Patent Publication Number: US-2013235081-A1

Title: Image processing apparatus, image processing method and recording medium

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2012-048911, filed on Mar. 6, 2012, the entire contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an image processing apparatus, an image processing method and a recording medium. 
     2. Description of Related Art 
     Heretofore, an electronic instrument has been known, which receives an orbit of an arbitrary shape, and moves and displays a predetermined character along the orbit concerned on a display unit (Japanese Patent Laid-Open Publication No. 2009-199622). 
     However, in the patent literature described above, an image of the predetermined character or the like has only been moved and displayed along the received orbit, and it has been difficult to enhance entertainment characteristics of a moving picture to be generated. 
     SUMMARY OF THE INVENTION 
     It is an object of the present to provide an image processing apparatus capable of enhancing the entertainment characteristics of the moving picture by changing a display style of an image on a foreground, and to provide an image processing method and a recording medium. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate presently preferred embodiments of the present invention and, together with the general description given above and the detailed description of the preferred embodiments given below, serve to explain the principles of the present invention in which: 
         FIG. 1  is a block diagram showing a schematic configuration of a portable terminal of one embodiment to which the present invention is applied; 
         FIG. 2  is a flowchart, showing an example of operations related to synthetic image generation processing by the portable terminal of  FIG. 1 ; 
         FIG. 3  is a flowchart showing an example of operations related to the image synthesis processing in the synthetic image generation processing of  FIG. 2 ; 
         FIG. 4  is a view schematically showing an example of a foreground image related to the synthetic image generation processing of  FIG. 2 ; 
         FIGS. 5A and 5B  are views schematically showing an example of a background image related to the synthetic image generation processing of  FIG. 2 ; and 
         FIGS. 6A to 6C  are views schematically showing an example of a synthetic moving picture related to the synthetic image generation processing of  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With regard to the present invention, a description is made below of a specific style thereof by using the drawings. However, the scope of the invention is not limited to the illustrated example. 
       FIG. 1  is a block diagram showing a schematic configuration of a portable terminal  100  of an embodiment to which the present invention is applied. 
     As shown in  FIG. 1 , the portable terminal  100  of this embodiment includes: a central control unit  1 ; a memory  2 ; a display unit  3 ; an operation input unit  4 ; an orbit specifying unit  5 ; an image processing unit  6 ; an image recording unit  7 ; a transceiver unit  8 ; and a communication control unit  9 . 
     Note that the portable terminal  100  is composed, for example, of an imaging device that is provided with a communication function, a mobile station for use in a mobile communication network of a cellular phone and a PHS (Personal Handy-phone System), a PDA (Personal Data Assistants), and the like. 
     The central control unit  1  is a unit that controls the respective units of the portable terminal  100 . Specifically, though not shown, the central control unit  1  includes a CPU (Central Processing Unit), a RAM (Random Access Memory), and a ROM (Read Only Memory), and performs a variety of control operations in accordance with a variety of processing programs (not shown) for the portable terminal  100 . 
     The memory  2  is composed, for example, of a DRAM (Dynamic Random Access Memory) and the like, and is a memory that temporarily stores data and the like, which are to be processed by the respective units such as the central control unit  1  and the image processing unit  6 . 
     The display unit  3  includes: a display panel  3   a ; and a display control unit  3   b.    
     The display panel  3   a  displays an image (for example, a background image P 2  and the like; refer to  FIG. 5A  and the like). Moreover, as the display panel  3   a , for example, a liquid crystal display panel, an organic EL display panel and the like are mentioned; however, these are merely examples, and the display panel  3   a  is not limited to these. 
     Based on image data with a predetermined size, which is read out from the image recording unit  7  and decoded by the image processing unit  6 , the display control unit  3   b  performs control to display a predetermined image on a display screen of the display panel  3   a . Specifically, the display control unit  3   b  includes a VRAM (Video Random Access Memory), a VRAM controller, a digital encoder, and the like. Then, the digital video encoder reads out a brightness signal Y and color difference signals Cb and Cr, which are decoded by the image processing unit  6  and stored in the VRAM (not shown), from the VRAM through the VRAM controller at a predetermined reproduction frame rate (for example, 10 fps), and based on these data, generates a video signal and outputs the generated video signal to the display unit  3 . 
     The operation control unit  4  is a unit that inputs a variety of instructions to a body of the portable terminal  100 . 
     Specifically, the operation input unit  4  includes: upper, lower, left and right cursor buttons and a decision button, which are related to selection instructions for a style, a function and the like; communication-related buttons related to execution instructions for sending/receiving of a telephone call, and the like; and a variety of buttons such as numeric buttons and symbol buttons, which are related to input instructions for text (any of the above is not shown). 
     Then, when the variety of buttons are operated by a user, the operation input unit  4  outputs operation instructions, which correspond to the operated buttons, to the central control unit  1 . The central control unit  1  allows the respective units to perform predetermined operations (for example, imaging of a subject, sending/receiving of a telephone call, transmission/reception of electronic mail, and the like) in accordance with the operation instructions outputted from the operation input unit  4  and inputted thereby. 
