阅读说明：本技术 照明设备 (Lighting device ) 是由 P·J·福尔曼 P·戴克斯勒 于 2020-05-04 设计创作，主要内容包括：本发明提供了一种用于确定和传送音频信号的清晰度的照明设备,其中音频信号包括重复音频特征的多次出现,其中重复音频特征的每次出现包括声学特性的相应值,其中该照明设备包括：光源；麦克风,用于检测音频信号；处理器,被配置为：从麦克风接收音频信号,基于所述音频信号确定基线值,如果重复音频特征的最后一次出现包括至少等于基线值的声学特性的相应值,则确定音频信号的正清晰度,或者如果重复音频特征的最后一次出现包括小于基线值的声学特性的相应值,则确定音频信号的负清晰度,以及控制光源经由照明特性来传送音频信号的确定的正和/或负清晰度。(The invention provides a lighting device for determining and communicating the intelligibility of an audio signal, wherein the audio signal comprises a plurality of occurrences of a repeating audio feature, wherein each occurrence of the repeating audio feature comprises a respective value of an acoustic characteristic, wherein the lighting device comprises: a light source; a microphone for detecting an audio signal; a processor configured to: receiving an audio signal from a microphone, determining a baseline value based on the audio signal, determining a positive sharpness of the audio signal if the last occurrence of a repeating audio feature comprises a respective value of the acoustic characteristic at least equal to the baseline value, or determining a negative sharpness of the audio signal if the last occurrence of a repeating audio feature comprises a respective value of the acoustic characteristic less than the baseline value, and controlling a light source to transmit the determined positive and/or negative sharpness of the audio signal via the lighting characteristic.)

1. A lighting device for determining and communicating the intelligibility of an audio signal, wherein the audio signal comprises a plurality of occurrences of a repeating audio feature, wherein each occurrence of the repeating audio feature comprises a respective value of an acoustic characteristic, wherein the lighting device comprises:

-a light source;

-a microphone for detecting the audio signal;

-a processor configured to:

receiving the audio signal from the microphone and,

determining a baseline value based on the audio signal,

determining a positive clarity of the audio signal if a last occurrence of the repeating audio feature comprises a respective value of the acoustic characteristic at least equal to the baseline value, or

Determining a negative clarity of the audio signal if a last occurrence of the repeating audio feature comprises a corresponding value of the acoustic characteristic that is less than the baseline value, an

Controlling the light source to communicate the determined positive and/or negative clarity of the audio signal via a lighting characteristic.

2. The lighting device of claim 1, wherein the processor is configured to determine a respective value of an acoustic characteristic of a first occurrence of the repeating audio feature as the baseline value.

3. The lighting device of claim 1, wherein the processor is configured to determine an average of respective values of the acoustic characteristic for each occurrence of the repeating audio feature as the baseline value.

4. The lighting device of claim 1, wherein the audio signal further comprises a trigger feature that activates the audio signal, wherein the trigger feature comprises a value of the acoustic characteristic;

wherein the processor is configured to determine a value of an acoustic characteristic of the trigger feature as the baseline value.

5. The lighting device according to any one of the preceding claims, wherein the acoustic characteristic is one of: sound pressure level, frequency, or timbre.

6. The lighting device according to any one of the preceding claims, wherein the lighting characteristic is light modulation, hue, color temperature, directionality, and/or light intensity.

7. The illumination apparatus of claim 6, wherein the light modulation comprises Li-Fi or visible light communication.

8. The lighting device according to any one of the preceding claims, wherein the light source is a directional light source.

9. The lighting device of claim 8, wherein the processor is configured to:

obtaining a direction of origin of the audio signal relative to the lighting device, an

Controlling the directional light source to communicate the determined positive and/or negative clarity of the audio signal via the lighting characteristic in the direction.

10. The lighting device as set forth in claim 9,

wherein the processor is configured to obtain the direction from a lighting system comprising an array of microphones, or

Wherein the microphone is a directional microphone and the processor is configured to obtain the direction from the directional microphone.

11. A lighting device according to any one of the preceding claims, wherein the lighting device comprises a further light source, wherein the further light source is arranged to provide ambient lighting.

12. The lighting device of claim 11, wherein the processor is configured to: controlling the further light source to transmit at least a portion of the audio signal via a Li-Fi signal or a VLC signal if the processor determines a negative clarity of the audio signal.

13. The lighting device according to any one of the preceding claims, wherein the lighting device comprises a speaker, wherein the processor is configured to: controlling the speaker to transmit at least a portion of the audio signal if the processor determines a negative intelligibility of the audio signal.

14. A system for determining and communicating the intelligibility of an audio signal, wherein the system comprises at least two lighting devices according to any one of the preceding claims 1 to 13.

15. A method of determining and conveying intelligibility of an audio signal, wherein the audio signal comprises a plurality of occurrences of a repeating audio feature, wherein each occurrence of the repeating audio feature comprises a respective value of an acoustic characteristic, wherein the method comprises:

-detecting the audio signal;

-determining a baseline value based on the audio signal;

-determining a positive clarity of the audio signal if the last occurrence of the repeating audio feature comprises a respective value of the acoustic characteristic at least equal to the baseline value, or

-determining a negative clarity of the audio signal if the last occurrence of the repeating audio feature comprises a corresponding value of the acoustic property that is smaller than the baseline value, and

-controlling a light source to communicate the determined positive and/or negative sharpness of the audio signal via a lighting characteristic.

Technical Field

The invention relates to a lighting device for determining and transmitting the intelligibility of an audio signal, wherein the lighting device comprises a light source, a microphone and a processor. The invention also relates to a system for determining and transmitting the intelligibility of an audio signal, wherein the system comprises at least two lighting devices according to the invention. The invention also relates to a method of determining and communicating the intelligibility of an audio signal, and to a computer program product. The invention also relates to an actuator device, mutatis mutandis.

