- ActiveX
- A loosely defined set of technologies developed by Microsoft. ActiveX is an outgrowth of two other Microsoft technologies called OLE (Object Linking and Embedding) and COM (Component Object Model). As a moniker, ActiveX can be very confusing because it applies to a whole set of COM-based technologies. Most people, however, think only of ActiveX controls, which represent a specific way of implementing ActiveX technologies. Many lesson observation systems will deploy ActiveX - although from the users' perspective it will be preinstalled and generally invisible.
- Applet
- An applet is a small program written in Java. The EarthCam Applet is a program that looks at a specific image URL and checks if the image has updated. If so, it loads and displays it seamlessly. Applets are generally prevalent in classroom observation systems that have some sort of remotely hosted feature and thus some form of graphical user interface.
- Analogue based
- Many of the older style lesson observation systems that entailed an observatory behind a one way mirror would use analogue digital video recorders and analogue CCTV cameras. Cutting edge at the time, these systems were very expensive, lacked audio fidelity and picture quality, as well as the fact that they were unscalable - only footage from this one room could be captured, and the systems were rarely portable. It was also not possible to implement all the latest software tagging and dibba functionality with such analogue based lesson observation systems.
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- Bandwidth
- The measure of how quickly you can move information from one point to another. All top end lesson observation systems will come with compression technology that will compress the AV data into a manageable size for the school network. A good kbps bench mark for high resolution across a school network would be 750kbps. All bonafide teacher observation companies will have a good handle on their kbps and will be able to demonstrate their exact kbps on a demo system through your school network.
- Client
- A software program that is used to contact and obtain data from a server software program on another computer, often across a great distance. Each client program is designed to work with one or more specific kind of server program and each server requires a specific kind of client. As a school you will generally use client applications when setting up viewing PCs around the school thus enabling teachers to view live and/or pre recorded lessons from multiple PCs.
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- Dibba
- All research points to the fact that the most effective way for teachers to improve is to be able to review footage of themselves teaching, with this reviewing becoming even more powerful if conducted with a mentor. Rapidly becoming a staple of all top end classroom observation solutions, the dibba is the handheld device that gives teachers the all important control over the process of filming their own lessons so that they can be reviewed at a later date. By enabling teachers to turn the system on and off as well as automatically archiving the lesson the dibba puts the teacher firmly in control of their self-filmed lesson observations. As well as being a crucial element within the lesson observation mix it has also become a requirement from the ICO in that the ICO's investigation into correct lesson observation practice means that all legal systems must enable the teacher to be able to turn the system on and off at will.
- Dibba Reader
- For self-filming lesson observation to be truly teacher-centric the system must enable teachers to decide if, when and where they want to film their lessons. A dibba reader enables teachers to turn the recording system on and off at will via swiping their dibba against it.
- Digitize
- Converting NTSC or other analogue video formats into a digital format that can be stored and viewed on a computer. This is becoming less of a buzz word in lesson observation circles due to the fact that most effective classroom observation systems now record digitally in the first instance.
- DualView
- When a teacher films their own lesson there is no third party observer. It is thus crucial that the teacher can deploy two cameras focussed on them self and the pupils respectively. This means that upon review the teacher can watch themselves teach as well as seeing the pupils' reactions to their teaching.
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- Fidelity
- Similar to lip-synching, the actual quality of the audio is fundamentally important. Teacher and pupil dialogue must be clearly audible and the microphone system should ideally be mixed and filtered so as to minimise the squeaking of chairs and tapping of pencils.
- Fixed Room Lesson Observation System
- As the name suggests, the system is permanently fitted into a classroom. Dibba functionality is achieved via a wall mounted dibba reader and cameras and sound equipment are fitted into the walls and ceiling.
The benefit of the fixed lesson observation solution is that there is zero setup time, with the filming of the lesson being started by a single swipe from the teacher's dibba. The downside to a fixed room is that teachers and pupils have to be channelled through the room, this channelling can sometimes lead to a false teaching and learning environment due to the teaching and learning taking place in an unfamiliar room. It is for this reason that schools will typically opt to have a fixed room in each subject head room.
- GIF (Graphic Interchange Format)
- Classroom observation video systems can output still images of a video. GIF is a common format for such image files, especially suitable for images containing large areas of the same colour. GIF format files of simple images are often smaller than the same file would be if stored in JPEG format, but GIF format does not store photographic images as well as JPEG.