     Moreover, the operation input unit  4  includes a touch panel  4   a  provided integrally with the display panel  3   a  of the display unit  3 . 
     The touch panel  4   a  detects contact positions of a finger (hand) of the user, a touch pen and the like, which directly or indirectly contact the display screen that forms a display region of the display panel  3   a . That is to say, for example, the touch panel  4   a  is provided on the display screen or in an inside more than the display screen concerned, and detects XY coordinates of the contact positions on the display screen by a variety of methods such as a resistive film method, an ultrasonic surface elastic wave method, and an electrostatic capacitance method. Then, the touch panel  4   a  outputs position signals related to the XY coordinates of the contact positions. 
     Note that detection accuracy of the contact positions on the display screen by the touch panel  4   a  is changeable arbitrarily as appropriate, and for example, one pixel may be strictly set as the contact position, or a plurality of pixels within a predetermined range in which one pixel is taken as a center may be set as the contact position. 
     The orbit specifying unit  5  is a unit that specifies operation orbits L (refer to  FIG. 5B ) corresponding to predetermined rendering operations by the user. 
     That is to say, the orbit specifying unit  5  specifies at least two operation orbits L and L, which are rendered based on the predetermined operation for the operation input unit  4  by the user, on the display region of the display panel  3   a . Specifically, upon receiving the position signals related to the XY coordinates of the contact positions detected continuously by the touch panel  4   a  of the operation input unit  4 , the orbit specifying unit  5  specifies each of the contact positions of the touch panel  4   a  concerned as each of operation points on the display region of the display panel  3   a . Then, the orbit specifying unit  5  connects such a plurality of the specified operation points to one another, and thereby individually specifies the operation orbits L corresponding to the respective rendering operations by the user. 
     Note that the rendering of the respective operation orbits L, which uses the predetermined operation for the operation input unit  4 , may be performed in a state where the background image P 2  is displayed on the display region of the display panel  3   a . That is to say, as will be described later, a synthetic position of a foreground image P 1  in the background image P 2  is designated by using the operation orbits L, and accordingly, it becomes possible for the user to grasp a position where the foreground image P 1  is synthesized with and displayed in the background image P 2  displayed on the display region. 
     Moreover, the predetermined operation by the user for the operation input unit  4  related to the rendering of the respective operation orbits L may be, for example, an operation of rendering the plurality of operation orbits at substantially the same timing in such a manner of so-called multi-touch, or such an operation as rendering the respective operation orbits L at different timing while shifting a time axis. 
     Note that, in  FIG. 5B , an example of the two operation orbits L and L is schematically shown on the display region of the display panel  3   a ; however, it is possible to arbitrarily change as appropriate whether or not to display the operation orbits L so as to be visually recognizable. 
     Moreover, shapes and number of the respective operation orbits L are merely examples, are not limited to these described above, and are arbitrarily changeable as appropriate. Here, for example, in the case where three or more of the operation orbits L are specified, a configuration may be adopted, in which it is possible for the user to select desired two operation orbits L and L based on a predetermined operation for the operation input unit  4 . 
     The image processing unit  6  decodes such image data of a still image or a moving picture, which is related to a display target and read out from the image recording unit  7 , in accordance with a predetermined encoding method (for example, a JPEG format, a motion PEG format, an MPEG format and the like) corresponding thereto, and outputs the decoded image data to the display control unit  3   b . At this time, for example, the image processing unit  6  reduces the image data, which is read out from the image recording unit  7 , to a predetermined size (for example, a VGA or QVGA size) based on a display resolution of the display panel  3   a , and the like, and outputs the reduced image data to the display control unit  3   b.    
     Moreover, the image processing unit  6  includes: a first image obtaining unit  6   a ; a second image obtaining unit  6   b ; an image synthesis unit  6   c ; and a synthesis control unit  6   d.    
     Note that, for example, the respective units of the image processing unit  6  are composed of predetermined logic circuits; however, such a configuration concerned is merely an example, and the respective units of the image processing unit  6  are not limited to this. 
     The first image obtaining unit  6   a  obtains the foreground image P 1  for use in synthetic image generation processing (described later). 
     That is to say, the first image obtaining unit  6   a  obtains an image, which is desired by the user, as the foreground image P 1 . Specifically, among at least one of the foreground image P 1  recorded in the image recording unit  7 , the first image obtaining unit  6   a  obtains image data of the foreground image P 1  (refer to  FIG. 4 ), which is desired by the user and designated based on the predetermined operation for the operation input unit  4  by the user. 
     The second image obtaining unit  6   b  obtains the background image P 2  for use in the synthetic image generation processing. 
     That is to say, the second image obtaining unit  6   b  obtains an image, which is desired by the user, as the background image P 2  Specifically, among at least one of the background image P 2  recorded in the image recording unit  7 , the second image obtaining unit  6   b  obtains image data of the background image P 2  (refer to  FIG. 5A  and the like), which is desired by the user and designated based on the predetermined operation for the operation input unit  4  by the user. 
     The image synthesis unit  6   c  performs image synthesis processing for synthesizing the background image P 2  and the foreground image P 1  with each other. 
