Acoustic camera system

Abstract

An acoustic camera system (1) comprises a microphone unit (3) and a mobile device (2), in particular a tablet or smartphone, wherein the mobile device includes a camera (22), a data interface (41), and a display (25). The microphone unit (3) includes a data interface (42) which is connected or connectable to the data interface (41) of the mobile device (2) via a connection (4). The microphone unit (3) includes a microphone array (32) with a plurality of microphones (32a) and an evaluation unit (31) which receives data from the microphones (32a).

Description

[0001] The invention relates to an acoustic camera system.

[0002] Appropriate camera systems are used to locate sound sources and visualize them on a display. A sound source is detected via a microphone array, providing spatial acoustic data about the source. Simultaneously, the area around the sound source is recorded by a camera. By combining the spatial signal data from the microphone array with the recorded video image, the sound source can be identified within the video image.

[0003] Due to the abundance of data generated by recording the acoustic signals captured via the microphone array, a relatively high computing power is required to process the corresponding data in real time.

[0004] Due to the required computing power, the application of an acoustic camera is limited, especially in mobile use. This is because conventional portable mobile devices are generally not equipped with the capabilities to process complex signals in real time.

[0005] The invention is therefore based on the objective of further developing an acoustic camera system of the type mentioned above in such a way that it is particularly suitable for mobile use.

[0006] This problem is solved by an acoustic camera system with the features of claim 1. Advantageous embodiments are found in the dependent claims.

[0007] An acoustic camera system according to the invention comprises a microphone unit and a mobile device, in particular a tablet or smartphone, wherein the mobile device includes a camera, a data interface, and a display. Here, mobile devices that are common and therefore widely available on the market are deliberately used as the base device. The microphone unit of the acoustic camera system according to the invention includes a data interface that is coupled or can be coupled to the data interface of the mobile device. The microphone unit is thus an add-on to the mobile device and is connected to it via a corresponding interface. Furthermore, the microphone unit of the acoustic camera system according to the invention includes a microphone array with a plurality of microphones and an evaluation unit that receives data from the microphones. The microphone array allows the sound sources to be resolved directionally and spatially.Since the evaluation of the data collected by the microphone array can place a heavy or even excessive strain on a mobile device, a separate evaluation unit is housed in the microphone unit, which evaluates or at least pre-evaluates the data.

[0008] Preferably, the evaluation unit comprises an FPGA or ASIC. This allows for the use of an evaluation unit specific to the microphone unit, which can be pre-programmed or programmable on-site. The use of application-specific standard products can reduce costs.

[0009] It has proven advantageous that the microphone unit is powered via the mobile device's power supply, particularly in the form of a battery, through the connection. This allows the microphone unit to be built compactly and lightweight, making the entire acoustic camera system easy to handle as a mobile device.

[0010] It is also advantageous if the microphone unit is connected or connectable to the mobile device via a mechanical coupling. This strengthens the unity of the mobile device and microphone unit, which underscores the nature of a mobile acoustic camera.

[0011] It has proven particularly advantageous to have software installed on the mobile device that is configured to receive data from or transmit data to the evaluation unit, and / or to display information concerning the data generated by the evaluation unit and / or an image or video generated by the camera. The software installed on the mobile device is configured to communicate with the evaluation unit of the microphone unit. For example, it can transmit images from the optical camera and store the evaluated data from the microphone unit and / or make it available via the output devices available on the mobile device, such as the screen and / or speakers / headphones.For example, if the image from the acoustic camera is combined with that from the optical camera, a noise source can be easily located, and an acoustic output of the noise via the speaker / headphones can then provide the user with further information.

[0012] For optical output, a touchscreen display unit has proven particularly advantageous. By selecting specific areas, the microphone array can be focused on particular points to examine specific sound sources more closely.

[0013] The invention will be explained in more detail using an exemplary embodiment and the following figures. Figure 1 shows a perspective view of an acoustic camera system based on a smartphone. Figure 2 also shows a perspective view of the acoustic camera system, with the microphone unit detached from the mobile device. Figure 3 shows a block diagram of an acoustic camera system.

[0014] Figure 2 Figure 1 shows a perspective view of the two main elements 2 and 3 of an acoustic camera system 1. In this embodiment, the mobile device 2 is a smartphone, shown from the rear 26, because it would not be practical to position the microphone unit 3 on the front of the display 25, the screen. The optical camera 22 is located in the upper left corner of the rear 26. The data interface 41 of the mobile device 2 is also important for the acoustic camera system 1.

[0015] The microphone unit 3 is shown above the mobile device 2. On the side facing away from the mobile device 2, a microphone array 32, consisting of a plurality of microphones 32a, is arranged. The microphone array 32 is coupled to the evaluation unit 31, which is provided with a data interface 42 adapted to the mobile device.

