IMAGE DISPLAY DEVICE, IMAGE LIST DISPLAY METHOD, AND IMAGE LIST DISPLAY PROGRAM

Abstract

To display an image list stored in a memory with good visibility and to display the image list at a high speed, an image display device reads an image file in an Exif format, extracts a thumbnail image included in the image file in the Exif format, and generates a displayed image having a predetermined size and a square shape, thus displaying it in the image list. It is possible to improve visibility in displaying the image file aligning square-shaped displayed image having the same size while precluding blanks. It is possible to perform high-speed processing in producing an image list using thumbnail images included in image files in the Exif format.

Claims

1. An image display device comprising: a display; and a controller configured to input a plurality of thumbnail images having effective image areas each having a same aspect ratio as each main image within a plurality of main images having different aspect ratios and to thereby generate a plurality of display images each having a same size based on a short side of each effective image area of each thumbnail image, thus controlling the display to display the plurality of display images.

2. The image display device according to claim 1, wherein the controller generates the plurality of display images each including all pixels aligned in a center of each effective image area of each thumbnail image in correspondence with pixels aligned along the short side of each effective image area with respect to the plurality of thumbnail images.

3. The image display device according to claim 2, wherein the controller generates a plurality of resized images by changing a size of each thumbnail image while maintaining its aspect ratio such that the short side of each effective image area matches each side of each display image having a predetermined side, and wherein the controller extracts the plurality of display images from the plurality of resized images such that each display image is extracted about a center of gravity of each resized image.

4. The image display device according to claim 2, wherein the controller extracts a square image about a center of each thumbnail image such that the square image includes all the pixels aligned in the center of each effective image area in correspondence with the pixels aligned along the short side of each effective image area of each thumbnail image, and wherein the controller changes a size of the square image to match the size of each display image.

5. An image display method comprising: inputting a plurality of thumbnail images having effective image areas each having a same aspect ratio as each main image within a plurality of main images having different aspect ratios; generating a plurality of display images each having a same size based on a short side of each effective image area of each thumbnail image; and displaying the plurality of display images on a display.

6. A non-transitory computer-readable storage medium having stored therein a computer program causing a computer to implement the image display method according to claim 5.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0021] FIG. 1 A block diagram showing an image display device according to a first embodiment of the present invention.

[0022] FIG. 2 An illustration for a data configuration of an image file in an Exif format used in the first embodiment of the present invention.

[0023] FIG. 3 A flowchart showing a process of producing a list of square-shaped images displayed according to the first embodiment of the present invention.

[0024] FIG. 4 Explanatory illustrations for a process of producing a list of square-shaped images displayed according to the first embodiment of the present invention.

[0025] FIG. 5 An explanatory illustration for a process of producing a list of square-shaped images displayed according to the first embodiment of the present invention.

[0026] FIG. 6 An explanatory illustration for a list of images displayed according to the first embodiment of the present invention.

[0027] FIG. 7 A flowchart showing a process of producing a list of square-shaped images displayed according to a second embodiment of the present invention.

[0028] FIG. 8 Explanatory illustrations for a process of producing a list of square-shaped images displayed according to the second embodiment of the present invention.

[0029] FIG. 9 Illustrations for conventional examples of thumbnail images with blanks occurring in an image file in the Exif format.

[0030] FIG. 10 Illustrations for other conventional examples of thumbnail images with blanks occurring in an image file in the Exif format.

[0031] FIG. 11 Illustrations for a conventional list of images displayed in different aspect ratios.

DESCRIPTION OF EMBODIMENTS

[0032] Hereinafter, embodiments of the present invention will be described with reference to drawings.

First Embodiment

[0033] FIG. 1 is a block diagram showing the configuration of a mobile phone 1 equipped with a camera, which is an image display device according to the first embodiment of the present invention. As shown in FIG. 1, the mobile phone 1 with a camera includes an image device 21, a controller 22, a built-in antenna 23, a wireless communication part 24, a signal processor 25, a speaker 27, a microphone 28, an audio processor 29, a memory 30, a display 31, and various keys 32.

[0034] As the image device 21, it is possible to use a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary MOS) image sensor. A subject image shot with the image device 21 is digitized, subjected to compressive coding according to the JPEG (Joint Photographic Experts Group) scheme under control of the controller 22, and then stored in the memory 30 as an image file in the Exif format.

[0035] The controller 22 is configured of a CPU (Central Processing Unit) to control the entirety of a device. The controller 22 is associated with the memory 30 and the display 31. As described above, the memory 30 stores image data shot with the image device 21 as well as various types of data such as telephone directory data and mail data. As the memory 30, it is possible to use a card-type flash memory other than a built-in memory.

