Patent Description:
For example, a video processing apparatus such as a driver monitor mounted in a vehicle is configured to store a video obtained by capturing a scene in the vehicle interior in a storage apparatus. The video processing apparatus stores a video capturing a scene in the vehicle interior, stores a video mainly capturing the driver, etc..

For example, patent literature <NUM> discloses an anti-blur camera configured to control the use of a strobe properly. The anti-blur camera detects the amount of blur of a camera by means of a blur amount detection unit and determines a shutter speed used when a strobe is not used based on the brightness of an object of shooting by means of a shutter speed determination unit. The anti-blur camera predicts the amount of blur at the shutter speed used when a strobe is not used determined by the shutter speed determination unit by means of a blur amount prediction unit. The anti-blur camera determines whether or not to use strobe lights based on the output of the blur amount prediction unit by means of a strobe lighting determination unit.

Patent Literature <NUM>: <CIT>
Attention is drawn to document <CIT> which relates to an eye opening degree determination unit which determines an eye opening degree of the eyes of an occupant by using an image captured by an image capturing unit that has an automatic exposure adjustment function. When the eye opening degree of the eyes is smaller than an eye opening degree threshold, an eye opening and closing determination unit determines that the eyes are closed. When the eyes are determined to be closed at the time when the automatic exposure adjustment function is valid, an exposure switching unit invalidates the automatic exposure adjustment function. A brightness detection unit detects the brightness of the surroundings of the eyes by using an image captured when the automatic exposure adjustment function is invalidated. When the eyes are determined to be closed, a drowsiness determination unit determines that the occupant is in a drowsy state if the brightness of the surroundings of the eyes is lower than a brightness threshold, and determines that the occupant is in an awakening state if the brightness is equal to or greater than the brightness threshold.

Further embodiments of the invention are defined by the appended dependent claims. The anti-blur camera disclosed in patent literature <NUM> properly controls emission or non-emission of strobe lights but is not configured to make the light emission intensity variable to increase or decrease while the strobe lights are being emitted. When the driver monitor irradiates the face of the driver of the vehicle with light such as infrared light at a constant light emission intensity to capture an image, the eyes of the driver will be loaded. We have become aware of the fact that, when the motion of the outline, etc. of the eyes is detected to analyze the state (e.g., how open or closed the eyes are) of the driver, etc. of a vehicle, the load on the eyes can be mitigated by changing light emission intensity.

Hereinafter, the invention will be described based on a preferred embodiment with reference to <FIG>. Identical or like constituting elements and members shown in the drawings are represented by identical symbols and a duplicate description will be omitted as appropriate. Those of the members that are not important in describing the embodiment are omitted from the drawings.

<FIG> is a block diagram showing a configuration of a video processing apparatus <NUM> according to the first embodiment. The video processing apparatus <NUM> is, for example, a driver monitor and is mounted in a vehicle to image a passenger in the vehicle interior continuously in time. The video processing apparatus <NUM> may record the video captured or discard the video without recording it. The video processing apparatus <NUM> is provided, for example, on the dashboard below the front window of the vehicle. The video processing apparatus <NUM> images, for example, the driver on board the vehicle as an object of shooting and recognizes the entirety of the face or a facial region such as the eyes in the object of shooting imaged.

The video processing apparatus <NUM> irradiates the face of the object of shooting with light such as infrared light for imaging so that the object of shooting can be recognized even in a dark scene at night or in a tunnel. Infrared light used for imaging is difficult for the vision of the driver, etc. to recognize, but the load on the eyes can be mitigated by suppressing the light emission intensity.

