JP2024041262A - Moving image playing back apparatus and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To present a playing back section in which a viewer does not concentrate on a moving image.

SOLUTION: A moving image playing back apparatus comprises: a moving image playing back section which displays a moving image on a display device; a biological information acquisition section which acquires biological information on viewers viewing the moving image; a concentration determination section which determines whether or not the viewers concentrate on the moving image on the basis of the biological information; a result recording section which records a playing back section in which the moving image is divided by a time base and a determination result by the concentration determination section in association with each other; and a result display section which displays a viewing result expressing the playing back section indicating the determination result indicating that the viewers do not concentrate on the moving image on the display device after finishing the reproduction of the moving image.

SELECTED DRAWING: Figure 4

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a video playback device and a program.

Video distribution services that stream video content through communication networks such as the Internet are used. In video distribution services, there is a shift from a method of streaming distribution using a dedicated server using a dedicated protocol to a method of streaming distribution using a general-purpose server using a general-purpose protocol.

For example, Non-Patent Document 1 discloses the international standard MPEG-DASH (Moving Picture Experts Group - Dynamic Adaptive Streaming over HTTP, ISO/IEC 23009-1). MPEG-DASH was formulated with the intention of unifying streaming distribution methods. In MPEG-DASH, streaming is distributed by a general-purpose web server using the HTTP (Hypertext Transfer Protocol).

Mitsuhiro Hirabayashi, "Next generation video distribution technology "MPEG-DASH" technology overview, standardization and related technology trends", Journal of the Institute of Image Information and Television Engineers, Vol. 67, No. 2, pp. 109-115, 2013.

However, the conventional technology has a problem in that even if there is a playback section in which the viewer was not concentrating on the video, it is difficult to re-watch the video after the viewer has finished viewing the video. For example, by streaming video using a general-purpose protocol, it is now possible to watch videos in a variety of environments, but at the same time, events are increasingly occurring in the surroundings that impede concentration on video viewing. . If there is a playback section in which the viewer was not concentrating on the video, the viewer may not be able to fully understand the content of the video.

In view of the above technical problems, one aspect of the present invention aims to present a playback section in which the viewer was not concentrating on the video.

In order to solve the above problems, a video playback device according to one embodiment of the present invention includes: a video playback unit that displays a video on a display device; a biometric information acquisition unit that acquires biometric information of a viewer who views the video; A concentration determination unit that determines whether the viewer is concentrating on a video based on biological information; and a result recording unit that associates and records the playback section obtained by dividing the video along the time axis and the determination result by the concentration determination unit. and a result display unit that displays, on a display device, a viewing result representing a playback section in which the determination result indicates that the video is not concentrated after the video has been played.

According to one aspect of the present invention, it is possible to present playback sections in which the viewer was not concentrating on the video.

FIG. 2 is a conceptual diagram showing an example of a streaming distribution method. FIG. 1 is a block diagram showing an example of the overall configuration of a video distribution system. FIG. 2 is a block diagram showing an example of the hardware configuration of a computer. FIG. 1 is a block diagram showing an example of a functional configuration of a video distribution system. It is a flowchart which shows an example of the processing procedure of a video reproduction method. FIG. 3 is a conceptual diagram showing an example of control information. It is a conceptual diagram which shows an example of a determination result. It is a conceptual diagram which shows an example of a viewing result.

Embodiments of the present invention will be described below with reference to the accompanying drawings. Note that, in this specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals and redundant explanation will be omitted.

[Embodiment]
<Summary>
In recent years, in streaming distribution of video content on the Internet, there has been a shift from a method using a dedicated protocol using a dedicated server to a method using the HTTP protocol using a general-purpose web server. By streaming distribution using a general-purpose protocol, it is possible to distribute video content to a variety of devices.

A method of streaming distribution using the HTTP protocol with optimal quality depending on the communication state of the network is called adaptive streaming. In adaptive streaming, proprietary technologies by IT (Information Technology) vendors are becoming widespread, while MPEG-DASH, an international standard intended to unify streaming distribution methods, has been established. The basic concept of both distribution technologies is the same, and video content is streamed as follows.

The web server prepares segments that make up video content and a manifest file. A segment is video data obtained by encoding video content with one or more qualities (for example, screen size, bit rate, etc.) and dividing it into electronic files each having a length of several seconds to several tens of seconds. The manifest file is an electronic file in which attribute information and position information of each segment are described.

