JP4259363B2 - Video encoding device - Google Patents

Description

  The present invention relates to a moving image encoding apparatus, and can be applied to, for example, an apparatus that encodes a moving image input from a camera or the like provided in a mobile phone.

  For example, when video captured by a video camera or the like is transmitted using a communication line, a technique called encoding is generally used. Encoding is a process of compressing video (image) data, and intraframe encoding, interframe encoding, predictive encoding, and the like are known. In addition, a technique of appropriately selecting and using a method corresponding to the remaining amount of buffer among various encoding methods is generally known.

  In the technology as described above, it is required to perform encoding corresponding to the situation at each time and a control method peculiar to each system, but one type input from the outside for various encoding methods. In many cases, it is difficult to perform an appropriate response using only the control signal.

Here, when the injured people came out in the outdoors, consider contact the hospital by using a mobile phone, a case such as that using a moving picture tell the state of the injury at that time as an example. In this case, it is not necessary to give priority to the image quality when describing the situation at the time of the injury in words, but if you want to tell the state of the affected area of the injury clearly to the hospital, the image of the affected area is displayed in the hospital. It is extremely effective to transmit to. Therefore, in that case, it is required to take an image of the affected area with a video camera or the like and transmit the video signal to the hospital via the mobile phone. For example, when it is desired to first communicate the overall situation of the affected area, it is desirable to give the highest priority to the quality of moving images.

  Alternatively, in order to transmit the state of the affected area in more detail, it is often necessary to take an enlarged image of the affected area by using an optical zoom function of the camera.

  However, when the affected area image is zoomed in in this manner, the motion between frames becomes large, and the image quality may deteriorate.

  Therefore, in order to avoid such deterioration of the image quality of an enlarged image that often occurs during zoom-in, in the conventional technique, optical zoom control and selection of an encoding method in a video camera are linked. (Patent Document 1).

In other words, when zooming in, select a coding method that can restore a high-definition image by reducing the compression rate, and during zoom-out, increase the compression rate per frame to increase the number of frames. Is selected and performed so that priority can be given. Then, the image signal encoded by the optimum method in this way is transferred to a transmission destination such as a hospital via a mobile phone and its communication line as a transmission means.
JP-A-8-46857

  However, the optimum encoding method as described above can be selected in a video camera or the like having an optical zoom function. For example, an optical zoom function such as that used in a camera-equipped mobile phone is used. It cannot be applied to cameras that are not attached.

  In addition, when an optical zoom mechanism or the like is added to the camera of the camera-equipped mobile phone, the structure of at least that part becomes complicated, and as a result, the size and overall thickness of the mobile phone are significantly hindered. There is a problem that manufacturing costs and component costs may increase.

  Furthermore, even if such an optical zoom mechanism or the like can be added, there is another problem that it is difficult for a user who is unfamiliar with how to use the optical zoom function or the like. To do. For example, in the case of a camera-equipped mobile phone, processing such as zooming in on an image to be taken is generally performed electronically by operating an input operation button or the like, and optically I'm not going. For this reason, it is often unfamiliar for general users to operate optical functions such as optical zoom separately from operations such as input operation buttons. Various inconveniences may occur in terms of simplicity and ease of use.

  In addition, as a method of enlarging a captured image by a method other than using the optical zoom function in a camera-equipped mobile phone that does not have an optical zoom function, the captured image is expanded by signal processing. There is a method.

  However, when the image is enlarged by such signal processing, the definition of the image deteriorates. In addition, if an encoding process that increases the compression rate is performed on an image that has been enlarged by such signal processing and has deteriorated in definition, the definition of the image is further deteriorated.

  The present invention has been made to solve the above-described problem, and is an optimal encoding method corresponding to an image capturing state in an electronic apparatus or the like including a moving image capturing unit that does not have an optical zoom function. An object of the present invention is to provide a moving picture coding apparatus that can select and execute the above.

