OpenStreetMap

bri g has commented on the following diary entries

Post When Comment
OSM Art 12 months ago

I was always curious with this particular feature !

http://www.openstreetmap.org/way/24439695#map=12/44.0349/3.2283

problems with GPS traces about 2 years ago

Hi vVvA The JOSM editor is very powerful and there are lots of ways for you to customise it. I have been using it nearly every day for about 3 years - it is very stable, very good.

If you need any assistance with it let me know and I will try to assist you

Best regards

iweua

Beyond First Edits! about 2 years ago

JOSM does have a learning curve you are right, but it isn't that steep especially if you stick to straightforward edits initially. It is incredibly powerful, very stable and since BING imagery ( though we had yahoo before ) very very useful.

I guess an analogy would be the difference between using webmail and an mail client, significantly faster much more application tools and endless methods to customize it should you wish.

Working in urban areas can seem a little daunting to a beginner, so make test edits where it is quiet or no activity and get used to it Also, work in your own area, which you know well. The great this is that the render engine now workd in minutes rather than every wednesday so you don't have to wait a week too see your edits on the web so get some for of feedback.

Also you will find that your first edits with JOSM, especially if you work on areas you know well, you will tend to return to and make even nicer as you become more proficient. So don't worry about making poor edits, you will repair them in due course.

Good luck drop me a mail if you need some assistance

Cleaning Up GPS Traces for OpenStreetMap and Visualizations about 2 years ago

Yep Standard problem - leaving the Garmin on after a hard day, a thousand data points of your desk with a Gaussian distribution of noise roughly resembling a drunken walk - easy fix.

I load all my traces into JOSM with the GPSEdit plugin.

Remove the 'blobs' of data points where I have stopped, or entered a building or whatever, all the obvious noise.

Then merge all the layers down into one and upload as a single GPX

Takes minutes, 'intelligent' filters are unlikely to work so well or so efficiently

Cheers bri Garmin Legend HCX Set to log once / second

What's the story behind these disconnected streets in Lima? over 2 years ago

Quote

'As it is half impossible to align bing aerials without any tracks'

I have no disagreement with this statement at all, may I suggest though that mapping using aerial imagery, even if it is misaligned to absolute co-ordinates is not a waste of time.

In the event that you are newly mapping an area with imagery, but no traces, the whole map could be offset, this is quite true.

You work is not wasted I believe, as within an area, all the roads will be offset by the same amount, and it will just require one upload from an OSM contributor to allow correct alignment the map to the traces, a trivial operation.

So my advice, map to BING imagery, correction and of course all the rich data and corrections that can only be added by people who visit the area, will surely follow.

bri

Relations over 2 years ago

It is tempting to contribute to OSM so that the data, your contribution will 'work' on your GPS / map / computer / browser etc, but Pieren is correct.

The data in OSM should be be the actual data, not a parsed / hacked version that will work on a particular application.

The Map should be factually correct so that applications can parse the data in a uniform way so that it can be displayed correctly on end user apps.

Keep up the good work and keep on collecting and entering the data

bri

New to OpenStreetMap over 2 years ago

There is no doubt there is a learning curve, and procedures to follow. I think the key thing is not to be too worried about making mistakes, particularly if you are working and contributing to a part of the map that needs and will benefit from your input.

The key I found when starting was that one often returns to parts of the map you edited when you were just starting and correct omissions / mistakes that you made as you find out more about the process.

Also, look / inspect with Josm / potlatch high density areas like London where a lot of mappers have worked and reviewed each other's work - look at the data they are adding to POIs, roads etc and follow the examples as best you can.

OSM editing has come a very long way in just a couple of years with JOSM integrating BING imagery, a plethora of free tools for downloading GPS data ( GPS Babel ) , handy tools such as walking papers - free maps for Garmin ( http://garmin.openstreetmap.nl/ ) and all the other devices.

Have fun, ask questions directly to individual members or on the diary / wiki

cheers bri

I'm hooked on this over 2 years ago

There is no doubt there is a learning curve, and procedures to follow. I think the key thing is not to be too worried about making mistakes, particularly if you are working and contributing to a part of the map that needs and will benefit from your input.