The receiving terminal selects the optimal quality from the manifest file in a timely manner, taking into consideration the screen size of the display device, the status of the network reception band, etc., and sequentially receives segments encoded with that quality. The receiving terminal decodes the segments received from the web server, joins them together into a single video content, and plays the video content on a display device or the like.

FIG. 1 is a conceptual diagram showing an example of a streaming distribution method. As shown in FIG. 1, an encoder first encodes video content in multiple qualities, and generates segments divided by several seconds to several tens of seconds for each quality. In the example of Figure 1, the encoder encodes segments 1 to 4 with low quality..., segments 1' to 4' encoded with medium quality, segments 1'' to 4'' encoded with high quality...・is generated. The manifest file describes positional information such as URL (Uniform Resource Locator) of each segment, and attribute information such as bit rate and image size of each quality. The segments and manifest files generated by the encoder are provided to a web server.

The receiving terminal receives the manifest file from the web server, and grasps the segment configuration and attribute information of each quality based on the manifest file. Next, the receiving terminal selects quality for each segment based on the screen size of the display device and the status of the network reception band, and receives the segment using the HTTP protocol. Subsequently, the receiving terminal connects the received segments in order according to the manifest file and plays them on the display device. In this way, the receiving terminal can receive and continue playing a series of segments constituting one piece of video content.

The quality selection method in adaptive streaming is not defined in the standard. For example, a method is known in which quality is selected based on the state of the network reception band, the remaining amount of buffer provided in the reception terminal, etc. (see, for example, Reference 1). Also, for example, each time a receiving terminal receives a segment, it determines the current transmission rate, obtains statistical information related to the expected future transmission rate as a function of the current transmission rate, and derives it from the statistical information. A method is known in which subsequent segments are received according to a set target transmission rate (for example, see Reference 2).

[Reference 1] Hongzi Mao, Ravi Netravali, Mohammad Alizadeh, "Neural Adaptive Video Streaming with Pensieve", SIGCOMM, pp. 197-210, Aug. 2017.
[Reference 2] Special Publication No. 2016-506644

In recent years, it has become possible to view video content in various environments, and events that prevent people from concentrating on video viewing are increasingly occurring in their surroundings. For example, if you receive stimuli unrelated to video viewing (e.g. notifications from SNS (Social Networking Service), etc.) or if you are not feeling well, you may be unable to concentrate on watching videos, and even if you are watching video content, you may not be able to fully understand the content. There are some things I don't understand. In such cases, the viewing rate may improve on the surface, but the viewer's understanding is not being promoted, and it cannot be said that the video is actually being viewed.

An embodiment of the present invention aims to facilitate substantial understanding of video content being viewed in a video distribution system that distributes video content over a communication network. In one embodiment of the present invention, a playback section in which it is determined that the viewer is not concentrating on video viewing based on brain waves or biological information such as a facial image is recorded and presented after the video viewing is finished. This allows the viewer to understand the playback section in which they were not concentrating on viewing the video, and by rewatching the playback section, it is possible to promote understanding of the content of the video.

As biological information from which the degree of concentration can be estimated, for example, brain waves or facial images are known. It is known that the degree of concentration can be estimated from, for example, the number of blinks or facial expressions (for example, see Reference 3). Further, for example, by detecting line of sight from a face image, the target of concentration can be estimated. It is known that emotions can be estimated from, for example, brain waves and facial expressions (for example, see Reference 4).

[Reference 3] Unexamined Japanese Patent Publication No. 2021-170315 [Reference 4] Kiyohisa Natsume, “Is there a brain wave that can be used as an indicator of boredom? ", Scientific research grant project research results report, issue number 22650205, 2011

Conventionally, the problem with measuring brain waves has been that the act of measuring causes a lot of stress on the viewer. For example, causes of stress include the large size of the measuring device, restrictions on movement during measurement, and the fact that measurement takes a long time. In recent years, with the development of earphone-type electroencephalogram measuring devices, it has become possible to measure electroencephalograms without placing a psychological burden on viewers (for example, see Reference 5).

