Two 100€ bouties (dropped)

Edit : as I don't know how to split the bounties, I prefer to drop them.
Email me within a week if you would like to receive the bounties.

In the name of my website (80.000 unique visitors every month),
we are offering two bounties for important features which lack or are partially available in Kdenlive:

Visit this page for more information: ... hp?t=31588

This is not a large sum of money ... but it really shows these are important features.
Bringing these features to Kdenlive could be usefull to inform thousands of people.

The effects are needed in a movie called Les super-héros de l'immobilier, which is shot in hidden cam in real-estate agencies.
Your contribution is more than welcome to Free software. We need your help!

Kind regards,

I recieved a message from Zach:

Check out this file in the mlt source:
That file includes examples of how to use my motion estimation module. Here are the relevant lines:
To automatically track an object in the frame, try this:
> inigo -filter autotrack_rectangle:X,Y:WxH debug=1
(Where X,Y is the origin of the rectangle indexed from upper left and WxH is the dimensions of the rectangle.)

To obscure that same object in the frame, try this:
> inigo -filter autotrack_rectangle:X,Y:WxH obscure=1

In other words, the face motion tracker should be very easy to do if you already have an interface to place the oval.

Dear Zach,

In fact, to be more precise, I do not really care whether it is a rectangle or an oval.
All I need is a better interface than the existing Kdenlive pixelisation effect.

I am glad to notice that MLT supports the needed features.
Now we need a good and workable UI in Kdenlive.

Kind regards,

To add more details,

The autotrack_rectangle uses motion_est and obscure filters to track the region as it changes through frames and obscure it.

My autotrack_rectangle filter is called with initial parameters very similar to the obscure filter you already have in kdenlive. The main difference is that there is only a start geometry and not an end geometry. Another difference is that autotrack_rectangle filter doesn't pass the "averaging" value onto the obscure filter but I can fix that for you.

There are some pitfalls though:

Previewing the filter is not going to work well yet. The autotrack filter expects that the frames will be stepped through sequentially. This will work fine during render but not during preview unless it's played through sequentially. This can be (mostly) solved by caching the geometry. To completely solve it there would also need to be a "pre-render" to fully cache the geometry before jumping around in the preview. The tracking code is extremely fast so this shouldn't be a performance problem.

Finally, the autotrack works very well but there will always be corner cases where the geometry drifts too far off the center of the target.

Here is a sample video from a few years ago:

I don't have kdenlive development experience and no c++ skills. I'd be happy to do the mlt work if someone else did the kdenlive work and wanted to split the bounty.


I dumped this info into the MLT Wiki: ... kRectangle

Eventually, I will tie it in as I improve the docs. Consider when you start to writeup a lengthy description or howto, to add it to a wiki and then link to it.


Just a quick note to tell you that I got the autotrack feature working in kdenlive, works quite well. It requires some changes in the MLT autotrack_filter, will try to send the patch soon.


Good, tell me how to split the bounty and pay the first 100€.

I am droping the sound level bounty as noone is really picking up this issue.

Also, I would like to pay the face tracking bounty.
Without answer within a week telling me who to pay, I am dropping this bounty too

If your bounty has been filled and no one steps forward, consider paying out to the developers who made the KDEnlive program in the first place.

Hey it's not my money, so I second the motion =)