[0036] For example, the display 31 is a liquid crystal display. The display 31 shows various types of characters and images. Additionally, the display 31 may serve as a view finder to shoot an image with the image device 21. The display 31 may show a screen reproducing image data stored in the memory 30. Moreover, the first embodiment of the present invention allows the display 31 to show a list of images stored in the memory 30. At this time, the first embodiment of the present invention shows an image list aligning square-shaped images with the same size.

[0037] In order to display an image list aligning square-shaped images having the same size stored in the memory 30, as described above, the first embodiment of the present invention includes an image file extraction part 51 and a square-image generation part 52 which are implemented in the controller 22 executing predetermined programs. The image file extraction part 51 reads an image file in the Exif format from the memory 30, thus extracting thumbnail images included in the read image file. The square-shaped image generation part 52 generates square-shaped images based on thumbnail images extracted from the image file extraction part 51.

[0038] The functionality of a mobile phone is implemented using the built-in antenna 23, the wireless communication part 24, the signal processor 25, the speaker 27, the microphone 28, and the audio processor 29. As the communication scheme for a mobile phone, it is possible to name various schemes such as PDC (Personal Digital Cellular), GSM (Global System for Mobile Communication), CDMA (Code Division Multiple Access), CDMA-2000, and WCDMA (Wideband CDMA). The present invention may adopt any type of schemes.

[0039] The built-in antenna 23 receives radio waves from neighboring base stations or transmits radio waves to neighboring base stations. The wireless communication part 24 performs wireless communication with neighboring base stations. The signal processor 25 processes received/transmitting signals. The speaker 27 produces sound while the microphone 28 receives sound. The audio processor 29 processes various audio signals, such as receiver sound, in order to supply them to the speaker 27. Additionally, it processes audio signals transmitted from the microphone 28.

[0040] According to the first embodiment as described above, when the mobile phone 1 with a camera is operated to shoot a subject image with the image device 21, an image signal from the image device 21 is compressed in the JPEG format, for example, under control of the controller 22 and then stored in the memory 30 as an image file in the Exif format.

[0041] FIG. 2 shows a data configuration of an image file in the Exif format (Exif 2.1). As show in FIG. 2, an image file in the Exif format includes a header, a thumbnail image, and a main image. The header describes camera information at a shooting time, such as a pixel count, a compression mode, a shooting date/time, a device type, an aperture value, and a color space. Main images may have various sizes and various aspect ratios, such as 240320, 480640, 9601280, 10241280, 320240, 640480, 1280960, and 12801024. According to standards, thumbnail images are defined in an aspect ratio 4:3 and in an image size 160120. Additionally, each thumbnail image includes an effective image area which is an area of a main image which is reduced in size while maintaining its aspect ratio.

[0042] The mobile phone 1 with a camera produces square-shaped images with the same size based on thumbnail images included in image files in the Exif format, thus displaying an image list. That is, it displays an image list aligning square-shaped images with the same size, thus improving visibility.

[0043] FIG. 3 is a flowchart showing a process for producing square-shaped images based on thumbnail images included in image files in the Exif format according to the first embodiment of the present invention.

[0044] In FIG. 3, in order to produce square-shaped images based on thumbnail images included in image files in the Exif format, the controller 22 reads image files in the Exif format from the memory 30 so as to extract thumbnail images included in image files in the Exif format (step 101). Next, the controller 22 specifies a short side of an effective image area of each thumbnail image. Subsequently, the controller 22 resizes each thumbnail image while maintaining its aspect ratio so that the size of the specified short side will match with the size of one side of each square-shaped image (step 102). Then, the controller 22 detects the center of a resized image (step 103) so as to extract a square-shaped image with a center of gravity at the center of the resized image (step 104). Thus, it is possible to produce a square-shaped image with a predetermined size, which may include all the pixels on a short side of an effective image area of a thumbnail image. Thus, the controller 22 displays an image list including square-shaped images, each of which is produced as described above (step 105).

[0045] As described above, thumbnail images described in files in the Exif format are each standardized into the aspect ratio 4:3 and the image size 160120. In contrast, main images may have various aspect ratios. Therefore, thumbnail images may cause blanks as shown in FIG. 4.

[0046] In FIG. 4, a thumbnail image 101 exemplifies a thumbnail image with blanks formed at left and right positions. Those blanks occur with respect to a vertically shot image in comparison with a horizontal thumbnail image included in an image file in the Exif format. The short-side length of the thumbnail image 101, accompanied with blanks at left and right positions, is equal to a size A1 in the horizontal direction of an effective image area.

[0047] In FIG. 4, a thumbnail image 201 exemplifies a thumbnail image with blanks at upper and lower positions. Those blanks occur with respect to a horizontally shot image with a wider aspect ratio (e.g. 16:9) than the aspect ratio 4:3 in comparison with a thumbnail image, included in an image file in the Exif format, with an aspect ratio 4:3. The short-side length of the thumbnail image 201, accompanied with blanks at upper and lower positions, is equal to a size B2 in the vertical direction of an effective image area.