The key I found when starting was that one often returns to parts of the map you edited when you were just starting and correct omissions / mistakes that you made as you find out more about the process.

Also, look / inspect with Josm / potlatch high density areas like London where a lot of mappers have worked and reviewed each other's work - look at the data they are adding to POIs, roads etc and follow the examples as best you can.

OSM editing has come a very long way in just a couple of years with JOSM integrating BING imagery, a plethora of free tools for downloading GPS data ( GPS Babel ) , handy tools such as walking papers - free maps for Garmin ( http://garmin.openstreetmap.nl/ ) and all the other devices.

Have fun, ask questions directly to individual members or on the diary / wiki

cheers bri

GPSmap 60CSx Request for advice almost 3 years ago

The Tracklog ( the 10,000 point limit ) on the Garmins is independent of what is stored on the data card. The data card is always storing data at the rate you specify in the menu, eg every 1 second, every 10 meters etc.

The tracklog's only function is to allow you to track back to where you came from. If you set the Garmin to log every second this gives you just under 3 hours of track back time, though this function is not relevant for most mappers. Ignore the Tracklog ( unless you really need it, your data is on the SD card at all times ( so long as you have set the menu to store to card ). You can set the Tracklog to wrap around, or stop at 100 %, either way this does not affect the logs on the SD card which are always being cached at the rate you specify.

Re the saving of tracks, The Garmins use an optimisation / compression algorithm to minimise the size of saved tracklogs reducing accuracy ( for mapping purpose ) so is generally avoided for caching.

Hello! about 3 years ago

Thank you also and keep up the good work - it will be great to see OSM interest and editing work spread more across Europe

Very happy with OSM about 3 years ago

You can generate great GPS traces from cycle tours, I leave my Garmin logging at once per second when touring and generated about three weeks worth of traces around northern Spain last time I had the opportunity. A great memento of my personal tour and useful for OSM once uploaded.
bri

Davos and surroundings about 3 years ago

To check the date of the BING Imagery

http://mvexel.dev.openstreetmap.org/bing/

It seems, JOSM is not "stabile" about 3 years ago

I Have to say JOSM has been rock solid for me for the last two years ( Win xp / 7 ) with no issues at all and very hard to fault. It is the most popular OSM application editor with a large user base. Most of the really obvious problems have been fixed long ago.
Try to think what else might be the problem ( memory / ISP etc ) - My startup is as below - giving JOSM 1 Meg memory which is important especially with Bing - you will note I am using the most recent version and Java 6/26

C:\Windows\System32\java.exe -jar -Xmx1024M "C:\Software\Josm\josm4223.jar"

Note my other posting about uploading in chunks rather than one go in the Advanced tab when you go to Upload

New about JOSM "bug" - it is "silent" ban from OSM? about 3 years ago

JOSM / OSM servers will limit the download of data, thus when I work on Grenoble for example which is highly built up, the maximum area I can download in one go is about 300m square.
All this means is that I must complete a number of downloads to download the town and merge the layers into one if I wish to use the OSM for a custom map - or just set JOSM to download to the same layer.

This is a chore but completely understandable given the amount of data this non commercial server must push backwards and forwards at any given time to the whole community.

I personally tell JOSM to upload in 100 segment chunks, thus a 1000 point upload will go up in 10 sequential uploads ( upload > Advanced tab ) , I have found this to be much more reliable than uploading in one go, especially with big change sets and or if I have inadvertently created conflicts which must be resolved
bri

hope that helps some

Satellite data over 3 years ago

Just to back up previous posts and to explain. Open Street Map is just that, it is about making a OPen Source map that all can use, based on data that has been defined as Open Source by its contributors ( ie OSM editors such as yourself ).

Contributors ( OSM editors ) can use their own data ( GPS Traces, personal surveys of areas etc ) and use data that other suppliers have let us, including Yahoo Imagery and Bing.

