Image decompressing apparatus, control method thereof, and non-transitory computer-readable storage medium

An image decompressing apparatus for decompressing encoded image data, the apparatus comprising:

• a first decompressing unit configured to decompress encoded data of a preset type on a block basis;
• a second decompressing unit configured to decompress encoded data of a block in which encoded data of a plurality of types coexist;
• an identifying unit configured to identify a type of encoded data for each block of input encoded image data;
• a generating unit configured to,
• in a case in which a type of encoded data of a block of interest identified by the identifying unit is a single type that can be decompressed by the first decompressing unit, store the encoded data of the block of interest in a predetermined memory, and
• in a case in which encoded data of a plurality of types that cannot be decompressed by the first decompressing unit are included, store encoded data of a single type in the encoded data of the block of interest, which can be decompressed by the first decompressing unit, in the predetermined memory as the encoded data of the block of interest, thereby generating encoded image data that can be decompressed by the first decompressing unit;
• and
• a control unit configured to control the first decompressing unit to decompress the encoded data generated by the generating unit and generate tentative image data, then controls the second decompressing unit to decompress the encoded data of a remaining type that cannot be decompressed by the first decompressing unit, and update the tentative image data to the decompression result, thereby generating image data to be output.

A control method of an image decompressing apparatus for decompressing encoded image data, the method comprising:

• a first decompressing step of decompressing encoded data of a preset type;
• a second decompressing step of performing decompression processing of encoded data of a type that the decompressing does not support;
• an identifying step of identifying a type of encoded data for each block of input encoded image data;
• a generating step of,
• in a case in which a type of encoded data of a block of interest identified in the identifying step is a type that can be decompressed in the first decompressing step, storing the encoded data of the block of interest in a predetermined memory, and
• in a case in which the type is a type that cannot be decompressed in the first decompressing step, storing predetermined encoded data that can be decompressed in the first decompressing step in the predetermined memory, thereby generating encoded image data that can be decompressed in the first decompressing step;
• and
• a controlling step of controlling the decompressing to decompress the encoded data generated in the first generating step to generate tentative image data, and then controlling the second decompression step to decompress the encoded data that cannot be decompressed in the first decompressing step, and update the tentative image data to the decompression result, thereby generating image data to be output.

A control method of an image decompressing apparatus for decompressing encoded image data, the method comprising:

• a first decompressing step of decompressing encoded data of a preset type on a block basis;
• a second decompressing step of decompressing encoded data of a block in which encoded data of a plurality of types coexist;
• an identifying step of identifying a type of encoded data for each block of input encoded image data;
• a generating step of,
• in a case in which a type of encoded data of a block of interest identified in the identifying step is a single type that can be decompressed in the first decompressing step, storing the encoded data of the block of interest in a predetermined memory, and
• in a case in which encoded data of a plurality of types that cannot be decompressed in the first decompressing step are included, storing encoded data of a single type in the encoded data of the block of interest, which can be decompressed in the first decompressing step, in the predetermined memory as the encoded data of the block of interest, thereby generating encoded image data that can be decompressed in the first decompressing;
• and
• controlling the first decompressing step to decompress the encoded data generated in the generating step to generate tentative image data, then controlling the second decompressing step to decompress the encoded data of a remaining type that cannot be decompressed in the first decompressing step, and updating the tentative image data to the decompression result, thereby generating image data to be output.

A non-transitory computer-readable storage medium storing a program which, when read and executed by a computer, causes the computer to execute the steps of a control method of an image decompressing apparatus for decompressing encoded image data, the method comprising:

• a first decompressing step of decompressing encoded data of a preset type;
• a second decompressing step of performing decompression processing of encoded data of a type that the decompressing does not support;
• an identifying step of identifying a type of encoded data for each block of input encoded image data;
• a generating step of,
• in a case in which a type of encoded data of a block of interest identified in the identifying step is a type that can be decompressed in the first decompressing step, storing the encoded data of the block of interest in a predetermined memory, and
• in a case in which the type is a type that cannot be decompressed in the first decompressing step, storing predetermined encoded data that can be decompressed in the first decompressing step in the predetermined memory, thereby generating encoded image data that can be decompressed in the first decompressing step;
• and
• a controlling step of controlling the decompressing to decompress the encoded data generated in the first generating step to generate tentative image data, and then controlling the second decompression step to decompress the encoded data that cannot be decompressed in the first decompressing step, and update the tentative image data to the decompression result, thereby generating image data to be output.

A non-transitory computer-readable storage medium storing a program which, when read and executed by a computer, causes the computer to execute the steps of a control method of an image decompressing apparatus for decompressing encoded image data, the method comprising:

• a first decompressing step of decompressing encoded data of a preset type on a block basis;
• a second decompressing step of decompressing encoded data of a block in which encoded data of a plurality of types coexist;
• an identifying step of identifying a type of encoded data for each block of input encoded image data;
• a generating step of,
• in a case in which a type of encoded data of a block of interest identified in the identifying step is a single type that can be decompressed in the first decompressing step, storing the encoded data of the block of interest in a predetermined memory, and
• in a case in which encoded data of a plurality of types that cannot be decompressed in the first decompressing step are included, storing encoded data of a single type in the encoded data of the block of interest, which can be decompressed in the first decompressing step, in the predetermined memory as the encoded data of the block of interest, thereby generating encoded image data that can be decompressed in the first decompressing;
• and
• controlling the first decompressing step to decompress the encoded data generated in the generating step to generate tentative image data, then controlling the second decompressing step to decompress the encoded data of a remaining type that cannot be decompressed in the first decompressing step, and updating the tentative image data to the decompression result, thereby generating image data to be output.