Background

Open office work is popular in businesses. Acoustic comfort and/or acoustic clarity are associated with commercial environments. Acoustic comfort may, for example, enhance human productivity and satisfaction, while clear speech may, for example, improve the effectiveness of communication and expression. Similar observations may be found in entertainment environments such as, for example, professional arenas, stadiums, or theaters. In contrast, in some instances within a business environment, it may be desirable for the speech to be private and unclear.

Thus, real-time feedback on acoustic propagation in space may be a goal in order to obtain insight into acoustic comfort and/or acoustic clarity of sound (originating from a sound source).

For example: it is known to provide means for visualizing the Sound Pressure Level (SPL) in a space, for example by means of a decibel meter (e.g. in a discotheque). Furthermore, a noise level alerting the user to them is found in WO2019/002327a 1. Further, US2016/0163302a1 discloses a sound attenuating panel having light sources embedded therein, which may be controlled based on increasing and/or decreasing noise levels. In addition, WO2018/210588a1 discloses establishing a propagation map of sound data obtained from sound sensors comprised by a lighting network.

Although the examples may disclose detecting noise levels and providing feedback, for example by using a lighting infrastructure, none of the above may detect the intelligibility of the sound signal itself. While it is known to provide intelligent assistants based on voice control (which can implement semantic analysis on detected voice commands), such as Amazon Alexa or Google Echo, such assistants still disadvantageously require high processing power and/or a back-end that is preferred for computation.

Disclosure of Invention

It is an object of the present invention to provide an improved lighting device for determining and transmitting the intelligibility of an audio signal, which at least alleviates the above-mentioned problems and disadvantages. To this end, the invention provides a lighting device for determining and communicating the intelligibility of an audio signal, wherein the audio signal comprises a plurality of occurrences of a repeating audio feature, wherein each occurrence of the repeating audio feature comprises a respective value of an acoustic characteristic, wherein the lighting device comprises: a light source; a microphone for detecting an audio signal; a processor configured to: receiving an audio signal from a microphone, determining a baseline value based on the audio signal, determining a positive sharpness of the audio signal if the last occurrence of a repeating audio feature comprises a respective value of the acoustic characteristic at least equal to the baseline value, or determining a negative sharpness of the audio signal if the last occurrence of a repeating audio feature comprises a respective value of the acoustic characteristic less than the baseline value, and controlling a light source to transmit the determined positive and/or negative sharpness of the audio signal via the lighting characteristic.

The audio signal comprises a plurality of occurrences of a repeating audio feature. The audio signal may be, for example, human speech or an audio (i.e., sound) segment of human speech. The audio signal may for example originate from a person present in the space. Thus, the repeating audio feature may be, for example, a characteristic sound, a vowel, an article, a word, a phrase, or a sentence; which may be repeated throughout the duration of the audio signal. Furthermore, each occurrence of a repeating audio feature in the audio signal may comprise a respective value of the acoustic characteristic. In an embodiment, the acoustic characteristic may be one of: sound Pressure Level (SPL), frequency, or timbre, or rhythm. These acoustic properties are common in the acoustic field.

Thus, the audio signal may comprise repeating audio features, wherein each individual occurrence of a repeating feature over time comprises its respective value of said acoustic characteristic. Thus, the lighting device according to the invention may utilize this insight to determine the intelligibility (i.e. positive intelligibility or negative intelligibility) of the audio signal and subsequently transmit the determined intelligibility in order to provide feedback on said intelligibility of the audio signal. Thus, the processor is configured to determine the intelligibility of the audio signal by comparing the respective value of the last occurrence of the repeating audio feature with the baseline value.

Thus, since the lighting device according to the invention does not require interpretation of the meaning of repetitive audio features and/or does not require performing semantic analysis on the intelligibility, the invention advantageously provides a more computationally and/or power efficient means for determining and transmitting intelligibility of an audio signal.

Thus, due to the limited processing power required, the ability to determine the intelligibility of an audio signal can advantageously be achieved for conventional lighting devices having sensing capabilities, thereby providing an improved lighting device according to the invention. Such a lighting device may for example be an outdoor lighting device, an indoor lighting device, a luminaire, a light pole, a spotlight, an LED strip, a TLED, a pixelated LED spotlight, or a wall washer.

More specifically: the lighting device according to the invention comprises a light source, a microphone and a processor. The microphone is arranged to detect an audio signal and to provide the detected (or: measured) audio signal to the processor. A processor receives the audio signal from the microphone and performs processing steps thereon. Alternatively, the lighting device may be a connected lighting device with wireless connectivity. Wireless connectivity may enable the lighting device to communicate with other lighting devices according to the present invention, and/or with other connected devices, such as devices in a wireless network.

Thus, the processor (in cooperation with the microphone) may keep track of (or: listen for) each occurrence of each repeating feature in the audio signal. Thus, the processor may distinguish between sound sources using techniques well known in the acoustic arts. In some examples, the processor may be configured (or: programmed, or: initialized by the network entry) to keep track of (or: listen for) each occurrence of a limited set of repeating features in the audio signal. Such a limited set of repeating features, e.g. only vowels or articles (in syntax), may be predefined during installation or network initialization of the lighting device.

Further, as mentioned in part, the processor is further configured to determine a baseline value based on the audio signal. In an embodiment, the processor may be configured to determine the baseline value based on at least a first occurrence of a repeating audio feature in the audio signal. Thus, the baseline value may be used as a reference value for determining the intelligibility of the audio signal. For example, in an initial example, the baseline value may be predefined, such as a predefined threshold. The lighting device may be initialized for network entry with such a predefined threshold, wherein the processor may be configured to receive a network entry initialization command comprising said predefined threshold.

More detailed description of the predefined baseline value will be provided below. For example, the baseline value may be determined based on sensor input and/or user input. The sensor input may be, for example, detected activity, gestures, and/or person density. The user input may be, for example, age or identity.

