The invention provides a video high-level characteristic retrieval
system based on a plurality of bottom-level characteristics of color, edge, texture,
characteristic point and the like and a supportvector
machine (SVM). Shot
boundary detection is firstly carried out on a video clip, and then a plurality of representative frames are extracted at equal intervals from a shot to be as key frames. For the extracted key frames, a plurality of robust bottom-level characteristics of color, edge, texture and
characteristic point are extracted. The adoption of the bottom-level characteristics provides description in different respects for video high-level semantic characteristics, because the low-level characteristics has strong complementarity and can respectively present strong differentiatingcapability for different semantic concepts, so that the detection performances of the
system for different concepts can be ensured. The extracted characteristics are respectively sent to the
support vector machine (SVM) for classification to form a multi-
branch subsystem. In the concept classification stage, the
support vector machine (SVM) is selected as a classifier, a method based on condensednearest neighbor is firstly used for selecting training parameters, so that the ubiquitous problem in training process of imbalance of positive and negative samples is effectively solved. In order tofully utilize the description information provided by a plurality of subsystems, a two-grade integrating strategy is adopted for the classification scores of the multi-
branch subsystem, and a method of
logistic regression is introduced to learn the optimal integrating strategy, so that the accuracy and the recall ratio of an integrating
system are greatly improved.