Source: https://patents.google.com/patent/JP4128916B2/en
Timestamp: 2019-12-11 16:56:39
Document Index: 755906341

Matched Legal Cases: ['art 14', 'art 14', 'art 14', 'art 14', 'art 23', 'art 14', 'art 14', 'art, 13', 'art, 21', 'art, 24', 'art, 25']

JP4128916B2 - Subtitle control apparatus and method, and program - Google Patents
Subtitle control apparatus and method, and program Download PDF
JP4128916B2
JP4128916B2 JP2003207621A JP2003207621A JP4128916B2 JP 4128916 B2 JP4128916 B2 JP 4128916B2 JP 2003207621 A JP2003207621 A JP 2003207621A JP 2003207621 A JP2003207621 A JP 2003207621A JP 4128916 B2 JP4128916 B2 JP 4128916B2
JP2003207621A
JP2005064599A (en
康之 正井
真人 矢島
一彦 阿部
2003-08-15 Application filed by 株式会社東芝 filed Critical 株式会社東芝
2003-08-15 Priority to JP2003207621A priority Critical patent/JP4128916B2/en
2005-03-10 Publication of JP2005064599A publication Critical patent/JP2005064599A/en
2008-07-30 Publication of JP4128916B2 publication Critical patent/JP4128916B2/en
The present invention is used in a video playback device, audio playback device, video recording / playback device, or audio recording / playback device, and is used by being embedded in or connected to a caption control device, method, and program for controlling display of closed captions and other character information. About.
When video content such as a television broadcast or a DVD is reproduced, subtitle character information (also referred to as “closed caption”) for supplementing audio information output together with the video may be provided. In the case of television broadcasting, caption character information is composed of a character multiplexed signal superimposed on a video signal, and is transmitted using an identification signal (VBI signal) inserted during a vertical blanking period. In a DVD or the like, multilingual subtitle character information can be recorded together with video and audio. In digital high-definition broadcasting, subtitle character information can be transmitted as sub-picture information.
The use of subtitle character information is considered to be effective when not only hearing-impaired persons or hearing-impaired persons but also normal-hearing persons when it is difficult to hear sound corresponding to images. For example, background noise or music (BGM) that overlaps the voice may interfere with listening to the voice content. In addition, it goes without saying that the speech speed of the voice to be heard is high, and even when the speech speed is very slow, accurate listening to the voice is difficult even for a normal listener.
A technique for controlling the display mode or the like of subtitle character information corresponding to the audio content according to the difficulty in hearing the audio content has not yet been realized in conventional video reproduction devices and information display devices.
On the other hand, several methods for analyzing voice information are known. For example, regarding the determination of background noise, a method for estimating the S / N ratio of input speech for the purpose of noise suppression (for example, see Patent Document 1 below) is known. As for the determination of musical sound, a method based on the autocorrelation coefficient of audio data (for example, see Patent Document 2 below) is known. Furthermore, with regard to speech speed estimation, a method based on a dynamic feature amount of an audio signal (for example, see Patent Document 3 below) is known.
JP 7-306695 A
Japanese Patent Laid-Open No. 5-113737
JP-A-5-289691
The present invention displays complementary subtitle character information or controls the display mode of the subtitle character information so that the content of the voice sound can be properly and reliably transmitted to the viewer even in a situation where it is difficult to hear the voice sound in the voice output. An object of the present invention is to provide a caption control device and method, and a program.
A subtitle control apparatus according to an aspect of the present invention provides a subtitle display control apparatus that controls a display mode of subtitles corresponding to sound, and an analysis unit that analyzes the sound, and difficulty in hearing a voice based on a result of the analysis. And a means for determining the display mode according to the result of the test.
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the embodiments, “voice signal” and “voice data” refer to all signals and data representing any sound including background sounds (background noise, background music, etc.) that are not limited to human voices. . In particular, a voice uttered from a human or a speech synthesizer as a language means is referred to as “voice sound”. Both the audio signal and the audio data express a sound in which a voice sound and a background sound are synthesized. Note that “audio signal” and “audio data” may be read as “audio signal” and “audio data”, respectively. Further, “video signal” and “video data” may be read as “video signal” and “video data”, respectively.
“Subtitle character information” refers to character information that is intended to be reproduced and displayed by a producer in principle in synchronization with an audio signal or a video signal, such as the contents of dialogue or lyrics. These audio signals (audio data), video signals (video data), and subtitle character information have an inseparable relationship with respect to the contents (contents) expressed by each. In principle, these three parties are intended to be played back synchronously by the producer. The same applies to other embodiments described later.
First Embodiment A caption control device according to a first embodiment of the present invention is used by being connected to a video reproduction device that receives and reproduces broadcast video and audio and subtitle character information. As a specific example of the video playback device, in the first embodiment, for example, this is a television receiver. The caption character information is transmitted by being superimposed on the video signal, or transmitted as a sub-video and received by the television receiver.
FIG. 1 is a block diagram illustrating a schematic configuration of a caption control device according to the first embodiment. This apparatus includes an audio input terminal 11, a video input terminal 21, and a character information input terminal 27. These input terminals 11, 21, 27 are respectively connected to corresponding audio output terminals, video output terminals, and character information output terminals of the television receiver via cables or the like. When a television receiver receives a broadcast wave through an antenna or the like, the television receiver demodulates the received wave and outputs an audio signal, a video signal, and subtitle character information from the output terminals.
The subtitle control apparatus according to the present embodiment includes a voice quality analysis unit 12 that analyzes a voice signal input to the voice input terminal 11 and a microphone as components related to the main part, and detects ambient noise levels. A noise detection unit 14, a subtitle display control unit 23 that controls display of subtitle character information according to a rule, and character font data. The subtitle character information is input from the character information input terminal 27 and subtitles are generated using the character font data. A caption video generation unit 24 that generates a video signal of characters and synthesizes it with the video signal input from the video input terminal 21 to generate a video signal with captions is provided. The caption control device according to the present invention can be realized by, for example, computer software. In this case, the caption control program executes a procedure for causing the computer to function as a caption control device.