In order to solve such a problem, a moving image encoding apparatus according to the present invention selects a moving image signal input means for inputting a moving image signal and one of a plurality of predetermined encoding methods. In addition, according to the encoding method, the moving image encoding provided in the electronic apparatus including the moving image capturing unit that does not have the optical zoom function, and the encoding unit that encodes the input moving image signal. An image state detection unit that detects a state of an image reproduced by an input moving image signal, and a plurality of encoding methods corresponding to the image state detected by the image state detection unit select the encoding method, by the coding method, to encode the input moving image signal, e Bei a coding control means for controlling the encoding means, said image condition detection means is input The current image An image comparison unit that compares the previous image temporally before the current image, a previous image storage unit that stores the previous image, an image state storage unit that stores information on the determination result of the image state, and an image comparison unit And an image state determination unit that determines an image state based on the comparison result of the past and the past image state stored in the image state storage unit. The image state determination unit compares the current image with the previous image. If it is determined that the image has been enlarged, and if the current image is determined to be a still image after the enlargement has continued, the image signal is transmitted to the encoding control means. An instruction is given to select a coding method to be coded with priority .

  With such a configuration, an encoding method adapted to the state of the image represented by the input moving image signal is automatically selected, and the optimal moving image signal is encoded by the optimal encoding method.

  According to the moving image encoding apparatus of the present invention, an encoding method adapted to the state of the image represented by the input moving image signal is automatically selected, and the image state is adapted to the optimum encoding method. Since it is possible to encode an optimal moving image signal, whether it is in a zoomed-in state or a still-image state even in an electronic device (for example, a camera-equipped mobile phone) equipped with a moving image capturing means that does not have an optical zoom function. It is possible to select and execute an optimal encoding method for an image state such as a moving image state.

  Hereinafter, the best mode of a moving picture coding apparatus according to the present invention will be described with reference to the drawings.

(A) First Embodiment FIG. 1 is a block diagram illustrating a configuration of a main part of a video encoding device according to a first embodiment of the present invention.

  The moving image encoding apparatus includes an image state detection unit 100 that detects the state of input image data, a moving image signal input unit 101 that inputs image data from a camera device, and the like, and encodes the input image data. The main part is comprised from the moving image encoding part 102 which performs, and the encoding control part 103 which controls the encoding method of the input image data.

  More specifically, the image state detection unit 100 compares the input image data with the image data of the previous frame, the previous image storage unit 105 that stores the previous image data, and the input image. An image state determination unit 106 that determines the state of the image based on the comparison result between the data and the image data of the previous frame is provided.

  The moving image signal input unit 101 is connected to the image encoding unit 102 and the image comparison unit 104 and has a function of transmitting the input image data to the moving image encoding unit 102 and the image comparison unit 104. .

  The moving image encoding unit 102 is connected to the moving image signal input unit 101 and the encoding control unit 103, and the image data input from the moving image signal input unit 101 is encoded by the encoding control unit 103. And a function of outputting the encoded data.

  The image comparison unit 104 is connected to the moving image signal input unit 101, the previous image storage unit 105, and the image state determination unit 106, and is stored in the previous image storage unit 105 with the image data input from the moving image signal input unit 101. It has a function of comparing the image with the previous frame image and sending the result to the image state determination unit 106.

  The previous image storage unit 105 is connected to the image comparison unit 104 and has a function of storing the image data used as the image data of the current frame by the image comparison unit 104 as the previous frame image data for the next comparison. Have.

  The image state determination unit 106 is connected to the image comparison unit 104 and the encoding control unit 103, receives the processing result of the image comparison unit 104, determines the state of the image, and determines the encoding method based on the determination result. And has a function of transmitting a command for selecting it to the encoding control unit 103.

  The encoding control unit 103 is connected to the image state determination unit 106 and the moving image encoding unit 102, and selects an optimal encoding method based on a command output from the image state determination unit 106 in the image state detection unit 100. It has a function of performing control to select and cause the moving image encoding unit 102 to execute encoding processing according to the encoding method.

  Next, the operation of the moving picture coding apparatus according to the first embodiment will be described based on the flowchart of FIG.

  First, in step S101, a variable for counting the number of frames N is set to 0 (N = 0).

  Next, when there is image data input from the camera or the like through the moving image signal input unit 101 (YES in step S102), the image data is input to the image comparison unit 104 (step S103). If there is no input data (NO in step S102), the process ends (END).

  When the input image is the first frame (NO in step S104: N = 0), the image data is stored in the previous image storage unit 105 (step S105). Then, it waits for the next image data to be input (steps S105 to S102).

  On the other hand, if it is determined in step S104 that the image is the second frame or later (YES in step S104: N ≠ 0), after incrementing the frame number N by 1 (step S106), the previous The previous image stored in the image storage unit 105 is read, and the image comparison unit 104 compares the previous image with the currently input image (step S107).

