From e822265512a05ffa9b74acd1c99d119f5c3b586f Mon Sep 17 00:00:00 2001 From: Robin Daermann Date: Sat, 29 Aug 2015 10:06:56 +0200 Subject: [PATCH] Add Documentation for Privacy zones --- docs/userguide/definezone.rst | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/docs/userguide/definezone.rst b/docs/userguide/definezone.rst index 1a221b196..d3eaeb8c6 100644 --- a/docs/userguide/definezone.rst +++ b/docs/userguide/definezone.rst @@ -17,7 +17,7 @@ Name Each Zone can be named for reference purposes. It is used for logging and debugging. Choose a name that helps you identify your zones. Type - This is one of the more important concepts in ZoneMinder and there are five to choose from. + This is one of the more important concepts in ZoneMinder and there are six to choose from. * Active Triggers an alarm when motion is detected within it. This is the zone type you'll use most often, and which will be set for your default zone. Only Active and Exclusive zones can trigger an alarm. @@ -32,7 +32,10 @@ Type This zone type is relatively recent. It is called a Preclusive zone because if it is triggered it actually precludes an alarm being generated for that image frame. So motion or other changes that occur in a Preclusive zone will have the effect of ensuring that no alarm occurs at all. The application for this zone type is primarily as a shortcut for detecting general large-scale lighting or other changes. Generally this may be achieved by limiting the maximum number of alarm pixels or other measure in an Active zone. However in some cases that zone may cover an area where the area of variable illumination occurs in different places as the sun and/or shadows move and it thus may be difficult to come up with general values. Additionally, if the sun comes out rapidly then although the initial change may be ignored in this way as the reference image catches up an alarm may ultimately be triggered as the image becomes less different. Using one or more Preclusive zones offers a different approach. Preclusive zones are designed to be fairly small, even just a few pixels across, with quite low alarm thresholds. They should be situated in areas of the image that are less likely to have motion occur such as high on a wall or in a corner. Should a general illumination change occur they would be triggered at least as early as any Active zones and prevent any other zones from generating an alarm. Obviously careful placement is required to ensure that they do not cancel any genuine alarms or that they are not so close together that any motion just hops from one Preclusive zone to another. Preclusive zones may also be used to reduce processing time by situating one over an Active zone. The Preclusive zone is processed first; if it is small, and is triggered, the rest of the zone/image will not be processed. * Inactive - Suppresses the detection of motion within it. This can be layered on top of any other zone type, preventing motion within the Inactive zone from being effective for any other zone type. Use inactive zones to cover areas in which nothing notable will ever happen or where you get false alarms that don't relate to what you are trying to monitor. Inactive zones may be overlaid on other zones to blank out areas, and are processed first. As a general practice, you should try and make zones abut each other instead of overlapping to avoid repeated duplicate processing of the same area. + Suppresses the detection of motion within it. This can be layered on top of any other zone type, preventing motion within the Inactive zone from being effective for any other zone type. Use inactive zones to cover areas in which nothing notable will ever happen or where you get false alarms that don't relate to what you are trying to monitor. Inactive zones may be overlaid on other zones to blank out areas, and are processed first (with the exception of Privacy zones, see below). As a general practice, you should try and make zones abut each other instead of overlapping to avoid repeated duplicate processing of the same area. + + * Privacy + Blackens the pixels within it. This can be used if you want to hide some regions in the image if the situation does not allow an other solution. This zone type is different to all the others in that it gets processed as soon as possible during capture (even before the timestamp gets into the image) and not in the analyzing process. So if you add, change or delete a Privacy zone, you don't see the changes in the image until the capture process gets restarted. This will be done automatically, but needs a few seconds. Preset The preset chooser sets sensible default values based on computational needs (fast v. best) and sensitivity (low, medium, high.) It is not required that you select a preset, and you can alter any of the parameters after choosing a preset. For a small number of monitors with ZoneMinder running on modern equipment, Best, high sensitivity can be chosen as a good starting point.