As mentioned, the lighting device according to the invention determines the intelligibility of the audio signal and subsequently transmits the determined intelligibility in order to provide feedback on said intelligibility of the audio signal. Thus, the processor is configured to determine the intelligibility of the audio signal by comparing the respective value of the last occurrence of the repeating audio feature with the baseline value. Namely:

the processor is configured to determine a positive intelligibility of the audio signal if the last occurrence of the repeating audio feature comprises a corresponding value of the acoustic characteristic at least equal to the baseline value. Thus, the audio signal is clear because the corresponding value of the acoustic characteristic of the last occurrence of the repeating feature exceeds at least the threshold set by the baseline value.

For example, recited in a personJohn McCraePoem ofIn Flanders FieldsIn this case, the last occurrence of the article "the" may include a sound pressure level of 50 dB, and the baseline value may be predetermined to be 45 dB, which provides a conclusion that the poem (at that point or the occurrence of the article "the") is clear (i.e., positive clarity). The light source is thus controlled accordingly.

Conversely, if the last occurrence of the repeating audio feature includes a corresponding value of the acoustic characteristic that is less than the baseline value, the processor is configured to determine a negative clarity of the audio signal. Thus, the audio signal is not clear because the corresponding value of the last occurring acoustic characteristic of the repeating feature does not at least exceed the threshold set by the baseline value.

For example, recited in a personJohn McCraePoem ofIn Flanders FieldsIn this case, the last occurrence of the article "the" may include a sound pressure level of 40 dB, and the baseline value may be predetermined to be 45 dB, which provides a conclusion that the poem (at that point or the occurrence of the article "the") is unclear (i.e., negative clarity). The light source is thus controlled accordingly.

In more specific examples, the baseline value may be determined via other correlations, which may be based on at least a first occurrence of a repeating audio feature in the audio signal, for example. Namely:

in an embodiment, the processor may be configured to determine a respective value of the acoustic characteristic of the first occurrence of the repeating audio feature as a baseline value. Such an embodiment may be advantageous because the first occurrence of a repeating audio feature in the audio signal may set the baseline, thereby providing an unambiguous baseline from the outset.

Alternatively: in an embodiment, the processor may be configured to determine as the baseline value an average of respective values of the acoustic characteristic for each occurrence of the repeating audio feature. Such an average may for example be a moving average. Such an embodiment may be advantageous because the value of the acoustic characteristic (and thus the entire audio signal) at each respective occurrence of the repeating audio feature is taken into account in the setting of the baseline value. Thus, a more robust baseline value may be envisioned.

Alternatively: in an embodiment, the audio signal may further comprise a trigger feature to initiate the audio signal, wherein the trigger feature comprises a value of the acoustic characteristic; wherein the processor is configured to determine a value of an acoustic characteristic of the trigger feature as a baseline value. This advantageously enables control of the setting of the baseline value. Namely: introducing (or: inputting) the trigger characteristics into the acoustic signal allows to control the setting of the baseline by knowing the trigger characteristics in advance. For example, a presenter who knows that the word "baseline" may be the trigger feature may set a baseline value by intentionally stating the word.

As mentioned in part, the processor is configured to control the light sources of the lighting device to communicate the determined positive and/or negative clarity of the audio signal via the lighting characteristics. In other words, throughout all examples, the processor may control the light source to transmit an indication of the determined positive and/or negative sharpness via the lighting characteristic. The lighting characteristic thus indicates a certain positive and/or negative sharpness of the audio signal. Thus, the illumination characteristic outputs information on the sharpness. This advantageously enables feedback on the intelligibility of the audio signal to be provided via the light sources and lighting infrastructure; it is usually located at a significant position within the space and is therefore well suited to conveying information about the clarity of the acoustic signal.

In embodiments, the illumination characteristic may be light modulation, hue, color temperature, directionality, and/or light intensity. The hue may be referred to as a color. For example, positive sharpness may be conveyed by controlling the light source to emit a particular hue (such as green); and similarly, for negative clarity, the hue may be red.

For example, the light source of the lighting device may emit a specific light scene, but the color temperature may be controlled to be slightly warmer when a positive sharpness is detected, or slightly cooler if a negative sharpness is determined. Further, other combinations of color, hue, color temperature, directionality, intensity, etc. are contemplated.

Still further, in some of these embodiments, the optical modulation includes Li-Fi or visible light communication. Such an embodiment is advantageous because the light modulation may comprise more information about said sharpness of the acoustic signal. Additionally, the determined positive and/or negative intelligibility of the audio signal may thus be communicated to other devices equipped with VLC/Li-Fi receivers.

As mentioned in part above, real-time feedback on acoustic propagation in a space may be advantageous to obtain insight into acoustic comfort and/or acoustic clarity of sound that may originate from a sound source. To further improve the ergonomics and effectiveness of such feedback, the lighting device according to the invention may transmit a determined positive and/or negative clarity of the audio signal via the lighting characteristics in a specific direction, such as the direction of origin of the audio signal relative to the lighting device. Thus, in an embodiment, the light source may be a directional light source. Further, in further embodiments, the processor may be configured to: obtaining a direction of origin of the audio signal relative to the lighting device, and controlling the directional light source to convey a determined positive and/or negative sharpness of the audio signal via the lighting characteristic in said direction. Since the determined positive and/or negative sharpness is transmitted in the direction of the audio signal source via the illumination characteristic indicating said sharpness, the transmitted information about said sharpness is addressed to the correct source and/or in the most efficient direction (to transmit such information).

In an embodiment, the directional light source may be an indirect light source, wherein the indirect light source illuminates a surface area oriented in said direction. Such non-direct light sources may for example be concave light sources, decorative light sources, wall washing lights, ceiling washing lights, floor lights.