[Reference 5] Toppan Printing Co., Ltd., "Toppan Printing begins sales of earphone-type brain wave device "b-tone"", [online], [searched on August 3, 2020], Internet <URL: https: //www.toppan.co.jp/news/2021/09/newsrelease210907_1.html＞

<Overall configuration of video distribution system>
The overall configuration of the video distribution system in this embodiment will be described with reference to FIG. 2. FIG. 2 is a block diagram showing an example of the overall configuration of the video distribution system in this embodiment.

As shown in FIG. 2, the video distribution system 1 in this embodiment includes a video distribution server 10 and one or more video playback devices 20. The video distribution server 10 and the video playback device 20 are connected to enable data communication via a communication network N1 such as a LAN (Local Area Network) or the Internet.

The video distribution server 10 is an information processing device such as a personal computer, workstation, or server that distributes video content via the communication network N1. The video distribution server 10 transmits video content to the video playback device 20 in response to a request from the video playback device 20.

The video playback device 20 is an electronic device, such as a television receiver, set-top box, personal computer, or smartphone, on which a viewer views video content. The video playback device 20 requests the video distribution server 10 to distribute video content in response to a viewer's operation, and plays the video content received from the video distribution server 10 on the display device.

Note that the overall configuration of the video distribution system 1 shown in FIG. 2 is one example, and there may be various system configuration examples depending on the usage and purpose. For example, the video distribution server 10 may be realized by a plurality of computers, or may be realized as a cloud computing service.

<Hardware configuration of video distribution system>
The hardware configuration of the video distribution system 1 in this embodiment will be described with reference to FIG.

≪Computer hardware configuration≫
The video distribution server 10 and the video playback device 20 in this embodiment are realized by, for example, a computer. FIG. 3 is a block diagram showing an example of the hardware configuration of the computer in this embodiment.

As shown in FIG. 3, the computer 500 in this embodiment includes a CPU (Central Processing Unit) 501, a ROM (Read Only Memory) 502, a RAM (Random Access Memory) 503, an HDD (Hard Disk Drive) 504, It has an input device 505, a display device 506, a communication I/F (Interface) 507, and an external I/F 508. CPU501, ROM502, and RAM503 form what is called a computer. Each piece of hardware in the computer 500 is interconnected via a bus line 509. Note that the input device 505 and the display device 506 may be connected to an external I/F 508 for use.

The CPU 501 is a computing device that reads programs and data from a storage device such as the ROM 502 or the HDD 504 onto the RAM 503 and executes processing to realize the overall control and functions of the computer 500.

The ROM 502 is an example of a nonvolatile semiconductor memory (storage device) that can retain programs and data even when the power is turned off. The ROM 502 functions as a main storage device that stores various programs, data, etc. necessary for the CPU 501 to execute various programs installed on the HDD 504 . Specifically, the ROM 502 stores data such as boot programs such as BIOS (Basic Input/Output System) and EFI (Extensible Firmware Interface) that are executed when the computer 500 is started, OS (Operating System) settings, and network settings. is stored.

The RAM 503 is an example of a volatile semiconductor memory (storage device) whose programs and data are erased when the power is turned off. The RAM 503 is, for example, DRAM (Dynamic Random Access Memory) or SRAM (Static Random Access Memory). The RAM 503 provides a work area where various programs installed on the HDD 504 are expanded when the CPU 501 executes them.

The HDD 504 is an example of a non-volatile storage device that stores programs and data. The programs and data stored in the HDD 504 include an OS, which is basic software that controls the entire computer 500, and applications that provide various functions on the OS. Note that instead of the HDD 504, the computer 500 may use a storage device that uses flash memory as a storage medium (e.g., an SSD: Solid State Drive, etc.).

The input device 505 is a touch panel used by the user to input various signals, operation keys or buttons, a keyboard or mouse, a microphone used to input sound data such as voice, or the like.

The display device 506 includes a display such as a liquid crystal or organic EL (Electro-Luminescence) that displays a screen, a speaker that outputs sound data such as audio, and the like.

The communication I/F 507 is an interface that connects to a communication network and enables the computer 500 to perform data communication.

The external I/F 508 is an interface with external devices. Examples of external devices include a drive device 510.