The subtitle control apparatus according to the present embodiment is generated by the subtitle video generation unit 24 and the audio output terminal 13 that outputs the audio signal input to the audio quality analysis unit 12 as components related to the output of the subtitled video and audio. And a video output terminal 25 for outputting the subtitled video signal in synchronization with the audio signal. Note that the audio output terminal 13 is not indispensable because audio can be reproduced from the television receiver. However, for example, a monitor headphone or other audio reproduction device is connected to the audio output terminal 13. be able to. Further, the audio output terminal 13 may be provided by branching from the audio input terminal 11 before being input to the audio quality analysis unit 12. The output from the video output terminal 25 can be connected to, for example, another display device for monitoring. Further, the output from the video output terminal 25 can be input so as to be returned to the video input terminal of the television receiver. Of course, both the output from the audio output terminal 13 and the video output terminal 25 may be given to the other display device for monitoring and the audio input terminal and video input terminal of the television receiver, respectively.
Further, instead of the character information input terminal 27, the character information is superimposed on the video signal input to the video input terminal 21, and the superimposed character information is extracted in the caption video generation unit 24 and the captioned video signal is output. You may make it produce | generate.
Furthermore, instead of the caption video generation unit 24, a caption signal processing unit 39 is provided, and character information is superimposed on the video signal output from the video output terminal 25, and in accordance with control from the caption display control unit 23, Only the presence / absence of superimposition of character information may be switched, or the subtitle character information processed with the control information may be superimposed again on the video signal and output. In this case, the display device connected to the video output terminal 25 is intended to extract character information superimposed on the video signal and generate a video signal with captions (FIG. 16).
Further, the video output terminal 25 may be separately provided with the character information display section 68 or the character information output terminal 29 so as not to include character information (FIG. 17).
For these, a configuration suitable for input / output terminals of devices connected before and after the caption control device of the present embodiment may be selected.
In the analysis, the voice quality analysis unit 12 estimates a background sound level and a speech speed included in the input voice signal. The background sound includes background noise and background musical sound, and the level thereof can be estimated by using a method described in, for example, Japanese Patent Application Laid-Open Nos. 7-306695 and 5-113797. Further, the speech speed can be estimated by using a method described in, for example, Japanese Patent Laid-Open No. 5-28991. The voice quality analysis unit 12 outputs the background sound level and the speech speed estimated in this way as two analysis values used for the test of difficulty in hearing the voice sound included in the input voice signal.
The noise detector 14 captures sound with a microphone installed in the viewing environment and detects the noise level around the viewer. The microphone is preferably arranged at a position that is not easily affected by the sound output from the speaker of the television receiver (or the speaker of another sound reproduction device connected to the sound output terminal 13). At this time, referring to the audio signal input from the audio input terminal 11 and estimating surrounding sounds other than the reproduced sound based on the audio signal is preferable because noise detection accuracy can be improved.
The subtitle display control unit 23 includes a rule set used to test the difficulty of hearing a voice sound. The subtitle display control unit 23 determines the analysis value obtained by the voice quality analysis unit 12 and the ambient noise level detected by the noise detection unit 14. This rule set is applied to test the difficulty of hearing the voice included in the input voice signal. From the result of this test, the caption display control unit 23 determines the display mode of the caption character information and controls the caption video generation unit 24.
As shown in FIG. 2, in the present embodiment, the rule set represents the difficulty of hearing a voice by using three kinds of test reference values including background sound, ambient noise, and speech rate. Consists of. In the verification, whether the analysis value obtained by the voice quality analysis unit 12 and the ambient noise level detected by the noise detection unit 14 correspond to at least one of the rules 1 to 4 is checked against the verification reference value. Inspect. If none of the rules 1 to 4 is satisfied, the difficulty in hearing the voice is denied. In other words, it is not difficult to hear a voice, and caption control is not performed. Normally, captions are not displayed.
The interpretation of rule 1 to rule 4 included in the rule set is as follows.
Rule 1: When the background sound level (including background noise and background music) included in the audio signal is equal to or higher than a certain reference value, the caption is displayed.
Rule 2: A reference value that varies according to the ambient noise level is determined. When the background sound level included in the audio signal is equal to or greater than the fluctuation reference value, the subtitle is displayed. Rule 2 differs from rule 1 in that the reference value is not constant but variable.
Rule 3: When the ambient noise level is above a certain reference value, the subtitle is displayed.
Rule 4: When the utterance speed of the voice included in the audio signal is not within a certain reference range, the subtitle is displayed.
According to rule 1 and rule 2, when it is difficult to hear the voice due to the background sound included in the audio signal, according to rule 3, the relationship between the surrounding noise (eg, when a ringing tone is heard during viewing) When it is difficult to hear the voice and in accordance with rule 4, it is difficult to hear the voice due to the speaking speed (eg, when the speaking speed (speaking speed) of the speaker in the viewing voice is too fast or too slow), In each case, the subtitle video is output and displayed in synchronization with the audio. Therefore, the viewer (user) is supported to listen to the voice by the subtitle display, and does not hinder the understanding of the spoken content.
The present embodiment can be modified as follows. For example, even if rules 2 and 3 are not used, that is, only rules 1 and 4 relating to the background sound and speech rate are used, the effect of subtitle display control can be obtained. It is good also as a structure which does not comprise the noise detection part 14. FIG.
Further, for example, even when only the background sound level (rule 1) or the speech rate (rule 4) is used, the effect of subtitle display control can be obtained. Only the analysis may be performed.
It is also preferable to express the difficulty of hearing a voice as a function of a plurality of parameters (factors), evaluate this, and perform subtitle control according to the evaluation result. For example, not only background sounds and speaking speed, but also parameters such as low voice, low inflection, international and mobile phone voices, high reverberation, the number of simultaneous speakers, foreign languages, dialects, and narration Considering the quality of the test can be improved.