The video captured by the video processing apparatus <NUM> is used, for example, to identify the outlines of the left and right eyes to conduct an analysis related to portions of the eyes (e.g., how open or closed the eyes are, inclination of the left and right eyes, etc.). In this embodiment, a description of analysis function related to the state of a facial portion such as eyes is omitted. The video processing apparatus <NUM> may be provided with an analysis function related to how open or closed the eyes are, inclination of the left and right eyes, etc. An external apparatus may conduct an analysis of a facial portion based on the video collected or output by the video processing apparatus <NUM>. The analysis function for analyzing how open or closed the eyes are, inclination of the eyes, etc. is used for determination of the sleepiness or the emotional state (e.g., a normal state, a tense state, etc.) of the object of shooting.

The video processing apparatus <NUM> includes an imaging unit <NUM>, a light irradiation unit <NUM>, a recording unit <NUM>, a video processing unit <NUM>, an external input unit <NUM>, and an external output unit <NUM>, an image precision detection unit <NUM>, etc. The imaging unit <NUM> is, for example, a camera having a detector such as a CCD and images, for example, the driver on board the vehicle as an object of shooting. The imaging unit <NUM> acquires the video continuously in time and sends the acquired video to a video acquisition unit <NUM> described later.

The light irradiation unit <NUM> irradiates the object of shooting and, in particular, the facial portion, with light such as infrared light as appropriate so that the object of shooting such as the driver can be imaged even in the dark such as at night. The light emission intensity of light radiated from the light irradiation unit <NUM> is set by an imaging control unit <NUM> of the video processing unit <NUM> described later. It is preferred that the period of emission of light radiated by the light irradiation unit <NUM> concurs with the open period of the shutter, but there may be a slight time shift with respect to the open period of the shutter.

The recording unit <NUM> is, for example, a removable medium such as an SD card and a USB memory, or a hard disk, etc. The recording unit <NUM> shall be configured to record or delete the video acquired by the video acquisition unit <NUM>. Hereinafter, a configuration provided with the recording unit <NUM> will be described, but the recording unit <NUM> may not be provided in case the video processing apparatus <NUM> is not configured to have a part that records a video. The recording unit <NUM> may be removable from the video processing apparatus <NUM>. In this way, the recording unit <NUM> can be detached from the video processing apparatus <NUM> so that the video can be played back, etc. in a PC, etc..

The external input unit <NUM> acquires speed information, position information, etc. on the vehicle from an external apparatus. The external output unit <NUM> outputs video information, etc. processed by the video processing unit <NUM> to an external apparatus. The video processing apparatus <NUM> may append the speed information, the position information, etc. acquired by the external input unit <NUM> to the video and records the video or outputs the video outside.

The video processing unit <NUM> includes a video acquisition unit <NUM>, a video recognition unit <NUM>, a motion detection unit <NUM>, and an imaging control unit <NUM>. The video processing unit <NUM> is comprised of, for example, a CPU and performs the processes in the aforementioned units by operating in accordance with a computer program. A storage unit 30a is comprised of a data storage device such as a random access memory (RAM), a flash memory, and a hard disk recording device and stores the computer program etc. executed in the video processing unit <NUM>. Further, the storage unit 30a stores a dictionary for recognition for recognizing the face, eyes, etc. of the object of shooting in the video captured.

The video acquisition unit <NUM> acquires the video captured by the imaging unit <NUM>, subjects the video to a process such as data compression, and outputs the processed video to the recording unit <NUM>. The video acquisition unit <NUM> may be configured to include the imaging unit <NUM>. The open period of the shutter for imaging the object of shooting in the video acquisition unit <NUM> is set by the imaging control unit <NUM> described later. The frame rate of video frames is also set by the imaging control unit <NUM>.

The video recognition unit <NUM> recognizes the face or eyes of the object of shooting in the video input from the video acquisition unit <NUM>, based on the dictionary for recognition stored in the storage unit 30a. The recognition dictionary stored in the storage unit 30a includes shape data for the face, eyes, etc. The video recognition unit <NUM> recognizes the face, eyes, etc. by extracting a shape pattern presented in the video and checking the shape pattern against shape data included in the dictionary for recognition. The video recognition unit <NUM> can recognize the face, eyes, etc. in the video, by using a publicly known image recognition scheme that have been developed in various fields.