     That is to say, the image synthesis unit  6   c  synthesizes the foreground image P 1 , which is obtained by the first image obtaining unit  6   a , and the background image P 2 , which is obtained by the second image obtaining unit  6   b , with each other, and generates a synthetic image. Specifically, with regard to the respective pixels of the background image P 2 , the image synthesis unit  6   c  transmits pixels of the foreground image P 1 , which are pixels with an alpha value of 0, through the background image P 2  concerned, and with regard to pixels of the foreground image P 1 , which are pixels with an alpha value of 1, the image synthesis unit  6   c  overwrites the pixels of the background image P 2  by pixel values of the pixels of the foreground image P 1 , which correspond thereto. Moreover, among the respective pixels of the background image P 2 , with regard to pixels of the foreground image P 1 , which are pixels in which an alpha value is 0&lt;α&lt;1, the image synthesis unit  6   c  generates an image (background image×(1−α)), from which a subject region G of the foreground image P 1  is clipped out, by using a complement (1−α) of 1, thereafter calculates a value blended with a single background color in the event where the foreground image P 1  is generated by using the complement (1−α) of 1 in an alpha map, subtracts the value concerned from the foreground image P 1 , and synthesizes an obtained resultant with the image (background image×(1−α)) from which the subject region G is clipped out. 
     Moreover, in the case of generating the moving picture as the synthetic image, the image synthesis unit  6   c  performs the above-described respective pieces of processing for each of frame images which compose the moving picture. Note that the foreground image P 1  and the background image P 2 , which are used for the generation of the respective frame images, will be described later. 
     The synthesis control unit  6   d  controls a change of a display style of the foreground image P 1  to be synthesized with the background image P 2 . 
     That is to say, by taking, as references, the at least two operation orbits L and L specified by the orbit specifying unit  5 , the synthesis control unit  6   d  changes the display style of the foreground image P 1  (predetermined image), which is moved and displayed along the operation orbits L concerned, and in addition, is superimposed and displayed on the background image P 2 . Moreover, in the event of controlling the image synthesis processing by the image synthesis unit  6   c , and synthesizing the background image P 2  and the foreground image P 1  with each other by the image synthesis unit  6   c , the synthesis control unit  6   d  changes the display style of the foreground image P 1 . That is to say, the synthesis control unit  6   d  synthesizes each of a plurality of the foreground images P 1 , in which a synthetic position, size, orientation and the like of the subject region G are changed at a predetermined interval (for example, a distance interval, a time interval and the like), and the background image P 2  with each other by the image synthesis unit  6   c , and generates a synthetic moving picture M. 
     Specifically, the synthesis control unit  6   d  changes a synthetic position of the subject region G, which is to be superimposed and displayed on the background image  2 , at a predetermined pixel interval so as to move the subject region G of the foreground image P 1  along the two operation orbits L and L, which are specified by the orbit specifying unit  5 , along the operation orbits L concerned. 
     At this time, the synthesis control unit  6   d  may change the size of the subject region G of the foreground image P 1  in response to the interval between the two operation orbits L and l at the synthetic position of the foreground image P 1 . The change of the size of the subject region G is performed, for example, so that a ratio in number of pixels (size) between a horizontal direction (predetermined direction) of the subject region G and a vertical direction (direction perpendicular to the predetermined direction) thereof cannot be changed. Specifically, the synthesis control unit  6   d  resizes an image size of the foreground image P 1  (refer to  FIG. 4 ) so that, in the case where the number of pixels in the predetermined direction (for example, the horizontal direction and the like) of the subject region G is increased and decreased in response to the interval between the two operation orbits L and L at the synthetic position of the subject region G, the number of pixels in the direction (for example, the vertical direction and the like) perpendicular to the predetermined direction of the subject region G concerned can also be increased and decreased in response to a degree of the increase/decrease of the number of pixels in the predetermined direction concerned. Here, the number of pixels in each of the horizontal direction and vertical direction of the subject region G may include the number of pixels of a frame with a predetermined shape (for example, a rectangular shape), which surrounds the subject region G concerned. 
     Moreover, in response to an orientation of the two operation orbits L and L, the synthesis control unit  6   d  may change an orientation where the subject region G of the foreground image P 1  is synthesized. Specifically, the synthesis control unit  6   d  may change the orientation of the subject region G, for example, by setting a reference line (not shown) that passes through positions at an equal distance from the two operation orbits L and L between the respective operation orbits L concerned, and rotating the foreground image P 1  about a predetermined position of the subject region G, which is taken as a center (predetermined position), in a predetermined direction so that a reference line segment (not shown), which passes through the center of the subject region G concerned, can be substantially perpendicular to the reference line concerned. 
     Moreover, at a predetermined pixel interval, the synthesis control unit  6   d  may change the synthetic position of the subject region G, which is to be superimposed and displayed on the background image P 2 , so as to move a display position of the subject region G of the foreground image P 1  from a start point side in the event where any one operation orbit L between the two operation orbits L and L is rendered to an end point side therein. Here, the change of the synthetic position of the subject region G may be performed, for example, by taking, as a reference, a reference line (not shown) that passes through predetermined positions (for example, positions at an equal distance, and the like) between the two operation orbits L and L, or may be performed by taking at least either one of the operation orbits L as references. Moreover, in the case where lengths of the respective operation orbits L differ from each other, the change of the synthetic position of the subject region G may be performed so that ratios of the subject region G with respect to overall lengths of the respective operation orbits L can become equal to each other. 
