent Document 1 requires a new adjustment means for adjusting the display interval of picture data decoded without being skipped in the playback device, which increases costs. In addition, in the technique described in Patent Document 2, the appearance frequency of decoded picture data is not necessarily uniform among the picture data of a plurality of frames that are continuous in time series, and thus the display interval of picture data may be disturbed. There is. Therefore, there is a possibility of visually giving a bad impression to the viewer.
Further, in the techniques described in Patent Document 1 and Patent Document 2, it is determined which picture data to skip regardless of the frame rate of the playback device. For this reason, picture data may be skipped too much compared to the frame rate of the playback device.

  The playback device according to the first aspect of the present invention is a playback device that decodes and plays back encoded video data. The video data includes data in which picture data is continuous for a plurality of frames. The reproduction apparatus includes priority order assigning means and decoding means. The priority level assigning unit gives priority to the picture data included in the video data in the order of the encoded first picture data and the second picture data encoded with reference to the picture data of another frame. Give a ranking. The decoding means selects and decodes the predetermined number of picture data in descending order of priority.

In the first aspect of the present invention, the video data is sequentially processed in the order of the first picture data encoded by the priority assigning means and the second picture data encoded with reference to the picture data of another frame. A priority is given to the picture data included in the picture. Then, the decoding means selects and decodes a predetermined number of picture data in descending order of priority. Therefore, the appearance frequency of decoded picture data can be made as uniform as possible among the picture data of a plurality of frames that are continuous in time series. Therefore, disturbance in the display interval of picture data can be suppressed. Thereby, it can prevent giving a viewer a bad impression visually.
Further, the decoding means selects and decodes a predetermined number of picture data in descending order of priority. In other words, picture data of an arbitrary number of frames can be decoded by the decoding means. Therefore, it is possible to decode the picture data having the number of frames according to the frame rate of the playback device by the decoding means.
Therefore, it is possible to prevent the viewer from giving a bad impression visually in accordance with the frame rate of the playback device.

  The reproduction processing method according to the second aspect of the present invention is a reproduction processing method for decoding and reproducing encoded video data. The video data includes data in which picture data is continuous for a plurality of frames. The reproduction processing method includes a priority order assigning process and a decoding process. In the prioritization process, the first picture data encoded and the second picture data encoded with reference to the picture data of another frame are sequentially added to the picture data included in the video data. Priorities are given. In the decoding process, a predetermined number of frames of the picture data are selected and decoded in descending order of priority.

In the second aspect of the present invention, in the priority assigning process, the video data is in the order of the encoded first picture data and the encoded second picture data with reference to the picture data of another frame. A priority is given to the picture data included in the picture. In the decoding process, picture data of a predetermined number of frames is selected and decoded in descending order of priority. Therefore, the appearance frequency of decoded picture data can be made as uniform as possible among the picture data of a plurality of frames that are continuous in time series. Therefore, disturbance in the display interval of picture data can be suppressed. Thereby, it can prevent giving a viewer a bad impression visually.
Further, in the decoding process, picture data of a predetermined number of frames is selected and decoded in descending order of the priority. In other words, picture data of an arbitrary number of frames can be decoded in the decoding process. Therefore, in the decoding process, it is possible to decode the picture data having the number of frames according to the frame rate of the playback device.
Therefore, it is possible to prevent the viewer from giving a bad impression visually in accordance with the frame rate of the playback device.

  According to the present invention, it is possible to prevent a viewer from giving a visual bad impression in accordance with the frame rate of the playback apparatus.

It is a block diagram which shows an example of a structure of the reproducing | regenerating apparatus concerning Embodiment 1 of this invention. It is a figure explaining video data. It is a figure explaining the reproduction | regeneration processing method concerning this invention. It is a figure explaining the reproduction | regeneration processing method concerning Embodiment 1 of this invention. It is a figure explaining the reproduction | regeneration processing method concerning Embodiment 1 of this invention. It is a flowchart explaining an example of the reproduction | regeneration processing method concerning Embodiment 1 of this invention. It is a block diagram which shows an example of a structure of the reproducing | regenerating apparatus concerning Embodiment 2 of this invention. It is a figure explaining the reproduction | regeneration processing method concerning Embodiment 2 of this invention. It is a figure explaining the reproduction | regeneration processing method concerning Embodiment 2 of this invention. It is a figure explaining the reproduction | regeneration processing method concerning Embodiment 2 of this invention.