The drive device 510 is a device for setting the recording medium 511. The recording medium 511 here includes media that record information optically, electrically, or magnetically, such as CD-ROMs, flexible disks, and magneto-optical disks. The recording medium 511 may also include semiconductor memory that records information electrically, such as ROM and flash memory. This allows the computer 500 to read and/or write to the recording medium 511 via the external I/F 508.

Note that the various programs installed on the HDD 504 are, for example, when the distributed recording medium 511 is set in the drive device 510 connected to the external I/F 508, and the various programs recorded on the recording medium 511 are read by the drive device 510. It is installed by Alternatively, various programs to be installed on the HDD 504 may be installed by being downloaded from a network different from the communication network via the communication I/F 507.

<Functional configuration of video distribution system>
The functional configuration of the video distribution system in this embodiment will be described with reference to FIG. 4. FIG. 4 is a block diagram showing an example of the functional configuration of the video distribution system 1 in this embodiment.

<Video distribution server functional configuration>
As shown in FIG. 4, the moving image distribution server 10 in this embodiment includes a moving image distribution unit 101, a control information distribution unit 102, a moving image storage unit 111, and a control information storage unit 112.

The video distribution unit 101 and the control information distribution unit 102 are realized, for example, by a process executed by the CPU 501 of a program loaded onto the RAM 503 from the HDD 504 shown in FIG. 3. The video storage unit 111 and the control information storage unit 112 are realized, for example, by using the HDD 504 shown in FIG. 3.

The video storage unit 111 stores video content to be distributed to the video playback device 20. The video content in this embodiment is a set of segments obtained by encoding one video data for each of a plurality of predetermined qualities and dividing it into a plurality of playback sections along the time axis.

The control information storage unit 112 stores control information used to reproduce the video content stored in the video storage unit 111. The control information in this embodiment is information that associates playback time, segment position information, and expected emotional value. An example of control information in this embodiment is a manifest file.

The segment location information is, for example, a URL indicating the location of the electronic file corresponding to the segment. The expected emotion value is information representing the emotion that is expected to occur when viewing the segment. The expected value of emotion may be set in advance by a video content producer or the like.

The control information storage unit 112 further stores a distributed list in which information regarding segments distributed to the video playback device 20 is recorded. The distributed list is stored for each video playback device 20.

The video distribution unit 101 transmits the segments stored in the video storage unit 111 to the video playback device 20 in response to the segment acquisition request received from the video playback device 20. The video distribution unit 101 records information regarding the segment transmitted to the video playback device 20 in the distributed list stored in the control information storage unit 112.

The control information distribution unit 102 transmits the control information stored in the control information storage unit 112 to the video playback device 20 in response to the control information acquisition request received from the video playback device 20.

≪Functional configuration of video playback device≫
As shown in FIG. 4, the video playback device 20 in this embodiment includes a control information acquisition section 201, a video acquisition section 202, a buffer section 203, a video playback section 204, a biological information acquisition section 205, and a concentration determination section 206. , a result recording section 207, a result display section 208, a control information storage section 211, and a determination result storage section 212.

For example, the control information acquisition unit 201, the video acquisition unit 202, the buffer unit 203, the video playback unit 204, the biological information acquisition unit 205, the concentration determination unit 206, the result recording unit 207, and the result display unit 208 are shown in FIG. This is realized by the process of causing the CPU 501 to execute a program loaded onto the RAM 503 from the HDD 504. The control information storage unit 211 and the determination result storage unit 212 are realized using, for example, the HDD 504 shown in FIG. 3.

The control information storage unit 211 stores control information received from the video distribution server 10. The control information storage unit 211 stores control information regarding the video content each time the video content is played back.

The determination result storage unit 212 stores a determination result list in which the determination results determined by the centralized determination unit 206 are recorded. The determination result list is a list that is generated every time video content is played back and records segments and determination results in association with each other.

The control information acquisition unit 201 transmits a control information acquisition request to the video distribution server 10 in response to a video playback operation by the viewer. The control information acquisition unit 201 stores the control information received from the video distribution server 10 in the control information storage unit 211.

The video acquisition unit 202 transmits a segment acquisition request to the video distribution server 10 according to the control information stored in the control information storage unit 211. The video acquisition unit 202 stores the segments received from the video distribution server 10 in the buffer unit 203.

The buffer unit 203 stores the segments received from the video distribution server 10 in association with a playback start time and a playback duration time (segment length). The buffer unit 203 reads the segments according to the playback start time and sequentially outputs them to the video playback unit 204.