More specifically: in an embodiment, the processor may be configured to obtain the direction from a lighting system comprising an array of microphones. Such an embodiment may be advantageous in that the lighting device may receive information (wirelessly or via a wired connection) from other lighting devices according to the invention located elsewhere in the space (e.g. forming the lighting system according to the invention), such as e.g. microphone readings; from this information, the processor may determine the direction of origin of the audio signal relative to the lighting device, e.g., via triangulation or other well-known localization techniques.

Alternatively still, in an embodiment, the microphone may be a directional microphone and the processor is configured to obtain the direction from the directional microphone. Such an embodiment is advantageous in that the lighting device may be able to autonomously determine the direction of origin of the audio signal relative to the lighting device via said directional microphone. Alternatively, the microphone according to the invention may be a microphone array. Alternatively, the microphone may be embedded in the lighting device. The lighting device may thus be a luminaire. The microphone may also be part of an advanced sensor bundle (bundle) included with the lighting device, which may optionally provide a wireless communication means.

Still alternatively, in an embodiment, the microphones may be a first microphone and a second microphone, the first and second microphones being located at different positions on the lighting device. Such a local microphone array may also be suitable for determining the position of a sound source.

Since lighting devices are typically directed towards (i.e. have a lighting function) a function providing functional lighting and/or ambient lighting, the control of the light sources for communicating the determined positive and/or negative sharpness may in some cases be contradictory to the desire to provide said common lighting function. To solve this mentioned contradictory situation, the lighting device according to the invention may comprise at least one further light source. Hence, in an embodiment, the lighting device may comprise a further light source, wherein the further light source is arranged to provide ambient lighting and/or functional lighting.

The ambient lighting may for example be a light scene or an ambient setting. The functional lighting may for example be task light in a direction different from the direction in which the first light source delivers the determined sharpness. More specifically, a light source according to the invention may comprise a different and non-overlapping footprint (or footprint) than the footprint (footprint) comprised by the further light source. The ambient lighting may be white lighting. The further light source may be a conventional light source or alternatively an LED light source. The further light source may be a LED strip, or an array of light sources, or a downlight. The light source and the further light source may be controlled independently of each other.

The lighting device according to the invention may be located in an area of space. The audio signals may originate from sound sources within said space, which sources may for example be located in different areas of said space. If negative intelligibility can be determined according to the invention, the audio signal may therefore be unclear in said spatial region. Therefore, it may be an object to improve the intelligibility of the audio signal in said region. Thus, in an embodiment, the processor may be configured to: controlling the further light source to transmit at least a portion of the audio signal via a Li-Fi signal or a VLC signal if the processor determines a negative clarity of the audio signal. Such an embodiment is advantageous in that audio signals are forwarded in the area illuminated by the further light source of the lighting device by means of VLC and/or Li-Fi. Thus, a device having a VLC and/or Li-Fi receiver is able to receive the respective signal and reconstruct the audio signal.

For example, a person may be located in a distant corner of a theater and may be listening to a presenter's presentation, and at some point in time the person may not hear the presentation because the presenter's audio signals (i.e., speech) are no longer clear in the corner. Since the lighting device according to the invention may determine that the audio signal is not clear and communicate this information to the presenter, at the same time the further light source of the lighting device may forward said audio signal via VLC or Li-Fi signals (the audio signal as detected by the microphone but determined to be not clear with respect to said baseline value). The person's mobile device, located in a distant corner, may then receive the audio signal (i.e., speech) of the presenter on his mobile device and, for example, run an application to amplify or highlight the audio signal, e.g., convert the audio signal into written text that is displayed on the mobile device, so as to allow the person to follow.

Similarly, yet alternatively, in an embodiment, the lighting device may comprise a speaker, wherein the processor may be configured to: controlling a speaker to transmit at least a portion of an audio signal if the processor determines a negative intelligibility of the audio signal. Thus, if the clarity is negative in the region associated with the lighting device, the speaker may amplify the audio signal.

Alternatively still, in an embodiment, the lighting device may comprise a speaker, wherein the processor may be configured to: if the processor determines a positive intelligibility of the audio signal, the speaker is controlled to transmit a masking signal based at least in part on the audio signal. Such an embodiment is advantageous (e.g. when the audio signal is intended to be private) because the lighting device according to the invention has a speaker which transmits a masking signal to eliminate the intelligibility of the audio signal. This may be advantageous for open offices. Such sound cancellation and masking techniques are known in the art (e.g., for headphones).

It is a further object of the present invention to provide an improved system for determining and transmitting intelligibility of an audio signal which at least alleviates the above-mentioned problems and disadvantages. To this end, the invention also provides a system for determining and transmitting the intelligibility of an audio signal, wherein the system comprises at least two lighting devices according to the invention. Thus, advantages and/or embodiments applied to the device according to the invention may be compared to the system according to the invention. In aspects, the system may be a lighting system, or an array of light fixtures, for example.

In addition, the system may include a first lighting device and a second lighting device. In an embodiment, only the processor of the first lighting device may be configured to obtain a direction of origin of the audio signal relative to the lighting device, and to control the directional light source to communicate the determined positive and/or negative sharpness of the audio signal via the lighting characteristic in said direction. Thus, the first lighting device may take over said function of providing directed light from the second lighting device. This may be advantageous if the second lighting device may not have a view towards the source of the audio signal.

It is a further object of the present invention to provide an improved method which at least alleviates the above problems and disadvantages. To this end, the invention also provides a method of determining and conveying intelligibility of an audio signal, wherein the audio signal comprises a plurality of occurrences of a repeating audio feature, wherein each occurrence of the repeating audio feature comprises a respective value of an acoustic characteristic, wherein the method comprises: detecting an audio signal; determining a baseline value based on the audio signal; determining a positive sharpness of the audio signal if the last occurrence of the repeating audio feature comprises a respective value of the acoustic characteristic at least equal to the baseline value, or determining a negative sharpness of the audio signal if the last occurrence of the repeating audio feature comprises a respective value of the acoustic characteristic less than the baseline value, and controlling the light source to transmit the determined positive and/or negative sharpness of the audio signal via the illumination characteristic. Thus, the advantages and/or embodiments applied to the device according to the invention may be compared to the advantages and/or embodiments applied to the method according to the invention.