     Note that the display position of the subject region G of the foreground image P 1  may be moved from the endpoint side in the event where any one operation orbit L is rendered to the start point side therein. 
     For example, in the case of moving and displaying the foreground image P 1  by every predetermined number of pixels in a predetermined direction (for example, an X-axis direction and the like) along the operation orbits L, the synthesis control unit  6   d  sets the synthetic position, size and orientation of the subject region G of the foreground image P 1  concerned so that the subject region G can be located between the two operation orbits Land L at a predetermined position on the start point side of either one operation orbit L between the two operation orbits L and L. Then, by the image synthesis unit  6   c , the subject region G of the foreground image P 1  is synthesized with the background image P 2 , and a first frame image F 1  is generated (refer to  FIG. 6A ). Thereafter, the synthesis control unit  6   d  sets the synthetic position, size and orientation of the subject region G of the foreground image P 1  concerned so that the subject region G can be located between the two operation orbits L and L at a position that has moved by a predetermined number of pixels to the endpoint side along the operation orbits L. Then, by the image synthesis unit  6   c , the subject region G of the foreground image P 1  is synthesized with the background image P 2 , and a second frame image F 2  is generated (refer to  FIG. 6B ). 
     The synthesis control unit  6   d  sequentially performs the above-described processing in a similar way also for third frame images and after (not shown), and finally, sets the synthetic position, size and orientation of the subject region G of the foreground image P 1  concerned so that the subject region G can be located between the two operation orbits L and L at a position on the end point side of the operation orbit L. Then, by the image synthesis unit  6   c , the subject region G of the foreground image P 1  is synthesized with the background image P 2 , and a final frame image Fn is generated (refer to  FIG. 6C ). 
     In such a way, as the synthetic images, the synthetic moving picture M composed of a plurality of frame images F. is generated. 
     The image recording unit  7  is composed, for example, of a non-volatile memory (flash memory) and the like. Moreover, the image recording unit  7  records image data of a variety of images (for example, the foreground image P 1 , the background image P 2 , and the like) encoded in accordance with the predetermined encoding method by an encoding unit (not shown) of the image processing unit  6 . 
     For example, the foreground image P 1  is a still image, and there is mentioned a still image of a subject-clipped image generated in subject clipping processing for extracting the subject region G (for example, a bird and the like) from a subject-present image in which a subject is present in a predetermined background (refer to  FIG. 4 ). Moreover, the image data of the foreground image P 1  is associated with an alpha map generated in the subject clipping processing. 
     Here, the alpha map is a map that, for each of the pixels of the foreground image P 1 , represents weight as an alpha value (0≦α≦1), the weight being in the event of performing alpha blending for the subject region G (refer to  FIG. 4 ) of the foreground image P 1  concerned with a predetermined background. 
     For example, the background image P 2  is a still image, and is an image to be displayed as the background of the foreground image P 1 . Moreover, the image data of the background image P 2  is encoded in accordance with a predetermined encoding method (for example, the JPEG format and the like). 
     Note that, for example, each of the foreground image P 1  and the background image P 2  may be a moving picture composed of a plurality of frame images. Specifically, as each of the foreground image P 1  and the background image P 2 , for example, there are mentioned: moving picture data composed of a plurality of continuous frame images imaged at a predetermined frame rate; continuously imaged image data imaged continuously at a predetermined shutter speed. 
     The transceiver unit  8  performs a telephone conversation with an external user of an external instrument connected to the portable terminal  100  through a communication network N. 
     Specifically, the transceiver unit  8  includes: a microphone  8   a ; a speaker  8   b ; a data conversion unit  8   c ; and the like. Then, the transceiver unit  8  performs A/D conversion processing for user&#39;s transmitted voice, which is inputted from the microphone  8   a , by the data conversion unit Sc, and outputs transmitted voice data to the central control unit  1 , and in addition, under control of the central control unit  1 , performs D/A conversion processing for voice data such as received voice data, which is outputted from the communication control unit  9 , and is inputted to the transceiver unit  8  concerned, by the data conversion unit  8   c , and outputs the processed voice data to the speaker  8   b.    
     The communication control unit  9  performs transmission/reception for data through the communication network N and a communication antenna  9   a.    
     That is to say, the communication antenna  9   a  is an antenna capable of data transmission/reception corresponding to a predetermined communication method (for example, the W-CDMA (Wideband Code Division Multiple Access) method, the CDMA 2000 method, the GSM (Global System for Mobile Communications) method and the like) which the portable terminal  100  concerned adopts in communication with a radio base station (not shown). Then, in accordance with communication protocol corresponding to the predetermined communication method, the communication control unit  9  performs the transmission/reception of the data through the communication antenna  9   a  with the radio base station by a communication channel set by this communication method. 
