Timelapse and Webcams

Images for timelapse movies can come from a variety of sources, not just your camera set up on a tripod somewhere. For example the internet is full of webcams streaming out their images 24/7 and they can make for some entertaining results. It’s also an easy way of grabbing a lot of different types and quality of images to hone your processing and production skills. The movies are obviously restricted by the refresh rate of the webcams which is not likely to be less than 10s but they can still be entertaining.

Note: The question of copyright of streaming webcam images is a complex one. According to Wikipedia and to a document written by a Swiss legal firm the question is largely untested in law and it’s likely that a webcam would fail the originality / individual character part of the copyright protection requirements. However IANAL so please take your own precautions especially if you intend using these images commercially. In any event I would strongly suggest that you contact the owner of the webcam to see if they’re happy with what you’re doing.

Thanks to the kind people at the http://www.bs.ch/ website for letting me use their webcam images to create the following example:

Accessing the Webcam Images

The technique described below will not work on all webcams. It will work on those websites that use a single URL to a webcam image that is updated each time a new image is captured. Other webcams use different libraries and I’ll discuss one of these in a future post, others still use Flash which is most definitely not in scope here. ( Flash will be gone by 2020 and, frankly, nobody will miss it )

It’s easier to describe with an example. The city of Basel in Switzerland has a couple of interesting webcams which are accessed by clicking the webcam link on the top of the page. ( Note that the slide down to display the two webcam images only works if the “DE” language is selected, I’m not quite sure why, maybe a localisation issue? )

Clicking on one of these images, e.g. the Barfüsserplatz, brings up a popup with the latest image shown in it. This image will auto-refresh every 15s as stated at the bottom of the popup. ( If the image refresh rate is not stated on a site then staring at the screen with a stop watch and clicking “refresh” every 5s is probably the best approach )

Right click on the picture and select “view image” will show the latest image in a new window. The URL is similar to:

http://zid.abel-systems.ch/webcam1/webcam.jpg?r=1502222620002

I think that the number at the end is some form of serial number, possibly with the Unix timestamp included in there somewhere. However as we don’t know how many images are stored on the server or how long they’re kept for then trimming the URL to:

http://zid.abel-systems.ch/webcam1/webcam.jpg

shows just the latest image. By clicking refresh every 15s we can see the new images as they arrive.

The city of Verona also has some similar webcams – http://webcam.comune.verona.it/index.html

Image Download Script

Gathering the images for a timelapse movie by repeatedly clicking “refresh” and right click “save image as” is entirely possible if a little tedious. It is of course much easier with a script built around the wget utility. As with all these command line tools there’s a multitude of options but we’re looking to create something like the following command for each image. The file names should of course increment sequentially to make the movie creation easier.

wget --output-document=path/to/file/file.jpg sourceURL

I’ve written a small script together with a configuration file and these can be found in my GitHUb repository – https://github.com/john-davies/Blog-code-files ( webcam_timelapse_script directory )

The script is run as follows:

./webcamfetch.sh config.cfg

There are 5 configuration values:

  • frame_count – number of frames to capture
  • frame_interval – interval between frames in seconds
  • url – location from which to fetch the image
  • store_location – directory on local disk where the downloaded images are to be stored
  • file_prefix – extra fixed text to be added on the front of the file name

The script does some brief sanity checks then just loops around the set number of times fetching and storing the images. Note that there is no error checking, if any downloads don’t work for any reason then the resulting movie is likely to be not much use anyway.

After the images have been downloaded then I follow my normal timelapse workflow. For the following example, captured from the Basel webcam, I just ran the deflickering script and created the movie as shown in the example above.