The video playback unit 204 obtains a segment to be played next from the buffer unit 203. The video playback unit 204 decodes the acquired segment according to the media format (video, audio, text, etc.) according to the control information stored in the control information storage unit 211. The video playback unit 204 plays back the decoded segments on the display device 506.

The biometric information acquisition unit 205 obtains biometric information of the viewer. The biological information in this embodiment is the viewer's brain waves, facial image, or the like.

The concentration determination unit 206 estimates the viewer's concentration level or emotion based on the biometric information acquired by the biometric information acquisition unit 205. The concentration determining unit 206 determines whether the viewer is concentrating on the video based on the estimated concentration level or emotion.

The result recording unit 207 records the determination result determined by the intensive determination unit 206 in the determination result list stored in the determination result storage unit 212 in association with the segment that was being reproduced at the time of determination. The result recording unit 207 associates the segment and the determination result by, for example, pairing the identification information that identifies the segment with the determination result.

After the video playback unit 204 finishes playing the video content, the result display unit 208 generates a viewing result based on the determination result list stored in the determination result storage unit 212. The viewing result is information indicating a playback section in which the viewer was not concentrating on the video. The result display unit 208 stores the generated viewing results in the determination result storage unit 212 and displays them on the display device 506.

<Processing procedure of video distribution system>
The processing procedure of the video distribution method executed by the video distribution system 1 in this embodiment will be explained with reference to FIG. 5. FIG. 5 is a flowchart illustrating an example of the processing procedure of the video distribution method in this embodiment.

In step S1, the video playback unit 204 included in the video playback device 20 receives a video playback operation from the viewer. A video playback operation is performed by specifying video content to be played. The video playback operation is, for example, an operation of selecting desired video content from playable video content on a menu screen or the like displayed by the video playback device 20 on the display device 506.

In step S2, the control information acquisition unit 201 included in the video playback device 20 transmits a control information acquisition request to the video distribution server 10. The control information acquisition request includes identification information (hereinafter also referred to as "video ID") that identifies the video content specified in the video playback operation.

In step S3, the control information distribution unit 102 included in the video distribution server 10 receives a control information acquisition request from the video playback device 20. Next, the control information distribution unit 102 reads control information from the control information storage unit 112 based on the video ID included in the control information acquisition request. Subsequently, the control information distribution unit 102 transmits the read control information to the video playback device 20.

In step S4, the control information acquisition unit 201 included in the video playback device 20 receives control information from the video distribution server 10. Next, the control information acquisition unit 201 stores the received control information in the control information storage unit 211. Subsequently, the video playback unit 204 starts playing back the video content.

FIG. 6 is a conceptual diagram showing an example of control information in this embodiment. As shown in FIG. 6, the control information in this embodiment is information in which time, segment URL, and perception ID are associated for each quality. The quality is the quality of encoded video content. For example, if video content includes segments encoded in high quality, medium quality, and low quality, control information exists for each of high quality, medium quality, and low quality.

The time is the playback start time of the segment. The playback start time is the time elapsed from the time playback of the video content started. The segment URL is the location information of the video data corresponding to the segment.

Perception ID represents the expected value of emotion. In this embodiment, it is assumed that the perceptual ID is set according to Ekman's theory. Ekman's theory defines human emotions in terms of six basic emotions. The perception ID is, for example, one of (1) joy, (2) sadness, (3) disgust, (4) anger, (5) fear, and (6) surprise. The perceptual ID may be set in advance by a video content producer or the like.

The explanation will be returned to FIG. 5. In step S5, the video acquisition unit 202 included in the video playback device 20 determines the quality depending on the screen size of the display device 506 or the state of the communication network N1. Next, the video acquisition unit 202 transmits a segment acquisition request to the video distribution server 10 according to the control information stored in the control information storage unit 211. The segment acquisition request includes a segment URL corresponding to the determined quality.

In step S6, the video distribution unit 101 included in the video distribution server 10 receives a segment acquisition request from the video playback device 20. Next, the video distribution unit 101 reads the segment from the video storage unit 111 based on the segment URL included in the segment acquisition request. Subsequently, the video distribution unit 101 transmits the read segment to the video playback device 20. At the same time, the video distribution unit 101 records information regarding the read segment in the distributed list stored in the control information storage unit 112.

