1. A high-speed signal search method characterized in providing:
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 can be moved based on the input signal similarity value calculated in the seventh step; and
a ninth step which determines the position of the input signal window based on the skip width calculated in the eighth step and sets the input signal window at that position; and further,
calculates an input signal similarity value for each position of the input signal window by repeating the sixth step to the ninth 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.
2. A high-speed signal search method according to claim 1 characterized in providing:
a pre-check step which finds in advance the similarity value between an input signal and a reference signal for a plurality of locations on said input signal;
pre-check similarity value statistics step which find the mean and the standard deviation of this similarity value for the plurality of similarity values obtained in said pre-check step;
a threshold value determination step which determines said threshold value based on the mean and standard deviation obtained in said pre-check similarity value statistics step.
3. A high-speed signal search method according to claim 1 characterized in said input signal similarity value being the intersection similarity value.
4. A high-speed signal search method according to claim 1 characterized in said input signal window having the same time length as said reference signal in the direction of the time axis.
5. A high-speed signal search method according to claim 1 characterized in said skip width being calculated by
w
=
{
floor
\u2062
\u2062
(
D
\u2061
(
\u03b8
–
S
)
)
+
1
(
S
<
\u03b8
)
1
(
otherwise
)
where:
0 is said threshold value;
S is said input signal similarity value;
D is the total frequency of said feature quantity sequence; and
Floor { } denotes the cutoff for rounding off the number.
6. A high-speed signal search method according to claim 1 characterized in said reference signal and said input signal being an audio signal.
7. A high-speed signal search method characterized in providing:
a first step that generates a feature quantity sequence for a pre-recorded reference signal;
a second step that sets a 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 tot his plurality of partitioned reference signal windows;
a seventh step that produces a histogram of the feature quantity sequence of each partitioned reference signal window;
an eighth step that produces a histogram of a feature quantity sequence of each partitioned input signal window;
a ninth step that calculates the input signal similarity value showing the degree of similarity between the histogram of each partitioned reference signal window and the histogram of the partitioned input signal window corresponding to the relevant partitioned reference signal window;
a tenth step that calculates the skip width showing the amount that the input signal window can move based on the input signal similarity value calculated in the ninth step; and
an eleventh step that determines the position of the input signal window and sets the input signal window at that position; and further,
calculates an input signal similarity value for each position of the input signal window by repeating the sixth step to the eleventh 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.
8. A high-speed signal search method according to claim 7 characterized in:
said feature quantity sequence being a sequence of zero-crossing feature quantities of the reference signal and the input signal, and its integral value; and
said histogram being produced by partitioning the range of value that said zero-crossing number and its integral value can take into a plurality of bins, and calculates the feature quantity sequence corresponding to each of said bins based on said zero-crossing number and its integral value.
9. A high-speed signal search method according to claim 7 characterized in:
said feature quantity sequence is a sequence of feature vectors having a plurality of frequency band components as elements; and
said histogram being produced by partitioning the range of values that each of the elements of said feature vector can take into a plurality of bins, and calculating the feature quantity sequence corresponding to each of said bins based on the value of said elements.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A controller comprising:
current setting circuitry operable for selectively operating in different states, said states including a strobe state and an idle state, setting a current of a light source to a first current level in said strobe state such that said light source emits light, and setting said current to a second current level that is less than said first current level in said idle state such that said light source disables emission of light; and
voltage regulation circuitry, coupled to said current setting circuitry, operable for regulating an output voltage that powers said light source to be in a voltage range with said current at said first current level in said strobe state such that said light source emits light, and maintaining said output voltage at a voltage level in said voltage range in said idle state.
2. The controller of claim 1, wherein said current setting circuitry comprises:
a sensing circuit operable for sensing said current to generate a sense signal; and
a comparing circuit, coupled to said sensing circuit, operable for comparing said sense signal with a preset threshold, and generating a control signal to said voltage regulation circuitry to control said output voltage according to a result of said comparing.
3. The controller of claim 2, wherein said voltage regulation circuitry regulates said output voltage to a target voltage; wherein in said strobe state, said voltage regulation circuitry adjusts said target voltage according to said control signal, and wherein in said idle state, said voltage regulation circuitry maintains said target voltage at a preset level.
4. The controller of claim 3, wherein in said strobe state, said voltage regulation circuitry increases said target voltage if said sense signal is less than said preset threshold, and decreases said target voltage if said sense signal is greater than said preset threshold.
5. The controller of claim 1, wherein said current setting circuitry comprises:
a regulation circuit operable for regulating said current to a reference current level; and
a reference setting circuit, coupled to said regulation circuit, operable for setting said reference current level to said first current level in said strobe state, and setting said reference current level to said second current level in said idle state.
