Custom maps crashes with 4 reference points

[Berta Hippe]

Hello Marko,
I have been using custom maps on different Samsung smartphones for 5 years. I am thrilled with this app, as it enables me to safely navigate on very individual bike tours.
Now I've been using a Samsung Galaxy S7 with Android 7 for 3 years. So far, custom maps has worked extremely well on this system.
Since the update to 1.6.2, custom maps crashes regularly when I try to set the 4th reference point while creating the map.
If I save the map after 3 reference points, it works. With only 3 reference points, however, the maps do not have the usual accuracy when navigating. If I try to add the 4th navigation point later, the app crashes again.
What can I do?

[Marko Teittinen]

Berta,

Thanks for contacting me and letting me know about your issue. But it is curious. Your phone is basically more powerful than mine (Nokia 7.2), but I can't get the app to crash by adding a fourth point even though I tried even distorting the map severely. That would indicate there is something special going on in your specific case.

And I don't see any crash reports from Galaxy S7 in my Google Play Store console. So this makes it difficult to figure out what is going on.

Is the map image you are using a very large one, by any chance? This could cause an issue with the phone running out of memory for the app to display the map image over the Google Map. Can you try shrinking your map image to half (just for the sake of testing) and then aligning that? If that helps, then you can try a size somewhere in between the full size and half to get a larger view. But in this case I cannot do much to help you since Custom Maps already tries to use all the available memory Android gives to an app. The amount of available memory depends on the phone and Android version.

Or is it possibly relatively poorly matching Google Maps so that you need to significantly adjust the fourth point to make it match? That might cause some math equation fail when it tries to distort the image with four matching points (it is not always possible to find a linear warping solution between two sets of four points).

If the map image you are having trouble with does not contain any personal information, I would appreciate if you can email it to me, so that I could try reproducing the issue on my own phone or tablet. Feel free to contact me directly (not through this group), if you so prefer and if you see my email address in the header of this message.

Marko Teittinen

[Marko Teittinen]

Update on this issue for everyone on the mailing list.

This bug report helped me discover a crash issue that occurred when starting the process to find the point selected from map image on Google Map. When a relatively "noisy" map image is used, the image samples around alignment points were considered using too much memory by Android, and Custom Maps crashed before showing the screen where one can select the corresponding Google Map point.

I have now fixed the issue and release Custom Maps version 1.7 beta 1 to beta channel in Play Store. In addition to fixing the above mentioned issue, when adding tiepoints (aka calibration points aka alignment points) this version automatically positions Google Map view near the area where the point is expected to be if at least two points have been added previously. Note that Custom Maps does not utilize more than first four tiepoints.

Marko Teittinen

Author of Custom Maps