  The result of the comparison in the image comparison unit 104 is input to the image state determination unit 106, and it is determined whether or not the state of the image at that time is a zoomed-in image state (step S108). If it is determined that the image is a zoomed-in image (YES in step S108), the encoding control unit 103 is instructed to select encoding that emphasizes image quality (step S109). A more detailed description of the comparison method and the determination method will be described later with reference to FIGS. On the other hand, if it is determined in step S108 that the image is not a zoomed-in image (NO in step S108), the encoding control unit 103 is instructed to select motion-oriented encoding (step S110). ).

  In any case, when the encoding method instruction is completed (step S109 or S110), the input image data is stored in the previous image storage unit 105 (step S105). Then, it waits for the next image data to be input (step S102).

  On the other hand, when the encoding control unit 103 is instructed to select an encoding method adapted to the state of the image, when it is an instruction to select an encoding method emphasizing image quality (in the case of step S109), Controls to select and execute a coding method that can reproduce (restore) higher-definition images, such as lowering the frame rate, lowering the compression rate per frame, and reducing the quantization step size. This is performed on the image encoding unit 102. Alternatively, in the case of an instruction to select a motion-oriented coding method (in the case of step S110), encoding such as increasing the frame rate, increasing the compression rate per frame, or increasing the quantization step size. Control for selecting and executing the method is performed on the moving image encoding unit 102.

  Then, the moving image coding unit 102 performs coding on the image data input from the moving image signal input unit 101 by the coding method selected by the coding control unit 103 and selected as the optimum one. Execute and output the encoded data.

  Next, the comparison method and determination method (operations mainly performed in steps S107 and S108) performed by the image comparison unit 104 and the image state determination unit 106 will be described in more detail with reference to FIGS.

  FIG. 3 shows an example of image data for three consecutive frames in a time series that is gradually zoomed in (also called zoom-up or close-up) from a normal so-called wide-angle image state. In FIG. 3, [0], [1], and [2] are assigned numbers in ascending order of frame numbers (in order from the previous image to the subsequent image).

  FIG. 4 is a flowchart showing the main flow of image comparison / determination processing. As a premise for explaining this flowchart, it is assumed that the image data of frame [0] (hereinafter referred to as [0]) is already stored in the previous image storage unit 105.

  After the counter C is set to 0 (step S401: C = 0), the image at the center of the screen as shown by the dotted line portion in the previous image shown in FIG. 3 (here, [0]) is cut out (step S402). ). Then, enlarged image data of the clipped image is created by a signal processing technique (step S403). This enlargement process may be performed using an enlargement filter, or image data enlarged simply at a predetermined magnification in the vertical and horizontal directions may be created.

  The image obtained by enlarging [0] is matched with the current image ([1] here) (step S404). As a result of the comparison, if the two match, for example, if the difference between the two is smaller than the specified value (YES in step S404), it is determined that the image is a zoomed-in image, and the encoding control unit 103 instructs the encoding control unit 103 to focus on image quality. A command for performing control to select and execute is output (step S405), and a series of processing ends (END). On the other hand, if the two do not match (NO in step S404), the counter C is incremented by 1 (step S406: for example, C = 0 is rewritten to C = 1).

  If the numerical value indicated by the counter C is not equal to or greater than the predetermined number of times (here α times) (NO in step S407: in other words, less than the predetermined number), the process returns to step S402, and again, Processing similar to the above (steps S401 to S407) is performed. However, in the next step S403, an enlarged image is created at an enlargement rate different from the above.

  Alternatively, when it is determined that the numerical value indicated by the counter C is equal to or greater than the predetermined number of times (YES in step S407), a command for selecting a motion-oriented coding method is output to the coding control unit 103. (Step S408), and a series of processing ends (END).

  The above processing is continued in the same manner as described above for the next image. That is, the same process as described above is performed on the next image [2] as the current image and the previous image [1] as the previous image. (Steps S401 to S404). If it is determined that the image [2] is a zoomed-in image (YES in step S404), control that places more importance on image quality than the image [1] that is the previous image is performed [2]. Is output to the encoding control unit 103 (step S405).

  Next, operations and effects of the moving picture coding apparatus according to the first embodiment will be described.

  If a moving image signal indicating that the subject is moving is input in the normal state (wide angle state) as shown in FIG. 3 as [0], it is detected (step S108). NO to step S110), by selecting and executing motion-oriented coding rather than image-oriented coding for each frame (for example, selecting and performing coding with a high frame rate) ), The movement of the object to be photographed can be reproduced smoothly.