Embodiment 1 FIG.
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram showing an example of the configuration of the playback apparatus 100 according to the first embodiment of the present invention. As shown in FIG. 1, the playback apparatus 100 includes an input unit 1, a header reference unit 2, a reordering unit 3, a priority order assigning unit (priority order giving unit) 4, a picture selection unit (decoding unit) 5, and a decoding unit ( Decoding means) 6, an output unit 7 and the like.
In addition, the playback device 100 includes a control unit (not shown) including an unillustrated FPGA (Field Programmable Gate Array), and the FPGA stores various programs for controlling each unit of the playback device 100. . And a control part controls each part of the reproducing | regenerating apparatus 100 by running the said various programs. The control unit may include an LSI (Large Scale Integration) or the like instead of the FPGA. When the control unit includes an FPGA, various programs stored in the FPGA can be rewritten.

  The input unit 1 is, for example, a storage medium such as Flash Memory or HDD (Hard Disc Drive), an input interface connected to a communication module such as Wi-Fi (registered trademark), a mobile phone network, or a TV. The converted video data is input to the playback apparatus 100 via the input unit 1. Here, the video data includes a plurality of frames of picture data continuous in time series. The video data input to the playback apparatus 100 via the input unit 1 is, for example, H.264. It is encoded by an encoding method such as H.264 / AVC method. Note that the video data input to the playback device 100 via the input unit 1 may be encoded by the MPEG method or the like.

  More specifically, as shown in FIG. 2, the video data is data in which a data set including GOP (Group Of Pictures) and SH (Sequence Header) is continuous in time series. Each GOP includes one or more I pictures, a plurality of P pictures, and a plurality of B pictures. In other words, the video data includes a plurality of frames of picture data continuous in time series.

  The header reference unit 2 refers to the NAL header in the SH included in the video data, and extracts information regarding the type of picture data included in the GOP. Specifically, the header reference unit 2 refers to nal_ref_idc, nal_unit_type, and slice_type. Then, the header reference unit 2 determines whether each picture data included in the GOP is an I picture (Intra Picture), a P picture (Predictive Picture), or a B picture (Bi-directional Predictive Picture). The header reference unit 2 inputs the determination result information to the reordering unit 3.

  The reordering unit 3 performs a reordering process on the video data input from the input unit 1 based on the determination result information input from the header reference unit 2. Specifically, as shown in FIG. 3, the reordering unit 3 rearranges the pieces of picture data in the display order. In FIG. 3 to FIG. 5, the reference destination of each picture data is indicated by an arrow. Then, the reordering unit 3 inputs the determination result information input from the header reference unit 2 and the video data subjected to the reordering process to the priority level assigning unit 4.

The priority level assigning unit 4 gives a priority level to each picture data included in the video data input from the reordering unit 3. Specifically, the priority level assigning unit 4 is included in the video data in the order of the encoded first picture data and the encoded second picture data with reference to the picture data of another frame. Priorities are assigned to each picture data. More specifically, for example, as shown in FIG. 4, the priority level assigning unit 4 includes an I picture, a P picture referring to the I picture, a P picture referring to the P picture, a B picture referring to the I picture, and I Priorities are assigned to each picture data included in the video data in the order of a B picture that references a P picture that refers to a picture and a B picture that refers to a P picture that refers to a P picture. In FIG. 4, the priority order is indicated by a number. In FIG. 4, it shows that a priority is so high that a number is small.
In this embodiment, the priority level assigning unit 4 sets a predetermined number of frames, which is the number of frames of picture data decoded by the decoding unit 6, based on the frame rate of the playback apparatus 100 and the like. However, the present invention is not limited to this, and the predetermined number of frames may be determined in advance or may be set by another method.
In the present embodiment, the priority level assigning unit 4 gives priority levels to the picture data included in the GOP for each GOP.
Then, the priority level assigning unit 4 inputs the video data to which the priority order is given to the picture selecting unit 5.

The picture selection unit 5 selects picture data of a predetermined number of frames in descending order of priority. Here, the predetermined number of frames is determined based on the frame rate of the playback apparatus 100 or the like. In other words, the picture selection unit 5 selects picture data by the number of frames that matches the frame rate of the playback device 100 in descending order of priority. In the present embodiment, for each GOP, the picture selection unit 5 selects picture data corresponding to the number of frames suitable for the frame rate of the playback device 100 among the picture data included in the GOP. For example, as shown in FIG. 5, when 15 frames of picture data are included in a GOP and only 5 frames are decoded by the decoding unit 6, the picture selection unit 5 selects the highest priority (in FIG. 5). In order of increasing numbers, picture data up to 5 frames are selected. In FIG. 5, unselected picture data is indicated by hatching.
Also, the picture selection unit 5 designates unselected picture data (pictures with hatched lines in FIG. 5) as dummy pictures. As a result, the picture selection unit 5 prevents the decoding unit 6 from decoding the picture data designated as a dummy picture.