For example, in an embodiment, the method may further comprise: determining a respective value of the acoustic characteristic of the first occurrence of the repeating audio feature as a baseline value; or an average of respective values of the acoustic characteristic for each occurrence of the repeating audio feature is determined as a baseline value. In an embodiment, the method may include determining a value of an acoustic characteristic of a trigger feature as a baseline value, wherein the trigger feature initiates an audio signal and includes the value of the acoustic characteristic, wherein the audio signal includes the trigger feature.

For example, in an embodiment, the method may further comprise obtaining a direction of origin of the audio signal relative to the lighting device, and controlling the directional light source to convey the determined positive and/or negative clarity of the audio signal via the lighting characteristic in said direction. Thus, the method may further comprise obtaining the direction from a lighting system comprising an array of microphones, or wherein the microphones are directional microphones and the processor is configured to obtain the direction from the directional microphones.

For example, the method may further comprise providing ambient lighting with the further lighting device.

In aspects of the invention, in further examples, a predefined baseline value is specified, which may be determined by obtaining a parameter value. In such an example, a baseline value may thus be determined based on the audio signal in combination with the obtained parameter value. In an alternative example, the invention may be characterized in that the processor is configured to determine the baseline value based only on the parameter value.

Thus, in an embodiment, the processor may be configured to obtain the parameter value, wherein the parameter value may be indicative of one of: spatial geometry, an age of a person or an average age of people, an activity of a person or an activity of people, gestures, and/or objects within the identified space. The processor may be further configured to determine a baseline value based on the parameter value. Thus, the parameter values may for example be obtained from another device, such as a user input device (e.g. a smartphone or a remote control), or such as a sensor device (e.g. a camera detecting properties and/or activity of the space in which the lighting device is installed).

More specifically, the audio signal may for example propagate throughout the space in which the lighting device is present. The space may comprise a specific geometrical shape, which may be detected by a camera (internal to the lighting device (comprised by the lighting device) or external to the lighting device (separate from the lighting device)). The processor is configured to obtain a parameter value from the camera indicative of the particular geometry, and then determine a baseline value (taking the audio signal into account or not taking the audio signal into account) based on the parameter value. For example, an enclosed room may include a higher predefined baseline value than a high shed or open space with poor acoustic propagation properties.

Similar examples can be envisaged. For example, the space may include an audience (i.e., multiple people) performing an activity. The activity may be, for example, sitting, reading, dancing, etc. The predefined baseline value of a seated audience may be, for example, lower compared to a dancing audience, because the attention of the seated person is generally more appropriate for the acoustic intelligibility of the audio signal (such as, for example, the sound source of the presenter).

Similarly, the predefined baseline value may be based on an average age of a person (e.g., a presenter who generates the audio signal) or a plurality of persons (e.g., viewers who are listening to the presenter). Thus, the predefined baseline values for children, adolescents and/or elderly may differ. Similarly, objects may be detected within such a space, such as obstacles to acoustic propagation, such as compartments or curtains. The predefined baseline value may be based on the obtained parameter value indicative of the detected object. Similarly, the processor may obtain parameter values from a camera or other sensor.

Thus, in view of the above, in an embodiment, the lighting device may comprise a sensor for detecting an input value, wherein the processor is configured to determine said baseline value based on said detected input value. The sensor may be a PIR sensor, a temperature sensor, a biophysical sensor, a heart rate sensor, a camera, a light sensor, a thermopile array, an odor sensor, an RF receiver and/or a microphone, and/or a sensor bundle including any of the foregoing sensors. The input value may for example indicate: age, scent, subject, activity, identity of person, sound, geometry, density of people, etc.

As mentioned, in a more specific example, the baseline value may be determined via other correlations, which may be based on at least a first occurrence of a repeating audio feature in the audio signal, for example.

In further examples, the determined baseline value may be configurable and/or adjustable. Thus, in an embodiment, the processor is configured to adjust the determined baseline value based on an external input. External input may be received, for example, from a sensor (e.g., a camera) or a user input device (e.g., a smartphone). The external input may be, for example, the age of the audience, the language of the audience, the identity of the person(s), activity, gestures, and/or person density.

Thus, for example, the age and language level of the audience may have an effect on the desired intelligibility of the audio signal. Thus, the determined baseline may be dynamically re-adjusted during the audio signal based on feedback from the audience, e.g., via a smartphone app that determines the age and language level of the audience, or via a visual sensor that determines that the audience is experiencing difficulty understanding (e.g., a person whose hand is placed on the ear forming a cup gesture). The external input may also be a trigger for the start of an event. In other embodiments, the baseline value may be determined based on a baseline value of a previous audio signal.

In aspects, a system is provided comprising at least two lighting devices according to the invention, wherein the baseline value of a first lighting device is different from the baseline value of a second lighting device. This situation may occur because the first lighting device may be installed in a different area than the second lighting device. As mentioned above, the external inputs may thus be different, and thus the determined and/or adjusted baseline values are also different. Thus, the baseline value is locally adjustable based on the area in which the lighting device is installed.