[0048] As shown in FIG. 5, an image list may include square-shaped images displayed with a size MM.

[0049] When the thumbnail image 101 shown in FIG. 4 is extracted from an image file in the Exif format which is read from the memory 30 in step 101, the short-side size A1 of an effective image area in the thumbnail image 101 is resized with the one-side size M of a square-shaped image in step 102. Thus, it is possible to generate a resized image 102 as shown in FIG. 4.

[0050] When the thumbnail image 201 shown in FIG. 4 is extracted from an image file in the Exif format which is read from the memory 30 in step 101, the short-side size B2 of an effective image area in the thumbnail image 201 is resized with the one-side size M of a displayed image in step 102. Thus, it is possible to generate a resized image 202.

[0051] As shown in FIG. 4, after generation of the resized images 102, 202, the centers of the resized images 102, 202 are detected in step 103; then, square-shaped images are extracted from the centers of the resized images 102, 202.

[0052] A center P1 is detected from the resized image 102 in step 103; then, a square-shaped portion with the size (MM) is extracted from the center P1 in step 104. Thus, it is possible to generate a square-shaped image 103 with the one-side length M shown in FIG. 4.

[0053] A center P2 is detected from the resized image 202 in step 103; then, a square-sized portion with the size (MM) is extracted from the center P2 in step 104. Thus, it is possible to generate a square-shaped image 203 with the one-side length M as shown in FIG. 4.

[0054] Upon generating square-shaped images, square-shaped images are displayed in an image list as shown in FIG. 6 in step 105. According to the first embodiment of the present invention, the mobile phone 1 with a camera is able to realize alignment of square-shaped images with the same size and without blanks. Thus, it is possible to improve visibility.

[0055] According to the first embodiment of the present invention, as described above, the mobile phone 1 with a camera generates square-shaped images with the same size based on thumbnail images included in image files in the Exif format, thus displaying an image list. Herein, it deals with image data which is thumbnail image data with a small data size, a predetermined image size, and a predetermined aspect ratio. Additionally, it does not need complex calculating processes but it needs a resizing process and an image extracting process. Thus, it is possible to achieve high-speed processing without using a large-capacity memory.

Second Embodiment

[0056] Next, the second embodiment of the present invention will be described. The image display device of the first embodiment is designed to extract a thumbnail image included in an image file in the Exif format, resize the thumbnail image such that a short side of an effective image area will match with one side of a display image, detect the center of the resized image, extract a square-shaped image from the center of the resized image, and produce a square-shaped image having a predetermined size.

[0057] In contrast, the second embodiment is designed to extract a thumbnail image included in an image file in the Exif format, detect the center of the thumbnail image, extract a square-shaped image from the center of the thumbnail image in conformity with an effective image area, resize the extracted square-shaped image, and produce a square-shaped image having a predetermined size. Other parts are identical to those of the first embodiment; hence, duplicate descriptions thereof are precluded herein.

[0058] FIG. 7 is a flowchart showing a process of producing a square-shaped image based on a thumbnail image included in an image file in the Exif format.

[0059] In FIG. 7, in order to generate a square-shaped image based on a thumbnail image included in an image file in the Exif format, the controller 22 reads an image file in the Exif format from the memory 30 and extracts a thumbnail image included in the image file in the Exif format (step 201). Subsequently, the controller 22 detects the center of the thumbnail image (step 202) and extracts a square-shape image from the center of the thumbnail image in conformity with an effective image area (step 203).

[0060] Specifically, the controller 22 extracts a square-shaped image which may include all the pixels on a short side of an effective image area passing through a center of an effective image area included in the thumbnail image. Additionally, the controller 22 resizes the extracted image such that the size of one side of the extracted square-shaped image will match with the size of one side of a square-shaped image (step 204). Thus, it is possible to generate a square-shaped image having a predetermined size, which may include all the pixels on a short side of an effective image area of a thumbnail image. Then, the controller 22 displays an image list including square-shaped images which are generated as described above (step 205).

[0061] In FIG. 8, a thumbnail image 301 exemplifies a thumbnail image with blanks occurring at left and right positions. In FIG. 8, a thumbnail image 401 exemplifies a thumbnail image with blanks occurring at upper and lower positions. Additionally, an image list may include images, each of which should be displayed in the form of a square-shaped image with the size MM.

[0062] When the thumbnail image 301 of FIG. 8 is extracted from an image file in the Exif format read from the memory 30 in step 201, a center P3 of the thumbnail image 301 is detected in step 202; then, an effective image area having a square shape is extracted from the center P3 of the thumbnail image 301 in step 203. Thus, it is possible to extract a square-shaped image 302 in FIG. 8. At this time, the one-side length of the extracted square-shaped image 302 matches with a short-side size A3 of the effective image area of the thumbnail image 301 in the horizontal direction.