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- Host
- Any computer on a school network that is a repository for services available to other computers on the network. It is common to have one host machine provide several services, such as WWW, TELNET, and FTP. IP lesson observation systems will frequently have a host server that will be located in the school server room.
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- IP based
- Classroom observation solutions are increasingly becoming IP based and thus using the network of the school to handle and store the video and audio that has been filmed. IP based systems suit teacher observation systems due to their scalability and the crucial factor of being able to put the teacher in control of the system via the IP based dibba card.
- ISP (Internet Service Provider)
- An institution that provides access to the Internet in some form, usually for money. Lesson observation solution providers, if they offer a remotely hosted solution, will generally be ISP facing for the school, with the lesson observation platform effectively being a managed service.
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- JPEG (Joint Photographic Experts Group)
- JPEG is most commonly mentioned as a format for image files. JPEG format is preferred to the GIF format for photographic images as opposed to line art or simple logo art. Webcams typically produce JPEG images.
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- Lapel Microphone
- Mobile classroom observation units generally have powerful omnidirectional microphones inbuilt that will record general classroom dialogue. However, teachers will often require the ability to record just their own voice in very high quality, this is most important when teachers are creating master classes for pupil revision. When making a mobile unit purchasing decision always check that the system has an inbuilt lapel microphone system.
- Lesson Capture
- This is simply another term for lesson observation or classroom observation. Usage of this phrase is usually an indicator that the particular lesson observation system has its roots in either the Far East or America.
- Lip Synch
- When teachers are reviewing their own lessons, or a lesson is being observed live in real-time, lip synched audio is imperative. Even a slight lag makes the video footage unusable as a CPD tool. Lip synched audio is one the key differentiators between entry level and top end lesson observation solutions. Always ask the company to prove it can lip synch its audio and video in its proprietary and exported formats before committing to a purchase.
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- Megapixel Camera
- Megapixel Cameras are IP (or Network) based cameras built around megapixel technology. These cameras produce large, hi-resolution images. This type of system is more suited for archival applications than for live, real-time viewing. In classroom observation usage they often result in a loss of real-time video when streamed over the school network. Megapixel cameras can also drastically impact upon the school network unless powerful compression technology is not coupled onto the camera.
- MJPEG
- MJPEG stands for "Motion JPEG" and is a JPEG-based codec. MJPEG is identical to JPEG except that the MJPEG codecs have translators built-in to support the different capture cards. MJPEG is not the same as MPEG, although the names are confusingly similar. The primary difference is that MPEG provides temporal compression, while MJPEG only provides spatial compression. MJPEG codecs are often used as storage formats for large files that need to be archived with good quality. It is a lossy codec, but at 100% quality, the image degradation is minimal. All the JPEG codecs require significant amounts of CPU power and are not well suited for video playback. Large image and/or high frame rate movies usually don't play smoothly.
- Mobile Lesson Observation Units
- Scalability and flexibility are must have's for any lesson observation system. Having portable units that enable teachers to film lessons from any classroom in the school opens up the system to all teachers, who no longer have to channel their pupils into the one room in the school that has a fixed system, as has historically been the case with the old style observation rooms.
Top end mobile units should always have high quality fidelity and video, be able to work seamlessly through the school's wireless network, as well as having dibba functionality and onboard camera controls
- MPEG (Moving Picture Experts Group)
- Pronounced m-peg, a working group of ISO. The term also refers to the family of digital video compression standards and file formats developed by the group. MPEG generally produces better-quality video than competing formats, such as Video for Windows, Indeo and QuickTime. MPEG files can be decoded by special hardware or by software.
- MPEG-4
- MPEG-4 is a graphics and video compression algorithm standard that is based on MPEG-1, MPEG-2 and Apple QuickTime technology. Wavelet-based MPEG-4 files are smaller than JPEG or QuickTime files, so they are designed to transmit video and images over a narrower bandwidth and can mix video with text, graphics and 2-D and 3-D animation layers. MPEG-4 was standardized in October 1998 in the ISO/IEC document 14496.
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- NTSC (National Television Standards Committee)
- A video standard established by the United States (RCA/NBC) and adopted by numerous other countries. This is a 525-line video with 3.58-MHz chroma subcarrier and 60 cycles per second. Frames are displayed at 30 fps.
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- Omnidirectional boundary microphone
- These microphones enable ultimate audio pick-up from multiple audio sources. They like to be mounted on a flat hard surface as their mounting surface acts a channel into the mic itself. Whenever looking at a mobile lesson observation, or a fixed lesson observation solution always check to see if the microphone is of sufficiently high spec and is mounted correctly. Sound is as important as the pictures when a teacher is reviewing their own lesson footage, hence it is imperative that high quality audio equipment is specified.
