Photo image retrieval system and program

A photo image retrieval system that stores a plurality of photo images and a plurality of text data, and extracts and displays any of the photo images using an input retrieval sentence as an index, the system comprising:

• a processor;
• a photo image database that records data of the photo images together with information about image capture dates;
• a text database that stores thereon the text data;
• a text data analysis unit that parses the text data in the text database, and extracts words of the text data;
• a page table that records, through provision of a page identification (ID) to each of the text data, dates when the text data is recorded into the text database and storage locations thereof;
• a word table that provides a word ID to each of the words extracted by the text data analysis unit for recording together with a word name;
• a word/page table that records the word ID of each of the words extracted by the text data analysis unit using the page ID as an index;
• a retrieval sentence analysis unit that parses the input retrieval sentence, and extracts words in the retrieval sentence;
• a retrieval word acquisition unit that acquires a retrieval word from the words extracted by the retrieval sentence analysis unit;
• a date range information acquisition unit that acquires information about a date range from the words extracted by the retrieval sentence analysis unit;
• a date range page specification unit that specifies, using as an index the information about the date range, page IDs fitting in the date range by referring to the page table;
• a word ID acquisition unit that extracts, using as an index the retrieval word, any of the word IDs of the word equivalent to the retrieval word by referring to the word table;
• a page ID acquisition unit that acquires, using as an index the word ID extracted by the word ID acquisition unit, the page IDs including the word by referring to the word/page table;
• a date specification unit that extracts, using as an index the page ID acquired by the page ID acquisition unit, any of the page IDs fitting in the date range specified by the date range page specification unit by referring to the page table, and specifies the date of the text data under the extracted page ID;
• a photo image extraction unit that extracts, using as an index the date specified by the date specification unit, any of the photo images captured on the date by referring to the photo image database;
• and
• a display unit that displays the photo image extracted by the photo image extraction unit.