In step S7, the video acquisition unit 202 included in the video playback device 20 receives the segment from the video distribution server 10. Next, the video acquisition unit 202 stores the received segment in the buffer unit 203 in association with the playback start time and playback duration time.

The video playback unit 204 acquires segments from the buffer unit 203. The request includes the playback start time of the next segment. The reproduction start time of the next segment is the time obtained by adding the reproduction duration time to the reproduction start time of the segment currently being reproduced. The buffer unit 203 reads out the segment corresponding to the requested playback start time and outputs it to the video playback unit 204.

The video playback unit 204 decodes the segments output from the buffer unit 203 in accordance with the media format, in accordance with the control information stored in the control information storage unit 211. The video playback unit 204 outputs the decoded segments from the display device 506 in accordance with the media format.

In step S8, the biometric information acquisition unit 205 included in the video playback device 20 acquires biometric information of the viewer. Next, the biological information acquisition unit 205 sends the acquired biological information of the viewer to the centralized determination unit 206 .

When acquiring brain waves as biological information, the biological information acquisition unit 205 connects to an electroencephalogram measurement device worn by the viewer via a wired or wireless interface, and receives a signal output from the electroencephalogram measurement device. When acquiring a facial image as biological information, the biological information acquisition unit 205 controls a photographing unit such as a camera connected to the video playback device 20 to photograph a facial image of the viewer.

In step S9, the centralized determination unit 206 included in the video playback device 20 receives biometric information of the viewer from the biometric information acquisition unit 205. Next, the concentration determination unit 206 estimates the viewer's concentration level or emotion based on the viewer's biological information. Next, the concentration determining unit 206 determines whether the viewer is concentrating on the video based on the estimated concentration level or emotion. Then, the centralized determination unit 206 sends the determination result to the result recording unit 207.

When the viewer's emotion is estimated, the concentration determining unit 206 determines whether a negative change in perception has occurred. A change in negative perception indicates that when the previously estimated emotion was a positive emotion or no emotion, the currently estimated emotion has changed to a negative emotion. Examples of positive emotions are (1) joy and (6) surprise. Examples of negative emotions are (2) sadness, (3) disgust, (4) anger, and (5) fear.

When a negative change in perception occurs, the concentration determination unit 206 compares the currently estimated emotion (hereinafter also referred to as "estimated emotion value") with the expected emotion value included in the control information. If the estimated value of emotion is different from the expected value of emotion, the concentration determining unit 206 determines that the viewer is not concentrating on the video.

In other cases, the concentration determining unit 206 determines that the viewer is concentrating on the video. That is, if a negative change in perception has not occurred, or if the estimated value of emotion is the same as the expected value of emotion, the concentration determining unit 206 determines that the viewer is concentrating on the video.

When the concentration determination unit 206 estimates the viewer's concentration level, it compares the estimated concentration level (hereinafter also referred to as "estimated concentration value") with a predetermined threshold. When the estimated value of the degree of concentration is equal to or greater than the threshold, the concentration determining unit 206 determines that the viewer is concentrating on the video. On the other hand, if the estimated value of the degree of concentration is less than the threshold, the concentration determining unit 206 determines that the viewer is not concentrating on the video.

In step S10, the result recording unit 207 included in the video playback device 20 receives the determination result from the centralized determination unit 206. The result recording unit 207 records the received determination result and identification information for identifying the segment that was being reproduced at the time of determination as a set in the determination result list stored in the determination result storage unit 212 .

FIG. 7 is a conceptual diagram showing an example of a determination result list in this embodiment. As shown in FIG. 7, the determination result list in this embodiment is information in which time, segment URL, and non-concentration flag are associated.

The time is the time when the segment starts playing. The segment URL is position information of video data acquired in a segment corresponding to each time.

The non-concentration flag has a truth value that is true when the viewer is not concentrating on the video, and is false when the viewer is concentrating on the video. The non-concentration flag is set based on the determination result determined by the concentration determination unit 206 in that segment.

