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שפות זמינות — FAQ
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Frequently asked questions


?OpenStreetMap למה

?OpenStreetMap למה אתם עושים את

מידע גיאוגרפי אינו חופשי בהרבה חלקים בעולם, כולל בישראל בריטניה ורוב אירופה. בדרך כלל משימת המיפוי במקומות אלה ניתנת לגופים ממשלתיים שבתמורה מרוויחים כסף ממכירת המידע בחזרה לך ולי. ארה"ב, בניגוד לכך, היא המדינה הגדולה היחידה שבה הממשלה חייבת לתת את המידע בחינם בגלל הגבלות זכוחות יוצרים שחלות עליה

אם אתה חי במדינה כזו אתה נאלץ לשלם על המידע פעמיים. אתה גם מממן את המיפוי עם כספי המיסים וגם משלם כדי לקבל עותק מתוצאות המיפוי

בדרך כלל המידע שאתה מקבל אינו משתנה הרבה עם הזמן, כבישים לא נוטים לזוז מתוך שעמום, וניתן לנווט באזורים רבים בעזרת מפות מלפני שנים.

הנתונים שאתה מקבל כוללים שקרים ושיבושים מכוונים במטרה לתפוס מעתיקנים. שיבושים מכוונים אלו באים לידי ביטוי ברחובות מזויפים או חסרים או מבנים כמו כנסיות ובתי ספר שאינם קיימים במציאות. אם אתה מכין מפה תוך שימוש בנתונים שלהם הם יכולים לצעוק "תפסנו אותך" אם הם רואים שהעתקת גם את השיבושים. המפה עלולה גם להיות סתם שגויה בגלל שהיא ישנה ודרכים חדשות נסללו או פשוט בגלל שמישהו עשה טעות

אם אתה מסכים עם המצב הזה, אתה לא יכול לעשות הרבה עם המפה חוץ מלצלם אותה. בהרבה מקומות גם זה לא חוקי אם אתה חורג מעבר ל שימוש הסביר (או הטיפול הסביר) אינך יכול לתקן שם של רחוב או להוסיף פאב מעבר לכביש, או להשתמש בנתונים בתוכנית מחשב מבלי לשלם כסף רב. יותר כסף ממה שכנראה יש לך. מה לגבי לשלוח את המפה לחבר, להוסיף אותה להזמנה או לפרסם אותה על איזה לוח? רוב הדברים האלו פחות חוקיים ממה שנדמה לך

זולות, אתה יכול היום ליצור מפות בעצמך, בשיתוף פעולה עם אחרים GPS בעזרת ההתקדמות הטכנולוגית, שמאפשרת למשל יחידות ולהמנע מההגבלות הנ"ל. היכולת לעשות זאת מאפשרת לך לזכות בחזרה בחלק קטן מהקהילה שבה אתה חי - אם אתה לא יכול למפות אותה אתה לא יכול לתאר אותה

Why don't you just use Google Maps/whoever for your data?

Short answer:

Because that data is copyrighted and owned by people like the Ordnance Survey. Google/whoever just license it. If we used it, we'd have to pay for it.

Long answer:

Most hackers around the world are familiar with the difference between "free as in beer" and "free as in speech". Google Maps are free as in beer, not as in speech.

If your project's mapping needs can be served simply by using the Google Maps API, all to the good. But that's not true of every project. We need a free dataset which will enable programmers, social activists, cartographers and the like to fulfil their plans without being limited either by Google's API or by their Terms of Service.

At this point, the usual rejoinder is "Why don't you just get people to click a point on a Google map, then record the latitude and longitude in the Openstreetmap database? That's free, isn't it?"

Unfortunately not. The data used in Google Maps is sourced from NAVTEQ and Tele Atlas, two big mapping companies. They, in turn, have obtained some of this data from national mapping agencies (such as the Ordnance Survey). Since they've made multi-million pound investments in gathering this data, these organisations are understandably protective of their copyright.

If you collect data from Google Maps in this way, you are creating a "derived work". Any such data retains the copyright conditions of the original. In practice, this means your data is subject to the licensing fees, and contractual restrictions, of these map providers. That's exactly what Openstreetmap is trying to avoid.

Please don't be misled by considerations of software copyright, or of Terms of Use. The Google Maps API can be incorporated into open source projects, sure. But this only governs how you use the software - it doesn't have any implications whatsoever for the data displayed by this API, which is still under copyright.

