Random Research Notes
This is a directory for random pages describing little incidental
research results that perhaps deserve to be documented, but don't fit in
- Notes on some ICASSP-2000 papers
- Both as a reminder to myself and for any use they may be to others in the group, I've tried to make brief notes on the papers I noticed at the just-passed ICASSP-2000.
- Label-conditional spectral feature averages
- Following Hynek Hermansky's presentation of Sangita Sharma's research on using very long time windows, I calculated the average time-frequency planes for the different labels over a 70 hour data set. We also see a wide influence of several hundred milliseconds.
- Temporal structure of Modulation Spectrogram features
- The plots of the Modulation-filtered Spectrogram MSG1 features (that
we've been using in Broadcast News) are quite surprising.
- Comparison of different feature types
- I did a series of tests of basic features with and without
rasta processing. For the NUMBERS95 task I used, all variants
gave more or less the same result, which was odd.
- Frame-rate adaptive RASTA transfer function
- The RASTA filter is partially defined in terms of its modulation-frequency response, so I modified the code to take a stab at maintaining the same response even when the steptime is not the canonical 10ms. This plot compares the
responses for 10ms and 16ms frame rates.
- Examples of phone-less words from STP
- This is Eric's collection of Switchboard examples with audible words
that appear to lack any acoustic correlates.
- Correlation of different feature types
- Florian Schiel asked Morgan for a reference to the 'received wisdom'
that the cepstral transform 'decorrelates' spectral coefficients.
I did some measurements comparing the two to see how much difference
there really was.
DAn Ellis <firstname.lastname@example.org>
International Computer Science Institute, Berkeley CA