The fact that the data starts as open source, means that the map remains open source for all users ( and you sign a license agreement with the website to confirm that you give your data as that ). No one wants to compromise OSM with data that even might belong to someone else ( Google etc ), explaining why the community gets very nervous when ( usually ) a new user suggests they have ( helpfully ) added data from a non open source.

Please keep up the good work and welcome to OSM, and keep us updated on your edits.
bri

Newbee - Accuracy of maps and images over 3 years ago

Yep - all true - BING can be offset, ( I have pre built offsets for Kaduna ( northern Nigeria in Josm, backed up / confirmed by dozens of GPS traces taken over many days ).
Yes GPS can be off, and Garmins sometimes decide to offset themselves for a few minutes by several meters and then re correct themselves.
Really the trick is to have many GPS traces of the same primary highways, uploaded by different users, aggregated over periods of perhaps several years. In this way a fairly good average can be built up, and confirmed by Bing. At least with Bing, the offset will be reasonably constant over a certain area, so once you have an aggregate of GPS traces you can offset the Bing by a reasonable degree.

We should note that if you are using a GPS map derived from OSM, then GPS the user is navigating with will just as likely have a GPS offset, even if the map is 100% accurate, so I guess the word is always caution!

The map is probably about right, how good is ones receiver GPS ?This is possibly why many GPS units also offer the option of locking to map to 'correct' possible location errors.

Is this for real? White spots on the GPS coverage over 3 years ago

More in my diary entry here - white space interference - interesting stuff..

http://www.openstreetmap.org/user/bri%20g/diary/13746

Garmin etrex Vista HCx dead again over 3 years ago

Just another thought, I was thinking that I only ever use batteries to power up my Garmin, but of course I, as all other mappers do, plug it in to the USB port every time I need to download data from it, and never had a problem. The 5V from a USB port is well regulated and extremely unlikely to be overvoltage, which brings suspision in your case,back to the car adaptor.

Garmin etrex Vista HCx dead again over 3 years ago

I have had three Garmins, the original etrex, the legend and now the legend HCX all bullet proof, dropped them, lost them, got them wet, had them hanging off my bicycle, fall off my bicycle ( many times ) all fine
I personally would check your car adaptor which probably cost 20 Euro, used to power up a 200 Euro GPS to deliver 5V via USB. A Small power spike etc from the 12V/5V lighter socket adaptor might be all it takes to destroy internal components.
Garmin UK sent me a free battery compartment cover once when I lost mine (dont ask how), they are good and no, I do not work for them.

problems with GPS traces over 3 years ago

Hi
I downloaded the last two sets of traces that you have uploaded - JOSM was happy with them no issues ( 20110630.gpx & 20110625.gpx ) so not sure what the problem with PL2 if any.

Your traces seem to be a little noisy ( possibly due to being in a built up area ) - and this part of Harvard Campus has excellent BING imagery which will always tend to have a better accuracy than GPS traces and more useful for absolute mapping purposes.

The Garmin Etrex units (depending on which one you have ) have a couple of options on how they store tracks.

The best setting for mappers is to set the units to cache your location every 1/2/5 seconds etc ( I personally cache on 1 second ) using a Garmin HCX Legend with a 2GB memory card. If you have an original Yellow Garmin Etrex, you will not have this option, and you are stuck with the Garmin caching technique, that when it detects that you have made a significant move from your last cached point, or are making a direction change. it is an efficient approach in terms of data storage, but can lead to rather untidy tracks especially when you are walking.

To Clean up GPX tracks before uploading can sometime be useful, especially if you have left the GPS unit on ( perhaps at home or work ) and you find a large cluster of noisy points etc. I usually drop my GPX tracks into JOSM and use the plugin EditGPX to tidy up a trace before upload. You can also merge a number of tracks down into one layer thus saving you multiple uploads of smaller GPX tracks.

You have highlighted a another problem - but I think that needs a new Diary entry
Good luck and enjoy making your traces - have a play with JOSM and some of the plugins, I am sure you will find them useful