(It's not yet clear whether it's ok to create a derived work from aerial photography: some readings of UK law suggest that you can do this without 'inheriting' the copyright in the photography. A definitive ruling on this could open up new avenues for Openstreetmap and similar projects, but in the absence of such a ruling, we're continuing with the approach of sourcing our own, 100% independent data.)

Further reading:

  • Google Maps' Terms of Service. Note particularly the 'Map Information' section, and that:
    • "Geocoding data for map content in Google Local is provided under license by Navteq... and/or Tele Atlas... and subject to copyright protection and other intellectual property rights owned by or licensed to NAVTEQ, TANA and/or such other third parties."
    • "Also, you may not use Google Local in a manner which gives you or any other person access to mass downloads or bulk feeds of numerical latitude and longitude coordinates."
  • The Openstreetmap mailing list archives. You may want to search them for phrases like "derived works", and for a thread in October 2005 called "London locations".
  • For UK users, here's a useful PDF of copyright legislation.

How can a project like this create accurate maps?

By the very nature of the wiki-style process there is no guarantee of accuracy of any kind. Then again, few proprietary maps carry a guarantee of accuracy, either. In fact, some have artificially-introduced errors.

The essence of a wiki-style process is that all users have a stake in having accurate data. If one person puts in inaccurate data, maliciously or accidentally, the other 99.9% of people can check it, fix it, or get rid of it. The vast majority of good-intentioned participants can automatically correct for the few bad apples.

And as they say, your mileage may vary. The Wikipedia project has shown that a large amount of good quality data can be collected but it can be difficult to weed out the inevitable errors.

Currently there are no processes or mechanisms, such as recent change lists and watchlists, that can be used to easily monitor edits within OpenStreetMap. We do however store a full editing history, and so these mediating processes will be developed as soon as they become necessary.

At the moment the best way to answer this question is to judge for yourself. One way is to pick an area that you know well and use the OpenStreetMap viewer to see how well the map data corresponds to your own knowledge. Maybe you will see something wrong or inaccurate. More likely you will find there's nothing there yet. At this stage, our main challenge is to extend our coverage, without copying from existing maps. As on Wikipedia, it's easy to edit, so you can help!

You seem to have a lot of existing map data. Where did it come from?

We have a lot of very keen contributors!

We are also bringing in TIGER data for the US (in progress), and we have AND Data for the Netherlands (kindly donated), and we are always on the look out for other Potential Datasources. However, all of our data must come from public domain or open licensed sources which are compatible with our OpenStreetMap License. Even in those areas where free data exists, there is generally a lot of room for improvement via our wiki-like community map editing process.

In areas where there are no such data sources (most areas) we have to start from a blank slate, and head out there to survey the streets ourselves. Despite starting from scratch, we have achieved a good level completion in many places.

Why is the data sometimes inconsistent?

"OpenStreetMap is a free editable map of the whole world. It is made by people like you." Which means the database will always be subject to the whims, experimentation, and mistakes of the community; this is precisely OSM's strength since, among other things, it allows our data to quickly accommodate changes in the physical world.

למי שייך OpenStreetMap?

לך. הנתונים והתוכנה שייכים לך, ולכל התורמים.

קיים ארגון בשם קרן OpenStreetMap שקיים כדי להגן, לקדם ולתמוך בפרויקט, אבל הוא לא הבעלים של הנתונים.

What does your licence allow me to do?

We have a Legal FAQ which will give you some pointers, but it's not definitive and is the subject of some debate. As of late 2007, the OpenStreetMap Foundation is considering licence issues and hopes to have progress to report early in 2008.

?איך אני יכול לעזור

?איך אני יכול ליהיות מעורב

.Openstreetmap יש דרכים רבות לתרום לפרויקט

אתה יכול להשתמש בה כדי לאסוף נתונים GPS אם ברשותך יחידת

ולהשתמש בכלים המקוונים שלנו כדי להעלות אותם למאגר

אתה עדיין יכול לעזור גם אם אין לך יחידה כזו. רשימת הדרכים לעזור נמצאת בדף הזה

?איך אתם מתקשרים

The OpenStreetMap community is large, and spread across many locations, speaking different languages, and focussing on different interest areas. So the answer is we don't always communicate very well! But we do our best.

We have various Contact channels.

