Image sensing apparatus and its control method

• US 7,505,074 B2
• Filed: 04/26/2004
• Issued: 03/17/2009
• Est. Priority Date: 02/06/2004
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Yoshino, Hiroaki, Sato, Yoshinobu
• Primary Examiner(s): Ho; Tuan V
• Assistant Examiner(s): WHIPKEY, JASON T
• Application Number:
  US10/831,326
• Publication Number:
  US 20050174457A1
• Time in Patent Office: 1,786 Days
• Field of Search: 348/333.01, 348/333.11, 348/333.05, 348/333.12, 345/660, 345/667, 345/668, 345/669, 345/670, 345/671
• US Class Current: 348/333.11
• CPC Class Codes: H04N 23/634 Warning indications
• CPC Class Codes: H04N 23/635 Region indicators; Field of view indicators
• CPC Class Codes: H04N 23/651 for reducing power consumption by affecting camera operations, e.g. sleep mode, hibernation mode or power off of selective parts of the camera

Abstract

In an initial stage where an image obtained by image sensing is displayed, image data in a resolution depending on an image display area of display unit is displayed, thereby a high response can be maintained with respect to a request to display a next image or the like. Further, if a request with an enlargement ratio higher than that in the initial stage has been made, a display image is generated based on image data in a high resolution, thereby a user'"'"'s request for enlarged display or the like can be fulfilled. When an image (JPEG file) stored in a recording medium is to be displayed, low resolution image data in 640×480 pixel size equivalent to the resolution of the display unit and high resolution image data in an original high resolution indicated with the image file are generated. In the initial stage, the low resolution image data is displayed. If an enlargement request has been made, partial image data cut out from the high resolution image data is resized and is displayed.

Claims

1. A display control apparatus for displaying an image, said apparatus comprising:

a reading unit configured to read encoded image data from a storage medium;

a generating unit configured to decode the encoded image data read by the reading unit and to generate first image data and second image data from the decoded image data, where the first image data has a number of pixels corresponding to a resolution of a display area of a display and the second image data has a number of pixels larger than that of the first image data;

a storage unit configured to temporarily store the first image data and the second image data generated by said generating unit;

a designation unit configured to designate a rotation of the image displayed in the display area;

a determination unit configured to determine whether or not a current enlargement ratio for displaying an image is larger than the enlargement ratio in an initial stage;

a rotation control unit configured to execute rotation processing of the first image data stored in the storage unit if the designation unit designates the rotation and the current enlargement ratio is not larger than that of the initial stage, and to execute rotation processing of the second image data stored in the storage unit if the designation unit designates the rotation and the current enlargement ratio is larger than that of initial stage;

a display control unit configured to control the display to display an image based on the first image data temporarily stored in the storage unit on the display area if the current enlargement ratio is not larger than the enlargement ratio in the initial stage, and to control the display to display a partial image, which is obtained by cutting out from the second image data temporarily stored in the storage unit, on the display area if the current enlargement ratio is larger than the enlargement ratio in the initial stage.

2. The apparatus according to claim 1, further comprising a selection determination unit configured to determine whether or not a selection request to change an image to be displayed has been made,

wherein, when said selection determination unit determines that the selection request to change an image to be displayed has been made, said generating unit decodes another encoded image data and generates first image data and second image data from the decoded image data.

3. The apparatus according to claim 1, further comprising:

a detection unit configured to, referring to additional information added into encoded image data of an image to be displayed, detect an attitude of an image sensing device when an image sensing device has sensed the image to be displayed,

wherein said designation unit automatically designates a rotation of the image in accordance with the attitude detected by said detection unit.

4. The apparatus according to claim 1, wherein, when an instruction of enlargement is inputted while an image based on the first image data is displayed on the display area, said rotation control unit executes the rotation processing of the second image data in accordance with the instruction, and said display control unit controls the display to display a partial image, which is obtained by cutting out from the rotated second image data in accordance with the enlargement ratio determined by said determination unit, on the display area.