  The decoding unit 6 decodes the picture data selected by the picture selection unit 5. The decoding unit 6 inputs the decoded video data to the output unit 7.

  The output unit 7 is, for example, an output interface connected to a display device such as an LCD (Liquid Crystal Display) or TV, or a communication module such as Wi-Fi (registered trademark) or Wireless HDMI (High-Definition Multimedia Interface). The video data decoded by the decoding unit 6 is input to an external device such as a display device via the output unit 7.

Next, a playback processing method in the playback apparatus 100 according to the first embodiment of the present invention will be described with reference to the flowchart shown in FIG.
First, H.P. Video data encoded in the H.264 format is input to the playback apparatus 100 (step S1).

  Next, the header reference unit 2 refers to the NAL header, determines the type of picture data included in the GOP, and inputs the determination result information to the reordering unit 3. (Step S2).

  Next, the reordering unit 3 rearranges the picture data in the display order based on the determination result information input from the header reference unit 2 (step S3). Then, the reordering unit 3 inputs the determination result information input from the header reference unit 2 and the video data subjected to the reordering process to the priority level assigning unit 4.

Next, the priority level assigning unit 4 sets the number of frames to be decoded by the decoding unit 6 based on the frame rate of the playback apparatus 100 (step S4).
Next, the priority level assigning unit 4 assigns a priority level to each picture data included in the video data input from the reordering unit 3 (step S5). Then, the priority level assigning unit 4 inputs the video data to which the priority order is given to the picture selecting unit 5.

Next, the picture selection unit 5 selects picture data of a predetermined number of frames in descending order of priority, and designates the remaining picture data as dummy pictures (step S6).
Next, the decoding unit 6 decodes the picture data selected by the picture selection unit 5 (step S7).

  Next, the decoded video data is input from the decoding unit 6 to the external device via the output unit 7 (step S8).

According to the reproduction apparatus 100 and the reproduction processing method according to the first embodiment of the present invention described above, the priority assigning unit 4 refers to the encoded first picture data and picture data of other frames. The priority order is given to the picture data included in the video data in the order of the encoded second picture data. Then, the picture selection unit 5 selects a predetermined number of frames of picture data in descending order of priority, and the decoding unit 6 decodes the picture data selected by the picture selection unit 5. Therefore, the appearance frequency of decoded picture data can be made as uniform as possible among the picture data of a plurality of frames that are continuous in time series. As a result, disturbance in the display interval of picture data can be suppressed. Therefore, it is possible to prevent the viewer from giving a visual bad impression.
Further, the picture selection unit 5 selects a predetermined number of frames of picture data in descending order of priority, and the decoding unit 6 decodes the picture data selected by the picture selection unit 5. In other words, the decoding unit 6 can decode picture data of an arbitrary number of frames. Therefore, the decoding unit 6 can decode the picture data having the number of frames according to the frame rate of the playback device 100.
Therefore, it is possible to prevent the viewer from giving a bad visual impression in accordance with the frame rate of the playback apparatus 100.

Also, the first picture data is an I picture, the second picture data is a P picture and a B picture, and the priority level assigning unit 4 selects an I picture, a P picture that refers to the I picture, and a P picture. Priority is given to the picture data included in the video data in the order of the P picture to be referenced, the B picture to refer to the I picture, the B picture to refer to the P picture to refer to the I picture, and the B picture to refer to the P picture to refer to the P picture. Give a ranking.
As a result, H.C. The present invention can also cope with the case of reproducing video data encoded by an encoding method such as H.264 / AVC method.

Furthermore, the predetermined number of frames of picture data decoded by the decoding unit 6 is determined based on the frame rate of the playback apparatus 100 and the like.
As a result, the picture data is skipped by the number of frames adapted to the frame rate of the playback apparatus 100, and it is not necessary to skip the picture data.

Embodiment 2. FIG.
FIG. 7 is a block diagram showing an example of the configuration of the playback device 200 according to the second embodiment of the present invention. As shown in FIG. 7, the playback apparatus 200 according to the second embodiment has the same configuration as the playback according to the first embodiment except for the priority level assigning unit (priority level giving unit) 40 and the picture selection unit (decoding unit) 50. Since it is the same as that of the apparatus 100, the same reference numerals are given and the description thereof is omitted.

