An image processing apparatus, in which preprocessed image data is inputted in every frame, and subjected to predetermined processing for outputting, and the processed image data is outputted in every frame, the apparatus comprising: reference data generating means for generating first reference data one time in one term made up of not less than two consecutive frames, and also outputting specific reference data in every frame; data compressing means for performing compression processing on the first reference data one time in the one term, to generate compressed reference data; a memory for storing the compressed reference data; data expanding means for performing expansion processing on the compressed reference data stored in the memory, to generate restored reference data in every frame; and output image data generating means for generating the processed image data based on the specific reference data and the preprocessed image data, wherein the reference data generating means is configured to execute processing for each frame in the term as follows: in a first frame in the term, the reference data generating means outputs as the specific reference data the restored reference data generated by the data expanding means based on the compressed reference data stored in the memory, to the output image data generating means, in an intermediate frame other than the first frame and a final frame in the term, the reference data generating means outputs the specific reference data generated on the basis of the restored reference data generated by the data expanding means based on the compressed reference data stored in the memory and the preprocessed image data of the intermediate frame, to the output image data generating means, and in the final frame in the term, the reference data generating means generates the specific reference data on the basis of the restored reference data generated by the data expanding means based on the compressed reference data stored in the memory and the preprocessed image data of the final frame, to the output image data generating means, and also generates the first reference data based on the specific reference data and the preprocessed image data of the final frame, to output the generated first reference data to the data compressing means. reference data generating means for generating first reference data one time in one term made up of not less than two consecutive frames, and also outputting specific reference data in every frame; data compressing means for performing compression processing on the first reference data one time in the one term, to generate compressed reference data; a memory for storing the compressed reference data; data expanding means for performing expansion processing on the compressed reference data stored in the memory, to generate restored reference data in every frame; and output image data generating means for generating the processed image data based on the specific reference data and the preprocessed image data, wherein the reference data generating means is configured to execute processing for each frame in the term as follows: in a first frame in the term, the reference data generating means outputs as the specific reference data the restored reference data generated by the data expanding means based on the compressed reference data stored in the memory, to the output image data generating means, in an intermediate frame other than the first frame and a final frame in the term, the reference data generating means outputs the specific reference data generated on the basis of the restored reference data generated by the data expanding means based on the compressed reference data stored in the memory and the preprocessed image data of the intermediate frame, to the output image data generating means, and in the final frame in the term, the reference data generating means generates the specific reference data on the basis of the restored reference data generated by the data expanding means based on the compressed reference data stored in the memory and the preprocessed image data of the final frame, to the output image data generating means, and also generates the first reference data based on the specific reference data and the preprocessed image data of the final frame, to output the generated first reference data to the data compressing means. in a first frame in the term, the reference data generating means outputs as the specific reference data the restored reference data generated by the data expanding means based on the compressed reference data stored in the memory, to the output image data generating means, in an intermediate frame other than the first frame and a final frame in the term, the reference data generating means outputs the specific reference data generated on the basis of the restored reference data generated by the data expanding means based on the compressed reference data stored in the memory and the preprocessed image data of the intermediate frame, to the output image data generating means, and in the final frame in the term, the reference data generating means generates the specific reference data on the basis of the restored reference data generated by the data expanding means based on the compressed reference data stored in the memory and the preprocessed image data of the final frame, to the output image data generating means, and also generates the first reference data based on the specific reference data and the preprocessed image data of the final frame, to output the generated first reference data to the data compressing means.