One not always have a measure ribbon in the pocket to asses which ball
wins the point , in a 'petanque' or simply called 'ball game'.
Using a feet is not precise and your opponent may argue you are trying
to move a ball ;-) So why not using your Android smartphone to measure the
distance in a few seconds?
Moreover ,only one measure suffices whereas 2 are required in reality.
Manual ball/jack distance measurment , in either realtime camera mode ( faster ) or photo mode ( more accurate ).
Inclination indicator , using smartphone accelerometer.
Installs as a standard Android
application. It will use the active locale (
French or English available ).
Once downloaded from the market , click on the gray ball icon..
Android 2.0 and above , this is not required. Otherwise , you may have
to select the suitable definition for your camera device , as described
( Quick mode )
That's straighrforward, just bend over the jacket and look at the camera image , with a circular ruler drawn on top of it.
- The ruler precision ( number of circle ) can be configured with the button which image has circles on it.
Seldom , you may need to add some offset to the ruler ,while keeping
circle spacing. Just sweep the screen horizontaly with your finger to
- There is also a one circle mode , to adjust the circle like a tangent line.
- Settings will be memorised for the next use. Measurment
( Eagle eye mode )
Most of the time , the quick mode will suffice to rank the balls. If that's not the case, a photo can help if :
- You need a much higher precision.
- Balls are located on the same side of the jack , and quite far from it.
Senior players may have the difficulty keeping the jack aligned while
reading the ruler. A photo will let them adjust witht needing to stay
still while aiming at the jack.
From the 'quick mode' which is the default screen when you open the application , click on the
camera icon ( top right corner ) after aiming at the jack.
Center it as much as you can , you will be able to fine tune with the photo.
Stand on top of
the jack so that the photo does not have perspective errors. Freeze ,
and take the picture by either a click the touchscreen or a click on
the big , general purpose smartphone button.
You should now see the photo in background . By default , non
bouton is active , which means you will drag the closest object to you
Although that usually enough , peoples with thick fingers will appreciate using boutons to do select the right item to adjust.
That is what we are going to explain now. Click on the top left icon ( cross shaped ).You
are in the mode 'aim at the jack' , so the top left icon with a cross
should be activated ( white ). Aim at the jack's center
using either the touchscreen with you finger or the cursor
keys around the general purpose button (Or the corresponding icon
located on the bottom right corner of the screen). Using the
touchscreen is however by far the best user experience.
Once the cross looks aiming at the center , you can still improve
precision , if you like. Switch to zoom mode pressing at the smartphone
general purpose button ( Or bottom right corner icon , as you
like). With any of left hand side icon activated ,
this button swtiches back and forth between zoom mode and
mode. The active mode is visualized by either 4 arrows ( translation )
or a google pair ( zoom ).
Once in zoom mode , you can know zoom with left/righ cursor keys.
Switch to translation again and improve cross alignment with the jack.
unzoom to approximately the initial photo size.
Now that you've just set one extremity of the measure ribbon , click on
the icon to set the second extremity. That is the one with an arc and
Expand the circle utill you reach a ball , that will be the ball
winning the point. This work exactly as before . You can use finger or
buttons , and translation or zoom. Note that you see a small red
'x' on the circle. This is the point you are actually dragging when
adjusting the circle. This helps understanding
visually what happens when you are adjusting an item.
If you like numbers , you can see distance in pixel units in the bottom
left cornet. That is however not required to know which ball wins.
The last icon we did not spoke about allows to move a third fictive
point which is the center of the picture. You can optionaly use it to
look at the scene
ar different points of interest.
measurment system also has the advantage of allowing to readjust a
measure point ( the jack for instance ) without modifying the position
of the second measurement point ( the tangent ball for instance )
Make your measures even more accurate checking you are taking your measure with your phone perpendicular to the ground.
Several visual models included!
the drawing you like through the menu button . Select ' Gauge' , click
on the button that opens a list. Select one, click ok and you are done!.
the handset menu, select 'Score'. A predefined team list will show up.
Choose one on them for your team and udpate your score with the '+' and
buttons. You may reset it to 0 using the button at the bottom.Telemeter
Is the jack too close ? This is the question this tool will help you to sort out.
For the first measurement , the phone needs to know the vertical distance between the phone and the ground.
the icon with 2 arrows , and sweep the screen with your finger to
adjust the height. Hold the position 2 seconds to validate.
, lift your phone in front of your face and aim at the target object ,
pointing at the contact point between the object and the ground. You
must stand on
an horizontal surface for maximum accuracy.
that if you slightly move the camera , it will significantly affect the
measure. To fix this , this telemeter features a magnifier so that you
- Ajust the bounding rectangle around the target object to zoom.
- Adjust the screen size of the magnifier.
is very intuitive , you just have to sweep the screen with your finger
, either horizontaly or verticaly, to adjust either of the 2 parameters.
With legacy phones , ( Android system 1.5 or 1.6 ) ,
this feature may be unstable , due to lack of memory. Its advisable then to only use a small
size for the magnifier , in order to use less memory / cpu.
The magnifier may be disabled by sweeping the screen to the left ( portrait mode ).
Measurment accuray depends on:
- Handsdet accelerometer quality.
Target measurment angle. ( This is a mathematical limitation of
the algorithm ) The farther the object , the worse is the
- How much care is taken to measure the distance.
Your body height is an approximation of the value required, since its
the distance camera/ground which matter. Also do no forget that if
you hold your hands far from your body , your are measuring the distance from the object to your hands, and not to your feet.
may offset those errors by adjusting the height value until you get the
correct value for a distance that you know by advance.
Also, try to have the same posture while measuring.
an example, a 5 cm precision measure could be achieved with LG
optimus phone, at a 1.52m ground altitude , aiming at a target
distance from 3.78 m.
On this phone , precision was much better in landscape mode than in portrait mode ( +20cm accuracy )
good phone calibration may also help . A bespoke method is to move your
phone along a '8' shaped path , with the phone screen facing the ground.
This should be done with ample , slow motion in a location free of intense magnetic fields.
- This application is spyware free , ads free.
- Small memory footprint .
- For Android 1.5 and higher.
- Measure accuracy depends on your smartphone. A relatively
old smarphone with 480*320 pixels, provides a theoretical accuracy of 2
millimeter ( horizontaly ) , ignoring small deformations introduced by
the camera lens. If like some french people you drink too much 'Pastis'
while playing, precision
may decrease dramatically. ;-)