The priority order assigning unit 40 assigns a priority order to each picture data included in the video data input from the reordering unit 3. Specifically, the priority level assigning unit 4 is included in the video data in the order of the encoded first picture data and the encoded second picture data with reference to the picture data of another frame. Priorities are assigned to each picture data. More specifically, for example, as illustrated in FIG. 8, the priority level assigning unit 4 first includes an I picture, a P picture referring to the I picture, and a P picture referring to the P picture in the order of the video data. A priority is assigned to each picture data to be recorded. Next, the priority level assigning unit 40 gives priority levels to a plurality of B pictures included in the video data.
Specifically, the predetermined number of frames, which is the number of frames of picture data decoded by the decoding unit 6, is Y, the number of I picture frames included in the video data is Ix, and the number of P picture frames included in the video data is Px. When the number of B picture frames included in the video data is Bx and the number of B picture frames decoded by the decoding unit 6 is By, By = Y−Ix−Px. When the priority order assigning unit 40 assigns a priority order to the B picture, the decoding unit 6 decodes the B picture included in the video data at a rate of one frame per Bx / By frame. Give priority to picture data. In FIG. 8, the priority is indicated by a number. In FIG. 8, the smaller the number, the higher the priority.

In this embodiment, the predetermined number of frames (that is, the value of Y) that is the number of frames of picture data decoded by the decoding unit 6 is set by the priority order assigning unit 40 based on the frame rate of the playback device 200 and the like. Is the value to be However, the present invention is not limited to this, and the predetermined number of frames may be determined in advance or may be set by another method.
In the present embodiment, the priority order assigning unit 40 assigns a priority order to the picture data included in the GOP for each GOP.
Then, the priority order assigning unit 40 inputs the video data assigned the priority order to the picture selection unit 50.

  For example, when the number of I-picture frames included in one GOP is 1, the number of P-picture frames is 4, the number of B-picture frames is 10, and the predetermined number of frames decoded by the decoding unit 6 is 10 frames. Y = 10, Ix = 1, Px = 4, Bx = 10, and By = 10−1−4 = 5. Therefore, Bx / By = 2. Then, as shown in FIG. 9, the priority level assigning unit 40 gives priority levels to the B pictures along the sequence of the picture data after the reordering process at a rate of one frame per two frames.

Further, when the number of I picture frames included in one GOP is 1, the number of P picture frames is 4, the number of B picture frames is 10, and the predetermined number of frames decoded by the decoding unit 6 is 8 frames, Y = 8, Ix = 1, Px = 4, Bx = 10, and By = 8-1-4 = 3. Therefore, the quotient of Bx / By = 10/3 = 3. In this case, the number after the decimal point is rounded down. Then, as shown in FIG. 10, the priority level assigning unit 40 gives priority levels to the B pictures along the sequence of the reordered picture data at a rate of 1 frame per 3 frames.
In this embodiment, as shown in FIGS. 9 and 10, the priority level assigning unit 40 prioritizes only picture data to be decoded by the decoding unit 6, that is, only picture data within a predetermined number of frames. Give a ranking. In other words, the priority level assigning unit 40 does not give a priority level to the picture data that is not to be decoded by the decoding unit 6.

The picture selection unit 50 selects picture data of a predetermined number of frames in descending order of priority. Here, the predetermined number of frames is determined based on the frame rate of the playback apparatus 200 and the like. In other words, the picture selection unit 50 selects picture data by the number of frames that matches the frame rate of the playback device 200 in descending order of priority. In the present embodiment, for each GOP, the picture selection unit 50 selects picture data for the number of frames suitable for the frame rate of the playback device 200 out of the picture data included in the GOP. For example, as shown in FIG. 9, when 15 frames of picture data are included in a GOP and only 10 frames are decoded, the picture selection unit ** is given priority (in order of increasing numbers in FIG. 9). Select picture data up to 10 frames. In FIG. 9, unselected picture data is indicated by hatching. Also, for example, as shown in FIG. 10, when 15 frames of picture data are included in the GOP and only 8 frames are decoded, the picture selection unit 50 determines the priority (in order of increasing numbers in FIG. 10). Then, picture data up to 8 frames is selected. In FIG. 10, unselected picture data is indicated by hatching.
In addition, the picture selection unit 50 designates unselected picture data (pictures hatched in FIG. 9) as a dummy picture. Thereby, the picture selection unit 50 prevents the decoding unit 6 from decoding the picture data designated as the dummy picture.
Note that the flow of the reproduction processing method in the reproduction apparatus 200 according to the second embodiment is the same as the flow of the reproduction processing method in the reproduction apparatus 100 according to the first embodiment, and thus description thereof is omitted.