  Alternatively, if a moving image signal in a zoom-in state as shown in [0] → [1] → [2] in FIG. 3 is input, it is detected (YES in step S108). In step S109, by selecting and executing encoding with emphasis on image quality for each frame rather than encoding with emphasis on motion (for example, by selecting and performing encoding with a small quantization step size). ), A high-definition moving image that can withstand a zoom-in state can be reproduced.

  As described above, according to the moving picture coding apparatus according to the first embodiment, even in a camera, electronic device, or the like that does not have an optical zoom function or is difficult to attach structurally, signal processing is performed. In addition to zooming in and out of the image, determining the state of the image at that time, selecting an encoding method that emphasizes image quality when zooming in, and selecting an encoding method that emphasizes motion otherwise Thus, it is possible to automatically select an appropriate encoding method in accordance with the state of the image and execute encoding that can always reproduce an image with good display quality.

(B) Second Embodiment FIG. 5 illustrates a configuration of a main part of a video encoding device according to a second embodiment. The moving image encoding apparatus includes an image state storage unit 501 that stores the state of an image in the image state detection unit 200, and a function that the image state determination unit 502 determines the state of the image and a still image. The point which is further provided with the function which discriminate | determines a state differs from 1st Embodiment. About others, it is the same as that of 1st Embodiment. In addition, the same code | symbol is attached | subjected to the component similar to 1st Embodiment, and the detailed description is abbreviate | omitted.

  The image state storage unit 501 is connected to the image state determination unit 502 and has a function of sequentially storing the image states determined by the image state determination unit 502 in time series.

  The image state determination unit 502 is connected to the image comparison unit 104, the image state storage unit 501, and the encoding control unit 103. After determining the image state based on the comparison result in the image comparison unit 104, It has a function of determining a stationary state as necessary and transmitting the result to the encoding control unit 103.

  Next, the operation of the moving picture coding apparatus according to the second embodiment will be described with reference to FIGS.

  First, a variable for counting the number N of frames is set to 0 (step S601: N = 0). Next, when there is image data input through the moving image signal input unit 101 from a camera (not shown) or the like (YES in step S602), the image data is input to the image comparison unit 104 (step S604). . At the same time, a variable Z that counts how many frames the zoom-in continues and a variable S that counts how many frames the stationary state continues are set to 0 (step S603). Thereafter, the variables S and Z are stored and updated in the image state storage unit 501. If there is no input data, the process ends (END).

  If there is image data and the input image is the first frame (when N = 0: NO in step 605), the image data is stored in the previous image storage unit 105 (step S606). Then, it waits for image data of the next frame to be input (steps S606 to S602).

  Alternatively, in the case of an image after the second frame (when N ≠ 0: YES in step S605), after incrementing the number of frames N (step S607), it is stored in the previous image storage unit 105. The image comparison unit 104 compares the image with the currently input image (step S608).

  The result of the comparison performed by the image comparison unit 104 is input to the image state determination unit 502, and it is determined whether the image is a zoomed-in image (step S609). If it is determined that the image is a zoomed-in image (YES in step S609), the variable Z is incremented, the variable S is set to 0 (step S610), and the process proceeds to step S606. In step S606, the input image data is stored in the previous image storage unit 105 and waits for the next image data to be input (step S602). Then, the above flow is repeated.

  Alternatively, if it is determined in step S609 that the image is not a zoomed-in image (NO in step S609), whether the zoomed-in image has continued in the past (Z> 0) or whether the stationary state has continued (S> 0). ) Is confirmed (step S611). In either case (YES in step S611), it is further determined whether or not the current image is in a state (still state) that is not significantly different from the previous image (step S612).

  If it is determined in step S612 that the vehicle is not stationary (NO in step S612), or if it is determined in step S611 that neither condition (Z> 0 or S> 0) is satisfied (step S612) In step S <b> 611, a command for performing control to select and execute a motion-oriented coding method is output to the coding control unit 103 (step S <b> 615).

  Alternatively, if it is determined in step S612 that the image is a still image (YES in step S612), the variable S is incremented and the variable Z is set to 0 (step S613), and image quality-oriented encoding is selected. Then, a command for performing the control to be executed is output to the encoding control unit 103 (step 614).

  Subsequently, the input image data is stored in the previous image storage unit 105 (step S606), and the next image data is waited for input (steps S606 to S602).