See Contact for more information

?האם אני יכול להפגין את תמיכתי בעזרת רכישת פריטים מגניבים

כן! תראה איזה דברים מגניבים מוכרים בחנות


?OpenStreetMap איך אני יכול לעזור ל GPS יש לי נתונים מ

You can upload your GPS tracklogs to OpenStreetMap, so that you and others can trace over them to draw maps. You'll need to be a registered OSM user before you do this. See tracks that others have uploaded.

Once you've done that, you can use the GPS as a guide to drawing roads and paths for OpenStreetMap. You can do this by:

  • edit your data online, using Potlatch, an easy-to-use Flash program that runs within your browser; or
  • edit at home using JOSM, which provides a powerful way to edit GPS data locally on your computer into sensible tracks before uploading them to the server (there are other editors, too);
  • and if you don't have a GPS you can still help, see Getting Involved.

I have public domain non-GPS data, how can I upload it?

For public domain data obtained from non-GPS sources (for example, a municipality's public information website [be sure to confirm that the data is in public domain] or other public records), it's easiest to use the OSM Protocol Version 0.5 API. A worked out example: Using curl to upload data

What images and maps may I use to make maps from?

Most maps have copyright restrictions. This includes images from "free beer" sites as Google Maps, and printed paper maps, even if you scanned them yourself. Commercial aerial/satellite photography is also copyrighted.

You should not use copyrighted maps in any way while editing OpenStreetMap (unless it is compatible with our license). "Using" includes tracing over the map, copying a name from the map, or pinpointing a coordinate on the map. To be on the safe side, we tend to regard all of these as a form copying, or "creating a derived work". Generally speaking, it's best not to even look at copyrighted maps while you are editing OpenStreetMap.

So what can you use? Not very much, which is why we are doing all this re-surveying from scratch. However there are some Potential Datasources, in particular we have imported TIGER data for the US, AND Data for the netherlands. We also make use of out-of-copyright maps although they are very old, and Yahoo! Aerial Imagery (which we have special permission to trace over)

?עשיתי עכשיו כמה שינויים במפה, איך אני יכול לראות אותם

Because OSM users make so many changes to the map, it's updated on a periodic basis, rather than immediately after you edit it.

The "tiles" that make up the default map (the Mapnik layer) are updated every Wednesday. In order to make sure the update process notices your changes, after editing an area, try to view the map for that area. This will flag the area to the rendering software.

If your data is still not appearing and you are pretty sure that the one or the other renderer has done its job, then you might have a tagging problem. Check that:

  • all your ways are tagged with something appropriate that will be rendered (eg highway=unclassified)
  • your tags are in lower case: HIGHWAY and Highway will not work.

?מה אני אמור לעשות עם כביש שיש לו מספר ערכים שונים כתוויות

Separate the values with semi-colons - e.g. nat_ref="B500;B550" for a road that is both the B500 and the B550 at the same time. For nodes (points) with two tags, though, use commas instead of semi-colons.

?מה משייך כביש לעיר

This is often asked by beginners. There should be a closed way marking the extent of the city with a "place"- and a "name"- tag as well as a single node with a name and place to mark where to draw the city-name. In the actual map such a shape does not exist for many cities, thus only the distance to the node that marks the city can be used in these cases. For exceptional cases an is_in can be used.

Another user has changed something I drew. I think they're wrong. How do I contact them?

To find the name of the user who edited it, select the way and press H in Potlatch (then click 'Cancel'), or click the way in JOSM and look in the appropriate panel.

You can then go to their user page, which for a user called Fred28 would be at https://www.openstreetmap.org/user/Fred28 . Click "Send message" to send them a message.

(This will not work if the user has chosen to be anonymous - find out more.)

Editing with Potlatch

See the separate Potlatch/FAQs page.

(Potlatch is the map editor that you get when you click the "Edit" tab on the main site. If you don't know which editor you're using, it's probably Potlatch!)

Editing with JOSM

I tried to download my town/city/region - why doesn't it work?

Chances are the area you tried to download is too large, and the server probably timed out before getting the data to you. Try on a very small area first to make sure its working OK. If thats ok, then you are best to download the town in smaller segments. Presently, you cannot download an area larger than 0.3 degrees in either dimension.

If you really want large areas of data, the best approach would be to download the planet.osm file, which is generated weekly. This file is basically a snapshot of the OSM database and contains all valid data.

I want to create a very long way - how do I download OSM data for such a big area?