5. The apparatus according to claim 1, further comprising:

a scroll determination unit configured to determine whether or not a scroll instruction has been made, and

wherein said display control unit invalidates the scroll instruction determined by said scroll determination unit when the current enlargement ratio is the same as the enlargement ratio in the initial stage, while when the current enlargement ratio is larger than that in the initial stage, controls the display to display a partial image according to the current enlargement ratio, where the partial image is obtained by cutting out from the second image data in accordance with the scroll instruction determined by said scroll determination unit.

6. A display control method for displaying an image, said method comprising:

a reading step of reading encoded image data from a storage medium;

a generating step of decoding the encoded image data read by said reading step and generating first image data and second image data from the decoded image data, where the first image data has a number of pixels corresponding to a resolution of a display area of a display and the second image data has a number of pixels larger than that of the first image data;

a storage step of temporarily storing the first image data and the second image data generated by said generating step;

a designation step of designating a rotation of the image displayed in the display area;

a determination step of determining whether or not a current enlargement ratio for displaying an image is larger than the enlargement ratio in an initial stage;

a rotation control step of executing rotation processing of the first image data stored in the storage step if the designation step designates the rotation and the current enlargement ratio is not larger than that of the initial stage, and executing rotation processing of the second image data stored in the storage step if the designation step designates the rotation and the current enlargement ratio is larger than that of initial stage; and

a display control step of controlling the display to display an image based on the first image data temporarily stored in the storage step on the display area if the current enlargement ratio is not larger the enlargement ratio in the initial stage, and controlling the display to display a partial image, which is obtained by cutting out from the second image data temporarily stored in the storage step, on the display area, if the current enlargement ratio is larger than the enlargement ratio in the initial stage.

7. The method according to claim 6, further comprising a selection determination step of determining whether or not a selection request to change an image to be displayed has been made,

wherein, when said selection determination step determines that the selection request to change an image to be displayed has been made, said generating step decodes another encoded image data and generates first image data and second image data from the decoded image data.

8. The method according to claim 6, further comprising

a detection step, referring to additional information added into encoded image data of an image to be displayed, of detecting an attitude of an image sensing device when the image sensing device has sensed the image to be displayed,

wherein said designation step automatically designates a rotation of the image in accordance with the attitude detected by said detection step.

9. The method according to claim 6, wherein, when an instruction of enlargement is inputted while an image based on the first image data is displayed on the display area, said rotation control step executes the rotation processing of the second image data in accordance with the instruction, and said display control step controls the display to display a partial image, which is obtained by cutting out from the rotated second image data in accordance with the enlargement ratio determined by said determination step, on the display area.

10. The method according to claim 6, further comprising

a scroll determination step of determining whether or not a scroll instruction has been made,

wherein said display control step invalidates the scroll instruction determined by said scroll determination step when the current enlargement ratio is the same as the enlargement ratio in the initial stage, while, when the current enlargement ratio is larger than that of the initial stage, controls the display to display a partial image according to the current enlargement ratio, where the partial image is obtained by cutting out from the second image data in accordance with the scroll instruction determined by said scroll determination step.

11. A computer-readable storage medium encoded with a computer program for instructing a computer to perform a display control method for displaying an image, said display control method comprising:

a reading step of reading encoded image data from a storage medium;

a generating step of decoding the encoded image data read by said reading step and generating first image data and second image data from the decoded image data, where the first image data has a number of pixels corresponding to a resolution of a display area of a display and the second image data has a number of pixels larger than that of the first image data;

a storage step of temporarily storing the first image data and the second image data generated by said generating step;

a designation step of designating a rotation of the image displayed in the display area;

a determination step of determining whether or not a current enlargement ratio for displaying an image is larger than the enlargement ratio in an initial stage;

a rotation control step of executing rotation processing of the first image data stored in the storage step if the designation step designates the rotation and the current enlargement ratio is not larger than that of the initial stage, and executing rotation processing of the second image data stored in the storage step if the designation step designates the rotation and the current enlargement ratio is larger than that of initial stage; and

a display control step of controlling the display to display an image based on the first image data temporarily stored in the storage step on the display area if the current enlargement ratio is not larger than the enlargement ratio in the initial stage, and controlling the display to display a partial image, which is obtained by cutting out from the second image data temporarily stored in the storage step, on the display area, if the current enlargement ratio is larger than the enlargement ratio in the initial stage.