An image processing device comprising: a decoding section (62, 63, 64) configured to decode an encoded stream to generate an image; a horizontal filtering section configured to apply horizontal deblocking filters across a plurality of vertical boundaries to pixels neighboring the vertical boundaries, without dependency on processing accompanied by vertical deblocking filter between the horizontal deblocking filters from each other for the plurality of vertical boundaries, the vertical boundaries being vertical boundaries between blocks within the image generated by the decoding section; a vertical filtering section configured to apply vertical deblocking filters across a plurality of horizontal boundaries to pixels neighboring the horizontal boundaries, the horizontal boundaries being horizontal boundaries between blocks within a filtered image including the pixels to which the horizontal deblocking filters have been applied by the horizontal filtering section; and a control section configured to: control the horizontal filtering section, such that the horizontal deblocking filters are applied to pixels neighboring all vertical boundaries to which it is determined to apply the horizontal deblocking filters, within a largest coding unit or a slice of the image, and control the vertical filtering section, such that the vertical deblocking filters are applied to pixels neighboring all horizontal boundaries to which it is determined to apply the vertical deblocking filters, within the largest coding unit or the slice of the filtered image including the pixels to which the horizontal deblocking filters have been applied by the horizontal filtering section. a decoding section (62, 63, 64) configured to decode an encoded stream to generate an image; a horizontal filtering section configured to apply horizontal deblocking filters across a plurality of vertical boundaries to pixels neighboring the vertical boundaries, without dependency on processing accompanied by vertical deblocking filter between the horizontal deblocking filters from each other for the plurality of vertical boundaries, the vertical boundaries being vertical boundaries between blocks within the image generated by the decoding section; a vertical filtering section configured to apply vertical deblocking filters across a plurality of horizontal boundaries to pixels neighboring the horizontal boundaries, the horizontal boundaries being horizontal boundaries between blocks within a filtered image including the pixels to which the horizontal deblocking filters have been applied by the horizontal filtering section; and a control section configured to: control the horizontal filtering section, such that the horizontal deblocking filters are applied to pixels neighboring all vertical boundaries to which it is determined to apply the horizontal deblocking filters, within a largest coding unit or a slice of the image, and control the vertical filtering section, such that the vertical deblocking filters are applied to pixels neighboring all horizontal boundaries to which it is determined to apply the vertical deblocking filters, within the largest coding unit or the slice of the filtered image including the pixels to which the horizontal deblocking filters have been applied by the horizontal filtering section. control the horizontal filtering section, such that the horizontal deblocking filters are applied to pixels neighboring all vertical boundaries to which it is determined to apply the horizontal deblocking filters, within a largest coding unit or a slice of the image, and control the vertical filtering section, such that the vertical deblocking filters are applied to pixels neighboring all horizontal boundaries to which it is determined to apply the vertical deblocking filters, within the largest coding unit or the slice of the filtered image including the pixels to which the horizontal deblocking filters have been applied by the horizontal filtering section.