Still further, in aspects of the present invention, there are provided: an actuator device for determining and conveying a intelligibility of an audio signal, wherein the audio signal comprises a plurality of occurrences of a repeating audio feature, wherein each occurrence of the repeating audio feature comprises a respective value of an acoustic characteristic, wherein the device comprises: an actuator; a microphone for detecting an audio signal; a processor configured to: receiving an audio signal from a microphone, determining a baseline value based on the audio signal, determining a positive clarity of the audio signal if the last occurrence of a repeating audio feature comprises a respective value of the acoustic characteristic at least equal to the baseline value, or determining a negative clarity of the audio signal if the last occurrence of a repeating audio feature comprises a respective value of the acoustic characteristic less than the baseline value, and controlling an actuator to transmit the determined positive and/or negative clarity of the audio signal via the illumination characteristic. The actuator may be a light source, sound source, RF beacon, vibrating device, heating device, or the like. Thus, advantages and/or embodiments applied to the lighting device according to the invention may be compared to the actuator device according to the invention.

Drawings

The invention will now be further elucidated by means of the schematic non-limiting drawings:

fig. 1 schematically depicts an embodiment of a lighting system according to the invention comprising a plurality of lighting devices according to the invention;

2A, 2B, and 2C schematically depict embodiments in which a baseline value is determined based on an acoustic signal;

fig. 3 schematically depicts an embodiment of a lighting device according to the present invention;

fig. 4 schematically depicts an embodiment of the method according to the invention.

Detailed Description

As mentioned above, real-time feedback on acoustic propagation in a space may be advantageous for obtaining insight into the acoustic comfort and/or acoustic intelligibility of sound originating from a sound source, such as for example a human being speaking can receive feedback on the intelligibility of his speech. It is therefore an object of the present invention to provide an improved lighting device which does not require to perform a computationally intensive semantic analysis and corresponding processing capabilities in order to determine the intelligibility of an audio signal and to communicate its information (e.g. as feedback to a sound source).

Fig. 1 schematically depicts by way of non-limiting example an embodiment of a lighting system 1000 according to the present invention. The lighting system 1000 comprises a plurality of lighting devices 100 according to the invention. The lighting system 1000 is installed in a theater 301, the theater 301 including a main stage 302 in front of the audience. The lighting device 100 is installed on the ceiling of the theater 301. The lighting device 100 is a luminaire. The luminaires 100 are thus distributed and network-entered initialized accordingly, i.e. their respective locations and control addresses are known. The lighting devices 100 are distributed in a grid, but may alternatively be distributed differently (such as randomly). Alternatively still, a single lighting device not explicitly depicted as part of the system may be sufficient to achieve the objects of the present invention.

The main stage 302 of the theater houses (host) the presenter 300. The presenter 300 is presenting and therefore emitting the audio signal 200. Thus, the audio signal 200 is human speech. The speech includes sentences and words. The audio signal 200 propagates through the theater 301. To facilitate the presenter 300 performing a presentation activity, it may be advantageous to communicate information to the presenter 300 regarding the clarity of his/her speech throughout the theater 301. This is met by the lighting device 100 according to the invention.

The audio signal 200 is a speech segment of the presenter 300. Here, the duration of the audio signal 200 is forty seconds. The segment may alternatively be of any other duration, such as ten seconds in duration, thirty seconds in duration, one minute in duration, or at least one minute in duration. The audio signal 200 comprises a plurality of occurrences of a repeating audio feature 201. Here, the repeated audio feature is the word "you". Fig. 1 schematically depicts six occurrences of a repeating audio feature 201. Alternatively, the repeating audio feature may be any other word, such as words that are often repeated in common sentences in the social interaction, e.g., "i", "large", "thank you", "how", "today", "we", "coupling", etc. Alternatively, the repeating audio feature may be a characteristic sound, a vowel, an article, a phrase, or a sentence.

Each occurrence of a repeating audio feature 201 in the audio signal 200 comprises a respective value 203 of the acoustic characteristic. Here, the acoustic characteristic is a Sound Pressure Level (SPL). Alternatively, the acoustic characteristic may be any other parameter suitable for acoustic characterization, such as for example frequency, timbre or tempo. Thus, each individual occurrence of the repeating audio feature 201 comprises a respective value 203 of the acoustic characteristic, i.e. SPL. (although fig. 1 does not number a distinction for each occurrence, a single reference numeral 201 is provided for each occurrence of a repeating audio feature and a reference numeral 203 is provided for its corresponding value in terms of acoustic properties).

Referring to fig. 1, the lighting device 100 comprises a directional light source 101. The directional light source 101 is arranged for illumination in a direction substantially horizontal to the ceiling of the theater 301, thereby providing a wall wash effect on the ceiling surface. Furthermore, the directional light sources 101 are arranged along the perimeter of the lighting device 100 and comprise segments along said perimeter, wherein each segment is individually controllable so as to allow directional lighting 10 in a specific direction relative to the lighting device 100. The directional light source may be, for example, a group of LED lights, a strip of LED lights, a group of spot lights, or a group of halogen lights, among others. The lighting device 100 further comprises a second light source 104. The second light source 104 is an LED light source that provides ambient lighting 40. Thus, the ambient lighting 104 is arranged for illuminating the theater 301 and providing desired lighting conditions therein. For example, the ambient lighting 104 may comprise a (dynamic) lighting scene or, for example, functional lighting.

The lighting device 100 further comprises a microphone 102 and a processor 103. The microphone 102 listens to sounds within the theater 301 and is able (in cooperation with the processor's talent) to identify and/or distinguish the audio signals 200 of the presenter 300. Thus, the microphone 102 and processor 103 are able to cooperatively receive a forty second segment of the audio signal 200 and identify the repeating audio feature 201 of the word "you" therein; and the SPL value 203 for each occurrence of the word "you" in the audio signal 200.

The lighting device 100 further comprises a transceiver 105 for wireless communication with other lighting devices according to the present invention. Thus, sensor data may be exchanged. The wireless communication is via ZigBee. Alternatively, each lighting device may exchange sensor data via a bluetooth, RF, IR, VLC, Li-Fi, and/or UWB connection, which may be facilitated by the transceiver 105. However, the transceiver is optional, and alternate embodiments may not need to have such a transceiver.

