Travel route animation: Duration setting

terrypin wrote on 2/8/2014, 6:40 AM

The duration of an animation doesn't seem consistent with the 'Duration in sec' time shown.

If a reasonable number such as 12 s is entered then the animation takes twice that. Probably a bug.

If that is increased to say 15, then the actual is again twice that, 30 s.

If that is then reduced to say a rather unreasonable 4 s then it takes 12 seconds, inconsisent with the doubling 'rule'.

From trials I'm guessing there's an (undocumented) lower limit of a 12 s animation minimum. Of course, you could always speed it up if you had an impatient audience in mind.

--
Terry, East Grinstead, UK

Comments

browj2 wrote on 2/8/2014, 11:21 AM

Hi Terry,

I don't get the same result. If I ask for 15s I get 19s, for 20s I get 24s. I noticed that the frame rate was 26fps, whereas my movie was 29.97, but that did not seem to affect anything. For me, there is a 2s delay at the start and end, and the route takes the time specified.

Why you get double I don't know. Could it be the frame rate change?

terrypin wrote on 2/8/2014, 12:56 PM

Thanks John, appreciate your taking the trouble to check.

I should have added that these routes were all made automatically
using the facility to import GPX files.

And subsequent tests seem to imply that the situation is even more
complex than I'd thought. For a 12 mile walk the animation took no
less than 55 s, with the Duration box set to 5 s! I'm guessing the
minimum length is related to the number of trackpoints in the GPX
file. Once there are about 200 trackpoints no obvious rules seem to apply.

Another 16 mile walk with 483 trackpoints, set to a duration of 5 secs took 90 seconds to play.

--
Terry, East Grinstead, UK

johnebaker wrote on 2/8/2014, 6:06 PM

A thought - is the actual length of the animation related to the number of trackpoints in the GPX files and not the desired set duration?

John

terrypin wrote on 2/9/2014, 2:53 AM

Hi

A thought - is the actual length of the animation related to the number of trackpoints in the GPX files and not the desired set duration?

John

Er, see my last post!

Terry, East Grinstead, UK

johnebaker wrote on 2/9/2014, 10:50 AM

@ Terry

I did - that is what made me ask because there appears to be some information missing.

. . . . For a 12 mile walk the animation took no less than 55 s, with the Duration box set to 5 s. . . .

Yes - but how many points in the file?

. . . . Another 16 mile walk with 483 trackpoints, set to a duration of 5 secs took 90 seconds to play. . . .

Have you tested the relationship with 32, 64, 128, 192, 208, 224, and 240 points - if my hunch is correct there is a relationship.

John

terrypin wrote on 2/9/2014, 12:11 PM

Hi John,

Yes, I'd tested 7 GPX fies before my post. Number of trackpoints was roughly proportional to the length of the walk. I've since tested one more as described at end of my last post in the Vasco de Gama thread
http://www.magix.info/uk/vasco-da-gama-travel-route-animation-example.forum.1067701.html

(See the interesting point there about the exported WMV versus the TRA durations.)

**Animation duration v trackpoints for GPX files**
Miles	Points	Duration (s)	Comments
0.5	16	2
3.8	121	10	As per 'rule' discussed. Set to 5
4.3	135	10	As per 'rule' BUT...
4.4	140	20	As per 'rule', set to 10.
12.8	220	20	As per 'rule'. (A planned walk, so no GPS.)
11.6	350	50	Set to 5.
12.3	362	55	Set to 5.
16.0	483	90	Set to 5.

Anyone else have any test data, including durations of exported video?

--
Terry, East Grinstead, UK

johnebaker wrote on 2/9/2014, 12:55 PM

Hi Terry

Here are the results of some testing I have done:

Route at constant speed
Points	Duration
35	13s 24
70	14s 4
140	15s 0
280	15s 3
560	26s 11

Duration set at 10 for all.

I did try throwing the same route at the Route wizard with 1120 and 2240 points in it, however I gave up after waiting 20 mins for the video to return.

Previous testing I did indicated that there was a non linear difference relationship between the number of points up about 500, however the routes were not all the same travel speed

The above indicate some inconsistency

John

terrypin wrote on 2/10/2014, 1:58 AM

The above indicate some inconsistency

Morning John,

You bet! Mine were clearly non-linear at best, but I wouldn't like to try curve-fitting yours.

My curiosity is piqued now so I'll try to find time for more tests. But my conclusion so far is that the Duration box is plainly no use as a tool to predetermine the length of the animation. However, in my own case (but not yours in the face of those results) so far my 'doubling rule' (for TRA time) seems to apply quite reliably up to a couple of hundred points. It's important to note that we may be comparing apples and pears. Apart from the 220 point file, all mine were actual GPS recordings of mixed average speeds, sprinkled with breaks, photo stops, lunch, etc.

I reckon the best practical approach is simply to take whatever WMV you get (after setting TRA to say 10s) and then use MEP's Speed dialog to change it to your requirement.

Was your 'Duration' column the TRA or the WMV time? Are you finding as I did that the relationship betwen those seems to be roughly WMV = TRA/2 + 4 ?

BTW, do you see any point to that peculiar slider?

--
Terry, East Grinstead, UK

johnebaker wrote on 2/10/2014, 1:42 PM

Hi ty

They are wmv times - the TRA are constant speed and do not appear to follow your rule.

John

browj2 wrote on 2/10/2014, 2:16 PM

Hi,

I was going to answer that I don't have a GPS, then I remembed that I have a sophisticated BB Z10 cell phone that can find my car. I downloaded a GPS app and went to the supermarket last night and it created a 122 point gpx file. Wow! This is great. Read the file into TRA and created a wmv file, setting at 10s, gave me 15s 5f. I tried with and without soft animation. No difference.

Next will be to see how VdG handles this.

Thanks to both of you for inspiring me to get my 3$ gps.

Regards,