The reference values and function parameters in each rule in the rule set may be set or adjusted to desired values by the viewing user. For example, an elderly user may set a lower utterance speed reference range than a younger user. It is also conceivable to set a lower reference value for the background sound according to the hearing ability. This embodiment is useful for a hearing-impaired user who needs more information supplementation with captions than a normal hearing user. A user who views using headphones or earphones may increase the reference value of ambient noise or reduce the influence of ambient noise on each fluctuation reference value.
The display form of the caption character information determined by the caption display control unit 23 is not limited to non-display or display as shown in FIG. For example, subtitles are set to the normal display state at normal times, and the size of the subtitle characters is set smaller than the standard, and the subtitle characters are changed to the standard size when the test result of voice sound difficulty is applicable to the rule. (Fig. 3 (b)), when the rule is not applicable, the subtitle character is set to the standard size, and when the rule is applicable, the size of the subtitle character is enlarged (Fig. 3 (c)), or when the rule is applicable The number of display lines of characters may be increased (FIG. 3D).
Further, each level constituting the rule set is evaluated by providing a stage at each level representing the difficulty of hearing the voice sound, for example, as shown in FIG. 4, according to the stage of the difficulty of hearing the voice sound (voice quality). You may change the display mode of a subtitle character. In this example, when it is evaluated that it is the most difficult to hear, the subtitle character is displayed in the maximum size.
Second Embodiment A caption control device according to a second embodiment of the present invention is incorporated in a video playback device that plays back a recording medium on which video and audio and caption character information are recorded. As a specific example of the video playback device, in the second embodiment, for example, this is a DVD player. Note that a video recording / reproducing apparatus such as a DVD recorder or a hard disk video recorder may be used instead of the video reproducing apparatus such as a DVD player.
FIG. 5 is a block diagram showing a schematic configuration of a DVD player in which the caption control device according to the second embodiment is incorporated. This DVD player includes a drive mechanism unit (not shown) that loads a recording medium 31 on which video and audio data and subtitle character information data is recorded and reads the data.
Also, an audio reproduction unit 33 that reads and reproduces audio data from the recording medium 31, a video reproduction unit 34 that reads and reproduces video data from the recording medium 31, and a subtitle reproduction that reads and reproduces subtitle character information from the recording medium 31. Unit 35, and a playback control unit 32 that controls playback of the audio data and video data by inputting a playback control signal representing an instruction given by the user regarding playback of the audio data and video data from an operation panel, a remote control device, or the like. It comprises. The reproduction control signal represents a reproduction state such as at least reproduction volume and reproduction speed.
The DVD player according to the present embodiment includes a sound quality analysis unit 12 that analyzes sound data reproduced by the sound reproduction unit 33 and a microphone as components related to subtitle display control, and noise that detects ambient noise levels. The detection unit 14, the subtitle display control unit 23 that controls the display of subtitle character information according to the rule, and the character font data, and the subtitle character information reproduced by the subtitle reproduction unit 35 is input and the subtitle is displayed using the character font data. A subtitle video generation unit 24 that generates video data of characters and synthesizes the video data with video data reproduced by the video reproduction unit 34 to generate a video signal with subtitles is provided.
Then, the DVD player of the present embodiment is generated by the audio output unit 63 that outputs the audio data input to the audio quality analysis unit 12 and the subtitle image generation unit 24 as the constituent elements related to the output of the subtitled video and audio. A video output unit 65 for outputting the subtitled video signal. For example, an audio device such as a speaker is connected to the audio output unit 63, and a display device that displays an image is connected to the video output unit 65. In addition, it is good also as an integral structure provided with these audio equipment and a display apparatus in the housing | casing of a DVD player.
The voice quality 12 is analyzed in the same manner as in the first embodiment. That is, the background sound level and speech speed included in the input sound data are estimated, and these are output as two analysis values used for testing the difficulty of hearing the sound included in the input sound data.
Similarly to the first embodiment, the noise detection unit 14 detects the noise level around the viewer by capturing sound with a microphone installed in the viewing environment. In addition, it is good also as a structure which does not comprise the noise detection part 14 from balance of product cost etc.
The subtitle display control unit 23 includes a rule set used for testing the difficulty of hearing a voice, and the analysis value obtained by the voice quality analysis unit 12 and the ambient noise level detected by the noise detection unit 14, In addition, this rule set is applied to the playback state represented by the playback control signal input to the playback control unit 32 to test the difficulty of hearing the voice sound included in the input voice data. From the result of this test, the caption display control unit 23 determines the display mode of the caption character information and controls the caption video generation unit 24.
As shown in FIG. 6, in this embodiment, the rule set represents the difficulty of hearing a voice by using five kinds of test reference values including background sound, ambient noise, reproduction volume, speech rate, and reproduction rate. Yes, consisting of Rules 1 through 15. In the test, the analysis value obtained by the voice quality analysis unit 12, the ambient noise level detected by the noise detection unit 14, and the reproduction state represented by the reproduction control signal input to the reproduction control unit 32 are at least rule 1. Thru / or rule 15 is checked against the test reference value. If none of the rules 1 to 15 is satisfied, the difficulty in hearing the voice is denied. In other words, it is not difficult to hear a voice, and caption control is not performed. Normally, captions are not displayed.
Rule 1: When the background sound level (including background noise and background music) included in the audio data is equal to or higher than a certain reference value, the subtitle is displayed.
Rule 2: A reference value that varies according to the ambient noise level is determined. When the background sound level included in the audio data is equal to or greater than the fluctuation reference value, the subtitle is displayed. Rule 2 differs from rule 1 in that the reference value is not constant but variable.
Rule 4: When the utterance speed of the voice sound included in the audio data is not within a certain reference range, the subtitle is displayed.
Rule 5: A reference value that fluctuates in accordance with the reproduction volume in a state where audio data is being reproduced is determined. When the background sound level included in the audio data is equal to or greater than the fluctuation reference value, the caption is displayed.