     That is to say, based on instruction signals to be outputted from the central control unit  1  and inputted to the communication control unit  9 , for the external instrument as a communication partner, the communication control unit  9  concerned performs transmission/reception of voice during the telephone conversation with the external user of the external instrument concerned, and the transmission/reception of the electronic mail therewith. 
     Note that the above-described configuration of the communication control unit  9  is merely an example, and the communication control unit  9  is not limited to this, and is changeable arbitrarily as appropriate. For example, though not shown, a configuration may be adopted, which is capable of accessing the communication network N through an access point (Access Point) by mounting a wireless LAN module thereon. 
     The communication network N connects the portable terminal  100  thereto through the radio base station, a gateway server (not shown) and the like. Moreover, the communication network N is a communication network constructed by using a private line or an existing general public line, and a variety of line forms such as a LAN (Local Area Network) and a WAN (Wide Area Network) are applicable thereto. 
     Moreover, for example, the communication network N includes: a variety of communication networks such as a telephone line network, an ISDN line network, a private line, a mobile communication network, a communication satellite line, and a CATV line network; the IP network; a VoIP (Voice over Internet Protocol) gateway; an Internet service provider; and the like. 
     Next, with reference to  FIG. 2  to  FIG. 6 , a description is made of the synthetic image generation processing by the portable terminal  100 . 
       FIG. 2  is a flowchart showing an example of operations related to the synthetic image generation processing. 
     The synthetic image generation processing, which will be described below, is processing to be executed in the case where an image synthesis style is selected and designated from among a plurality a plurality of operation styles, which are displayed on a menu screen, based on the predetermined operation for the operation input unit  4  by the user. 
     &lt;Synthetic Image Generation Processing&gt; 
     As shown in  FIG. 2 , first, the display control unit  3   b  displays a predetermined message, which instructs the designation of the background image P 2 , on the display screen of the display panel  3   a , and based on the predetermined operation for the operation input unit  4  by the user, the central control unit  1  determines whether or not the background image P 2  desired by the user is designated among at least one of the background images P 2  displayed on the display panel  3   a  (Step S 1 ). 
     Here, when it is determined that the desired background image P 2  (refer to  FIG. 5A  and the like) is designated (Step S 1 ; YES), then from among the at least one background image P 2  recorded in the image recording unit  7 , the second image obtaining unit  6   b  of the image processing unit  6  reads out and obtains the image data of the background image P 2 , which is desired by the user and is designated based on the predetermined operation for the operation input unit  4  by the user (Step S 2 ). 
     Note that, when it is determined in Step S 1  that the background image P 2  is not designated (Step S 1 ; NO), the central control unit  1  returns the processing to Step S 1 , and until it is determined that the background image P 2  is designated (Step S 1 ; YES), puts the processing on standby in a state where the predetermined message related to the designation of the background image P 2  is displayed on the display screen of the display panel  3   a.    
     Subsequently, within a predetermined period, the central control unit  1  determines whether or not there is an input instruction for the operation point on the display region of the display panel  3   a  by the user (Step S 3 ). Specifically, in response to whether or not the position signals related to the XY coordinates of the contact positions, which are outputted from the touch panel  4   a  in such a manner that the contact of the finger (hand) of the user, the touch pen and the like with the display screen of the display panel  3   a  is detected by the touch panel  4   a  concerned, are inputted, the central control unit  1  determines whether or not there is an input of the operation point by the user. 
     When it is determined in Step S 3  that there is no input of the operation point by the user (Step S 3  NO), the central control unit  1  returns the processing to Step S 3 , and repeatedly executes the above-described determination processing at predetermined timing (Step S 3 ). 
     Meanwhile, when it is determined in Step S 3  that there is an input of the operation point by the user (Step S 3 : YES), the orbit specifying unit  5  specifies the operation orbits L, which correspond to the respective rendering operations by the user, from the plurality of operation points (Step S 4 : refer to  FIG. 5B ). 
     Subsequently, the image processing unit  6  determines whether or not the two operation orbits L and L are specified by the orbit specifying unit  5  (Step S 5 ). 
     Here, when it is determined that the two operation orbits L and L are not specified by the orbit specifying unit  5  (Step S 5 ; NO), then the central control unit  1  returns the processing to Step S 3 , and receives a next input instruction for the operation point on the display region of the display panel  3   a.    
     Then, when it is determined that the two operation orbits L and L are specified by the orbit specifying unit  5  in Step S 5  (Step S 5 ; YES), the display control unit  3   b  displays a predetermined message, which instructs the designation of the foreground image P 1 , on the display screen of the display panel  3   a , and based on the predetermined operation for the operation input unit  4  by the user, the central control unit  1  determines whether or not the foreground image P 1  desired by the user is designated among the at least one of the foreground images P 1  displayed on the display panel  3   a  (Step S 6 ). 
     Here, when it is determined that the desired foreground image P 1  (refer to  FIG. 4 ) is designated (Step S 6 ; YES), then from among the at least one foreground image P 1  recorded in the image recording unit  7 , the first image obtaining unit  6   a  of the image processing unit  6  reads out and obtains the image data of the foreground image P 1 , which is desired by the user and is designated based on the predetermined operation for the operation input unit  4  by the user (Step S 7 ). 