Although its quality is not HD standard it’s pretty good and there’s a lot going on in the scene:

  • the movement of the shadows and the few clouds are very obvious
  • the movement of the crane in the background and the traffic/trams would be better at a lower refresh rate
  • towards the end of the movie, as the sun hits the wall of the white building in the centre of the scene then the automatic blinds are triggered
  • towards the top left there seems to be an external lift on one of the buildings which you can just see going up and down
  • I like the timestamp at the bottom of the image, it gives a good sense of the time passing
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Ruhpolding and the Bavarian Alps

If you mention the name of Ruhpolding to any winter sports enthusiast then they will immediately think of the World Cup Biathlon competition that is held there every year. But while Winter sports are still an important tourist attraction for the area there is an increasing emphasis on Summer visitors as well. As might be expected the terrain makes for great walking country especially as the cable cars and ski lifts are open all year round so the ascents are not too brutal! However as the town is close enough to most other places of interest in southern Bavaria then it’s a great base for a variety of holidays.

Getting there, accommodation and getting about

Location

Ruhploding sits in a valley in the Chiemgau Alps in southern Germany not far from the border with Austria. Like many Alpine towns it was originally agricultural but these days caters mainly for tourists, both in Summer and Winter. Despite the rural location it’s well connected with easy access to the A8 autobahn and also to international airports at Munich, Innsbruck and Salzburg. The main rail line from Munich to Salzburg calls at Traunstein where there is a branch line to Ruhpolding. The weather is typical Alpine and so can change very quickly and from day to day. We spent a week there and had the full range of blazing hot sun through to damp, cold and rainy.

Accommodation

Accommodation is mainly hotels or the occasional chalet. We booked an inclusive
holiday from Thomson’s Lakes & Mountains brochure and flew into Salzburg which is a 45 minute drive away. All the hotels seemed reasonable but we picked the Hotel Steinbach   because it seemed to offer the balance of being close enough to the town centre without being slap bang in the middle. Most of the accommodation caters for both Summer and Winter and the Steinbach rooms were very comfortable with twin beds, en-suite and a separate sitting area. The hotel also had a “Wellness Centre” which contained a swimming pool, jacuzzi, steam room, sauna etc. This was very relaxing after a hard day sightseeing or on the odd wet afternoon.

Local transport

As is common with tourist areas like these every visitor gets a discount card – the Chiemgau Card in this case. The link gives details of the offers but the main attraction to us was free local bus travel and free travel on the rail shuttle between Ruhpolding and Traunstein which makes getting about cheap and easy. Going further afield means changing trains at Traunstein or catching a regional bus to places like Salzburg, both of which are straightforward.

Things To Do And See

Town

Ruhpolding itself is a small town geared mainly towards tourism. The town centre contains the usual array of shops, cafes and bars but night life is minimal. For lunch we mostly frequented the Schuhbeck café as the coffee and the food was good and reasonably priced. We were there during the 2014 World Cup in Brazil and on the days that Germany played the café staff were all dressed in replica German shirts with “Schuhbeck” on the back. You can do that sort of thing if you’re confident of winning – or at least getting out of the group stages 🙂 ( The gents toilets in that café were also rather surreal. )

There are inevitably several local history museums. Being interested in all things wood one of our favourites was the lumberjack museum – http://www.holzknechtmuseum.com/ – which documents the local history of forestry and wood cutting. It’s outside the town but close to Biathlon Arena ( see below )

The very ornate interior of the local parish church – Pfarrkirche St. Georg – is worth a quick visit and you get a good view over the town.

 

Biathlon Arena

Practice on roller skis during the summer

Having watched the biathlon competitions from the Chiemgau Arena many times on television then a visit to the stadium was high on our list. The stadium is a couple of miles outside the town but easy to get to on the bus. Tours are free and take place on two mornings a week, check details with the tourist office. They start on the grandstand, deserted at this time of year, but normally home to thousands of well lubricated fans from around Europe.

The tour commentary is in German but I managed to follow most of it even with my very limited vocabulary. Two facts that I didn’t know were, although they have snow cannon, they also collect and store snow in a big insulated shed over the summer to get a head start on the new season. Also they have a ski jump so could host Nordic Combined World Cup events but they haven’t done that since 2007.