6. The controller of claim 5, wherein said regulation circuit comprises:
a switch operable for allowing said current to pass through said switch;
a resistive component, coupled to said switch, operable for allowing said current to pass through said resistive component; and
an operational amplifier, coupled to said resistive component and said switch, and comprising a first input terminal operable for receiving a reference voltage, a second input terminal operable for applying a level of said reference voltage to said resistive component to set said current, and an output terminal operable for controlling said switch.
7. The controller of claim 1, wherein the minimum voltage of said voltage range is equal to or greater than a threshold voltage that enables said light source to emit light.
8. An electronic device comprising:
a light source operable for emitting light in a strobe state and disabling emission of light in an idle state;
current setting circuitry, coupled to said light source, operable for controlling said light source to operate in said strobe state by setting a current of said light source to a first current level in said strobe state, and controlling said light source to operate in said idle state by setting said current to a second current level that is less than said first current level in said idle state; and
voltage regulation circuitry, coupled to said light source and said current setting circuitry, operable for regulating an output voltage that powers said light source to be in a voltage range with said current at said first current level in said strobe state such that said light source emits light, and maintaining said output voltage at a voltage level in said voltage range in said idle state.
9. The electronic device of claim 8, wherein said current setting circuitry comprises:
a sensing circuit operable for sensing said current to generate a sense signal; and
a comparing circuit, coupled to said sensing circuit, operable for comparing said sense signal with a preset threshold, and generating a control signal to said voltage regulation circuitry to control said output voltage according to a result of said comparing.
10. The electronic device of claim 9, wherein said voltage regulation circuitry regulates said output voltage to a target voltage; wherein in said strobe state, said voltage regulation circuitry adjusts said target voltage according to said control signal, and wherein in said idle state, said voltage regulation circuitry maintains said target voltage at a preset level.
11. The electronic device of claim 10, wherein in said strobe state, said voltage regulation circuitry increases said target voltage if said sense signal is less than said preset threshold, and decreases said target voltage if said sense signal is greater than said preset threshold.
12. The electronic device of claim 8, wherein said current setting circuitry comprises:
a regulation circuit operable for regulating said current to a reference current level; and
a reference setting circuit, coupled to said regulation circuit, operable for setting said reference current level to said first current level in said strobe state, and setting said reference current level to said second current level in said idle state.
13. A method comprising:
controlling a light source to selectively operate in different states, said states including a strobe state and an idle state;
regulating an output voltage that powers said light source to be in a voltage range in said strobe state such that said light source emits light;
setting, using current setting circuitry coupled to said light source, a current of said light source to a first current level in said strobe state such that said light source emits said light;
maintaining said output voltage in said voltage range in said idle state; and
setting said current to a second current level that is less than said first current level in said idle state such that said light source disables emission of light.
14. The method of claim 13, wherein said regulating of said output voltage comprises:
sensing said current to generate a sense signal;
comparing said sense signal with a preset threshold; and
generating a control signal to control said output voltage according to a result of said comparing.
15. The method of claim 14, further comprising:
regulating said output voltage to a target voltage;
adjusting said target voltage according to said control signal in said strobe state; and
maintaining said target voltage at a preset level in said idle state.
16. The method of claim 13, further comprising:
regulating, using a regulation circuit, said current to a reference current level;
setting said reference current level to said first current level in said strobe state; and
setting said reference current level to said second current level in said idle state.
17. A controller comprising:
a first pin operable for providing power to a light source;
a second pin operable for receiving a current of said light source;
control circuitry, coupled to said first and second pins, operable for selectively operating in different states including a strobe state and an idle state, controlling said power to regulate an output voltage at said light source to be in a voltage range in said strobe state such that said light source emits light, regulating said current to a first current level in said strobe state such that said light source emits light, controlling said power to maintain said output voltage at a voltage level in said voltage range in said idle state, and regulating said current to a second current level that is less than said first current level in said idle state such that said light source disables emission of light.
18. The controller of claim 17, wherein said control circuitry comprises:
a sensing circuit operable for sensing said current to generate a sense signal; and
a comparing circuit, coupled to said sensing circuit, operable for comparing said sense signal with a preset threshold, and generating a control to control said output voltage according to a result of said comparing.
19. The controller of claim 18, wherein said control circuitry regulates said output voltage to a target voltage, wherein in said strobe state, said control circuitry adjusts said target voltage according to said control signal, and wherein in said idle state, said control circuitry maintains said target voltage at a preset level.
20. The controller of claim 17, wherein said control circuitry comprises:
a regulation circuit operable for regulating said current to a reference current level; and
a reference setting circuit, coupled to said regulation circuit, operable for setting said reference current level to said first current level in said strobe state, and setting said reference current level to said second current level in said idle state.