An image processing method that causes an image corresponding to input image data to be displayed on an image display device by using a panel self-refresh function including panel self-refresh (PSR) and panel self-refresh 2 (PSR2) by means of an image processing device, the image processing method comprising:
- a step of controlling the panel self-refresh function, by means of a panel self-refresh control circuit of the image processing device;
- a step of performing, on selected image data, image processing applied to an image corresponding to the selected image data, by means of a first image processing circuit of the image processing device;
- a step of generating a switch signal controlling switching of image data, by means of a switch signal generating circuit of the image processing device;
- a step of, in response to the switch signal, switching between the input image data and image data read out from a frame buffer through control by the panel self-refresh control circuit so as to output one of the input image data and the image data read out, by means of a first switch circuit of the image processing device;
- a step of, in response to the switch signal, switching between the input image data and the image data having undergone the image processing so as to output one of the input image data and the image data having undergone the image processing, by means of a second switch circuit of the image processing device;
- a step of, in response to the switch signal, switching between the input image data and the image data having undergone the image processing so as to output one of the input image data and the image data having undergone the image processing, by means of a third switch circuit of the image processing device;
- and
- a step of, in response to the switch signal, switching between image data output from the third switch circuit and the image data read out from the frame buffer so as to output one of the image data output from the third switch circuit and the image data read out, by means of a fourth switch circuit of the image processing device,
- wherein the step of generating the switch signal includes:
- a step of generating, as the switch signal, a first switch signal that controls switching of image data in the first switch circuit such that the input image data is output in a normal operation mode where an image corresponding to the input image data is displayed by normal operation, a panel self-refresh start mode where the input image data is written in the frame buffer before the panel self-refresh starts, a panel self-refresh end mode where phase adjustment between the input image data and the image data read out from the frame buffer is carried out before the panel self-refresh ends, and a panel self-refresh 2 start mode where the input image data is written in the frame buffer before the panel self-refresh 2 starts, and the image data read out from the frame buffer is output in a panel self-refresh 2 mode where a still image is displayed by the panel self-refresh 2, and a panel self-refresh 2 end mode where phase adjustment between the input image data and the image data read out from the frame buffer is carried out before the panel self-refresh 2 ends, when the image processing is performed,
- a step of generating, as the switch signal, a second switch signal that controls switching of image data in the second switch circuit such that the input image data is output in the panel self-refresh start mode, the panel self-refresh end mode, the panel self-refresh 2 start mode and the panel self-refresh 2 end mode when the image processing is not performed, and that the input image data is output in the panel self-refresh 2 start mode and the panel self-refresh 2 end mode, and the image data having undergone the image processing is output in the panel self-refresh start mode and the panel self-refresh end mode, when the image processing is performed,
- a step of generating, as the switch signal, a third switch signal that controls switching of image data in the third switch circuit such that the input image data is output in the normal operation mode, the panel self-refresh start mode, the panel self-refresh end mode, the panel self-refresh 2 start mode and the panel self-refresh 2 end mode when the image processing is not performed, and that the image data having undergone the image processing is output in the normal operation mode, the panel self-refresh start mode, the panel self-refresh end mode, the panel self-refresh 2 start mode, the panel self-refresh 2 mode and the panel self-refresh 2 end mode when the image processing is performed, and
- a step of generating, as the switch signal, a fourth switch signal that controls switching of image data in the fourth switch circuit such that image data output from the third switch circuit is output in the normal operation mode, the panel self-refresh start mode and the panel self-refresh 2 start mode when the image processing is not performed and in the normal operation mode, the panel self-refresh start mode, the panel self-refresh 2 start mode, the panel self-refresh 2 mode and the panel self-refresh 2 end mode when the image processing is performed, and that the image data read out from the frame buffer is output in a panel self-refresh mode where a still image is displayed by the panel self-refresh, the panel self-refresh end mode, the panel self-refresh 2 mode and the panel self-refresh 2 end mode when the image processing is not performed and in the panel self-refresh mode and the panel self-refresh end mode when the image processing is performed.