Point this end at the target …

After the tour, which lasts about an hour, there’s a chance to have a go on the World Cup shooting range. You have to pay for this but we jumped at the chance and after a very short briefing session from the instructor – ex Olympic gold medallist Fritz Fischer – we were good to go.

I was a bit apprehensive because my wife has, in the past, won prizes and medals for air rifle shooting while I tend to be a bit erratic. However this time honours were shared and we both got 3 out 5 which earned a thumbs up from Fritz and an autographed postcard as a prize. Altogether a very enjoyable morning and our favourite activity of the trip.

Outdoor sports

There are many opportunities for walking, either Summer or Winter, around Ruhpolding. The town’s website has list of suggested walks  of varying degrees of difficulty but there are many others. The local tourist office sells a map with all the local footpaths listed. The Chiemgau Card gives some free rides on the Rauschberg cable car or Unternberg chair lift  and these can be used to advantage as part of a longer walk.

Left is a view of Ruhpolding from the top of the Unterberg mountain ( we took the ski lift
up and walked down )

One of our favourite walks was alongside the Traun river towards Traunstein. The railway also runs alongside the river so it’s possible to combine a one way walk with a train ride the other way.

The town’s website gives details of the cycling opportunities available. We didn’t try any of these but there are plenty of marked mountain bike trails for different abilities. Bikes could be borrowed free of charge from the hotel.

Other Summer sports available include golf or paragliding. A couple of the guests on the same holiday were keen golfers and spoke very positively about the local course. There’s also a swimming pool and water park in the town which is free via the Chiemgau Card.

Nearby towns & cities

Salzburg

View across the river Salzach with the Schloss Mirabell in the background

Salzburg is most famous for being the birthplace of Wolfgang Amadeus Mozart. Its second most famous claim to fame is that it was the setting for the film The Sound of Music and, needless to say, you can go on city tours dedicated to both of these. However if you look beyond then Salzburg has other attractions that are less well known but just as interesting.

When we were there the Chiemgau Card gave a discount on bus travel from Ruhpolding to Salzburg with a return ticket costing 5€.

We wanted to look round the Salzburg Museum but unfortunately, for some reason, it’s closed on Mondays even in the Summer. However the DomQuartier museum and cathedral complex is excellent and gives an insight into the complex religious history of the city.

Slightly out of the town, right next to the airport, is Hangar 7. Essentially this is where Red Bull keeps its toys and it contains a variety of cars, planes and other desirable gadgetry – see
photo gallery below. It’s possible to reach it by bus from the city centre but we visited on a different holiday when we drove to the region. Entrance is free and there’s free car parking just outside. There’s also an award winning restaurant but, as we couldn’t see any prices, we decided that it was in the “if you have to ask …” category and ate elsewhere 🙂

Munich

Munich is about an hour away by train and you can buy tickets on the shuttle train from Ruhpolding to Traunstein. We didn’t get round to visiting Munich during our holiday but it’s a fascinating city, and probably merits a week’s holiday just by itself.

Traunstein

Arches near the church of St. Georg und Katharina

Traunstein is the town at the other end of the railway branch line from Ruhpolding. It’s fairly small but St. Oswald’s Church in the Market Square is interesting and has a bust of Pope Benedict XVI commemorating his links with the local area. The Stadtplatz square also has a large shop selling the strange shaped brass instruments that you only seem to find in German oompah bands. I would have loved to go in and inspect them in more detail but I feared that my German language skills were not up to that level of discussion 🙂

Further afield

Any good guidebook to Bavaria will list many additional attractions and likely places to visit. We felt that there was enough to keep the visitor occupied in and around Ruhpolding but two other popular destinations are:

  • Berchtesgaden – an area in the southern Bavarian Alps, these days most famous for Adolf Hitler’s former residence, the Berghof, in Obersalzburg. Organised tours usually include a boat trip on the nearby Königssee.
  • Lake Chiemsee – a huge freshwater lake with several islands that can be visited, including one which has a palace built by King Ludwig II meant as a replica of the Palace of Versailles

 

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