     Note that, when it is determined in Step S 6  that the foreground image P 1  is not designated (Step S 6 ; NO), the central control unit  1  returns the processing to Step S 6 , and until it is determined that the foreground image P 1  is designated (Step S 6 ; YES), puts the processing  3  on standby in a state where the predetermined message related to the designation of the foreground image P 1  is displayed on the display screen of the display panel  3   a.    
     Next, based on the predetermined operation for the operation input unit  4  by the user, the central control unit  1  determines whether or not a start instruction for the synthesis between the background image P 2  and the foreground image P 1  is inputted (Step S 8 ). 
     Here, when it is determined that such a synthesis start instruction is not inputted (Step S 8 ; NO), the central control unit  1  returns the processing to Step S 8 , and puts the processing on standby until it is determined that the synthesis start operation is inputted (Step S 8 ; YES). 
     When it is determined in Step S 8  that the synthesis start instruction is inputted (Step S 8 ; YES), then under control of the synthesis control unit  6   d , the image synthesis unit  6   c  performs the image synthesis processing (refer to  FIG. 3 ) for synthesizing the background image P 2  and subject region G of the foreground image P 1  with each other (Step S 9 ). 
     Here, a description is made in detail of the image synthesis processing with reference to  FIG. 3 .  FIG. 3  is a flowchart showing an example of operations related to the image synthesis processing. 
     &lt;Image Synthesis Processing&gt; 
     As shown in  FIG. 3 , first, the synthesis control unit  6   d  designates “1” as a frame number of the first frame image F 1  serving as a processing target (Step S 21 ). 
     Subsequently, the image synthesis unit  6   c  reads out the alpha map stored in association with the foreground image P 1 , and expands the alpha map concerned to the memory  2  (Step S 22 ). 
     Next, the synthesis control unit  6   d  specifies a reference position, size and orientation for the synthesis of the subject region G of the foreground image P 1  in the background image P 2  (Step S 23 ). Specifically, for example, by taking, as references, shapes of the two operation orbits L and L specified by the orbit specifying unit  5 , the synthesis control unit  6   d  specifies the reference position for the synthesis so that the subject region G can individually contact one-side end portions (for example, right end portions) of the two operation orbits L and L concerned, and in addition, specifies the size and orientation of the subject region G so that the subject region G can be located between the two operation orbits L and L. 
     Note that, with regard to a region that goes out of a range of the alpha map by the fact that the alpha map is shifted with respect to the background image P 2  in the event where the synthetic position of the subject region G is decided in Step S 23 , α is set equal to 0, and a region where the alpha value is not present is allowed not to be present. 
     Subsequently, the image synthesis unit  6   c  designates any one pixel (for example, a pixel on an upper left corner portion) of the background image P 2  (Step S 24 ), and with regard to the pixel concerned, branches the processing based on the alpha value of the alpha map (Step S 25 ). Specifically, among any one pixel of the background image P 2 , with regard to a pixel in which an alpha value is 1 (Step S 25 ; α=1), the image synthesis unit  6   c  overwrites the pixel value of the background image P 2  by the pixel value of the pixel of the foreground image P 1 , which corresponds thereto (Step S 26 ). With regard to a pixel in which an alpha value is 0&lt;α&lt;1 (Step S 25 ; 0&lt;α&lt;1), the image synthesis unit  6   c  generates the image (background image×(1−α)) from which the subject region G is clipped out, by using the complement (1−α) of 1, thereafter calculates the value blended with the single background color in the event where the foreground image P 1  is generated by using the complement (1−α) of 1 in the alpha map, subtracts the value concerned from the foreground image P 1 , and synthesizes the obtained resultant with the image (background image×(1−α)) from which the subject region G is clipped out (Step S 27 ). With regard to a pixel in which an alpha value is 0, the image synthesis unit  6   c  (Step S 25 ; α=0), the image synthesis unit  6   c  allows transmission of the background image P 2  without doing anything. 
     Subsequently, the image synthesis unit  6   c  determines whether or not all of the pixels of the background image  6   c  are processed (Step S 28 ). 
     Here, when it is determined that all of the pixels are not processed (Step S 28 ; NO), the image synthesis unit  6   c  designates a next pixel as the processing target, moves the processing target to the pixel concerned (Step S 29 ), and shifts the processing to Step S 25 . 
     The above-described processing is repeated until it is determined that all of the pixels are processed in Step S 28  (Step S 28 ; YES), the image synthesis unit  6   c  generates the first frame image F 1  (refer to  FIG. 6A ) that composes the synthetic moving picture M in which the foreground image P 1  and the background image P 2  are synthesized with each other. 
     Then, when it is determined that all of the pixels are processed in Step S 28  (Step S 28 ; YES), the synthesis control unit  6   d  determines whether or not the synthetic position of the subject region G has reached end portions of the operation orbits L, which are on an opposite side to the reference position (Step S 30 ). 