Rule 6: A reference value that fluctuates in accordance with the reproduction volume and the ambient noise level when audio data is being reproduced is determined. When the background sound level included in the audio data is equal to or greater than the fluctuation reference value, the caption is displayed.
Rule 7: A reference value that varies according to the background sound level included in the audio data is determined. When the reproduction volume in the state where the audio data is being reproduced is equal to or less than the fluctuation reference value, the subtitle is displayed.
Rule 8: A reference value that varies according to the background sound level and the ambient noise level included in the audio data is determined. When the reproduction volume in the state where the audio data is being reproduced is equal to or less than the fluctuation reference value, the subtitle is displayed.
Rule 9: A reference range that varies according to the playback speed in the state in which audio data is being played back is determined. When the utterance speed of the voice sound included in the audio data is not within the fluctuation reference range, the subtitle is displayed.
Rule 10: A reference range that varies according to the utterance speed of the voice included in the voice data is determined. When the reproduction speed in the state where the audio data is being reproduced is not within the fluctuation reference range, the subtitle is displayed.
Rule 11: When the playback speed in the state where the audio data is being played is not within a certain reference range, the subtitle is displayed.
Rule 12: When the playback state is reverse playback (Reverse), the subtitle is displayed.
Rule 13: When the playback state is paused (Pause), the subtitle is displayed.
Rule 14: When the playback volume is muted (silenced) or below a certain reference value, the subtitle is displayed.
Rule 15: A reference value that varies depending on the ambient noise level is determined. When the playback volume is below the fluctuation reference value, the subtitle is displayed.
According to rule 1, rule 2, rule 5 and rule 6, subtitles are displayed when it is difficult to hear the voice due to the background sound included in the voice data, and according to rule 3, the voice is difficult to hear due to the surrounding noise. Sometimes subtitles are displayed, and according to rules 7, 8, 8, and 15, subtitles are displayed when it is difficult to hear the voice due to the playback volume. According to rules 4 and 9, the subtitles are Subtitles are displayed when it is difficult to hear voices, and according to Rules 10 to 13, subtitles are displayed when it is difficult to hear voices due to playback speed. Note that when rules 2, 3, 3, 6, 8, and 15 with ambient noise levels as test reference values are not used, that is, rules with background sound, playback speed, speech rate, and playback speed as test reference values. 1. Even when only rule 1, rule 5, rule 7, rule 9 to 14 are used, the effect of subtitle display control can be obtained, so that the configuration does not include the noise detection unit 14 in view of product cost and the like It is good.
Next, the flow of processing in the caption display control unit 23 will be described with reference to the flowchart of FIG.
First, a test is performed by applying (Rule 1, Rule 2, Rule 5, Rule 6) to the background sound level obtained as an analysis value by the voice quality analysis unit 12 (step S101). Next, verification is performed by applying (Rule 3) to the ambient noise level detected by the noise detection unit 14 (step S102). Next, a test is performed by applying (Rule 4 and Rule 9) to the speech rate obtained as an analysis value by the voice quality analysis unit 12 (Step S103). Next, the test is performed by applying (Rule 7, Rule 8, Rule 14, Rule 15) to the reproduction volume represented by the reproduction control signal from the reproduction control unit 32 (step S104). Next, a test is performed by applying (Rule 10 to Rule 13) to the reproduction speed represented by the reproduction control signal from the reproduction control unit 32 (Step S105). Finally, the display mode of the caption is determined based on the test results of the above steps, and the caption video generation unit 24 is controlled (step S106).
Here, the above-described step S101 is taken as an example, and the detailed processing flow will be described with reference to the flowchart of FIG.
First, the background sound level Ab included in the audio data is compared with a predetermined reference value Ab0 (step S111). When Ab is large, subtitle operation mode 1 is set according to rule 1 (step S191). Next, a reference value Fbn (An) that varies according to the ambient noise level An is calculated (step S120). This reference value Fbn (An) is compared with the background sound level Ab (step S121), and when Ab is large, subtitle operation mode 1 is set according to rule 2 (step S191). Next, a reference value Fbv (Av) that varies according to the reproduction volume Av is calculated (step S150). This reference value Fbv (Av) is compared with the background sound level Ab (step S151), and when Ab is large, subtitle operation mode 1 is set according to rule 5 (step S191). Next, a reference value Fbnv (An, Av) that varies according to the ambient noise level An and the reproduction volume Av is calculated (step S160). This reference value Fbnv (An, Av) is compared with the background sound level Ab (step S161), and when Ab is large, subtitle operation mode 1 is set according to rule 6 (step S191). Finally, if none of the conditions is met, the subtitle operation mode 0 is set (step S190).
(Third Embodiment) A caption control device according to a third embodiment of the present invention is used by being connected to a video playback device that plays back a recording medium on which video and audio and caption character information are recorded. As a specific example of the video playback apparatus, in the third embodiment, for example, this is a DVD player. Note that a video recording / reproducing apparatus such as a DVD recorder or a hard disk video recorder may be used instead of the video reproducing apparatus such as a DVD player.
FIG. 9 is a block diagram illustrating a schematic configuration of a caption control device according to the third embodiment. This apparatus comprises an audio input terminal 11, a video input terminal 21, a control information input terminal 26, and a character information input terminal 27. These input terminals are respectively an audio output terminal and a video output corresponding to the DVD player. It is connected to a terminal, a control information output terminal, and a character information output terminal via a cable or the like. When a user performs a playback operation on the DVD player through an operation panel, a remote control device, or the like, audio data, video data, and subtitle character information data are read and played from a recording medium attached to the player. The reproduced data is input to the audio input terminal 11, the video input terminal 21, and the character information input terminal 27 of the caption control device. Control information given by the user through operations on the operation panel, remote control device, etc. during reproduction is input to the control information input terminal 26. This control information represents various control information related to reproduction such as reproduction volume and reproduction speed, and is not limited to specific information. Further, the control information may be information representing the user's reproduction operation or information representing the operation state of the DVD player according to the reproduction operation.