The motion detection unit <NUM> detects the motion of at least a portion of the face of the object of shooting and, in particular, detects the speed of motion. <FIG> are schematic diagrams showing an example of detection of motion by the motion detection unit <NUM>. The motion detection unit <NUM> detects, as shown in <FIG>, the blinking speed in an eye portion recognized by the video recognition unit <NUM> and outputs the speed to the imaging control unit <NUM>. The blink of eyes is produced by a motion in which the outline portions of the eyes move up and down moment by moment.

When the speed of blink of eyes is slow, the open state and the closed state of the eyes produced by the blink of eyes can be recognized even if the open period of the shutter in the video acquisition unit <NUM> is set to be long. Conversely, when the speed of blink of eyes is fast, the open state and the closed state of the eyes produced by the blink of eyes cannot be recognized if the open period of the shutter in the video acquisition unit <NUM> is long, and so it is therefore necessary to set the open period of the shutter to be short.

Further, the motion detection unit <NUM> detects, as shown in <FIG>, the speed of motion of line of sight in an eye portion recognized by the video recognition unit <NUM> and outputs the speed to the imaging control unit <NUM>. The motion of line of sight of the eyes is produced by a motion in which the pupil portions move left and right or up and down moment by moment.

When the speed of motion of line of sight is slow, image recognition in a video capturing the motion of line of sight is possible even if the open period of the shutter in the video acquisition unit <NUM> is set to be long. Further, when the speed of motion of line of sight is fast, it is necessary to set the open period of the shutter in the video acquisition unit <NUM> to be short.

Further, the motion detection unit <NUM> detects, as shown in <FIG>, the speed of swinging motion of the face as a whole by referring to the face as a whole recognized by the video recognition unit <NUM> and outputs the speed to the imaging control unit <NUM>. The swinging motion of the face is produced by a motion in which the outline of the face or a particular portion (e.g., the nose portion) moves left and right or up and down moment by moment.

When the speed of swinging motion of the face is slow, image recognition in a video capturing the swinging motion of the face is possible even if the open period of the shutter in the video acquisition unit <NUM> is set to be long. Further, when the speed of swinging motion of the face is fast, it is necessary to set the open period of the shutter in the video acquisition unit <NUM> to be short.

The imaging control unit <NUM> sets the open period of the shutter in the video acquisition unit <NUM> and the light emission intensity of the light irradiation unit <NUM> to change, based on the speed of motion of at least a portion of the face of the object of shooting detected by the motion detection unit <NUM>. <FIG> is a timing chart showing a case in which the open period of the shutter is set to be short, and <FIG> is a timing chart showing a case in which the open period of the shutter is set to be long.

When the speed of motion of at least a portion of the face of the object of shooting is fast, the open period of the shutter in the video acquisition unit <NUM> is set to a value L1 indicating a short period and sets the light emission intensity of the light irradiation unit <NUM> to a large value P2. The imaging control unit <NUM> defines a predetermined threshold value in advance for the speed of motion of at least a portion of the face of the object of shooting. When the speed of motion of at least a portion of the face input from the motion detection unit <NUM> is equal to or larger than the threshold value, the imaging control unit <NUM> determines that the speed of motion is fast. When the input speed is smaller than the threshold value, the imaging control unit <NUM> determines that the speed of motion is slow.

When the speed of motion of at least a portion of the face of the object of shooting is slow, the imaging control unit <NUM> sets the open period of the shutter in the video acquisition unit <NUM> to a value L2 (L2>L1) indicating a long period and sets the light emission intensity of the light irradiation unit <NUM> to a small value P1 (P1<P2). The imaging control unit <NUM> defines a predetermined threshold value in advance for the speed of motion of at least a portion of the face of the object of shooting. When the speed of motion of at least a portion of the face input from the motion detection unit <NUM> is equal to or larger than the threshold value, the imaging control unit <NUM> determines that the speed of motion is fast. When the input speed is smaller than the threshold value, the imaging control unit <NUM> determines that the speed of motion is slow. L1 and L2, which are open periods of the shutter, and P1 and P2, which are light emission intensity values, may be predefined by assuming a dark environment such as at night or assuming the speed of motion of the face of the object of shooting.