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- Onboard Camera Controls
- When teachers are filming their own lessons they need to be able to setup the camera very quickly before the lesson commences. This is made possible by having an LCD viewing screen on the mobile unit as well as manual controls to enable the teacher to focus the camera in on the area of the lesson they are looking to film.
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- PAL (Phase Alternative Line System)
- The European TV standard based upon 50 cycles per second electrical system and 625 lines per frame and 25 fps. (NTSC, the North American standard is based on 30 frames per second; French use SECAM).
- Plug-In
- A software program that enhances a larger program. Common examples are plug-ins for web browsers that would allow a Webcam to be viewed over a network. A specific browser plug-in is usually required to view streaming media like Windows Media. The idea behind plug-ins is that a small piece of software is loaded into memory by the larger program adding a new feature allowing users to only install the few plug-ins that they need out of a much larger pool of possibilities.
- Portable Lesson Observation System
- Please see Mobile Lesson Observation Units
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- Remote functionality
- This refers to the ability for a lesson observation system to enable remote observation within the school. The old observation suites with one way mirrors obviously piped the video and audio a few feet into the observatory room. With IP based systems coupled with a mobile camera system there are no distance restrictions and an observer can watch a lesson being taught at the other end of the school, or from the other side of the country via a VPN.
- Router
- A hardware device that routes data from a local area network (LAN) to another network connection. A router is connected to at least two networks, commonly two LANs or WANs or a LAN and its ISP's network. The routing of traffic is crucial for effective IP based lesson observation systems, especially when quality of service is required.
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- SDSL (Symmetric Digital Subscriber Line)
- DSL line with identical upstream and downstream speeds. Typically better suited for webcam applications than ADSL.
- Self Observation
- A crucial element of any AV lesson observation solution is for teachers to be able to film their own lessons without any third party involvement, and to improve their teaching skills via self-review. The system must thus be able to be rapidly deployed by the teacher prior to the lesson commencing, as well as being easy to use. Teachers are busy enough as it is without requiring them to spend extra time setting up the system during their brief time window prior to the lesson.
- Server
- A computer or a software package that provides a specific kind of service to client software running on other computers. All IP based lesson observation solutions will have a server of one description or another. School's server rooms are becoming increasingly full and thus space is at a premium. A lesson observation server will typically be 4U and 19 inches in dimension, although virtualisation of servers is now becoming a trend in the market - where schools can use their existing framework to effectively clone the lesson observation server onto their infrastructure.
- Streaming Audio/Video
- Technology that allows you to play audio and/or video while it is still downloading. Streaming technology will be prevalent in a teacher observation system that is hosted remotely, as pre-recorded lessons will have to be streamed over the internet when they are played back.
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- Tagging
- When a teacher reviews their own lesson or a lesson is being observed live it is imperative that the video can be tagged. Tagging can be done in accordance with the professional standards, Ofsted and with self created tags. Audio tagging is also being offered. Tagging lesson footage provides many advantages:
- Once tagged the user can then fast-forward to the points of interest
- Once tagged those individual clips can be exported into Mpeg4 format - enabling a quick and intuitive way to accrue specific examples of teaching
- Tagging lesson observation footage creates teaching highlights, meaning that hours and hours of general lesson footage does not build up and in turn become an unusable mountain of old footage.
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- UDP
- Particularly useful for transmission via a school network, the User Datagram Protocol (UDP) is one of the core members of the Internet Protocol Suite, the set of network protocols used for the Internet. With UDP, computer applications can send messages, in this case referred to as datagrams, to other hosts on an Internet Protocol (IP) network without requiring prior communications to set up special transmission channels or data paths.
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- VPN
- Standing for virtual private network. A VPN is a powerful networking tool to enable schools to be able to remotely view each other's lessons live or pre-recorded. Careful attention must be paid to making sure there is not too much latency which can compromise real-time video and lip-synched audio. Specific Local Authority network regulations must also be looked at carefully before any VPN project is embarked on.
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- Wireless
- With many schools now having site wide wireless networks it is imperative that mobile lesson observation systems can make use of them. Top end mobile lesson observation solutions will enable you to ask the supplier to preconfigure the mobile units for your specific wireless network. Although, your wireless network will need to be of a reasonable speed and have total school coverage to avoid it effecting the video and audio of the lesson observation.
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