The subtitle control apparatus according to the present embodiment includes a voice quality analysis unit 12 that analyzes voice data input to the voice input terminal 11 and a microphone as components related to the main part, and detects ambient noise levels. A noise detection unit 14, a subtitle display control unit 23 that controls display of subtitle character information according to a rule, and character font data. The subtitle character information is input from the character information input terminal 27 and subtitles are generated using the character font data. A subtitle video generating unit 24 that generates video data of characters and generates video signals with subtitles by synthesizing the video data input from the video input terminal 21;
The subtitle control apparatus according to this embodiment is generated by the subtitle video generation unit 24 and the audio output terminal 13 that outputs the audio data input to the audio quality analysis unit 12 as components related to the output of the subtitled video and audio. A video output terminal 25 for outputting the subtitled video data. The audio output terminal 13 is connected to a speaker, and the video output terminal 25 is connected to a display device. In place of the character information input terminal 27, the character information is superimposed on the video signal for transmitting the video data input to the video input terminal 21, and the superimposed character information is extracted by the caption video generation unit 24 and the caption is displayed. An attached video signal may be generated.
Furthermore, instead of the caption video generation unit 24, a caption signal processing unit 39 is provided, and character information is superimposed on the video signal output from the video output terminal 25, and in accordance with control from the caption display control unit 23, Only the presence / absence of superimposition of character information may be switched, or the subtitle character information processed with the control information may be superimposed again on the video signal and output. In this case, the display device connected to the video output terminal 25 is intended to extract character information superimposed on the video signal and generate a video signal with captions (FIG. 18).
Further, the video output terminal 25 may be separately provided with a character information output terminal 29 so as not to include character information (FIG. 19).
These may be selected in accordance with the specifications of the input / output terminals of the devices connected before and after the caption control device of the present embodiment.
Note that the caption control device of this embodiment can also be configured by a personal computer (PC).
The voice quality 12 is analyzed in the same manner as in the first embodiment. That is, the background sound level and speech speed included in the input sound data are estimated, and these are output as two analysis values for determining the difficulty of hearing the sound included in the input sound data. Similarly to the first embodiment, the noise detection unit 14 detects the noise level around the viewer by capturing sound with a microphone installed in the viewing environment. In addition, it is good also as a structure which does not comprise the noise detection part 14 from balance of product cost etc.
The subtitle display control unit 23 includes the same rule set (see FIG. 6) as that of the second embodiment, and the analysis value obtained by the voice quality analysis unit 12 and the surroundings detected by the noise detection unit 14. This rule set is applied to the noise level and the reproduction state represented by the reproduction control signal input to the control information input terminal 26 to test the difficulty of hearing the voice sound included in the input voice data. From the result of this test, the caption display control unit 23 determines the display mode of the caption character information and controls the caption video generation unit 24. In the verification, at least the rule is set to the analysis value obtained by the voice quality analysis unit 12, the ambient noise level detected by the noise detection unit 14, and the reproduction state represented by the reproduction control signal input to the control information input terminal 26. It is checked against one of the rules 1 to 15 against the test reference value.
(Fourth Embodiment) A caption control device according to a fourth embodiment of the present invention is used by being connected to an audio reproduction device that reproduces a recording medium on which audio and subtitle character information is recorded. As a specific example of the audio reproducing device, in the fourth embodiment, for example, this is an MD (Mini Disc) player. A CD (Compact Disc) player may be used instead of the MD player. Further, instead of these sound reproducing devices, a sound recording / reproducing device having a recording function such as an MD recorder or an IC memory recorder may be used.
FIG. 10 is a block diagram illustrating a schematic configuration of a caption control device according to the fourth embodiment. This apparatus includes a voice input terminal 11, a control information input terminal 26, and a character information input terminal 27. These input terminals respectively correspond to a voice output terminal, a control information output terminal, and character information corresponding to the MD player. It is connected to the output terminal via a cable or the like. When a user performs a reproduction operation on the MD player through an operation panel, a remote controller, or the like, audio data and subtitle character information data are read from a recording medium attached to the player and reproduced. The reproduced data is input to the audio input terminal 11 and the character information input terminal 27 of the caption control device. Control information given by the user through operations on the operation panel, remote control device, etc. during reproduction is input to the control information input terminal 26. This control information represents various control information related to reproduction such as reproduction volume and reproduction speed, and is not limited to specific information.
The subtitle control apparatus according to the present embodiment includes a voice quality analysis unit 12 that analyzes voice data input to the voice input terminal 11 and a microphone as components related to the main part, and detects ambient noise levels. The noise detection part 14 and the caption display control part 23 which controls a display of caption character information according to a rule are comprised.
The subtitle control apparatus according to the present embodiment displays the character information display that displays the subtitle character information input from the character information input terminal 27 under the control of the subtitle display control unit 23 as a component related to the output of the audio and the subtitle. Unit 68 and an audio output terminal 13 for outputting the audio data input to the audio quality analysis unit 12. The audio output terminal 13 is connected to a speaker or the like. The character information display unit 68 is composed of, for example, a liquid crystal display device.
The voice quality 12 is analyzed in the same manner as in the first embodiment. That is, the background sound level and speech speed included in the input sound data are estimated, and these are output as two analysis values used for testing the difficulty of hearing the sound included in the input sound data. Similarly to the first embodiment, the noise detection unit 14 detects the noise level around the viewer by capturing sound with a microphone installed in the viewing environment. In addition, it is good also as a structure which does not comprise the noise detection part 14 from balance of product cost etc.