The explanation will be returned to FIG. 5. In step S11, the video playback unit 204 included in the video playback device 20 determines whether the playback of the video content has ended. The video playback unit 204 determines that playback has ended, for example, when the last segment of the video content is played back, or when the user performs a playback end operation. On the other hand, in other cases (for example, when there is a segment to be played next and the user has not performed an operation to end the playback), the video playback unit 204 determines that the playback has not ended.

When the video playback unit 204 determines that playback has ended (YES), the process proceeds to step S12. On the other hand, if the video playback unit 204 determines that the playback has not ended (NO), the process returns to step S5.

In step S12, the result display unit 208 included in the video playback device 20 generates viewing results based on the determination result list stored in the determination result storage unit 212. Next, the result display unit 208 stores the generated viewing results in the determination result storage unit 212. Subsequently, the result display unit 208 displays the generated viewing results on the display device 506.

FIG. 8 is a conceptual diagram showing an example of viewing results in this embodiment. As shown in FIG. 8, the viewing result in this embodiment is information in which a playback start time, a playback duration time, and a segment URL are associated. The viewing results are the results of extracting segments in which the non-concentration flag was set to true (that is, the viewer was not concentrating on the video) in the determination result list shown in FIG.

The playback start time is the playback start time of the segment for which the non-concentration flag is set to true. If there are a plurality of consecutive segments with the non-concentration flag set, the reproduction start time of the segment with the earliest reproduction start time among those segments is displayed.

The playback duration is the playback duration of the segment for which the non-concentration flag is set to true. If there are multiple consecutive segments with the non-concentration flag set, the total playback duration of these segments is displayed.

The segment URL is the segment URL of the segment whose decentralized flag is set to true. If there are a plurality of consecutive segments with the non-concentration flag set, the segment URL of the segment with the earliest playback start time among those segments is displayed.

In the example of FIG. 8, when there are multiple consecutive segments with the non-concentration flag set, the viewing results are displayed as continuous playback sections, but the display format of the viewing results is not limited to this. . For example, viewing results may be displayed that individually list information regarding segments for which the non-concentration flag has been set. Furthermore, for example, when the video content includes a plurality of chapters, viewing results may be displayed that list information regarding chapters that include segments with non-concentration flags set.

The result display unit 208 may display the viewing results at any timing after the video content has finished playing. For example, the result display unit 208 may display the viewing results immediately after the playback of the video content ends. Furthermore, for example, when a video playback operation that specifies the same video content is performed again after the video content has finished playing, the result display unit 208 may display the previous viewing results regarding that video content. good.

In step S13, the result display unit 208 included in the video playback device 20 determines whether to rewatch the video content. If the user performs a re-viewing operation, the result display unit 208 determines to re-view the video. The re-viewing operation is, for example, an operation of selecting a desired playback section from the viewing results. On the other hand, if the user performs an operation other than the re-viewing operation, the result display unit 208 determines not to re-view the video. The operation other than the re-viewing operation is, for example, a viewing end operation. The viewing end operation is, for example, an operation to close the viewing results.

When the result display unit 208 determines to rewatch the video (YES), the result display unit 208 specifies the playback start time of the selected playback section, and returns the process to step S5. On the other hand, if the result display unit 208 determines that the video is not to be viewed again (NO), it ends the process of the video playback method.

When the process returns to step S5, the video acquisition unit 202 sends a segment acquisition request including the segment URL corresponding to the specified playback start time to the video distribution server 10 according to the control information stored in the control information storage unit 211. Send. Thereby, the video playback device 20 starts playing the playback section selected by the user.

When a plurality of consecutive segments are aggregated and displayed as in the viewing results shown in FIG. to play. Note that after the playback of the specified playback section is finished, the playback of the video content may be ended, or the playback of the video content may be continued.

<Effects of embodiment>
The video playback device in this embodiment determines whether the viewer is concentrating on the video based on the biometric information acquired from the viewer while watching the video, and after the viewer finishes viewing the video, the video playback device determines whether the viewer is concentrating on the video or not. Viewing results showing the playback section where the user was not concentrating are displayed. Therefore, according to the video playback device of this embodiment, it is possible to present a playback section in which the viewer was not concentrating on the video.

The video playback device in this embodiment determines whether the viewer is concentrating on the video based on the degree of concentration or emotion estimated based on the brain waves or facial images acquired from the viewer. Therefore, according to the video playback device in this embodiment, it is possible to determine whether viewers are concentrating on the video based on an objective index.