  On the other hand, when the encoding control unit 103 is instructed to select an encoding method, the encoding control unit 103 decreases the frame rate, decreases the frame compression rate, and the quantization step size when it is an instruction to select an encoding method emphasizing image quality. The moving image encoding unit 102 is controlled to select an encoding method such as reducing the image size and execute encoding based on the selected encoding method. Or, in the case of an instruction to select a motion-oriented coding method, select a coding method such as increasing the frame rate, increasing the frame compression rate, or increasing the quantization step size, and execute the encoding by that. The moving image encoding unit 102 is controlled.

  Then, the moving image encoding unit 102 encodes the image data input from the moving image input unit 101 by the encoding method controlled by the encoding control unit 103, and the encoded data is encoded. Output data.

  Next, an example of the comparison method and determination method performed by the image comparison unit 104 and the image state determination unit 502 will be described with reference to FIGS.

  FIG. 7 shows an example of image data for four frames continuous in time series. Numbers [0], [1], [2], and [3] are assigned in ascending order of frame numbers. The main flow of the comparison method and the determination method will be described using the almost right half of the flowchart shown in FIG. In addition, it is assumed that the image data [0] is already stored in the previous image storage unit 105.

  First, the previous frame image and the current frame image are compared (step S608). As a result, when it is determined that the image is a zoomed-in image, the variable Z is incremented (step S610). Here, for example, Z = 1. Further, in the case of [0] → [1] in FIG. 7, since the stationary state has not been detected yet, S = 0 is set (step S610). The method for determining whether or not this zoom-in is performed is the same as the method described in the first embodiment, and is therefore omitted here.

  If the next input image ([2] in FIG. 7) is also a zoomed-in image ([1] → [2] in FIG. 7; state Z = 2), this is determined, but the next input image ( In [2] → [3] in FIG. 7, it is determined that the image is not a zoom-in image.

  More specifically, in step S611, since variable Z> 0 (Z = 2), the process proceeds to step S612. In step S612, the previous image and the current image are compared. In this example, since the image is a still image, it is determined to be a still image (YES in step S612), and the process proceeds to step S613.

  In step S613, the variable S indicating the number of consecutive stationary states is incremented by 1 (here, S = 1), and in step S614, a command to select and execute image quality-oriented control is output to the encoding control unit 103. . The encoding control unit 103 that has received a control instruction emphasizing image quality transmits a control signal for selecting an encoding method, such as reducing the quantization step size, to the moving image encoding unit 102, so that the moving image encoding is performed. Based on the control signal, unit 102 performs encoding with emphasis on image quality so that a high-definition image adapted to a still image can be reproduced.

  As described above, according to the moving image encoding apparatus of the second embodiment, since the still image state is selected after the zoom-in state continues, the image quality-oriented encoding method is selected. Just moving the camera does not give priority to image quality, but if it is presumed that the camera has entered a still image after the target is placed on the target subject, an appropriate code for the image zoomed in and still An encoding method emphasizing image quality can be selected.

  More specifically, for example, when an injury is made outdoors, a phone with a camera is used to call the hospital, and the situation of the injury at that time is conveyed using moving images. When showing the condition, copy the affected area roughly (in a wide-angle image) and then zoom in gradually to the affected area. After reaching the maximum enlargement ratio, the affected area is photographed in the state of the enlarged still image for a while. There are times when the way of shooting is made, such as continuing. In such a case, it is possible to appropriately select and execute an encoding that can always reproduce a good image quality both during zooming in and still.

(C) Third Embodiment FIG. 8 illustrates a configuration of a main part of a video encoding device according to a third embodiment. This moving image encoding apparatus is different from the second embodiment in that it further includes a voice command detection unit 800 and a change command output unit 805. In addition, the same code | symbol is attached | subjected to the component similar to 2nd Embodiment, and the detailed description is abbreviate | omitted.

  The voice command detection unit 800 includes a voice input unit 801 that inputs voice during a call and a voice recognition unit 806.

  More specifically, the speech recognizing unit 806 selects a predetermined value from the speech-text converting unit 802 that converts speech input via the speech input unit 801 into text data, and the converted text data. A voice command determination unit 803 that identifies and extracts text data that matches a keyword and a keyword storage unit 804 that stores a predetermined keyword as text data constitute the main part.

  The voice input unit 801 is connected to the voice-text conversion unit 802 and has a function of transmitting voice during a call using the call function of the mobile phone to the voice-text conversion unit 802.

