Research data gathering
Methods, apparatus and articles of manufacture for research data gathering are disclosed. Example apparatus disclosed herein to recover a code from media include memory including computer readable instructions, and a processor to execute the instructions to at least process the media based on a sample corresponding to a first window of time to determine whether the code is recoverable from the media using the first window of time, and in response to determining that the code is not recoverable from the media using the first window of time, process the media again based on a sample corresponding to a second window of time larger than the first window of time to recover the code from the media.
1. An apparatus to recover a code from media, the apparatus comprising:
memory including computer readable instructions; and
a processor to execute the instructions to at least:
perform up to a first number of first processing passes through the media based on a first window of time to determine whether the code is recoverable from the media using the first window of time, respective ones of the first processing passes to process samples of the media corresponding to the same first window of time, the samples for a first one of the first processing passes to be offset relative to the samples for a second one of the first processing passes; and
in response to a determination that the code is not recoverable from the media using the first window of time, perform up to a second number of second processing passes through the media based on a second window of time larger than the first window of time to recover the code from the media, respective ones of the second processing passes to process samples of the media corresponding to the same second window of time, the samples for a first one of the second processing passes to be offset relative to the samples for a second one of the second processing passes.
2. The apparatus of claim 1 , wherein to perform a first one of the first processing passes through the media, the processor is to accumulate a first component of the media over the first window of time, and to perform a first one of the second processing passes through the media, the processor is to accumulate the first component of the media over the second window of time.
3. The apparatus of claim 2 , wherein the first component of the media includes a first frequency component of the media.
4. The apparatus of claim 3 , wherein the first frequency component of the media corresponds to a first bin of a Fourier transform, and the processor is to:
determine respective Fourier transforms of successive portions of the media;
accumulate the first frequency component of the media over the first window of time by accumulating the first bins of a first group of the Fourier transforms corresponding to the first window of time; and
accumulate the first frequency component of the media over the second window of time by accumulating the first bins of a second group of the Fourier transforms corresponding to the second window of time.
5. The apparatus of claim 1 , wherein to perform a first one of the first processing passes through the media, the processor is to process a first group of successive samples of the media having respective lengths corresponding to the first window of time, and to perform a first one of the second processing passes through the media, the processor is to process a second group of successive samples of the media having respective lengths corresponding to the second window of time.
6. The apparatus of claim 5 , wherein the first group of successive samples of the media includes overlapping segments of the media, and the second group of successive samples of the media includes overlapping segments of the media.
7. The apparatus of claim 1 , wherein the processor is further to perform up to a third number of second processing passes through the media based on a third window of time larger than the second window of time to recover the code from the media in response to a determination that the code is not recoverable from the media using the second window of time.
8. The apparatus of claim 1 , wherein the code includes symbols forming a repeating message.
9. The apparatus of claim 1 , wherein the second number of second processing passes is greater than the first number of first processing passes.
10. An article of manufacture comprising computer readable instructions that, when executed, cause a processor to at least:
perform up to a first number of first processing passes through media based on a first window of time to determine whether a code is recoverable from the media using the first window of time, respective ones of the first processing passes to process samples of the media corresponding to the same first window of time, the samples for a first one of the first processing passes to be offset relative to the samples for a second one of the first processing passes; and
in response to a determination that the code is not recoverable from the media using the first window of time, perform up to a second number of second processing passes through the media based on a second window of time larger than the first window of time to recover the code from the media, respective ones of the second processing passes to process samples of the media corresponding to the same second window of time, the samples for a first one of the second processing passes to be offset relative to the samples for a second one of the second processing passes.
11. The article of manufacture of claim 10 , wherein to perform a first one of the first processing passes through the media, the instructions, when executed, cause the processor to accumulate a first component of the media over the first window of time, and to perform a first one of the second processing passes through the media, the instructions, when executed, cause the processor to accumulate the first component of the media over the second window of time.
12. The article of manufacture of claim 11 , wherein the first component of the media includes a first frequency component of the media.
13. The article of manufacture of claim 12 , wherein the first frequency component of the media corresponds to a first bin of a Fourier transform, and the instructions, when executed, cause the processor to:
determine respective Fourier transforms of successive portions of the media;
accumulate the first frequency component of the media over the first window of time by accumulating the first bins of a first group of the Fourier transforms corresponding to the first window of time; and
accumulate the first frequency component of the media over the second window of time by accumulating the first bins of a second group of the Fourier transforms corresponding to the second window of time.
14. The article of manufacture of claim 10 , wherein to perform a first one of the first processing passes through the media, the instructions, when executed, cause the processor to process a first group of successive samples of the media having respective lengths corresponding to the first window of time, and to perform a first one of the second processing passes through the media, the instructions, when executed, cause the processor to process a second group of successive samples of the media having respective lengths corresponding to the second window of time.
15. The article of manufacture of claim 14 , wherein the first group of successive samples of the media includes overlapping segments of the media, and the second group of successive samples of the media includes overlapping segments of the media.
16. The article of manufacture of claim 10 , wherein the instructions, when executed, further cause the processor to perform up to a third number of second processing passes through the media based on a third window of time larger than the second window of time to recover the code from the media in response to a determination that the code is not recoverable from the media using the second window of time.
17. The article of manufacture of claim 10 , wherein the code includes symbols forming a repeating message.
18. The article of manufacture of claim 10 , wherein the second number of second processing passes is greater than the first number of first processing passes.
19. A method to recover a code from media, the method comprising:
performing, by executing an instruction with a processor, up to a first number of first processing passes through the media based on a first window of time to determine whether the code is recoverable from the media using the first window of time, respective ones of the first processing passes to process samples of the media corresponding to the same first window of time, the samples for a first one of the first processing passes to be offset relative to the samples for a second one of the first processing passes; and
in response to determining that the code is not recoverable from the media using the first window of time, performing, by executing an instruction with the processor, up to a second number of second processing passes through the media based on a second window of time larger than the first window of time to recover the code from the media, respective ones of the second processing passes to process samples of the media corresponding to the same second window of time, the samples for a first one of the second processing passes to be offset relative to the samples for a second one of the second processing passes.
20. The method of claim 19 , wherein the performing of a first one of the first processing passes through the media based on the first window of time includes accumulating a first component of the media over the first window of time, and the performing of a first one of the second processing passes through the media based on the second window of time includes accumulating the first component of the media over the second window of time.
21. The method of claim 19 , wherein the performing of a first one of the first processing passes through the media based on the first window of time includes processing a first group of successive samples of the media having respective lengths corresponding to the first window of time, and the performing of a first one of the second processing passes through the media based on the second window of time includes processing a second group of successive samples of the media having respective lengths corresponding to the second window of time.
22. The method of claim 19 , further including, in response to determining that the code is not recoverable from the media using the second window of time, performing up to a third number of second processing passes through the media again on a third window of time larger than the second window of time to recover the code from the media.
23. The method of claim 19 , wherein the second number of second processing passes is greater than the first number of first processing passes.