     Here, when it is determined that the synthetic position of the subject region G has not reached the end portions of the operation orbits L (Step S 30 ; NO), then among the plurality of frame images F . . . which compose the synthetic moving picture M, the synthesis control unit  6   d  increases by one a frame number related to a next frame image (for example, the second frame image F 2 ) serving as the processing target, and designates the increased frame number (Step S 31 ). In such a way, the second frame image F 2  of the synthetic moving picture M becomes the processing target of the image synthesis processing. 
     Next, by taking the shapes of the two operation orbits L and L as references, the synthesis control unit  6   d  sets a synthetic position, size, orientation and the like of the subject region G in the second frame image F 2  of the synthetic moving picture M (Step S 32 ). Specifically, the synthesis control unit  6   d  sets the synthetic position, size and orientation of the subject region G of the foreground image P 1  concerned so that the subject region G can be located between the two operation orbits L and L at the position that has moved by the predetermined number of pixels to the endpoint side along the two operation orbits L and L. At this time, the synthesis control unit  6   d  corrects such a subject region portion (α=1) in the alpha map and such a portion (α=0) other than the subject region therein in response to the subject region G of the foreground image P 1 , in which the synthetic position, the size and the orientation are changed. 
     Next, the image synthesis unit  6   c  shifts the processing to Step S 24 , sequentially performs the respective pieces of processing of Steps S 25  to S 29 , for example, from the pixel on the upper left corner portion of the background image P 2 , and thereby generates the second frame image F 2  that composes the synthetic moving picture M in which the foreground image P 1  and the background image P 2  are synthesized with other. In such a way, by taking the shapes of the two operation orbits L and L as references, the second frame image F 2  (refer to  FIG. 6B ) is generated, in which the synthetic position, size, orientation and the like of the subject region G of the foreground image P 1  are changed. 
     Then, when it is determined that all of the pixels are subjected to the synthesis processing in Step S 29  (Step S 29 ; YES) by the fact that the generation of the second frame image F 2  is completed, the synthesis control unit  6   d  shifts the processing to Step S 30 , and in a similar way to the above, determines whether or not the synthetic position of the subject region G has reached the end portions of the operation orbits L, which are on the opposite side to the reference position (Step S 30 ). 
     Note that, in Step S 32 , in the case where the synthetic position that has moved by the predetermined number of pixels to the end point side along the two operation orbits L and L becomes a position that goes beyond the endpoints (end portions on the opposite side to the reference position of the operation orbits L, the synthetic position of the subject region G is set so that the subject region G can individually contact the endpoints of the two operation orbits L and L. In other words, in the final frame image Fn that composes the moving picture, a state is brought where the subject region G is in contact with the end portions of the operation orbits L on the opposite side to the reference position. 
     The above-described synthesis processing is repeated until it is determined that the synthetic position of the subject region G has reached the end portions of the operation orbits L in Step S 30  (Step S 30 ; YES), whereby the image synthesis unit  6   c  generates all of the frame images (refer to  FIG. 6A  to  FIG. 6C ) which compose the synthetic moving picture. 
     In such a way, the image synthesis processing is ended. 
     Next, as shown in  FIG. 2 , based on image data of the synthetic moving picture M composed of the plurality of frame images F . . . generated by the image generation unit  6   c , the display control unit  3   b  switches the respective frame images F . . . at the predetermined reproduction frame rate and displays the frame images F . . . on the display screen of the display panel  3   a , and thereby plays back and displays the synthetic moving picture M, in which the subject region G of the foreground image P 1  moves while changing the display style by taking the shapes of the two operation orbits L and L as references (Step S 10 ). 
     Thereafter, based on the predetermined operation for the operation input unit  4  by the user, the central control unit  1  determines whether or not an instruction to store the synthetic moving picture M in the image recording unit  7  is inputted (Step S 11 ). 
     Here, when it is determined that the instruction to store the synthetic moving picture M is inputted (Step S 11 ; YES), the central control unit  1  stores the image data of the synthetic moving picture M, which is composed of the plurality of frame images F . . . , in a predetermined recording region of the image recording unit  7  (Step S 12 ), and ends the synthetic image generation processing. 
     Meanwhile, in Step S 11 , when it is determined that the instruction to store the synthetic moving picture M is not inputted (Step S 11 ; NO), the central control unit  1  skips the processing of Step S 11 , and ends the synthetic image generation processing. 
     As described above, in accordance with the portable terminal  100  of this embodiment, the display style of the foreground image P 1 , which is to be moved and displayed along the two operation orbits L and L rendered based on the predetermined operation for the operation input unit  4  by the user and is to be superimposed and displayed on the background image P 2 , is changed by taking the shapes of the operation orbits L and L concerned as references. Accordingly, the synthetic moving picture M can be generated, in which the foreground image P 1  of which display style is changed in response to the change of the shapes of the two operation orbits L and L is superimposed on the background image P 2 . Hence, in comparison with a device that simply moves and displays the foreground image P 1  along the operation orbits L, entertainment characteristics of the synthetic moving picture M can be achieved. 
     Specifically, the size of the foreground image P 1  is changed in response to the interval between the two operation orbits L and L, and accordingly, the synthetic moving picture M can be generated, in which the subject region G of the foreground image P 1  is enlarged and reduced in response to the interval between the two operation orbits L and L concerned. 