In order to be able to easily handle long roads, you should not make ONE long road out of it. You should rather split the road into several ways. As a rule of thumb, no way should be longer than 10-15 km. Typically, they will actually be much shorter.

Applications like route planners for example will be able to easily join the ways to one road again. This type of applications will need to postprocess the OSM data anyway.

For motorways for example, it makes sense to make a way from one exit to the next. Also, intersections of motorways should be the point where you split a road into ways.

Why doesn't my login work?

There are two different logins for the OSM project: one is for this wiki only, and the other is for the website, API and forum. You need to register on the www registration page to actually be able to work with OSM data.

GPS שימוש ב

?שהעלתי לא עלה כמו שצריך GPX למה קובץ ה

Your GPX should consist of trackpoints with valid timestamps. The ele(vation) tag is optional and will default to 0. Something like below is acceptable:

<?xml version="1.0"?>
creator="GPSBabel - http://www.gpsbabel.org"
  <name>ACTIVE LOG</name>
<trkpt lat="52.564001083" lon="-1.826841831">

There are two things the importer won't do. First, it won't take in GPS points without timestamps as they're to be used to work out speed and so on. The other is that it doesn't import waypoints and your file consists only of waypoints.

The reason for this is that if you reset many GPS units or download map data to them, then you often get copyrighted data put in the GPX. The most famous example is that if you reset a Garmin GPS unit then it will put the locations of the Garmin offices around the world as waypoints on the unit.

?למה הנקודות במסלול שלי מרווחות מדי

This is due to the GPS device (usually a Garmin) being set to record on 'Auto', which saves space by recording fewer points on straights. It's not usually a problem in rural areas, but isn't much use for city mapping. To make the gps record more points, go to the track settings menu on your GPS, and change the recording method to either 'Time', or 'Distance'.

Time: Time will record points every 'x' seconds/minutes/hours. This can be changed on some gps devices. Having this setting will use up the memory fast, but will increase the points considerably. The disadvantage of this method of saving is that when moving slowly with the GPS device the points will become densely packed.

Distance: Distance will record points every 'x' Meters/yards. This can be changed on some gps devices. Having this setting will use up the memory fast, although relative to your speed. The disadvantage of this method of saving is that when traveling on straight roads fast, (motorways/highways), unnecessary points will be recorded. Also if you are to be tracking a small area, if the 'x' value is too high, your route will be unclear.

Wrapping: If the option is available to turn on, or off the wrapping function, then having it off is also advised. Having wrapping on means that when full, the gps device will make room to record the latest section of your route, by deleting the tail of your route. It will delete the tail, point by point, at the same rate as new points are created. The exception would be when you are logging track data to a data card in some Garmin models. The tail data will be deleted from the device's built in memory, but not from the data card.

Why do I get bad signal / traces in city centers / near big metal buildings?

For a GPS to work and achieve some accuracy it needs to receive at least three satellite signals. Often when in city centers there are many tall buildings that can block these signals and stop the GPS from being able to work out where it is. There may also be multi-path effects from the material making up the buildings around you, whereby signals bounce off them so the receiver actually thinks it is somewhere in the buildings around. Another factor that can affect this is the number and position of satellites that can be seen at the time of logging; trying the route on another day may give better results.

What GPS should I buy? Can I use a "satnav" in-car unit?

See GPS reviews. Some in-car units will generate the tracklogs that OSM use, but you must make sure you turn off the "Snap to Road" option - otherwise your tracklog will be linked to the copyrighted map in your satnav.

שימוש במפות והנתונים של OSM

?מהאתר שלי OSM איך אני מקשר קווי כתובת ספציפית במפת

You can link to the search page for a particular postcode:


?מהאתר שלי OSM איך אני מקשר קווי אורך ורוחב ספציפים במפת

You can link to the slippy map with a specific latitude and longitude and zoom level:

https://www.openstreetmap.org/index.html?mlat=[latitude in degrees with decimals]&mlon=[longitude in degrees with decimals]&zoom=[zoom level 1-17]

Or link to a static image

שאלות מפתחים

Why should I not begin development on a new editor, one better/different/prettier than current editors?

There are already several very useful OSM editors in development, and confusing the space with "yet another" platform will only duplicate effort. Please consider contributing to one of the editor development efforts already in progress, such as JOSM, Merkaartor, or Potlatch.