[0016] In Figure 1The two parts 2 and 3 of the acoustic camera system 1, the mobile device 2, and the microphone unit 3 are joined together. The data interface of the microphone unit 42 is connected to the data interface 41 of the mobile device 2, thereby activating the acoustic camera system. The microphone unit 3 is detachably mounted on the rear 26 of the mobile device 2. In this embodiment, the dimensions of the microphone unit 3 are smaller than those of the mobile device 2. This has the advantage that the forces holding the microphone unit 2 on the mobile device 2 can be low, since there is little surface area for forces that could lift the microphone unit 3 from the mobile device 2. Thus, the microphone unit 3 can be designed to be held by van der Waals forces, slight adhesive forces, or other adhesion forces.In this case, the microphone unit 3 can also be held quite flexibly, as its dimensional stability is ensured by its conformity to the mobile device 2. Of course, other mounting options are also conceivable, such as magnetic connections or form-fit and / or force-fit connections like clip connections. While a larger surface area of ​​the microphone unit 3 increases the resolution of the measurements, it requires greater internal stability, which would make the acoustic camera system 1 more difficult to handle.

[0017] Figure 3 Figure 1 shows the block diagram of an acoustic camera system 1 according to the invention. The mobile device 2 has a power supply 20 for operating the device. Software 21 is installed on the mobile device 2, which communicates with the camera 22 and possibly other sensors 23 via an interface 24 and can control the output 25, a screen and / or a speaker.

[0018] If the microphone unit 3 is connected to the mobile device 2 via the connection 4 with the interfaces 41, 42, the microphone unit is also supplied with voltage 30 via the connection, unless the microphone unit 3 has its own power supply 30. The microphone unit is attached to the mobile device 2 by means of a mounting system 33, preferably on the rear 26 of the mobile device 2.

[0019] The evaluation unit 31 analyzes the data from the microphone array 32 and transmits the evaluation data to the software 21 via connection 4. Depending on the settings, the software 21 can combine the data from the microphone array 32 with the images from an integrated optical camera 22 and display them on the screen 25. This allows for real-time acoustic analysis, enabling the detection and potential elimination of acoustic disturbances. For this purpose, the software 21 can control the evaluation unit 31 to focus on specific spatial directions and distances, thus providing a more detailed picture of the environment.

[0020] It is also possible that the software 21 stores the evaluation data of the evaluation unit 31 together with data from sensors and / or the optical camera 22 and thus makes it available for later extensive evaluation.

[0021] An acoustic camera system 1 according to the invention provides a lightweight and cost-effective device that allows for quick and easy deployment in the field. It is cost-effective primarily because a standard mobile device 2 is used, and only the necessary software needs to be installed and a microphone unit connected.

[0022] It is also possible to change the number of microphones 32a in the microphone array 32. Using fewer microphones 32a reduces energy consumption and processing time, although spatial resolution decreases. If the selection of microphones 32a is electronic, an energy-efficient acoustic overview can be created with just a few microphones 32a. At points of interest, a more detailed analysis can be performed by adding more microphones 32a to increase spatial and acoustic resolution. Reference symbol list:

[0023] 1 Acoustic camera system 2 Mobile device 3 Microphone unit 4 Connection 20 Power supply 21 Software 22 Camera 23 Sensor (other) 24 Interface 25 Display 26 Rear panel 30 Power supply 31 Evaluation unit 32 Microphone array 32a Microphone 33 Mounting system 41 Data interface 42 Data interface

Claims

1. Acoustic camera system (1) comprising a microphone unit (3) and a mobile device (2), in particular a tablet or smartphone, wherein the mobile device comprises a camera (22), a data interface (41) and a display (25), wherein the microphone unit (3) comprises a data interface (42) which is coupled or can be coupled to the data interface (41) of the mobile device (2) via a connection (4), wherein the microphone unit (3) comprises a microphone array (32) with a plurality of microphones (32a) and an evaluation unit (31) which receives data from the microphones (32a).

2. Acoustic camera system (1) according to claim 1, wherein the evaluation unit (31) comprises an FPGA or ASIC.

3. Acoustic camera system (1) according to one of the preceding claims, in which the microphone unit (3) is supplied with voltage via the power supply (20), in particular in the form of a battery of the mobile device (2) via the connection (4).

4. Acoustic camera system (1) according to one of the preceding claims, wherein the microphone unit (3) is connected or connectable to the mobile device (2) via a mechanical coupling.

5. Acoustic camera system (1) according to one of the preceding claims, in which software (21) is installed on the mobile device which is configured to receive data from the evaluation unit (31) or to transmit data to the evaluation unit (31), and / or to display information relating to the data generated by the evaluation unit (31) and / or an image or video generated by the camera (22) on the display (25).

6. Acoustic camera system (1) according to one of the preceding claims, wherein the display unit is designed as a touchscreen.

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