The video playback device in this embodiment determines that the viewer is not concentrating on the video when the emotion estimated from the biometric information acquired from the viewer differs from the expected emotion value set for each playback section of the video. judge. That is, even if the emotion estimated from the viewer's biological information is a negative emotion, if the emotion is intended by the content of the video, it is determined that the viewer is concentrating on the video. Therefore, according to the video playback device of this embodiment, it is possible to accurately determine whether viewers are concentrating on the video depending on the content of the video.

The video playback device in this embodiment plays back the playback section when the viewer selects the playback section from the viewing results. Therefore, according to the video playback device according to the present embodiment, when the viewer is able to concentrate on the video, he or she can concentrate on rewatching the playback section that the viewer was not concentrating on. That is, according to the video playback device in this embodiment, it is possible to promote understanding of the content of the video.

[Modification]
In the above embodiment, an example has been described in which the video playback device 20 plays video streamed from the video distribution server 10. The video playback device 20 may play video data recorded on a recording medium. In this case, control information in which a playback time is associated with an expected emotion value may be recorded on the recording medium. The control information may be obtained from an external storage device before playing the video data.

The video playback device in this modification can play back video data recorded on a recording medium in addition to video content streamed through a communication network. Therefore, according to the video playback device in this modification, it is possible to present a playback section in which the viewer was not concentrating on the video, regardless of the distribution medium of the video content.

[supplement]
Each function of the embodiments described above can be realized by one or more processing circuits. Here, the term "processing circuit" as used herein refers to a processor programmed to execute each function by software, such as a processor implemented by an electronic circuit, or a processor designed to execute each function explained above. This includes devices such as ASICs (Application Specific Integrated Circuits), DSPs (Digital Signal Processors), FPGAs (Field Programmable Gate Arrays), and conventional circuit modules.

Although the embodiments of the present invention have been described in detail above, the present invention is not limited to these embodiments, and various modifications or variations can be made within the scope of the gist of the present invention as described in the claims. Changes are possible.

1 Video distribution system 10 Video distribution server 101 Video distribution unit 102 Control information distribution unit 111 Video storage unit 112 Control information storage unit 20 Video playback device 201 Control information acquisition unit 202 Video acquisition unit 203 Buffer unit 204 Video playback unit 205 Biometric information acquisition Section 206 Concentrated judgment section 207 Result recording section 208 Result display section 211 Control information storage section 212 Judgment result storage section

Claims (9)

a video playback unit that displays the video on a display device;
a biometric information acquisition unit that obtains biometric information of a viewer who views the video;
a concentration determination unit that determines whether the viewer is concentrating on the video based on the biological information;
a result recording unit that associates and records a playback section obtained by dividing the video on a time axis and a determination result by the intensive determination unit;
a result display unit that displays, on the display device, a viewing result representing the playback section in which the determination result indicates that the video is not concentrated after the video has been played;
A video playback device equipped with. The video playback device according to claim 1,
The concentration determining unit determines whether the viewer is concentrating on the video by comparing the degree of concentration estimated from the biological information with a predetermined threshold.
Video playback device. The video playback device according to claim 2,
The biological information acquisition unit acquires a facial image of the viewer as the biological information,
The concentration determination unit estimates the degree of concentration based on the face image.
Video playback device. The video playback device according to claim 1,
further comprising a storage unit that stores control information in which an expected value of emotion is set for each reproduction section,
The concentration determining unit determines that the viewer is not concentrating on the video when the emotion estimated from the biological information is different from the expected value set in the control information.
Video playback device. 5. The video playback device according to claim 4,
the biometric information acquisition unit acquires an electroencephalogram or a facial image of the viewer as the biometric information,
The concentration determination unit estimates the emotion based on the electroencephalogram or the facial image.
Video playback device. The video playback device according to claim 1,
The video playback unit displays the video corresponding to the playback section selected from the viewing results by the viewer on the display device.
Video playback device. The video playback device according to claim 6,
The result display section displays the viewing results before starting playback of the video when the viewing results regarding the video exist.
Video playback device. The video playback device according to claim 1,
The video playback unit plays back video content streamed through a communication network or video data recorded on a recording medium.
Video playback device. A program for causing a computer to function as the video playback device according to any one of claims 1 to 8.

Images