[0063] When the thumbnail image 401 of FIG. 8 is extracted from an image file in the Exif format read from the memory 30 in step 201, a center P4 of the thumbnail image 401 is detected in step 202; then, an effective image area having a square shape is extracted from the center P4 of the thumbnail image 401 in step 203. Thus, it is possible to extract a square-shaped image 302 in FIG. 8. At this time, the one-side length of the extracted square-shaped image 402 matches with a short-side size B4 of the effective area of the thumbnail image 401 in the vertical direction.

[0064] In step 204, the one-side sizes of the extracted square-shaped images 302, 402 are each resized in conformity with the one-side size of a square-shaped image.

[0065] In FIG. 8, A3 denotes the one-side length of the extracted square-shaped image 302. Therefore, the one-side length A3 of the extracted square-shaped image 302 is resized in conformity with the one-side length M of a displayed image in step 204. Thus, it is possible to generate a square-shaped image 303 shown in FIG. 8.

[0066] In FIG. 8, B4 denotes the one-side length of the extracted square-shaped image 402. Therefore, the one-side length B4 of the extracted square-shaped image 402 is resized in conformity with the one-side length M of a displayed image. Thus, it is possible to generate a square-shaped image 403.

[0067] The second embodiment of the present invention is designed to display an image list aligning square-shaped images having the same size and precluding blanks, thus improving visibility. Additionally, it deals with image data which is thumbnail image data with a small data size, a predetermined image size, and a predetermined aspect ratio. Additionally, it does not need complex calculating processes but carries out an image extracting process and a resizing process. Thus, it is possible to realize high-speed processing without using a large capacity memory.

[0068] The present invention is not necessarily limited to the foregoing embodiments and therefore adapted to various modifications and applications within the scope not deviating from the subject matter of the present invention.

[0069] The foregoing embodiments are described with respect an image list using square-shaped images having the predetermined size; but this is not a restriction; hence, it is possible to use rectangular images having the predetermined size.

[0070] When the first embodiment employs rectangular images as displayed images, the controller 22 performs the following processing in step 102. That is, the controller 22 performs a resizing process of changing the size of each thumbnail image while maintaining its aspect ratio such that the short-side size of an effective image area will agree with the short-side size of the counterpart image.

[0071] When a rectangular image with the size 160120 is used as a displayed image, for example, the controller 22 determines whether the short side of an effective image area lies in a horizontal direction or in a vertical direction. When the short side of an effective image area lies in the horizontal direction, the controller 22 resizes a thumbnail image to change its size while maintaining its aspect ratio such that the short-side size of an effective image area will agree with the one-side size of a displayed image, i.e. 160, in the horizontal direction. On the other hand, when the short side of an effective image area lies in the vertical direction, the controller 22 resizes a thumbnail image to change its size while maintaining its aspect ratio such that the short-side size of an effective image area will agree with the one-side size of a displayed image, i.e. 120, in the vertical direction.

[0072] Due to the above processing, the first embodiment is redesigned to employ rectangular images as displayed images.

[0073] When the second embodiment employs rectangular images as displayed images, the controller 22 performs the following processing in step 203. That is, the controller 22 performs a process for extracting a rectangular image, with the same aspect ratio as a displayed image, which may include all the pixels on a short side of an effective image area of a thumbnail image.

[0074] When a rectangular image with the size 160120 (aspect ratio 4:3) is used as a displayed image while a thumbnail image includes an effective image area with the size 16090, for example, the controller 22 extracts a rectangular image with the size 12090 (aspect ratio 4:3).

[0075] On the other hand, when a rectangular image with the size 160120 (aspect ratio 4:3) is used as a displayed image while a thumbnail image includes an effective image area with the size 100120, the controller 22 extracts a rectangular image with the size 10075 (aspect ratio 4:3).

[0076] Due to the above processing, the second embodiment is redesigned to use rectangular images as displayed images.

[0077] The present application claims priority based on Japanese Patent Application No. 2010-224652 filed Oct. 4, 2010, the entire content of which is incorporated herein by reference.

INDUSTRIAL APPLICABILITY

[0078] The present invention is applicable to an image display device displaying a list of image files, thus improving visibility in displaying an image list.

REFERENCE SIGNS LIST

[0079] 1: mobile phone [0080] 21: image device [0081] 22: controller [0082] 23: built-in antenna [0083] 24: wireless communication part [0084] 25: signal processor [0085] 27: speaker [0086] 28: microphone [0087] 29: audio processor [0088] 30: memory [0089] 31: display [0090] 32: keys [0091] 51: image file extraction part [0092] 52: square-shaped image generation part