  The voice-text conversion unit 802 is connected to the voice input unit 801 and the voice command determination unit 803, converts voice data input from the voice input unit 801 into text data, and transmits the text data to the voice command determination unit 803. have.

  The voice command determination unit 803 is connected to the voice-text conversion unit 802, the keyword storage unit 804, and the change command output unit 805, and the keyword storage unit 804 is included in the text data obtained from the voice-text conversion unit 802. Has a function of identifying whether there is equivalent to text data stored in advance and sending the result to the change command output unit 805.

  The change command output unit 805 is connected to the moving image input unit 101, the voice command determination unit 803, and the image comparison unit 104, receives the determination result of the voice command determination unit 803, and turns on the switch based on the result. A switch having a function of turning off / off. When the switch of the change command output unit 805 is ON, the image data of the moving image input unit 101 is transmitted to the image comparison unit 104. Or when it is OFF, it is not transmitted.

  The other components, connection states, and functions are the same as those of the second embodiment, and thus detailed description thereof is omitted here.

  Next, main operations of the moving picture coding apparatus according to the third embodiment will be described with reference to FIGS. Since the main operation is substantially the same as that of the second embodiment, only different parts will be described here.

  A call is performed using the call function of the mobile phone. When the voice during the call is input to the voice input unit 801, the sound wave is captured and digitized to become voice data (step S901). .

  Subsequently, the voice-text conversion unit 802 converts the input voice data into text data (step S902). Here, the speech-to-text conversion means that speech data is converted into basic language units (phonemes), phonemes are constructed into words, and words that are pronounced similarly by judging the words from the context (for example, write). And right etc.).

  The converted text data is transmitted to the voice command determination unit 803, and matching with the text data stored in advance in the keyword storage unit 804 is performed (step S903).

  If the text data (keyword) stored in advance is matched, the voice command determination unit 803 instructs the change command output unit 805 to turn on the switch (step S904). Otherwise, an instruction to turn off the switch is issued (step S905), and the next voice input is awaited (step S901).

  In response to the instruction from the voice command determination unit 803, the change command output unit 805 turns the switch ON or OFF according to the instruction. When the switch is turned on, the image data obtained from the moving image input unit 101 is transmitted to the image comparison unit 104.

  Since the subsequent processing is the same as that of the second embodiment (step S906 and subsequent steps), detailed description thereof is omitted here.

  The above operation will be described with reference to a specific example. For example, it is assumed that text data such as “affected part”, “copy”, and “enlarge” is stored in advance in the keyword storage unit 804 as keywords.

  If the voice input to the voice input unit 801 is the word “I will copy the affected part from now on”, the voice data obtained by converting the voice into data is transmitted to the voice-text conversion unit 802 and converted into text data. Is done. When a word is extracted from the text data, for example, “from now on”, “affected part”, and “copy”. These text data and the keyword stored in the keyword storage unit 804 are matched, and when it is found that “affected part” and “copy” match, the switch of the change command output unit 805 is turned on. As shown in the second embodiment, the processing proceeds to adaptively changing the image encoding method.

  As described above, according to the third embodiment, since the voice during a call is used as a method for adaptively changing the image encoding method, the user's intention is automatically and effectively incorporated. It is possible to perform encoding with priority on image quality only when the user needs it.

(D) Fourth Embodiment FIG. 10 illustrates a configuration of a main part of a video encoding device according to a fourth embodiment. In this moving image encoding apparatus, the image state detection unit 300 includes an image storage unit 115 instead of the previous image storage unit 105, and an image similarity determination unit 116 instead of the image state determination unit 106. This is a different point from the first embodiment. In addition, the same code | symbol is attached | subjected to the component similar to 1st Embodiment, and the detailed description is abbreviate | omitted.

  The image storage unit 115 is connected to the image comparison unit 104, and has a function of storing sample image data in advance and providing it to the image comparison unit 104.

  The image similarity determination unit 116 is connected to the image comparison unit 104 and the encoding control unit 103. The image comparison unit 104 compares the input image data with the sample image data stored in advance. It has a function of receiving the result, determining the similarity of the images, and sending the result to the encoding control unit 103.

  Since components, connection states, and functions other than those described above are the same as those in the first embodiment, detailed descriptions thereof are omitted here.

