2 REQUIREMENTS RELATING TO SIGN LANGUAGE INTERPRETATION
2.1 Quality of display
The presentation of the signer on the intended display screen should be of sufficient size and resolution to show all movements of the full upper trunk together with arms, hands and fingers, shoulder, neck and all relevant facial movements and expressions. All important gestures that convey meaning through sign language must be easily and accurately recognised.
2.2 Size and shape of overlaid inserts
The size of the overlay must ensure that the body and facial expressions referred to above are easily discernible from normal viewing distances. Where practicable a signer's image, when at rest, that is notionally framed to occupy at least one sixth of the picture area would normally be sufficient to ensure this condition is met.
For programmes primarily aimed at deaf people and in the “open” format a useful technique, which deaf people prefer, can be to reduce the visual image by, for example, 25 per cent and use the subsequent blank area to place the interpreter.
2.4. Choice of dress and background colours
It is important that the person signing can be clearly distinguished, for example by means of contrasting plain colours and suitable lighting. The visual appearance of the interpreter (e.g. choice of clothing and dress accessories) should not cause undue distraction to the viewer.
2.5. Speaker identification
This can be achieved by the signer using such techniques as referencing to a person by shifts in the eye gaze and body positioning or giving the speaker’s name and reflecting his or her manner. (This technique is known as characterisation).