When the speed of motion of at least a portion of the face of the object of shooting is slow, the imaging control unit <NUM> sets the open period of the shutter in the video acquisition unit <NUM> to be longer and sets the light emission intensity of the light irradiation unit <NUM> to be smaller than those of the case in which the speed of motion is fast. Alternatively, the imaging control unit <NUM> may set the open period of the shutter and the light emission intensity to vary continuously in accordance with the speed of motion of at least a portion of the face of the object of shooting.

As described above, the motion of at least a portion of the face of the object of shooting is exemplified by the blink of eyes, the motion of line of sight, and the swinging motion of the face. The imaging control unit <NUM> sets the open period of the shutter and the light emission intensity to vary in accordance with these motions.

The image precision detection unit <NUM> detects the image recognition precision in the face of the object of shooting or in a facial portion such as the eyes and the nose and checks whether a sufficient image recognition precision is secured. The image recognition precision is a measure indicating whether it is possible to recognize a facial portion such as the eyes and the nose, the outline of the face, or the like in distinction from an adjacent portion. Specifically, the degree of image blur, etc. at a boundary portion is defined as an indicator.

Further, when an analysis is conducted to see how open or closed the eyes are, the inclination of the eyes, etc., the image precision detection unit <NUM> may check whether image precision is secured to a degree that enables analysis. When an analysis is conducted to see how open or closed the eyes are, the inclination of the eyes, etc., whether the brightness value in the white portion of the eye and in the pupil portion defines a difference that makes the portions distinguishable carries weight. The image precision may be defined based on a difference in brightness values between the portions. In other words, the image precision may be defined to be low when the difference in brightness value between the portions is small, and the image precision may be defined to be high when the difference in brightness value is large.

When the open period of the shutter is changed from a value representing a short period to a value representing a long period, for example, the imaging control unit <NUM> changes the setting of the open period of the shutter to a value representing a long period provided that the image recognition precision is better than a predetermined threshold value. When a sufficient image recognition precision cannot be secured after the imaging control unit <NUM> changes the setting of the open period of the shutter to a value representing a long period, the imaging control unit <NUM> returns the open period of the shutter to a value representing a short period. Similarly, when the light emission intensity is changed from a large value to a small value, for example, the imaging control unit <NUM> changes the setting of the light emission intensity to a small value provided that the image recognition precision is better than a predetermined threshold value. When a sufficient image recognition precision cannot be secured after the imaging control unit <NUM> changes the setting of the light emission intensity to a small value, the imaging control unit <NUM> returns the light emission intensity to a large value.

Further, in changing the setting of the open period of the shutter to a value representing a long period, the imaging control unit <NUM> may gradually change the setting of the shutter open period from a value representing a short period to a value representing a long period, checking that the image recognition precision detected by the image precision detection unit <NUM> is proper. Similarly, in changing the setting of the light emission intensity to a small value, the imaging control unit <NUM> may gradually change the setting of the light emission intensity from a large value to a small value, checking that the image recognition precision detected by the image precision detection unit <NUM> is proper.

A description will now be given of the operation of the video processing apparatus <NUM>, based on the process of changing the shutter and the light emission intensity. <FIG> is a flowchart showing a sequence of steps for changing the shutter and the light emission intensity performed in the video processing apparatus <NUM>. The light irradiation unit <NUM> of the video processing apparatus <NUM> starts irradiating the object of shooting with light (S1) and acquires the video of the object of shooting captured by the imaging unit <NUM> by means of the video acquisition unit <NUM> (S2). The video recognition unit <NUM> recognizes at least a portion of the face of the object of shooting in the image, and the motion detection unit <NUM> detects the speed of motion of the recognized portion (S3).