The subtitle display control unit 23 includes the same rule set (see FIG. 6) as that of the second embodiment, and the analysis value obtained by the voice quality analysis unit 12 and the surroundings detected by the noise detection unit 14. This rule set is applied to the noise level and the reproduction state represented by the reproduction control signal input to the control information input terminal 26 to test the difficulty of hearing the voice sound included in the input voice data. From the result of this test, the subtitle display control unit 23 determines the display mode of the subtitle character information and controls the subtitle video generation unit 68. In the verification, at least the rule is set to the analysis value obtained by the voice quality analysis unit 12, the ambient noise level detected by the noise detection unit 14, and the reproduction state represented by the reproduction control signal input to the control information input terminal 26. It is checked against one of the rules 1 to 15 against the test reference value. Also, the caption control device of the present embodiment can be used by being connected to an audio reproduction device that receives and reproduces broadcast audio and caption character information. As a specific example of the sound reproducing device, for example, there is a radio broadcast receiver. In this case, the control information input terminal 26 may not be provided.
Fifth Embodiment A caption control device according to a fifth embodiment of the present invention is incorporated in a content player that receives and reproduces broadcasted video and audio and video content including subtitle character information.
FIG. 11 is a block diagram showing a schematic configuration of a content player in which the caption control device according to the fifth embodiment is incorporated. This content player can be composed of, for example, a personal computer (PC), and receives a video content transmitted via a computer network or the like, a content receiving unit 41, and audio data from the content received by the content receiving unit 41. An audio playback unit 43 that plays back separately, a video playback unit 44 that plays back video data separately from content received by the content receiving unit 41, and an instruction given by the user regarding playback of audio data and video data A reproduction control unit 42 that inputs a signal from an operation panel or a remote control device and controls reproduction of the audio data and video data, and a subtitle reproduction unit that separates and reproduces subtitle character information from the content received by the content reception unit 41 45.
In addition, the content player according to the present embodiment includes a sound quality analysis unit 12 that analyzes sound data reproduced by the sound reproduction unit 43 and a microphone as components related to subtitle display control, and detects ambient noise levels. A noise detection unit 14, a subtitle display control unit 23 that controls display of subtitle character information in accordance with the rules, and character font data. The subtitle character information reproduced by the subtitle reproduction unit 45 is input and the character font data is used. A subtitle video generation unit that generates video data with subtitles by generating video data of subtitle characters and combining it with video data reproduced by the video reproduction unit;
The content player according to the present embodiment includes, for example, a speaker as a component related to the output of video with subtitles and audio, and an audio output unit 63 that outputs audio based on audio data input to the audio quality analysis unit 12; For example, it includes a display device, and includes a video output unit 65 that outputs video based on video data with subtitles generated by the subtitle video generation unit 24.
The subtitle display control unit 23 includes the same rule set (see FIG. 6) as that of the second embodiment, and the analysis value obtained by the voice quality analysis unit 12 and the surroundings detected by the noise detection unit 14. This rule set is applied to the noise level and the reproduction state represented by the reproduction control signal input from the reproduction control unit 42 to test the difficulty of hearing the voice sound included in the input voice data. From the result of this test, the caption display control unit 23 determines the display mode of the caption character information and controls the caption video generation unit 24. In the verification, the analysis value obtained by the voice quality analysis unit 12, the ambient noise level detected by the noise detection unit 14, and the reproduction state represented by the reproduction control signal from the reproduction control unit 42 are at least rule 1 to rule. It is inspected against the test reference value to determine whether any of 15 is satisfied.
(Sixth Embodiment) A caption control device according to a sixth embodiment of the present invention is incorporated in a video reproduction device that receives and reproduces broadcast video and audio and subtitle character information. As a specific example of the video reproduction device, in the sixth embodiment, for example, this is a television receiver. The caption character information is transmitted by being superimposed on the video signal, or transmitted as a sub-video and received by the television receiver.
FIG. 12 is a block diagram illustrating a schematic configuration of a television receiver in which the caption control device according to the sixth embodiment is incorporated. The television receiver includes a broadcast receiving unit 51 that receives a broadcast signal transmitted via radio waves, cables, and the like, an audio demodulation unit 53 that demodulates an audio signal from the broadcast signal received by the broadcast receiving unit 51, and a broadcast A video demodulation unit 54 that demodulates a video signal from a broadcast signal received by the reception unit 51 and a caption demodulation unit 55 that demodulates caption character information from the broadcast signal received by the broadcast reception unit 51 are provided.
The television receiver according to the present embodiment includes a voice quality analysis unit 12 that analyzes a voice signal demodulated by the voice demodulation unit 53 and a microphone as components related to subtitle display control, and detects ambient noise levels. A subtitle display control section 23 for controlling display of subtitle character information according to a rule, character font data, subtitle character information demodulated by the subtitle demodulation section 55 is input and the character font data is used. And a caption video generation unit 24 that generates a video signal with captions by generating a video signal of subtitle characters and combining it with the video signal demodulated by the video demodulation unit 54.
In addition, the television receiver according to the present embodiment includes, for example, a speaker as a component related to audio and video output, and an audio output unit 63 that outputs audio based on the audio signal input to the audio quality analysis unit 12. It has. The video output unit 65 includes a liquid crystal display or a CRT type display device, and outputs a video based on the video signal with caption generated by the caption video generation unit 24.
The voice quality 12 is analyzed in the same manner as in the first embodiment. That is, the background sound level and speech speed included in the input sound signal are estimated, and these are output as two analysis values used for the test of difficulty in hearing the sound included in the input sound signal. Similarly to the first embodiment, the noise detection unit 14 detects the noise level around the viewer by capturing sound with a microphone installed in the viewing environment. In addition, it is good also as a structure which does not comprise the noise detection part 14 from balance of product cost etc.
The caption display control unit 23 has the same rule set (see FIG. 2) as that of the first embodiment, and the analysis value obtained by the voice quality analysis unit 12 and the surroundings detected by the noise detection unit 14 This rule set is applied to the noise level to test the difficulty of hearing the voice sound included in the input voice signal. From the result of this test, the caption display control unit 23 determines the display mode of the caption character information and controls the caption video generation unit 24. In the verification, whether the analysis value obtained by the voice quality analysis unit 12 and the ambient noise level detected by the noise detection unit 14 correspond to at least one of the rules 1 to 4 is compared with the verification reference value. inspect.