According to the playback device 200 and the playback processing method according to the second embodiment of the present invention described above, the priority order assigning unit 40 includes the I picture, the P picture that refers to the I picture, the P picture that refers to the P picture, In the order of B pictures, priorities are assigned to the picture data included in the video data, and the priority assigning unit 40 assigns priority to the video data at a rate of one frame per Bx / By frame when giving priority to the B pictures. A priority is given to the picture data of the B picture so that the included B picture is decoded by the decoding unit 60. “Bx / By” means a quotient obtained by dividing Bx by By.
Thereby, the appearance frequency of the decoded B picture among the picture data of a plurality of frames which are continuous in time series can be made more surely uniform. Therefore, disturbance in the display interval of picture data can be more reliably suppressed. As a result, it is possible to more surely prevent the viewer from giving a visual bad impression.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention.

100, 200 Playback device 4, 40 Priority level giving unit (priority level giving means)
5, 50 Picture selection unit (decoding means)
6 Decoding unit (decoding means)

Claims (8)

A playback device for decoding and playing back encoded video data,
The video data includes data in which picture data is continuous for a plurality of frames,
Prioritization for giving priority to the picture data included in the video data in the order of the encoded first picture data and the second picture data encoded with reference to the picture data of other frames Means,
Decoding means for decoding a predetermined number of picture data in descending order of priority;
A playback device comprising: The first picture data is an I picture (Intra Picture),
The second picture data is a P picture (Predictive Picture) and a B picture (Bi-directional Predictive Picture),
The priority assigning means includes: an I picture, a P picture that refers to the I picture, a P picture that refers to the P picture, a B picture that refers to the I picture, a B picture that refers to the P picture that refers to the I picture, and a P picture The playback apparatus according to claim 1, wherein priority is given to the picture data included in the video data in order of a B picture that refers to a P picture to be referenced. The first picture data is an I picture (Intra Picture),
The second picture data is a P picture (Predictive Picture) and a B picture (Bi-directional Predictive Picture),
The priority order assigning means assigns a priority order to the picture data included in the video data in the order of an I picture, a P picture referring to the I picture, a P picture referring to the P picture, and a B picture,
The predetermined number of frames is Y, the number of I picture frames included in the video data is Ix, the number of P picture frames included in the video data is Px, the number of B picture frames included in the video data is Bx, When the number of frames of the B picture to be decoded by the decoding means is By, By = Y−Ix−Px,
The prioritizing means assigns a picture of a B picture so that when the priority order is assigned to a B picture, the B picture included in the video data is decoded by the decoding means at a rate of one frame per Bx / By frame. The reproducing apparatus according to claim 1, wherein priority is given to the data.   The playback apparatus according to any one of claims 1 to 3, wherein the predetermined number of frames of the picture data decoded by the decoding unit is determined based on a frame rate of the playback apparatus. A reproduction processing method for decoding and reproducing encoded video data,
The video data includes data in which picture data is continuous for a plurality of frames,
Prioritization for giving priority to the picture data included in the video data in the order of the encoded first picture data and the second picture data encoded with reference to the picture data of other frames Processing,
A decoding process for decoding the picture data of a predetermined number of frames in descending order of priority;
A reproduction processing method comprising: The first picture data is an I picture (Intra Picture),
The second picture data is a P picture (Predictive Picture) and a B picture (Bi-directional Predictive Picture),
In the prioritization process, an I picture, a P picture that refers to the I picture, a P picture that refers to the P picture, a B picture that refers to the I picture, a B picture that refers to the P picture that refers to the I picture, and a P picture 6. The reproduction processing method according to claim 5, wherein priority is given to the picture data included in the video data in order of a B picture that refers to a P picture to be referred to. The first picture data is an I picture (Intra Picture),
The second picture data is a P picture (Predictive Picture) and a B picture (Bi-directional Predictive Picture),
In the priority order assigning process, priority is given to the picture data included in the video data in the order of I picture, P picture referring to the I picture, P picture referring to the P picture, and B picture,
The predetermined number of frames is Y, the number of I picture frames included in the video data is Ix, the number of P picture frames included in the video data is Px, the number of B picture frames included in the video data is Bx, When the number of frames of the B picture to be decoded by the decoding means is By, By = Y−Ix−Px,
In the prioritizing process, when prioritizing a B picture, a picture of the B picture is so decoded that the B picture included in the video data is decoded in the decoding process at a rate of one frame per Bx / By frame. The reproduction processing method according to claim 5, wherein priority is given to the data.   The reproduction processing method according to claim 5, wherein the predetermined number of frames of the picture data decoded in the decoding process is determined based on a frame rate of the reproduction device.

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