JP2009004959A - Mobile device - Google Patents

Abstract

A portable terminal capable of automatically and reliably switching between a voice call mode and a videophone mode by reliably determining whether or not the portable terminal is in the vicinity of a user's ear.
A distance sensor detects a distance between a portable terminal and a user. The brightness measuring unit 12 determines the output level of the camera-captured image from the image processing unit 7 and measures the brightness of the subject. The face recognition unit 13 analyzes the camera-captured image from the image processing unit 7 and recognizes the face of the subject. The control unit 11 sets the videophone mode when the distance is greater than or equal to a predetermined value, maintains the videophone mode when the distance is less than the predetermined value and recognizes the face, and the distance is equal to the predetermined value. If the face is not recognized and the brightness is greater than or equal to a predetermined value, the videophone mode is maintained, and the distance is less than or equal to a predetermined value and the face is not recognized and the brightness is less than or equal to a predetermined value. Is controlled to switch to the voice call mode.
[Selection] Figure 2

Description

  The present invention relates to a portable terminal that automatically switches between a voice call mode and a videophone mode.

(Patent Document 1)
There is a mobile phone device that automatically sets an operating environment depending on whether it is used as a telephone or a camera (see, for example, Patent Document 1). In this cellular phone device, the distance between the device main body and the user of the device main body is measured by the distance sensor, and the input voice level by the microphone is measured, so that the device main body is at a normal call position (near the user's ear). Judgment whether or not. Based on this determination, the operating environment is automatically switched and set.

(Patent Document 2)
There is a portable terminal device that automatically switches between a voice call mode and a videophone mode (see, for example, Patent Document 2). In this portable terminal device, a luminance signal is extracted from the video signal from the camera 21, and the CPU 7 determines a call mode between a videophone mode and a voice call mode from information on the luminance signal. That is, in the voice call mode using the receiver 13, the camera is pressed against the face, so that the luminance signal is extremely small. If the luminance of the shooting target is low, it is determined that the voice call mode is selected, and the receiver 13 is automatically switched. If the luminance of the shooting target is high, it is determined that the videophone mode is selected, and the speaker is automatically switched to the loudspeaker 14.
JP 2002-111801 (Page 1, FIG. 1, FIG. 5) JP 2001-54085 A (paragraph numbers 0017-18, FIG. 4)

  In the cellular phone device of Patent Document 1, when the user is not speaking, there is a problem that the input voice level cannot be measured by the microphone, and it cannot be determined whether it is a normal call position (near the user's ear). .

  In the portable terminal device of Patent Document 2, it is determined whether the camera is pressed against the face based on the magnitude of the luminance signal. However, the magnitude of the luminance signal also changes when other factors such as entering the house from outside the house. For example, when using the videophone mode outdoors, when entering indoors, there is a problem that it becomes dark rapidly and switches to the voice call mode. In other words, the position of the camera and the way it is exposed to light change, and it may occur that it is wrong to determine whether the camera is pressed against the face.

  The present invention solves such problems and reliably determines whether a portable terminal is in the vicinity of the user's ear, thereby automatically switching between a voice call mode and a videophone mode. The purpose is to provide a terminal.

  In order to achieve the above object, a mobile terminal of the present invention is a mobile terminal equipped with a camera for capturing an image, a speaker and a microphone for voice call, and a voice call mode using the speaker and microphone; Switching means for switching the videophone mode using the camera, speaker and microphone, distance detecting means for measuring the distance to the user, and face recognition for performing face recognition based on an image captured via the camera Means, a brightness measuring means for measuring ambient brightness, and a distance measured by the distance detecting means is greater than or equal to a predetermined distance, the switching means is controlled to set the videophone mode, If the distance is equal to or less than a predetermined distance, the face recognition unit does not recognize the face and the luminance measured by the luminance measurement unit is a predetermined luminance. Characterized by comprising a control means for setting a voice call mode when below.

  According to the present invention, it is possible to reliably determine whether or not the mobile terminal is in the vicinity of the face, and it is possible to automatically switch between the voice call mode and the videophone mode without fail.

  FIG. 1 is an external view of a mobile terminal according to an embodiment of the present invention. The mobile terminal 100 includes the speaker 3, the camera 6, the distance sensor 10, the display unit 8, and the like on the upper housing 21 side. The operation key 9 and the microphone 4 are mounted on the lower housing 22 side.

  The speaker 3 functions as an audio receiver having a low volume when used in the vicinity of the user's ear, such as an audio call mode (receiver call mode). When used in a position away from the user's ear, such as a videophone mode, it functions as a loud speaker. The speaker 3 may be composed of a voice call receiver and a video phone mode speaker.

