Issues concerning the collection and pre-processing of audio, video, and auxiliary data, and resolution status
As
indicated in the table below, some of the recordings are affected by
signal discontinuities. In most cases, this was due to a sudden failure
by the audio recording equipment. For the purpose of generating
transcriptions and annotated data for these files, the signals were
concatenated with zero padding (performed on 48kHz files) in
correspondence with the length of the discontinuity. Frame dropping
also occurred with some of the video signals collected in Edinburgh and
IDIAP when encoding them from DV tape to DivX. These have undergone
additional processing and are now synchronized with the audio signals.
Due to hardware issues during the recording stage, video signals
collected at TNO are not perfectly synchronized. However, data for
these have undergone an additional processing step (see Meeting
Rooms), and now exhibit
acceptable levels of synchronization.
Other data collection issues relate to seat swapping by meeting participants. In a few cases, this has resulted in the mislabeling of participant IDs and thumbnails. A very small number of meetings also feature an inappropriate positioning of headset microphones. In one meeting, a participant removes his headset altogether. These and other data collection and pre-processing issues are presented in the following table, along with details of whether and, where relevant, how the issue was resolved.
| MEETING ID | PROBLEM | RESOLVED (Y/N) | NOTES |
| * all meetings | Logitech I/O digital pen output not synchronized with rest of data | N | pens' internal clocks do not drift by more than a few seconds during each meeting, providing sufficiently accurate calibration |
| E and I meetings | some frame drops in video signals when encoding from DV tape to DivX | Y | video now synchronized with audio signals |
| IN1014 | Recording stops before the end of the meeting. | N/A | |
| IS1000a | PM and UI remove microphones for part of meeting | N/A | |
| IS1000b | PM and UI swap seats | N/A | |
| IS1000c | audio dropout | N | videos un-synched with audio after 23:05; no audio dropout timing information available |
| IS1001c,d | ID and UI swap seats before meeting | N/A | |
| IS1002* | incomplete trial due to dropout in IS1002a | N | |
| IS1003b | no mic array audio |
N |
lost |
| IS1003c,d | ID and UI swap seats before meetings | N/A | correct map in metadata xml files |
| IS1005* | incomplete trial due to dropout in IS1005d | N | |
| IS1007d | no mic array audio | N | lost |