(Seventh Embodiment) A caption control device according to a seventh embodiment of the present invention is incorporated in an audio reproducing device that reproduces a recording medium on which audio and subtitle character information is recorded. As a specific example of the audio reproducing device, in the seventh embodiment, for example, this is an MD (Mini Disc) player. A CD (Compact Disc) player may be used instead of the MD player. Further, instead of these sound reproducing devices, a sound recording / reproducing device having a recording function such as an MD recorder or an IC memory recorder may be used.
FIG. 13 is a block diagram showing a schematic configuration of an MD player in which the caption control device according to the seventh embodiment is incorporated. This MD player includes a drive mechanism unit (not shown) that loads a recording medium 31 on which audio and caption character information data is recorded and reads the data.
Also, an audio reproduction unit 33 that reads out and reproduces audio data from the recording medium 31, a subtitle reproduction unit 35 that reads out and reproduces subtitle character information from the recording medium 31, and an instruction given by the user regarding the reproduction of audio data A reproduction control unit 32 is provided for inputting a reproduction control signal from an operation panel, a remote control device or the like and controlling reproduction of the audio data. The reproduction control signal represents a reproduction state such as at least reproduction volume and reproduction speed.
The MD player according to the present embodiment includes, as constituent elements related to subtitle display control, an audio quality analysis unit 12 that analyzes audio data reproduced by the audio reproduction unit 33, and a microphone that detects a surrounding noise level. It includes a detection unit 14 and a subtitle display control unit 23 that controls display of subtitle character information in accordance with a rule.
Then, the MD player according to the present embodiment displays the subtitle character information reproduced by the subtitle reproduction unit 35 under the control of the subtitle display control unit 23 as a component related to the output of the audio and subtitles. And an audio output unit 63 that outputs the audio data input to the audio quality analysis unit 12. The character information display unit 68 is composed of, for example, a liquid crystal display device. For example, an audio device such as a speaker is connected to the audio output unit 63. In addition, it is good also as an integral structure provided with this audio equipment in the housing | casing of MD player.
(Eighth Embodiment) A caption control device according to an eighth embodiment of the present invention is incorporated in a content player that receives and reproduces audio content including broadcast audio and subtitle character information.
FIG. 14 is a block diagram showing a schematic configuration of a content player in which the caption control device according to the eighth embodiment is incorporated. This content player can be constituted by, for example, a personal computer (PC), and receives a content receiver 41 that receives audio content transmitted via a computer network or the like, and audio data from the content received by the content receiver 41. An audio playback unit 43 that plays back separately, a playback control unit 42 that controls the playback of the audio data by inputting a signal representing an instruction given by the user from the operation panel or a remote control device, etc. The content receiving unit 41 includes a subtitle reproduction unit 45 that separates and reproduces subtitle character information from the received content.
The content player according to the present embodiment includes, as constituent elements related to subtitle display control, an audio quality analysis unit 12 that analyzes audio data reproduced by the audio reproduction unit 43, and a microphone that detects a surrounding noise level. It includes a detection unit 14 and a subtitle display control unit 23 that controls display of subtitle character information in accordance with a rule.
Then, the content player of the present embodiment displays the character information display unit 68 that displays the subtitle character information reproduced by the subtitle reproduction unit 45 under the control of the subtitle display control unit 23 as a component related to the output of audio and subtitles. And an audio output unit 63 that outputs the audio data input to the audio quality analysis unit 12. The character information display unit 68 is composed of, for example, a liquid crystal display device. For example, an audio device such as a speaker is connected to the audio output unit 63. In addition, it is good also as an integral structure provided with this audio equipment in the housing | casing of a content player.
Ninth Embodiment A caption control device according to a ninth embodiment of the present invention is incorporated in an audio reproduction device that receives and reproduces broadcast audio and caption character information. As a specific example of the audio reproducing device, in the ninth embodiment, for example, this is a radio broadcast receiver compatible with FM character multiplex broadcasting. The subtitle character information is transmitted with being superimposed on the FM broadcast radio wave band together with the audio signal. Instead of the radio receiver, a terrestrial digital audio broadcast receiver may be used. The caption character information is transmitted as a data broadcast.
FIG. 15 is a block diagram showing a schematic configuration of a radio broadcast receiver in which the caption control device according to the ninth embodiment is incorporated. The radio broadcast receiver includes a broadcast receiving unit 51 that receives a broadcast signal transmitted via radio waves, cables, and the like, an audio demodulation unit 53 that demodulates an audio signal from the broadcast signal received by the broadcast receiving unit 51, and a broadcast A subtitle demodulation unit 55 that demodulates subtitle character information from the broadcast signal received by the reception unit 51;
The radio broadcast receiver according to the present embodiment includes a voice quality analysis unit 12 that analyzes a voice signal demodulated by the voice demodulation unit 53 and a microphone as components related to subtitle display control, and detects ambient noise levels. And a subtitle display control unit 23 that controls display of subtitle character information in accordance with the rules.
The radio broadcast receiver according to the present embodiment displays the character information display that displays the subtitle character information demodulated by the subtitle demodulation unit 55 under the control of the subtitle display control unit 23 as a component related to the output of the audio and the subtitle. And an audio output unit 63 that outputs the audio signal input to the audio quality analysis unit 12. The character information display unit 68 is composed of, for example, a liquid crystal display device. For example, an audio device such as a speaker is connected to the audio output unit 63. In addition, it is good also as an integral structure provided with this audio equipment in the housing | casing of a radio broadcast receiver.
As described above, according to the present invention, supplemental subtitle character information is displayed so that the content of the voice can be properly and reliably transmitted to the viewer even in a situation where it is difficult to hear the voice in voice output, or the subtitle is displayed. A subtitle control apparatus, method, and program for controlling the display form of character information can be provided.
FIG. 1 is a block diagram showing a schematic configuration of a caption control device according to a first embodiment of the present invention.