?למה אתם לא מחלקים את העומם של בסיס הנתונים בין כמה שרתים

Sharing the OSM server load via MySQL replication, or BitTorrent, or carrier pigeon is often recommended, but the idea has so far gained little momentum -- in terms of real development effort. If you have the system administration or coding expertise to implement such a distributed system, please do not hesitate to volunteer on the mailing list.

As a starting point, you may want to familiarise yourself with the existing software infrastructure, as described in the Development pages.

?אני חושב שגיליתי באג. מה עלי לעשות

If you find a problem with the map editing applet or the website, add it to the OpenStreetMap bug tracking database. We use trac, which uses your OSM username and password.

If you notice something incorrect/missing/wrong/unintelligible with the documentation you're reading right now, edit it! It's a wiki! For wiki advice and extensive documentation, see the mediawiki project, who created the software this wiki is running on.

(מערכות מידע גיאוגרפי) GIS שאלות מאנשי

What geographic datums are used in OpenStreetMap?

OpenStreetMap uses the WGS-84 lat/lon datum exclusively. All uploaded tracks and edits should always be in WGS-84, the default datum for GPS receivers.

What is the map scale for a particular zoom level of the map?

The following table shows the nominal scales for each zoom level. Data from http://labs.metacarta.com/osm/

So, for example the nearest equivalent to an OS Landranger map at 1:50,000 is zoom level 13 (nominally 1:54,000).

Note: figures are rounded to millions from levels 8 to 2.

Table of Levels/Scales
Zoom level Scale as representative fraction Approximate meters per pixel
18 1 : 1,693
17 1 : 3,385
16 1 : 6,771
15 1 : 14,000
14 1 : 27,000
13 1 : 54,000
12 1 : 108,000
11 1 : 217,000 12.23
10 1 : 433,000
9 1 : 867,000
8 1 : 2 million
7 1 : 3 million
6 1 : 7 million
5 1 : 14 million
4 1 : 28 million
3 1 : 55 million
2 1 : 111 million

Why aren't you using Open Geospatial Consortium (OGC) schemas and software for OpenStreetMap?

There are many existing tools which people often recommend for OpenStreetMap to use. The problem is, most of them are hard to use and maintain for a variety of reasons, and people are very reluctant to volunteer to help set them up and run them. We used to use MapServer for serving static versions of our maps, but unfortunately we found it to be unthreaded, slow and hard to extend - we replaced it with mapnik.

It's not that OpenStreetMap as a community is against OGC standards, but OpenStreetMap has been built iteratively using the simplest approach that could possibly generate useful maps. The focus is on street data and maintaining a 'wiki' approach to editing where all changes are logged and can be rolled back. Off the shelf tools don't support that in the way we'd like.

Help is needed on choosing which OGC tools and standards to use, and integrating them effectively into our existing systems. Please get in touch if you can spare the time and expertise to do this.

Also, see Why not GPX for a similar discussion about why GPX was rejected as a transport format.

Why don't you add OSM support to existing products, rather than writing your own route-planning program?

RoadMap is a promising PDA and desktop navigation software, which is open source and uses TIGER for US data, and (as of 2006) vmap0 data for the rest of the world. The RoadMap trunk does not yet support autorouting, but has speech synthesis (for street names, etc). Ehud Shabtai's FreeMap fork of RoadMap which is in active development, has support for autorouting and has been ported to PocketPC and J2ME mobile phones in addition to the systems supported by RoadMap. It also has an interface which is more adapted to the small displays on mobile phones and PDAs.

Roadnav is another valid alternative, although contrary to RoadMap it offers no PocketPC support as of yet, and only supports TIGER data, although Digital Chart of the World (DCW) support is planned. It does support autorouting, however, and 3D views and aerial photos (wow!). The newest release of Roadnav has preliminary OSM support.

traveling-salesman is a rather new one. Mostly interesting for java-developers at this point.

I have geo-referenced photography/shapefiles/waypoints for my area, how can I upload them?

We'd love your high resolution geo-referenced aerial photography/satellite images if they are free of copyright restrictions for derived works, or you are the copyright holder and can grant us the relevant rights. Unfortunately we don't have a clean and simple way to add extra imagery yet, but please get in touch via the mailing list and we'll let you know when we do.

The situation is the same for shape files and other data formats - we're definitely interested to hear from you, but we won't be able to add things immediately, yet.