  The camera 6 is a camera that takes a self-portrait of the user. The distance sensor 10 measures the distance between the mobile terminal 100 and the user by infrared reflection. The display unit 8 is a display unit such as an LCD.

  The operation key 9 is a user operation input means. When the microphone 4 is used at the user's mouth such as a voice call mode, the microphone sensitivity is set low. When used at a position away from the user's mouth such as a videophone mode, the microphone sensitivity is set high.

  FIG. 2 is a block diagram of relevant portions of the mobile terminal according to the embodiment of the present invention. The mobile terminal 100 includes an antenna 1, a communication unit 2, a speaker 3, a microphone 4, a call unit 5, a camera 6, an image processing unit 7, a display unit 8, operation keys 9, a distance sensor 10, a control unit 11, and the like. .

  The control unit 11 includes a CPU, a ROM, a RAM, and the like (not shown) and executes main functions of the mobile terminal 100. The control unit 11 includes a luminance measurement unit 12 and a face recognition unit 13 particularly in the present invention.

  The antenna 1 transmits and receives radio waves to and from a base station (not shown). The communication unit 2 performs processing such as transmission / reception of radio signals, amplification, and modulation / demodulation. The speaker 3 is used for receiving a voice and other sound. The microphone 4 is used for voice input such as transmission.

  The call unit 5 converts the digital audio signal transmitted from the communication unit 2 into an analog audio signal, amplifies it, and sends it to the speaker 3. Further, the analog audio signal transmitted from the microphone 4 is amplified, converted into a digital audio signal, and transmitted to the communication unit 2.

  The camera 6 is a photographing means such as a CCD. The image processing unit 7 performs image processing of the camera 6. The display unit 8 is a display unit such as an LCD. The operation key 9 is a user operation input means. The distance sensor 10 measures the distance between the mobile terminal 100 and the user by infrared reflection.

The luminance measuring unit 12 of the control unit 11 determines the output level of the camera-captured image from the image processing unit 7 and measures the luminance of the subject.
The face recognition unit 13 analyzes the camera-captured image from the image processing unit 7 and recognizes the face of the subject. The face recognition algorithm is disclosed as a face recognition unit in paragraph No. 0022 of Japanese Patent Application Laid-Open No. 2007-20033, and detailed description thereof is omitted here.

  FIG. 3 is an operation flowchart of the control unit of the mobile terminal according to the embodiment of the present invention. When the conversation mode is started, the control unit 11 enters a conversation state (step S1).

  The conversation mode is a voice call mode (receiver call mode) or a videophone mode. From the viewpoint of protecting the user's ears, the voice call mode is set as a default and starts. The voice call mode setting is a setting in which the camera 6, the display unit 8, and a lighting unit (not shown) of the display unit 8 are turned off, the volume of the speaker 3 is low, and the sensitivity of the microphone 4 is low.

  And the distance measurement by the distance sensor 10 is performed (step S2). If this distance is greater than or equal to the predetermined distance in step S3, it is clear that there is no user in the vicinity of the portable terminal 100, and only in this case, the videophone mode setting is switched (step S30).

  In the videophone mode setting, the camera 6, the display unit 8, and the illumination unit (not shown) of the display unit 8 are turned on (step S31). Further, the volume of the speaker 3 is set to be high (step S32). Further, the sensitivity of the microphone 4 is set to be large (step S33).

  On the other hand, when the distance measured by the distance sensor 10 in step S3 is equal to or less than the predetermined distance, the mobile terminal 100 is not necessarily near the user's ear. The determination process after step S4 is executed without switching to the videophone mode setting.

  First, the on / off state of the camera 6 for which the mode has already been set is checked (step S4).

  If the camera 6 is off in step S4, it is already in the voice call mode. In this case, the following voice call mode setting process in steps S10 to S23 is passed, and the conversation in step S40 is ended. If the check is entered and not completed, the process returns to step S1 and loops.

  On the other hand, if the camera 6 is on in step S4, it is already in the videophone mode, and the distance sensor is not more than a predetermined distance in step S3 described above and is not necessarily near the ear. It is determined whether or not the mobile terminal 100 is near the user's ear by image analysis (steps S10 to S14).

  In camera image analysis, first, face recognition processing is performed (step S11). If YES in step S12, it means that the outline of the face has been recognized, that is, it means that the camera 6 and the user are some distance apart. Therefore, it is determined that the mobile terminal 100 is not near the user's ear, and the voice call mode setting in steps S20 to S23 is passed.