FIG. 2 is a diagram illustrating an example of a rule set provided in the caption display control unit according to the first embodiment.
FIG. 3 is a diagram showing an example of subtitle display control in the first embodiment.
FIG. 4 is a diagram showing another example of subtitle display control in the first embodiment.
FIG. 5 is a block diagram showing a schematic configuration of a video reproduction apparatus according to a second embodiment of the present invention.
FIG. 6 is a diagram illustrating an example of a rule set provided in the caption display control unit according to the second embodiment.
FIG. 7 is a flowchart showing a flow of processing in the caption display control unit of the second embodiment.
FIG. 8 is a flowchart showing a detailed processing flow in step S101 of FIG.
FIG. 9 is a block diagram showing a schematic configuration of a caption control device according to a third embodiment of the present invention.
FIG. 10 is a block diagram showing a schematic configuration of a caption control device according to a fourth embodiment of the present invention.
FIG. 11 is a block diagram showing a schematic configuration of a content player according to a fifth embodiment of the present invention.
FIG. 12 is a block diagram showing a schematic configuration of a video reproduction apparatus according to a sixth embodiment of the present invention.
FIG. 13 is a block diagram showing a schematic configuration of an audio reproduction device according to a seventh embodiment of the present invention.
FIG. 14 is a block diagram showing a schematic configuration of an audio reproduction device according to an eighth embodiment of the present invention.
FIG. 15 is a block diagram showing a schematic configuration of an audio reproduction device according to a ninth embodiment of the present invention.
FIG. 16 is a block diagram showing another schematic configuration of the caption control device according to the first embodiment of the present invention;
FIG. 17 is a block diagram showing another schematic configuration of the caption control device according to the first embodiment of the present invention;
FIG. 18 is a block diagram showing another schematic configuration of the caption control device according to the third embodiment of the present invention.
FIG. 19 is a block diagram showing another schematic configuration of the caption control device according to the third embodiment of the present invention.
DESCRIPTION OF SYMBOLS 11 ... Voice input terminal, 12 ... Voice quality analysis part, 13 ... Voice output terminal, 14 ... Noise detection part, 21 ... Video input terminal, 23 ... Subtitle display control part, 24 ... Subtitle video generation part, 25 ... Video output terminal 27 ... Character information input terminal, 29 ... Character information output terminal, 31 ... Storage medium, 32 ... Playback control section, 33 ... Audio playback section, 34 ... Video playback section, 35 ... Subtitle playback section, 39 ... Subtitle signal processing section , 41 ... content receiver, 42 ... playback controller, 43 ... audio player, 44 ... video player, 45 ... subtitle player, 51 ... broadcast receiver, 53 ... audio demodulator, 54 ... video demodulator, 55 ... Subtitle demodulation unit, 63 ... Audio output unit, 65 ... Video output unit, 68 ... Text information display unit
In a caption display control device that controls a display mode of captions corresponding to an audio signal in which a voice sound and a background sound or a background musical sound are synthesized ,
Analyzing means for analyzing the audio signal to obtain a plurality of analysis values including at least a background sound level of the background sound or background music ;
A test means for testing the difficulty of hearing a voice by comparing the plurality of analysis values with a plurality of reference values including at least a reference value of a background sound level;
A subtitle display control device comprising: means for determining the display mode according to the result of the test.
2. The caption display control device according to claim 1, wherein the verification unit uses a reference value range of an utterance speed capable of determining whether or not a voice sound is difficult to hear for verification.
3. The caption according to claim 1, further comprising noise detecting means for detecting a surrounding noise level, wherein the verification means uses a reference value of the ambient noise level for determining whether or not the voice sound is difficult to hear for verification. Display control device.
Control signal input means for inputting a playback control signal representing the playback volume or playback speed of the audio signal, and the verification means is a reference value of playback volume or playback speed that can determine whether or not the voice sound is difficult to hear. 4. The caption display control device according to claim 1, wherein the reference value range is used for the test.
5. The caption display according to claim 1, wherein the determination unit switches the display mode of the caption from non-display to display when a test result indicating that it is difficult to hear a voice sound included in the audio signal is obtained. Control device.
6. The caption display control device according to claim 1, wherein the determination unit enlarges the character size of the caption when a test result indicating that it is difficult to hear a voice sound included in the audio signal is obtained.
The caption display control device according to claim 1, wherein the determination unit expands the number of character lines of the caption when obtaining a test result indicating that it is difficult to hear a voice sound included in the audio signal.
In a subtitle display control method for controlling a display mode of subtitles corresponding to an audio signal in which a voice sound and a background sound or background music are synthesized ,
Analyzing the audio signal to obtain a plurality of analysis values including at least a background sound level for the background sound or background music ; and
Comparing the plurality of analysis values with a plurality of reference values including at least a reference value of a background sound level;
A subtitle display control method comprising: determining the display mode according to a result of the test.
In a subtitle display control program for controlling a display mode of subtitles corresponding to an audio signal in which a voice sound and a background sound or background music are synthesized ,
An analysis procedure for analyzing the audio signal to obtain a plurality of analysis values including at least a background sound level of the background sound or background music ;
A procedure for testing the difficulty of hearing a voice by comparing the plurality of analysis values with a plurality of reference values including at least a reference value of a background sound level;
A subtitle display control program for causing a computer to execute a procedure for determining the display mode according to the result of the test.
JP2003207621A 2003-08-15 2003-08-15 Subtitle control apparatus and method, and program Expired - Fee Related JP4128916B2 (en)
JP2003207621A JP4128916B2 (en) 2003-08-15 2003-08-15 Subtitle control apparatus and method, and program
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JP2005064599A JP2005064599A (en) 2005-03-10
JP4128916B2 true JP4128916B2 (en) 2008-07-30
ID=34131440
JP2003207621A Expired - Fee Related JP4128916B2 (en) 2003-08-15 2003-08-15 Subtitle control apparatus and method, and program
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