     At this time, the size of the subject region G of the foreground image P 1  is changed so that the ratio in number of pixels (size) between the horizontal direction (predetermined direction) of the subject region G concerned and the vertical direction (direction perpendicular to the predetermined direction) thereof cannot be changed. In such a way, a feeling of wrongness in the event of enlarging and reducing the subject region C of the foreground image P 1  is reduced, and the synthetic moving picture M, which looks more natural, can be generated. 
     Moreover, the subject region G of the foreground image P 1 , which is to be moved and displayed along the two operation orbits L and L, is rotated so that the reference line segment, which passes through the predetermined position of the foreground image P 1 , can be substantially perpendicular to the reference line set between the operation orbits L concerned. In such a way, the change of the display style of the subject region G of the foreground image P 1  can be further diversified, and enhancement of the entertainment characteristics of the synthetic moving picture M can be achieved. 
     Moreover, the display position of the foreground image P 1  is moved from the start point side of either one operation orbit L between the two operation orbits L and L to the endpoint side thereof, and accordingly, the movement and display of the subject region G of the foreground image P 1 , which are along the operation orbits L, can be performed appropriately, whereby the generation of the synthetic moving picture M can be performed appropriately. 
     Furthermore, in the image synthesis processing for synthesizing the background image P 2  and the foreground image P 1  with each other, the display style of the foreground image P 1  is changed by taking the shapes of the at least two operation orbits L and L as references, and accordingly, only by performing the image synthesis processing, the synthetic moving picture M can be automatically generated, in which the display style of the foreground image P 1  is changed in accordance with the change of the shapes of the two operation orbits L and L. 
     Note that the present invention is not limited to the above-described embodiment, and may be subjected to varieties of improvements and design changes within the scope without departing from the spirit of the present invention. 
     For example, in the above-described embodiment, the portable terminal  100  is configured to change the display style of the foreground image P 1  in the event of synthesizing the foreground image P 1  concerned and the background image P 2  with each other by the image synthesis unit  6   c ; however, whether or not to include the image synthesis unit  6   c  is changeable arbitrarily as appropriate, and any configuration may be adopted as long as the configuration is one to change the display style of the subject region G of the foreground image P 1 , which is to be superimposed and displayed on the background image P 2 , in the event of moving and displaying the subject region G concerned along the two operation orbits L and L. 
     Moreover, in the above-described synthetic image generation processing, the synthetic moving picture M is stored in the image recording unit  7 ; however, whether or not to store the synthetic moving picture M concerned is changeable arbitrarily as appropriate, and a configuration in which the generated synthetic moving picture M is simply played back and displayed may be adopted. 
     Moreover, for example, in the case of applying a moving picture, which is composed of the plurality of frame images, as the foreground image P 1 , a moving speed and reproduction frame rate of the foreground image P 1  may be changed, for example, in consideration of the length, thickness and the like of the operation orbits L. 
     Moreover, the configuration of the portable terminal  100 , which is illustrated in the above-described embodiment, is merely an example, and the configuration of the portable terminal  100  according to the present invention is not limited to this. Furthermore, the portable terminal  100  is illustrated as the image processing apparatus; however, the image processing apparatus according to the present invention is not limited to this. 
     In addition, in the above-described embodiment, a configuration is adopted, in which functions as first obtaining means, specifying means and control means are realized in such a manner that the first image obtaining unit  6   a , the orbit specifying unit  5  and the synthesis control unit  6   d  are driven under the control of the central control unit  1 ; however, such a configuration to realize these functions is not limited to this, and a configuration may be adopted, in which these means are realized in such a manner that a predetermined program and the like are executed by the CPU of the central control unit  1 . 
     That is to say, in a program memory (not shown) that stores programs therein, a program that includes a first obtaining processing routine, a specifying processing routine, and a control processing routine is stored in advance. Then, by the first obtaining processing routine, the CPU of the central control unit  1  may be allowed to function as obtaining means for obtaining a predetermined image. Moreover, by the specifying processing routine, the CPU of the central control unit  1  may be allowed to function as means for specifying at least two orbits, which are rendered based on a predetermined operation for operation input means by the user, on a display region of display means. Furthermore, by the control processing routine, the CPU of the central control unit  1  may be allowed to function as means for changing a display style of the predetermined image, which is to be moved and displayed along the at least two orbits thus specified and is to be superimposed and displayed on the background image P 2  by taking shapes of the orbits concerned as references. 
     In a similar way, such a configuration may be adopted, in which second obtaining means and synthesis means are also realized in such a manner that a predetermined program and the like are executed by the CPU of the central control unit  1 . 
     Moreover, as computer-readable mediums which store therein the programs for executing the above-described respective pieces of processing, it is also possible to apply a non-volatile memory such as a flash memory, and a portable recording medium such as a CD-ROM as well as a ROM, a hard disk and the like. Moreover, as a medium that provides data of the programs through a predetermined communication line, a carrier wave is also applied. 
     Some of the embodiments of the present invention have been described; however, the scope of the present invention is not limited to the above-mentioned embodiments, and incorporates the scope of the invention, which is described in the scope of claims, and incorporates equilibrium ranges thereof.