Motion video signal processing for recording or reproducing – Local trick play processing – With randomly accessible medium
Reexamination Certificate
1999-05-04
2004-11-30
Boccio, Vincent (Department: 2615)
Motion video signal processing for recording or reproducing
Local trick play processing
With randomly accessible medium
C386S349000, C386S349000
Reexamination Certificate
active
06826350
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a high-speed signal search method, device, and recording medium (which records this method) that searches a signal sequence for the location of a signal that is similar to a pre-recorded signal. This recording medium records a program for executing by computer this high-speed signal search method, and is computer readable. The present invention can be used, for example, for audio signal detection. That is, the present invention relates to signal detection technology which can detect and automatically record the time a specified commercial was broadcast in a broadcast audio signal, and start and stop video recording by detecting a specified theme song.
In addition, the present invention is related to technology that can automatically monitor the timing of applause, the timing of laughter, etc. in a broadcast, and search for a specified scene. Furthermore, the present invention can be applied to the detection of signals in general (video signals, etc.), not just audio signals.
This application is based patent applications filed in Japan (Japanese Patent Application, No. Hei 10-151723, Japanese Patent Application, No. Hei 10-244162, and Japanese Patent Application, No. Hei 11-49184), the contents of which are incorporated herein by reference.
2. Prior Art
A matched filter is a conventional technique of detecting in a signal sequence a region having a desired signal (referred to hereinbelow as a “reference signal”). A matched filter is a technique wherein a correlation between the waveform of the area of the object input signal (referred to hereinbelow as a “window”) and the waveform of a reference signal is calculated as the window moves, and when the correlation value exceeds a fixed value, it is determined that the reference signal is within the window.
However, in this method, there is the problem that because it is necessary to calculate the correlation value while precisely moving the position of the window with respect to the entire area of the input signal, the amount of calculation becomes enormous, and the calculation speed becomes slow.
In contrast, instead of using the correlation value between the input signal waveform and a reference signal waveform, there is also the technique of calculating the feature quantities (that is, a numerical value or a set of numerical values indicating the feature of the signal waveform) of the input signal waveform in this window, and carrying out a comparison between this input signal waveform and the reference signal waveform by using, for example, the correlation value or Euclidean distance between this feature quantity and the feature quantity of a reference signal waveform calculated in advance.
However, in this method as well, there is the problem that it is necessary to calculate the feature quantities while precisely moving the position of the window with respect to the entire area of the input signal, and because it is necessary to compare feature quantities, the amount of calculation becomes enormous, and the speed of calculation is slow.
SUMMARY OF THE INVENTION
In consideration of the above-described problems, it is an object of the present invention to provide a high-speed signal search method, device, and recording medium for the same which can obtain a detection result equivalent to the case of precisely moving with respect to the entire area even if the window is not precisely moved with respect to the entire area of the input signal.
In addition, another object of the present invention is to provide a high-speed signal search method, device, and recording medium for the same which can detect a signal with higher precision even when it is difficult to discriminate the signal with average features or when the signal fluctuates due to noise, etc.
Furthermore, another object of the present invention is to provide a high-speed signal search method, device, and recording medium for the same which can detect a signal with less processing than conventionally even when the signal is detected based on a plurality of reference signals.
This invention provides a first step that generates a feature quantity sequence for a pre-recorded reference signal, a second step that sets the input signal window for the input signal that has been input, a third step that generates a feature quantity sequence for the input signal of this input signal window, a fourth step that calculates the input signal similarity value showing the degree of similarity between the feature quantity sequence generated in the first step and the feature quantity sequence generated in the third step, a fifth step that calculates the skip width showing the amount that the input signal window can be moved based on the input signal similarity value calculated in the fourth step, and a sixth step that determines the position of the input signal window based on the skip width calculated in the fifth step, sets the input signal window to this position, and further calculates the input signal similarity value for each position of the input signal window by repeating the third step to the sixth step, and determines whether or not the reference signal exists at the position that the input signal window presently shows in the input signal based on the result of comparing the input signal similarity value and the predetermined threshold value.
According to another feature, the present invention provides a first step that generates a feature quantity sequence for a pre-recorded reference signal, a second step that produces a histogram of the feature quantity generated in the first step, a third step that sets the input signal window for the input signal that has been input, a fourth step that generates a feature quantity sequence for the input signal of this input signal window, a fifth step that produces a histogram of the feature quantity sequence generated in the fourth step, a sixth step that calculates the input signal similarity value showing the degree of similarity between the histogram produced in the second step and the histogram produced in the fifth step, a seventh step that calculates a skip width indicating the amount that the input signal window can be moved based on the input signal similarity value calculated in the sixth step, and an eight step that determines the position of the input signal window based on the skip width calculated in the seventh step, and sets the input signal window at that position, and further, calculates the input signal similarity value for each position of the input signal window by repeating the fourth step to the eighth step, and determines whether or not the reference signal exists at the position that the input signal window presently shows in the input signal based on the result of comparing the input signal similarity value and the predetermined threshold value.
According to another feature, the present invention provides a first step that generates a feature quantity sequence for a pre-recorded reference signal, a second step that sets the reference signal window for the feature quantity sequence generated in the first step, a third step that partitions the reference signal window set in the second step into a plurality of partitioned reference signal windows, a fourth step that generates a feature quantity sequence for the input signal that has been input, a fifth step that sets the input signal window for the feature quantity sequence generated in the fourth step, a sixth step that partitions this input signal window into a plurality of partitioned input signal windows corresponding to the plurality of partitioned reference signal windows, a seventh step that calculates the input signal similarity value showing the degree of similarity between the feature quantity sequence of each reference signal partition window and the feature quantity sequence in the partitioned input signal windows corresponding to the relevant partitioned reference signal window, an eighth step that calculates a skip width indicating the amount that the input signal window c
Kashino Kunio
Murase Hiroshi
Smith Gavin
Boccio Vincent
Nippon Telegraph and Telephone Corporation
Thelen Reid & Priest LLP
LandOfFree
High-speed signal search method device and recording medium... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with High-speed signal search method device and recording medium..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and High-speed signal search method device and recording medium... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3361091