Remove incorrect decimation in FFT spectrum #137
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Addresse #132. When the FFT spectrum is cropped by lowering the max frequency, the signal was decimated N times by taking one sample every N samples. This is not correct, produces many artifacts. To keep decimation, we would need to use a proper low-pass filter (as implemented for the octave spectum for example), but it does not really seem worth it. We will just apply the FFT on top of the undecimated signal.
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Addresses #132. When the FFT spectrum is cropped by lowering the max frequency, the signal was decimated N times by taking one sample every N samples. This is not correct, produces many artifacts. To keep decimation, we would need to use a proper low-pass filter (as implemented for the octave spectum for example), but it does not really seem worth it. We will just apply the FFT on top of the undecimated signal.