Still referring to fig. 1, the microphone 102 detects the audio signal 200 and forwards the detected audio signal 200 to the processor 103 (i.e., data such as the detected audio signal 200). The processor 103 receives the audio signal 200 from the microphone 102 and determines a baseline value 202 of the acoustic characteristic based thereon. The processor 103 determines a baseline value 202 based on at least a first occurrence of a repeating audio feature 201 in the audio signal 200 and its corresponding SPL acoustic characteristic value 203. Here, as depicted in fig. 1, the baseline value 202 is determined by the processor selecting a corresponding value 203 of the acoustic characteristic (i.e., SPL) of the first occurrence of the repeating audio feature 201 as the baseline value 202.

In addition, at each subsequent occurrence of the repeating audio feature 201, the processor 103 of the lighting device 100 is able to determine the intelligibility of the audio signal 200. Thus, the clarity of the audio signal 200 is evaluated at the respective positions of the respective lighting devices within the theater 301. The location represents a portion of the theater 301. The clarity is positive if the value 203 of the corresponding subsequently occurring acoustic characteristic (i.e., SPL) of the repeating audio feature 201 is at least equal to the baseline value 202; or conversely, if the value 203 of the corresponding subsequently occurring acoustic characteristic (i.e., SPL) of the repeating audio feature 201 is less than the baseline value 202, then the intelligibility is negative.

Thus, considering that the audio signal 200 has been completely detected and that all six occurrences of the audio signal 200 are repeated, the processor 103 determines in this embodiment the positive sharpness of the audio signal 200; because the last occurrence of the repeating audio feature 201 includes a corresponding value 204 of the acoustic characteristic (i.e., SPL) that is greater than the baseline value 202.

In an alternative embodiment similar to that depicted in fig. 1, the baseline may be determined differently. In the embodiment schematically depicted in part in fig. 2A, the processor determines the average 1202 by considering the SPL for each of six occurrences of repeating audio features. This average 1202 is then taken as the baseline value.

In the embodiment partially schematically depicted in fig. 2B, the audio signal includes a trigger feature 2201 that initiates the audio signal. The trigger feature 2201 is the phrase "can you hear me". The microphone receives the audio signal and the processor identifies the trigger feature 2201. The trigger feature thus initiates the audio signal being evaluated by the processor. Still alternatively, the audio signal may have been initiated in other ways, and the trigger feature may be identified during the beginning and end of the audio signal. In addition, the processor determines a value 2202 of the acoustic characteristic (i.e., SPL) of the trigger feature 2201 as a baseline value.

In the embodiment schematically depicted in part in fig. 2C, the baseline value is a predefined threshold 3202. Predetermined threshold 3202 may depend on the audio signal. The predefined threshold 3202 may be provided to a processor of the lighting device during network entry initialization and/or installation. Alternatively, it may be set by the presenter by means of a user input device which is wirelessly connected with the lighting device via said transceiver. This also advantageously allows the presenter and/or network entry initializer to customize the predefined threshold for each individual lighting device in the theater. Thus, in view of the determination of the intelligibility of the audio signal, means are advantageously provided for adjusting the sensitivity of the lighting device.

Referring back to fig. 1, in determining the positive clarity of the audio signal 200, the processor 103 controls the directional light source 101 and transmits the determined positive clarity into the theater 301 in the direction of the presenter 300. The section of the directional light source 101 pointing in said direction is then controlled to emit light comprising a specific illumination characteristic. Here, the illumination characteristic is green, but may alternatively be any other illumination characteristic, such as modulation, color temperature, pattern, light intensity, etc. Here, the processor determines the direction, which is the direction of origin of the audio signal 200 with respect to the lighting device 100, by evaluating information related to the acoustic signal 200 (received by at least one other microphone of another lighting device 100 in the theater 301), which information is exchanged via said wireless communication link implemented by the transceiver 105. Since the lighting devices 100 of the lighting system 1000 are arranged in a grid and comprise microphones, acoustic localization is possible when the lighting devices are communicating and share measurement data of their respective microphones.

Alternatively, in embodiments in which the lighting device operates autonomously without feedback from other devices, the microphone may be a directional microphone and the processor obtains the direction (and/or its measurement data provided) from the directional microphone. The directional microphone may also be understood as two microphones comprised by the lighting device having a predefined distance between them, thus being a local microphone array. Alternatively still, in such an autonomous embodiment, the direction may be estimated by the processor with a certain degree of accuracy by means of computational analysis. Furthermore, in an embodiment, the direction may be provided by means of a user input, such as a manual configuration step indicating the direction of, for example, a stage in a theater.

In summary, the processor 103 controls the directional light source 101 to deliver a determined positive sharpness in a determined direction, i.e. by controlling the respective section of the directional lighting device corresponding to said direction.

Thus, the lighting device 100 according to the present invention exploits the insight that each occurrence of a repeating feature 201 in an audio signal 200 comprises a respective value 203 of an acoustic characteristic, thereby determining a sharpness (i.e. positive or negative sharpness) of the audio signal 200 and subsequently communicating the determined sharpness, in order to provide feedback on said sharpness of the audio signal 200. The processor 103 is thus configured to determine the intelligibility of the audio signal 200 by comparing the corresponding value 204 of the last occurrence of the repeating audio feature 201 with the baseline value 202.

In a non-limiting embodiment (not depicted), which is similar in part to the embodiment depicted in fig. 1, a second light source providing ambient lighting is adapted to emit a light communication signal (VLC or Li-Fi). If the processor determines a negative clarity, after determining an instance of that clarity and until a new clarity is determined, the portion of the audio signal received by the microphone and processed by the processor is converted to an optical communication signal and emitted by the second light source into the theater. Mobile devices with optical communication receivers can receive the signal and convert back to audio or text, or alternatively use the data for other applications. An audience that may not be able to receive a clear audio signal from a presenter may thus be provided with an optical communication signal that provides the audio signal, such that the audience may still be able to follow the presentation, or at least follow it with e.g. subtitles or commentary.

