An electronic device comprising: a camera module including an image sensor; a display comprising a touch screen; a power management module; and a processor functionally connected to the image sensor and the display, wherein the processor is configured to: in response to detecting a gesture through the touch screen: command the power management module to supply power to the camera module; and in response to a release of the gesture detected through the touch screen: transmit a first drive command to the image sensor, receive first image data from the image sensor as a response to the first drive command, generate image processing data by processing the first image data, encode the image processing data, and store the encoded data; wherein said gesture is an object such as a finger or a pen moving in a state of contacting or hovering over the touch screen, and said release of said gesture means release of contact between said object and said touch screen or release of said hovering object from said touch screen; and said processor is further configured to: in response to detecting through the touch screen a stop of the object moving over the touch screen: transmit a second drive command to the image sensor, receive second image data from the image sensor as a response to the second drive command, generate first display processing data by processing the second image data, and control the display to display the first display processing data by converting the first display processing data to a preview image; and in response to said release of the gesture detected through the touch screen, furthermore: generate second display processing data, said image processing data having a greater capacity than the second display processing data, and control the display to display the second display processing data by converting the second display processing data to an image. a camera module including an image sensor; a display comprising a touch screen; a power management module; and a processor functionally connected to the image sensor and the display, in response to detecting a gesture through the touch screen: command the power management module to supply power to the camera module; and in response to a release of the gesture detected through the touch screen: transmit a first drive command to the image sensor, receive first image data from the image sensor as a response to the first drive command, generate image processing data by processing the first image data, encode the image processing data, and store the encoded data; wherein said gesture is an object such as a finger or a pen moving in a state of contacting or hovering over the touch screen, and said release of said gesture means release of contact between said object and said touch screen or release of said hovering object from said touch screen; and said processor is further configured to: in response to detecting through the touch screen a stop of the object moving over the touch screen: transmit a second drive command to the image sensor, receive second image data from the image sensor as a response to the second drive command, generate first display processing data by processing the second image data, and control the display to display the first display processing data by converting the first display processing data to a preview image; and in response to said release of the gesture detected through the touch screen, furthermore: generate second display processing data, said image processing data having a greater capacity than the second display processing data, and control the display to display the second display processing data by converting the second display processing data to an image. in response to detecting through the touch screen a stop of the object moving over the touch screen: transmit a second drive command to the image sensor, receive second image data from the image sensor as a response to the second drive command, generate first display processing data by processing the second image data, and control the display to display the first display processing data by converting the first display processing data to a preview image; and in response to said release of the gesture detected through the touch screen, furthermore: generate second display processing data, said image processing data having a greater capacity than the second display processing data, and control the display to display the second display processing data by converting the second display processing data to an image.