The imaging control unit <NUM> determines whether the speed of motion detected by the motion detection unit <NUM> is equal to or larger than a predetermined threshold value (S4). When the imaging control unit <NUM> determines that the speed of motion of at least a portion of the face of the object of shooting is equal to or larger than the predetermined threshold value (S4: YES), the imaging control unit <NUM> sets the open period of the shutter in the video acquisition unit <NUM> to a value representing a short period, sets the light emission intensity of the light irradiation unit <NUM> to a large value (S5), and terminates the process. It should be noted that, when the open period of the shutter is set to be short and the light emission intensity is set to a large value prior to the determination in step S4, the imaging control unit <NUM> maintains the setting.

When the imaging control unit <NUM> determines that the speed of motion of at least a portion of the face of the object of shooting is less than the threshold value in step S4 (S4: NO), the imaging control unit <NUM> sets the open period of the shutter in the video acquisition unit <NUM> to a value representing long period, sets the light emission intensity of the light irradiation unit <NUM> to a small value (S6), and terminates the process.

Further, when the image recognition precision detected by the image precision detection unit <NUM> in the video acquired after step S6 drops, the imaging control unit <NUM> may change the setting to set the open period of the shutter to a value representing a short period and set the light emission intensity of the light irradiation unit <NUM> to a large value. Alternatively, as described above, the imaging control unit <NUM> may set the open period of the shutter and the light emission intensity to vary continuously in accordance with the speed of motion of at least a portion of the face of the object of shooting.

When the speed of motion of at least a portion of the face of the object of shooting is slower than the predetermined threshold value, the video processing apparatus <NUM> sets the open period of the shutter in the video acquisition unit <NUM> to a value representing a long period and sets the light emission intensity of the light irradiation unit <NUM> to a small value. The video processing apparatus <NUM> can mitigate the load on the eyes of the object of shooting by setting the light emission intensity to a small value and can obtain a bright video by irradiating the object of shooting with a light mount necessary for imaging by setting the open period of the shutter to a value representing a long period.

When the speed of motion of at least a portion of the face of the object of shooting is faster than the predetermined threshold value, the video processing apparatus <NUM> sets the open period of the shutter in the video acquisition unit <NUM> to a value representing a short period and sets the light emission intensity of the light irradiation unit 11to a large value. The video processing apparatus <NUM> can suppress reduction in the image recognition precision when the motion of at least a portion of the face of the object of shooting is fast, by setting the open period of the shutter to a value representing a short period, and can acquire a bright video by setting the light emission intensity to a large value.

The video processing apparatus <NUM> detects, as motion of at least a portion of the face of the object of shooting, the blink of eyes, the motion of line of sight, the swinging motion of the face, or the like, by means of the motion detection unit <NUM>. A video of an open state and a closed state of the eyes can be acquired properly by changing the open period of the shutter and the light emission intensity in accordance with the speed of the blink of eyes in the object of shooting.

Further, a video capturing the motion of line of sight can be acquired properly by changing the open period of the shutter and the light emission intensity in accordance with the speed of motion of line of sight. Similarly, it is possible to ensure that a video capturing the direction (leftward, rightward, upward, downward) in which the object of shooting faces is captured by changing the open period of the shutter and the light emission intensity in accordance with the speed of swinging motion of the face.

<FIG> is a block diagram showing a configuration of a video processing apparatus according to the second embodiment. The video processing apparatus <NUM> according to the second embodiment further includes a blur amount detection unit <NUM> in addition to the features in embodiment <NUM>. The blur amount detection unit <NUM> detects the amount of blur in the video of the object of shooting produced by a vibration or the like of the vehicle in which the video processing apparatus <NUM> is mounted by, for example, referring to doubled images or blur in an edge portion in the video acquired by the video acquisition unit <NUM>.

