Medical Simulation Lab Weblog http://blog.case.edu/orgs/msssc/ en-us Fri, 19 Aug 2005 15:13:59 EST Fri, 19 Aug 2005 15:13:59 EST marvin.schwartz@case.edu marvin.schwartz@case.edu http://blogs.law.harvard.edu/tech/rss Movable Type v3.121 Starbak Selected http://blog.case.edu/orgs/msssc/2005/08/19/starbak_selected Apple never quite got 2 analog cameras with audio connected to a 2.7GHz dual processor PowerMac to work. We wanted... http://blog.case.edu/orgs/msssc/2005/08/19/starbak_selected AV Architecture Fri, 19 Aug 2005 15:13:59 EST Apple never quite got 2 analog cameras with audio connected to a 2.7GHz dual processor PowerMac to work. We wanted a 2Mbps 640 x 480 x 30 fps H.264 video and AAC audio streamed in real time and recorded. We got a very nice result from 1 analog camera and audio input connected to a Canopus analog to DV converter connected by FireWire to a 2.0GHz dual processor PowerMac running QuickTime Broadcaster 7.0. That required increasing the number of PowerMacs from 17 to 33 and to do that we needed to increase HVAC and power to the PowerMac room. Even before considering the scheduling and control software as defined in the Recording and Distribution System Control document, this was too costly and the Apple approach was rejected.

We will be installing a Starbak video encoding and recording system. Version 1 will not support real time streaming or the recording of video from codecs other than Starbak codecs or 3rd party conferencing codecs. In particular, we will not be able to record the MPEG 4 video video produced by some simulators. Starbak encoders use Windows Media 9 codecs and the interface between the encoders and the recorder is closed. We have included an update to version 2 of the Starbak system which is expected to address these issues.

This completes the decisions for the AV system which will be built and installed as soon as the contracts are in place and the equipment is delivered. With the cabling and power already installed, this phase of the project should move quickly.

The next phase of the system is to get the Recording and Distribution System control software, and the testing and assessment software in place.

In version 1, Starbak provides a 3-level directory hierarchy, category, channel and program. We cannot change the structure but we can name the levels anything we want. Metadata is an editable text block. We will experiment with using a Google or other desktop search tool.

On 8/20/2005, the OSCE exam will use SNAP 8 questionnaires to determine if this is an appropriate testing and assessment tool. If this works, then we are left with the task of determining how we want to use or extend the Starbak scheduling and recording and distribution system control.

MSS 8/19/2005

]]> Cameras http://blog.case.edu/orgs/msssc/2005/06/13/cameras We are still awaiting a demo setup for the network video cameras. The Sony camera has been eliminated due to... http://blog.case.edu/orgs/msssc/2005/06/13/cameras AV Architecture Mon, 13 Jun 2005 12:30:33 EST We are still awaiting a demo setup for the network video cameras. The Sony camera has been eliminated due to its 15 fps limitation when capturing audio. That leaves only the Axis 211A camera. Another vendor reported that there was a 5 second delay before the MPEG4 stream from the Axis camera was available to view on the web. If so, why? For buffering alone, the camera has to keep up in real time.

Having a single source for cameras is a concern. Axis appears to be the only manufacturer of network video cameras that support both audio and 30 fps at 640 by 480. Several cameras provide the desired video but no audio. Since we are preprocessing the audio to remove background noise and increase the clarity of the voices, is there an audio encoder that would let us add the audio to an MPEG4 video stream produced by any network video camera?

]]> Audio Visual System Architecture http://blog.case.edu/orgs/msssc/2005/05/04/audio_visual_system_architecture The audio-visual system is a mission-critical component of the center. It needs to record student-standardized patient encounters in exam rooms,... http://blog.case.edu/orgs/msssc/2005/05/04/audio_visual_system_architecture AV Architecture Wed, 04 May 2005 19:56:11 EST The audio-visual system is a mission-critical component of the center. It needs to record student-standardized patient encounters in exam rooms, team performance in the operating room, emergency room, and ICU, debriefings, and meetings. Audio fidelity is even more important than visual fidelity. It should be possible to hear every word the student and the standardized patient say. It needs to clearly record the audio for team communication, debriefings, and meetings.

Are pan-tilt-zoom cameras necessary everywhere or will fixed cameras do the job? If we use PTZ cameras, who will control them? What is the budget for operators and where do the funds come from? Should the cameras remained fixed to should they follow the student (using an RFID tag or by some other means?

How do we start and stop the recordings and attach a meaningful session identifier to the recorded video?

How do we record the video as well as make it available in real time?

What is the most cost-effective architecture that will meet the needs of the center? What architecture provides the best platform for future expansion?

We will look into network video cameras that stream MPEG4 and support audio. Possible cameras include the Axis 211A (http://www.axis.com/products/cam_211a/index.htm) and the Sony SNC-RZ30N.

MSS 5 May 05

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