Then, the minimum circumscribed circle and shape principal orientation of the object region are calculated; and the object region is divided into some blocks in the polar coordinate, which uses the center of the minimum circumscribed circle as the origin and the direction of the shape principal orientation as the direction of the polar axis, and the features of all subblocks are extracted to compose shape histograms and then smoothed; then, combined with global features to synthetically represent the content of the image; finally, a new image similarity is used to compute the distance between images 首先对商标图像进行预处理,得到规则二值图像;计算目标像素的最小外接圆和图像的形状主方向;在以最小外接圆圆心为原点、形状主方向为极轴方向的极坐标中将图像分块,提取各子块特征,构成形状直方图并平滑处理;再结合全局形状特征来综合表示图像内容;最后采用新的相似性度量方法计算图像间距离,实现商标图像的准确检索。
Then, the minimum circumscribed circle and shape principal orientation of the object region are calculated; and the object region is divided into some blocks in the polar coordinate, which uses the center of the minimum circumscribed circle as the origin and the direction of the shape principal orientation as the direction of the polar axis, and the features of all subblocks are extracted to compose shape histograms and then smoothed; then, combined with global features to synthetically represent the content of the image; finally, a new image similarity is used to compute the distance between images 首先对商标图像进行预处理,得到规则二值图像;计算目标像素的最小外接圆和图像的形状主方向;在以最小外接圆圆心为原点、形状主方向为极轴方向的极坐标中将图像分块,提取各子块特征,构成形状直方图并平滑处理;再结合全局形状特征来综合表示图像内容;最后采用新的相似性度量方法计算图像间距离,实现商标图像的准确检索。