The imaging control unit <NUM> sets the open period of the shutter to be short and the light emission intensity to be large when the blur amount detected by the blur amount detection unit <NUM> is large. Further, the imaging control unit <NUM> sets the open period of the shutter to be long and the light emission intensity to be small when the blur amount is small.

In the embodiments described above, an example is shown in which the open period of the shutter and the light emission intensity are made variable without changing the frame rate of the video, but the frame rate of the video may also be changed. When the speed of motion of at least a portion of the face of the object of shooting is slow and the blur amount is small, the imaging control unit <NUM> may lower the frame rate of the video acquired by the video acquisition unit <NUM> within a range in which the image recognition precision for analyzing how open or closed the eyes are, the inclination of the eyes, etc. is sufficiently secured.

The video processing apparatus <NUM> can further mitigate the load on the eyes of the object of shooting by lowering the frame rate of the video acquired and setting the open period of the shutter to be long and the light emission intensity to be small by means of the imaging control unit <NUM>.

In the embodiments described above, an example is shown of detecting, as motion of at least a portion of the face of the object of shooting, the blink of eyes, the motion of line of sight, the swinging motion of the face, or the like, by means of the motion detection unit <NUM>, but the motion of the mouth, the noise, etc. may be detected. Further, the motion detection unit <NUM> may detect, as motion of at least a portion of the face of the object of shooting, one or a plurality of motions including the blink of eyes, the motion of line of sight, etc. The imaging control unit <NUM> may change the open period of the shutter and the light emission intensity based on the speed of one or a plurality of motions.

Further, the imaging control unit <NUM> may set the light emission intensity of the light irradiation unit <NUM> to <NUM> when the outside light irradiating the object of shooting is intense and the light amount is sufficiently secured. The imaging control unit <NUM> may set the open period of the shutter to be short to increase the image recognition precision, provided the light amount is more than enough. The video processing apparatus <NUM> further includes an open/closed eye detection unit (not shown) that detects an open state and a closed state of the eyes in the video. When the eyes are closed, the video processing apparatus <NUM> gives priority to image recognition precision and set the open period of the shutter to be short and the light emission intensity to be large.

Further, the video processing apparatus <NUM> may sense sunglasses etc. that cut the wavelength range of the light source used in the light irradiation unit <NUM> and sets the open period of the shutter to be short and light emission intensity to be large when the object of shooting is wearing sunglasses that meet the condition, giving priority to image recognition precision.

A description will now be given of the features of the video processing apparatus <NUM>, the video processing method, and the video processing program according to the embodiments and the variation described above. The video processing apparatus <NUM> includes the light irradiation unit <NUM>, the video acquisition unit <NUM>, the motion detection unit <NUM>, and the imaging control unit <NUM>. The light irradiation unit <NUM> irradiates the face of an object of shooting with light. The video acquisition unit <NUM> acquires a video capturing the face of the object of shooting. The motion detection unit <NUM> detects the speed of motion of at least a portion of the face in the video acquired by the video acquisition unit <NUM>. When the speed detected by the motion detection unit <NUM> is slower than a predetermined threshold value, the imaging control unit sets the open period of the shutter in the video acquisition unit <NUM> to be long and the light emission intensity of the light irradiation unit <NUM> to be small. When the speed is faster than the predetermined threshold value, the imaging control unit <NUM> sets the open period of the shutter in the video acquisition unit <NUM> to be short and the light emission intensity of the light irradiation unit <NUM> to be large.

Further, the motion detection unit <NUM> detects the speed of blink in the eye portion in the video. This allows the video processing apparatus <NUM> to change the open period of shutter and the light emission intensity in accordance with the speed of blink of eyes and acquire a video of an open state and a closed state of the eyes properly.

Further, the motion detection unit <NUM> detects the speed of motion of line of sight in the video. This allows the video processing apparatus <NUM> to change the open period of the shutter and the light emission intensity in accordance with the speed of motion of line of sight and properly acquire a video capturing the motion of line of sight.