  Next, the operation of this moving picture coding apparatus will be described with reference to FIG. Since the operation is substantially the same as that of the first embodiment, here, a different part from the moving picture encoding apparatus of the first embodiment will be particularly described.

  First, the image data input from the moving image input unit 101 is compared with the sample image data stored in the image storage unit 115 by the image comparison unit 104. As a comparison method at this time, for example, there is a method of using a matching method when determining whether or not the zoom-in is performed in the first embodiment. In addition, as a function to be added here, it is necessary to determine whether they are similar, not enlarged, so it is necessary to create a reduced image when matching is performed. It becomes.

  The result of comparison by the image comparison unit 104 is transmitted to the image similarity determination unit 116 for determination. For example, if the comparison calculation result (calculation value) of the image comparison unit 104 is lower than a predetermined threshold, it is determined that they are similar. The comparison result information is transmitted to the encoding control unit 103.

  If the result is similar, the encoding control unit 103 performs control to select and execute the image quality priority encoding method. If the result is not similar, the motion priority code Control to select and execute the system.

  Then, the moving image encoding unit 102 adapts to the state of the image at that time, such as a change of the quantization step size, by the encoding method designated (selected and controlled) by the encoding control unit 103. The encoded image data is output and the encoded image data is output.

  The above operation will be described using a specific example. For example, it is assumed that the image data input to the moving image input unit 101 is image data showing a foot injury. The image data is input to the image comparison unit 104 and compared with image data of another foot injury stored in advance in the image storage unit 115.

  The result of the comparison is transmitted to the image similarity determination unit 116. When the image similarity determination unit 116 determines that the comparison result is “similar” with a similarity equal to or higher than a predetermined similarity, that is, the input image is a foot injury, encoding control is performed. The image quality priority instruction is output to the unit 103, and a command is sent to the encoding control unit 103 so as to select an encoding method that can reproduce the state of injury as a more detailed and clear image.

  As described above, according to the moving image encoding apparatus according to the fourth embodiment, an image for which an image quality priority encoding method should be selected is stored in advance, and the image and an input image from a camera or the like are stored. Therefore, it is possible to automatically and accurately identify an image that requires image quality priority, and to efficiently perform image quality priority encoding control.

(E) Other Embodiments In each of the above-described embodiments, the case where the center portion of the screen is focused and the portion is enlarged has been described. However, the focused portion is designated as a specific area in the screen, Of course, it is possible to extract only a predetermined object from an image so as to focus only on the image.

  In the second embodiment, the determination that the image quality is given priority when the zoom-in continues for a predetermined number of times and subsequently becomes a still image is performed for a plurality of frames that are continuous in time series. However, the amount of calculation required for the determination may be reduced by making it every several frames or by thinning out the number of pixels.

  In the third embodiment, after speech-to-text conversion, matching with text prepared in advance is performed. For example, the user's own voice is stored as speech data, and matching is performed for each speech data. Anyway.

  In addition, the voice during a call is used for selecting an encoding method (as a judgment material) separately from the normal call function, but other voices may be used, for example, “image quality priority”. Of course, it is also possible to change the image encoding method according to the command by issuing the command in words.

  In addition, although the voice on the side that makes the call (us side) is used for selecting the encoding method, the voice from the other party that made the call to us may be used. For example, when the destination is a hospital, generally a voice (word) such as “Yes, XX hospital” is transmitted to us. Therefore, it is possible to change the image encoding method when the word “hospital” is detected from the speech from the other party.

In the fourth embodiment, when searching for images to be compared, if so infer the images to be samples from among the words describing the affected area, with the subsequent sample image and the input image It is further desirable since the comparison process is further greatly reduced.

It is a block diagram which shows the structure of the principal part of the moving image encoder which concerns on 1st Embodiment. It is a flowchart showing the flow of operation | movement of the moving image encoder which concerns on 1st Embodiment. It is a figure showing an example of the image data for 3 frames which time-sequentially zoomed in gradually. It is a flowchart which shows the main flows of the image comparison and determination process in the moving image encoder which concerns on 1st Embodiment. It is a figure showing the structure of the principal part of the moving image encoder which concerns on 2nd Embodiment. It is a flowchart which shows the main flows of the image comparison and determination process in the moving image encoder which concerns on 2nd Embodiment. It is a figure showing an example of image data for four frames which are time-sequentially continued to zoom in gradually and reach a still image state. It is a figure showing the structure of the principal part of the moving image encoder which concerns on 3rd Embodiment. It is a flowchart which shows the flow of main operation | movement of the moving image encoder which concerns on 3rd Embodiment. It is a figure showing the structure of the principal part of the moving image encoder which concerns on 4th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100, 200, 300 ... Image state detection part, 101 ... Moving image signal input part, 102 ... Moving image encoding part, 103 ... Encoding control part, 104 ... Image comparison part, 105 ... Previous image storage part, 106 ... Image State determination unit 115 ... Image storage unit 116 116 Image similarity determination unit 501 Image state storage unit 502 Image state determination unit 800 Voice command detection unit 801 Voice input unit 802 Voice-text Conversion unit, 803 ... voice command determination unit, 804 ... keyword storage unit, 805 ... change command output unit, 806 ... voice recognition unit.