Alternatively, in a further non-limiting embodiment (not depicted), which is partly similar to the embodiment depicted in fig. 1, the lighting device comprises a speaker. If the processor determines a negative intelligibility, after determining an instance of that intelligibility and until determining a new intelligibility, a portion of the audio signal received by the microphone and processed by the processor is transmitted to the theater via the speaker. This facilitates the local supplementation of the audio signal of the presenter.

Fig. 3 schematically depicts by way of non-limiting example an embodiment of a lighting device 700 according to the present invention. The lighting device 700 comprises a light source 701, a microphone 702 and a processor 703. The lighting device 700 is a light emitting ceiling panel. This may be advantageous because the light emitting ceiling panels are structurally mounted in the space. The lighting device 700 is installed on the ceiling of the open office area 751. The open office 751 further includes an array of light-emitting ceiling panels, of which the lighting device 700 is one. Here, by way of non-limiting example, all of the light-emitting ceiling panels operate autonomously. The open office 751 also includes a speaking person 750. The person 750 may be, for example, in a confidential conversation/conference and want to evaluate how clear his speech is.

The person 750 is the sound source because he/she is speaking. Thus, the person 750 generates the audio signal 800. Thus, the audio signal 800 is human speech. The speech includes sentences and words. Audio signal 800 propagates through open office space 751. Thus, each instance of the audio signal at each time is the last 30 seconds of human speech. Alternatively, other time periods may be considered, such as time periods of less than one minute or less than five minutes.

The audio signal 800 includes multiple occurrences of repeating audio features. The repeating audio feature is a vowel "O". Each occurrence of a repeating audio feature in the audio signal 200 comprises a corresponding value of the acoustic characteristic. Here, the acoustic characteristic is an acoustic frequency (i.e., pitch) of a vowel. Thus, the audio signal comprises multiple occurrences of the vowel "O", where each occurrence is characterized by its corresponding frequency value.

The microphone 702 of the lighting device 700 detects the audio signal and forwards its measurements to the processor 703. The processor 701 receives an audio signal from the microphone 702 and determines a baseline value based on the audio signal 800. Namely: the baseline value is selected as the frequency value of the first occurrence of the vowel "O" in the audio signal 800.

The processor 703 of the lighting device 700 then determines the positive clarity of the audio signal 800 if the last occurrence of the repeating audio feature has a frequency value at least equal to the baseline value. The processor 703 of the lighting device 700 then determines the negative clarity of the audio signal 800 if the last occurrence of the repeating audio feature has a frequency value that is less than the baseline value. Here, the processor 703 determines positive clarity because the human audio signal is clear. Similarly, the other light-emitting ceiling panels 760 in the array also determine positive clarity based on their own autonomous evaluation. However, some other light emitting ceiling panels 770 in the array inversely determine negative clarity based on their own autonomous evaluation. The latter light-emitting ceiling panels are located, for example, farther away from a person, or in sound attenuation locations within the open office area 751 (e.g., due to compartments, curtains, glass, vegetation, etc.).

As a result of the determined positive definition, the processor 703 controls the light source 701 to emit a blinking blue light to convey the determined positive definition to the person 750 and into the open office 751. Similarly, the light-emitting ceiling panel 760 with a certain positive definition does so. Conversely, the light-emitting ceiling panel 770 having a certain negative definition emits red light, or is alternatively turned off. As previously mentioned, other lighting characteristics are also contemplated. The communicated sharpness (or indication of sharpness) may be through a change in color temperature, such as a shift of 10 degrees kelvin, or through various known types of optical communication, for example.

Thus, since the lighting device 700 does not need to interpret the meaning of the repetitive audio features and/or does not need to perform semantic analysis on the intelligibility, the present invention advantageously provides a more computationally and/or power efficient means for determining and transmitting intelligibility of an audio signal, which is an advantageous feedback to the person 750.

Fig. 4 schematically depicts by way of non-limiting example a method 900 of determining and communicating the intelligibility of an audio signal. The audio signal thus comprises a plurality of occurrences of the repeating audio feature, wherein each occurrence of the repeating audio feature comprises a respective value of the acoustic characteristic. The acoustic characteristic may be SPL or frequency, for example.

The first step 901 of the method is to detect an audio signal with a microphone. A second step 902 is to determine a baseline value based on the audio signal, as set forth in the previous example. Thus, there may be sub-steps in determining the baseline value, such as, for example: a step 9021 of determining a corresponding value of the acoustic characteristic of the first occurrence of the repeating audio feature as a baseline value; or a step 9022 of determining as a baseline value an average of respective values of the acoustic characteristic for each occurrence of the repeating audio feature; or determining 9023 an acoustic characteristic value of a trigger feature that initiates the audio signal and that includes the acoustic characteristic value as a baseline value, where the audio signal includes the trigger feature.

The third step 903 comprises: a positive intelligibility of the audio signal is determined if the last occurrence of the repeating audio feature comprises a corresponding value of the acoustic characteristic at least equal to the baseline value, or a negative intelligibility of the audio signal is determined if the last occurrence of the repeating audio feature comprises a corresponding value of the acoustic characteristic less than the baseline value.

A fourth step 904 comprises controlling the light source to communicate the determined positive and/or negative clarity of the audio signal via the lighting characteristic.

In an embodiment (not depicted), the method may further comprise obtaining a direction of origin of the audio signal relative to the lighting device, and controlling the directional light source to convey the determined positive and/or negative clarity of the audio signal via the lighting characteristic in said direction. In an embodiment (not depicted), the method may further comprise providing ambient lighting with a further lighting device.