Further, the motion detection unit <NUM> detects the speed of motion of swinging motion of the face in the video. This allows the video processing apparatus <NUM> to ensure that a video capturing the direction (leftward, rightward, upward, downward) in which the object of shooting faces is acquired by changing the open period of the shutter and the light emission intensity in accordance with the speed of swinging motion of the face.

The video processing apparatus <NUM> further includes the blur amount detection unit <NUM> for detecting the blur amount of the object of shooting. The imaging control unit <NUM> changes the open period of the shutter and the light emission intensity in accordance with the blur amount detected by the blur amount detection unit <NUM>. This allows the video processing apparatus <NUM> to mitigate the load on the eyes of the object of shooting while suppressing reduction in the image recognition precision at the same time.

Further, the video processing apparatus <NUM> changes the frame rate of the video acquired by the video acquisition unit <NUM> based on the speed detected by the motion detection unit <NUM>. This allows the video processing apparatus <NUM> to mitigate the load on the eyes by lowering the frame rate of the video acquired and, further, setting the open period of the shutter to be long and the light emission intensity to be small.

The video processing method includes a light irradiation step, a video acquisition step, a motion detection step, and an imaging control step. The light irradiation step irradiates the face of an object of shooting with light. The video acquisition step acquires a vide capturing the face of the object of shooting. The motion detection step detects a speed of motion of at least a portion of the face in the video acquired by the video acquisition step. When the speed of motion by the motion detection step is slower than a predetermined threshold value, the imaging control step sets the open period of the shutter in the video acquisition step to be long and light emission intensity in the light irradiation step to be small. When the speed is faster than the predetermined threshold value, the imaging control step sets the open period of the shutter in the video acquisition step to be short and the light emission intensity in the light irradiation step to be large. According to this video processing method, it is possible to set the light emission intensity to a small value to mitigate the load on the eyes of the object of shooting irradiated with light.

The video processing program causes a computer to execute a light irradiation step, a video acquisition step, a motion detection step, and an imaging control step. The light irradiation step irradiates the face of an object of shooting with light. The video acquisition step acquires a vide capturing the face of the object of shooting. The motion detection step detects a speed of motion of at least a portion of the face in the video acquired by the video acquisition step. When the speed detected by the motion detection step is slower than a predetermined threshold value, the imaging control step sets the open period of the shutter in the video acquisition step to be long and light emission intensity in the light irradiation step to be small. When the speed is faster than the predetermined threshold value, the imaging control step sets the open period of the shutter in the video acquisition step to be short and the light emission intensity in the light irradiation step to be large. According to this video processing program, it is possible to set the light emission intensity to a small value to mitigate the load on the eyes of the object of shooting irradiated with light.

Claim 1:
A video processing apparatus (<NUM>) comprising:
a light irradiation unit (<NUM>) that irradiates a face of an object of shooting with light;
a video acquisition unit (<NUM>) that acquires a video capturing the face of the object of shooting;
a motion detection unit (<NUM>) that detects a speed of motion of at least a portion of the face in the video acquired by the video acquisition unit (<NUM>);
an open/closed eye detection unit that detects an open state and a closed state of eyes in the video acquired by the video acquisition unit (<NUM>); and
an imaging control unit (<NUM>) that changes an open period of a shutter in the video acquisition unit (<NUM>) and a light emission intensity of the light irradiation unit (<NUM>),
wherein
the imaging control unit (<NUM>) changes the open period of the shutter to be long and the light emission intensity to be small when the speed of motion detected by the motion detection unit (<NUM>) is slower than a predetermined threshold value, and changes the open period of the shutter to be short and the light emission intensity to be large when the speed of motion detected by the motion detection unit (<NUM>) is faster than the predetermined threshold value,
wherein
the imaging control unit (<NUM>) changes the open period of the shutter to be short and the light emission intensity to be large when the open/closed eye detection unit detects the closed state of eyes to give priority to image recognition precision.