Image processing apparatus, activation control method and non-transitory computer-readable recording medium encoded with activation control program

An activation control method performed by a hardware processor that controls an image processing apparatus,

• the image processing apparatus comprising:
• a volatile first memory;
• a non-volatile second memory;
• a power supply that supplies power to the first memory, the second memory and the hardware processor;
• and
• a delay unit that, in response to generation of a stop trigger for stopping supply of the power by the power supply, delays shut-off of the power supplied to the first memory, the second memory and the hardware processor, and
• the activation control method causing the hardware processor to perform;
• a process execution step of loading a program stored in the second memory into the first memory and executing a process defined by the program;
• a complete deletion step of, after execution of the program ends, deleting data stored in the second memory by execution of the program in the process execution step by overwriting the data with predetermined data for complete deletion of the stored data;
• a snapshot preparation step of, in response to generation of a stop trigger for causing the power supply to stop supplying the power, storing data, stored in the first memory, in the second memory as a snapshot;
• and
• an activation step of, in response to generation of a start trigger for causing the power supply to start supplying power, transferring the snapshot stored in the second memory to the first memory, wherein
• the snapshot preparation step includes a step of, in the case where prospective deletion data to be deleted in the complete deletion step is stored in the second memory in a stage where the stop trigger is generated, stopping deletion of the prospective deletion data and overwriting the prospective deletion data with the snapshot,
• (i) the activation control method causing the hardware processor to further perform;
• a comparison step of comparing a size of the snapshot with a size of the prospective deletion data,
• a compression step of compressing the snapshot;
• and
• a switching step of, in the case where the size of the snapshot is larger than the size of the prospective deletion data, switching a storage mode to a compression mode in which the snapshot is compressed for storage, and in the case where the size of the snapshot is equal to or smaller than the size of the prospective deletion data, switching the storage mode to a non-compression mode in which the snapshot is stored without being compressed, or
• (ii) the activation control method causing the hardware processor to further perform a remaining portion deletion step of, in the case where a size of the snapshot is smaller than a size of the prospective deletion data, deleting a portion, which has not be overwritten with the snapshot, of the prospective deletion data by overwriting the portion with the predetermined data, or
• (iii) the activation control method causing the hardware processor to further perform a pre-stop deletion step of, in the case where prospective deletion data to be deleted in the complete deletion step is stored in the second memory after storage of the snapshot is completed in the snapshot preparation step, deleting the prospective deletion data stored in the second memory by overwriting the prospective deletion data with the predetermined data, or
• (iv) the activation control method causing the hardware processor to further perform:
• a prospective deletion data identification information storage step of, after the stop trigger for causing the power supply to stop supplying the power is generated, storing prospective deletion data identification information, for identifying prospective deletion data to be deleted in the complete deletion step, in the second memory, and
• a post-activation deletion step of, in the case where the prospective deletion data identification information is stored in the second memory after the generation of the start trigger, overwriting the prospective deletion data identified by the prospective deletion, data identification information with the predetermined data.

A non-transitory computer-readable recording medium encoded with an activation control program executed by a hardware processor that controls an image processing apparatus,

• the image processing apparatus comprising:
• a volatile first memory;
• a non-volatile second memory;
• and
• a delay unit that, in response to generation of a stop trigger for stopping supply of power by a power supply, delays shut-off of the power supplied to the first memory, the second memory and the hardware processor, and
• the activation control program causing the hardware processor to perform:
• a process execution step of loading a program stored in the second memory into the first memory and executing a process defined by the program;
• a complete deletion step of, after execution of the program ends, deleting data stored in the second memory by execution of the program in the process execution step by overwriting the stored data with predetermined data for complete deletion of the stored data;
• a snapshot preparation step of, in response to generation of a stop trigger for causing the power supply to stop supplying the power, storing data, stored in the first memory, in the second memory as a snapshot;
• and
• an activation step of, in response to generation of a start trigger for causing the power supply to start supplying the power, transferring the snapshot stored in the second memory to the first memory, wherein
• the snapshot preparation step includes a step of, in the case where prospective deletion data to be deleted in the complete deletion step is stored in the second memory in a stage where the stop trigger is generated, stopping deletion of the prospective deletion data and overwriting the prospective deletion data with the snapshot,
• (i) the activation control method causing the hardware processor to further perform;
• a comparison step of comparing a size of the snapshot with a size of the prospective deletion data,
• a compression step of compressing the snapshot;
• and
• a switching step of, in the case where the size of the snapshot is larger than the size of the prospective deletion data, switching a storage mode to a compression mode in which the snapshot is compressed for storage, and in the case where the size of the snapshot is equal to or smaller than the size of the prospective deletion data, switching the storage mode to a non-compression mode in which the snapshot is stored without being compressed, or
• (ii) the activation control method causing the hardware processor to further perform a remaining portion deletion step of, in the case where a size of the snapshot is smaller than a size of the prospective deletion data, deleting a portion, which has not be overwritten with the snapshot, of the prospective deletion data by overwriting the portion with the predetermined data, or
• (iii) the activation control method causing the hardware processor to further perform a pre-stop deletion step of, in the case where prospective deletion data to be deleted in the complete deletion step is stored in the second memory after storage of the snapshot is completed in the snapshot preparation step, deleting the prospective deletion data stored in the second memory by overwriting the prospective deletion data with the predetermined data, or
• (iv) the activation control method causing the hardware processor to further perform;
• a prospective deletion data identification information storage step of, after the stop trigger for causing the power supply to stop supplying the power is generated, storing prospective deletion data identification information, for identifying prospective deletion data to be deleted in the complete deletion step, in the second memory, and
• a post-activation deletion step of, in the case where the prospective deletion data identification information is stored in the second memory after the generation of the start trigger, overwriting the prospective deletion data identified by the prospective deletion data identification information with the predetermined data.

An image processing apparatus, comprising:

• a hardware processor that controls the image processing apparatus;
• a volatile first memory that stores operation environment information of the hardware processor;
• and
• a non-volatile second memory that stores image data to be processed by the image processing apparatus, wherein
• when an instruction to turn off a power supply of the image processing apparatus is given, the hardware processor overwrites the image data stored in the second memory with the operation environment information stored in the first memory to delete the image data before a supply of power to the hardware processor, the first memory, and the second memory ends, wherein
• when the hardware processor overwrites the image data stored in the second memory with the operation environment information stored in the first memory to delete the image data, in the case where a data size of the operation environment information is smaller than a size of the image data, the hardware processor overwrites a portion, which has not been overwritten with the operation environment information, of the image data with predetermined data to delete the portion.