Claims (8)

A moving image signal input unit for inputting a moving image signal and any one of a plurality of predetermined encoding methods are selected, and the input moving image signal is encoded by the encoding method. A moving image encoding device provided in an electronic apparatus including a moving image capturing unit that does not have an optical zoom function .
Image state detecting means for detecting the state of an image reproduced by the input moving image signal;
Corresponding to the image state detected by the image state detecting means, an encoding method is selected from the plurality of encoding methods, and the input moving image signal is encoded by the encoding method. as, example Bei a coding control means for controlling the encoding means,
The image state detection means includes: an image comparison unit that compares the input current image with a previous image temporally prior to the current image; a previous image storage unit that stores the previous image; An image state storage unit for storing determination result information; an image state determination unit for determining the image state based on a comparison result by the image comparison unit and a past image state stored in the image state storage unit; With
The image state determination unit determines that the current image is an enlarged image compared to the previous image, and the current image is a still state image after an enlarged state continues. If determined , the moving picture coding apparatus instructing the coding control means to select a coding method for coding the moving picture signal with priority on image quality .   In the case where the frame rate or the quantization step size or the compression rate per frame is the encoding method used for the previous image, the image state determination unit encodes the moving image signal with priority on image quality. The moving picture coding apparatus according to claim 1, wherein an instruction is given to select a coding method that reproduces a higher-definition image that is lower than that of the moving picture. Voice command detection means for detecting a predetermined keyword contained in the input voice and outputting a command for selecting an encoding method corresponding to the keyword;
A change command output means for outputting a command for changing the selection of the encoding method to the image state detection means in response to a command output from the voice command detection means. The moving image encoding device according to 1 or 2 . The voice command detection means converts the voice input unit to which the voice is input and the voice input to the voice input unit into character information, and selects character information that matches a predetermined keyword from the character information. The moving image encoding apparatus according to claim 3 , further comprising: a voice recognition unit that extracts and outputs a command for selecting an encoding method corresponding to the character information. The speech recognition unit includes: a speech-text conversion unit that outputs the speech as text information obtained by converting the speech data; a keyword storage unit that stores the predetermined keyword; and an output from the speech-text conversion unit. Compares the keyword stored in the keyword storage unit, extracts character information that matches the keyword from the character information, and outputs a command for selecting an encoding method corresponding to the character information The moving image encoding apparatus according to claim 4 , further comprising a voice command determination unit that performs the operation. The voice command detecting means outputs a command for selecting an encoding method corresponding to the character information when character information matching the predetermined keyword is detected, and the command is output. 6. The moving picture encoding apparatus according to claim 4 , wherein the encoding control means changes the selection of the encoding method only. The image state detection means includes an image storage unit that stores a sample image to be compared in advance, an image reproduced by the input moving image signal, and a sample image stored in the image storage unit. From the comparison result of the image comparison unit to be compared and the image comparison unit, the similarity to both compared images is determined. If the similarity is equal to or higher than the predetermined similarity, the encoding method corresponding to the sample image at that time moving image coding apparatus according to any one of claims 1 to 6, characterized in that an instruction to select and a image similarity determination unit that outputs to the encoding control means. A voice input unit for inputting voice and the voice input to the voice input unit are converted into character information, and character information that matches a predetermined keyword is extracted from the character information and corresponds to the character information. A speech recognition unit that outputs a command for selecting the encoded encoding method,
When the voice recognition unit extracts character information that matches the predetermined keyword, the image state detection unit selects an image corresponding to the keyword from the images stored in the image storage unit. The moving image coding apparatus according to claim 7 , wherein the moving image coding apparatus is used as the sample image that is searched and compared with the input image by the image comparison unit.

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