  On the other hand, if NO in step S12, it is possible that the face outline is approaching so that the outline of the face is not recognized, and luminance measurement processing is performed (step S13). If the brightness is equal to or higher than the predetermined value in step S14, that is, if the brightness is bright, it is determined that the mobile terminal 100 is not near the user's ear, assuming that the camera 6 is not blocked by the user's face and that there is external light. The voice call mode setting in steps S20 to S23 is passed.

  If the brightness is equal to or lower than the predetermined value in step S14, that is, if the brightness is dark, it is determined that the camera 6 is blocked by the user's face and the mobile terminal 100 is in the vicinity of the user's ear. The mode is switched to the mode setting (step S20).

  In the voice call mode setting, the camera 6, the display unit 8, and the illumination unit (not shown) of the display unit 8 are turned off (step S21). Further, the volume of the speaker 3 is set to a low level (step S22). Further, the sensitivity of the microphone 4 is set to a small value (step S23).

  Then, the conversation end check in step S40 is entered, and if not ended, the process returns to step S1 to repeat the loop.

  As described above, according to the embodiment of the present invention, the combination of the distance sensor, the camera image face recognition process, and the camera image luminance measurement process ensures that the mobile terminal is near the user's ear. Thus, it is possible to automatically switch between the voice call mode and the videophone mode without fail.

  In the above description, the voice call mode and the videophone mode are determined based on the distance determination by the distance sensor, the determination of whether or not the face can be recognized using the face recognition process, and the determination of the brightness level by the brightness measurement process. The switching process has been explained. Regardless of these judgment results, the mode is always fixed to the voice call mode or the videophone mode, and the mode automatic selection is automatically switched between the voice call mode and the videophone mode according to the judgment result. It is also possible for the user to select

  In addition, even when switching between the voice call mode and the videophone mode based on the above determination, it may be inconvenient for the user if the mode is frequently switched every time each determination is changed. For this reason, for example, by not performing each determination operation for a predetermined time after the mode is switched, it is possible to suppress the occurrence of a situation in which the mode is frequently switched.

The external view of the portable terminal which concerns on the Example of this invention. The block diagram of the relevant part of the portable terminal which concerns on the Example of this invention. The operation | movement flowchart of the control part of the portable terminal which concerns on the Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Antenna 2 Communication part 3 Speaker 4 Microphone 5 Calling part 6 Camera 7 Image processing part 8 Display part 9 Operation key 10 Distance sensor 11 Control part 12 Luminance measurement part 13 Face recognition part 21 Upper housing | casing 22 Lower housing 100 Portable terminal

Claims (4)

In a mobile terminal equipped with a camera for shooting images, a speaker and a microphone for voice calls,
A switching means for switching between the voice call mode using the speaker and the microphone and the videophone mode using the camera, the speaker and the microphone;
Distance detection means for measuring the distance to the user;
Face recognition means for performing face recognition based on an image captured via the camera;
Luminance measuring means for measuring ambient luminance;
When the distance measured by the distance detection means is greater than or equal to a predetermined distance, the switching means is controlled to set the videophone mode, and when the distance is less than or equal to the predetermined distance, the face recognition means And a control means for setting a voice telephone mode when the brightness measured by the brightness measuring means is equal to or lower than a predetermined brightness.   When the control unit controls the switching unit to switch to the voice call mode or the video phone mode, the mode switching control is not performed for a certain period of time after the switching is performed. The mobile terminal according to claim 1, wherein the mobile terminal is controlled as follows. A portable terminal having a voice call mode and a videophone mode by a voice receiver,
Photographing means for photographing an image for the videophone mode;
Luminance measuring means for measuring luminance from the image signal of the photographing means;
Face recognition means for recognizing a human face from the image signal of the photographing means;
When the face is recognized, the videophone mode is maintained, when the face is not recognized, and when the luminance is equal to or higher than a predetermined value, the videophone mode is maintained, the face is not recognized, and the luminance And a control means for switching to the voice call mode when is below a predetermined value. A portable terminal having a voice call mode and a videophone mode by a voice receiver,
Distance detection means for detecting the distance between the mobile terminal and the user;
Photographing means for photographing an image for the videophone mode;
Luminance measuring means for measuring luminance from the image signal of the photographing means;
Face recognition means for recognizing a human face from the image signal of the photographing means;
When the distance is equal to or greater than a predetermined value, the videophone mode is set. When the distance is equal to or smaller than the predetermined value and the face is recognized, the videophone mode is maintained, and the distance is equal to or smaller than the predetermined value. If the face is not recognized and the brightness is greater than or equal to a predetermined value, the videophone mode is maintained, and if the distance is less than or equal to a predetermined value and the face is not recognized and the brightness is less than or equal to a predetermined value A portable terminal comprising control means for switching to the voice call mode.

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