Hi everyone,

(first post) Been using Kdenlive for two or three months now and I can't leave it alone. Excellent software. Unfortunately, I now have a problem.

Using Ubuntu 10.10 - Kdenlive 0.8.1 - MLT 0.7.2 c/o Sunab PPA.


Four of five days ago I loaded up an existing .Kdenlive containing MTS clips which were all converted to Proxy. After a little editing, rendered to MPEG-2 but it only rendered to proxy format. (no, proxy render was not checked). A few tests with other render options gave the same results.

As a test, un-checking a clips proxy setting back to MTS was not instant (as before) it sent a processor core off to 100% for some time (depending on the length of the clip). After getting all the MTS clips back, rendering worked fine. (It was worth it as the editing was an improvement)

Now though, I can't create any proxys. They just crash with "Proxy clip is unusable (duration is different from original)"

Food for thought or maybe I just need enlightening. Anyway, thanks.

normcross.

Have you tried removing the proxy clips and then re-generating them? If you right click on your clips in Kdenlive then click Properties, there is an option to delete proxy clip. I have found that fixes things when I have had issues with proxies previously. I had a similar issue when trying to make proxies where is just crashed on proxy creation.

Thanks for your reply, but sadly it made no difference.

Last night I loaded a .kdenlive project made about two weeks ago. It contained five MTS clips, 1080 50p, all with proxy. Now, proxy clips 1 and 2 showed "INVALID" in the clip monitor, clips 3 to 5 were fine. Playing from the timeline in the Project Monitor all proxy clips play fine.

If you un-check "Proxy" on clip 3,4, or 5 and re-check it, "generating proxy" shows followed shortly by "Proxy crashed".

I still can't create any Proxys without the "Proxy clip is unusable...." statement then "Proxy crashed"

Looking to the left at the Commits section it says "Display error message if proxy duration is incorrect" and that's dated 28th April. That's roughly the date mine stopped working. Naaa, just got to be a coincidence.

Sorry just an update to the above, the Invalid clips do not play. Also another point, if I render a section of the working clips it is still rendered to proxy format only whatever format I use.

Feeling very hopeful, I have just installed Sunab's latest build of Kdenlive 0.8.1 r5574 and MLT 7.3 but alas my Proxys still do not work at all. The same "duration different" statement.

Now, this gets me thinking that the problem is possibly at my end.

Is there anyone who could give me some idea of where to look. Since the Proxys stopped working I'm almost dead in the water, still got three fingers up though.

Any help would be much appreciated.

Sorry I took a long time to post in this thread. Here is the explanation for the "proxy crashed" issue:

Just before the Kdenlive 0.8 release, I realized there could be a major issue with proxy clips. Sometimes, when transcoding a clip to create a proxy, the proxy clip does not have the same length as original clip (it's just a few frames of difference).

In Kdenlive, this can lead to some very serious issues, since we replace original clips with proxies. Having a different duration means we could end up with a corrupted timeline and broken project. That's why as a safety workaround, I decided to discard a proxy clip if its duration is not correct.

So now what?

In my tests, the duration problem does not always appear. It depends on the format of your source clip and the proxy encoding parameters. As a workaround, you could try to change the proxy encoding params (in Project->project settings):

replace "-f mpegts" with "-f avi" in the parameters and put "avi" as extension instead of "ts"

That might fix the issue. I still have to do more testing with MLT to see if we can find a better way to solve the duration issue.

regards.

j-b-m

Many thanks for finding the time to explain. I can see the dilemma but happily await the outcome. Unfortunately, the avi suggestion didn't work.

No more whining now.

Just a point. This means then, that when Proxy popped into the menu and I used it constantly, all my proxies where incorrect but I didn't have any problems at all. I know, the threat was lurking in the background.

Thanks.

The problem with proxy duration only shows if you use the last frames of the video clip in timeline, which is not often the case. Using just a part of the clip will not cause any problem, that's probably why several people worked successfully with proxies.

Will post here whenever I find a better solution.

regards

I just checked and it looks like MLT can now handle this issue properly. I committed a fix to Kdenlive svn (rev. 5584). For those who want to try, you will also need the latest MLT (from git).

j-b-m

A joy to read. Many thanks for your time on this. Installed just now, selected a clip and the proxy worked fine. Selected the other five clips and watched five cores power to 100% and in a few seconds, all working.

Thanks. My thanks also to Sunab for having it built so quickly.

Thanks for this! The proxy feature makes it actually possible to use Kdenlive to edit HD video on my **** netbook while on vacation (though I wouldn't recommend it to anyone).

One note: a user will also get the "proxy crashed" error message if certain libraries are not installed that are called by the ffmpeg transcode; on my Linux Mint 10 system, this meant 'libmp3lame'. As that library is not installed, the transcoding of the proxy failed with the "proxy crashed" message, even after upgrading to the latest Kdenlive / mlt versions as of May 24 2011.

Two solutions/workarounds:
1. Install the package "libavcodec-extra-52" (sudo apt-get install libavcodec-extra-52), which includes the necessary libraries.
OR
2. Under Project, Project Settings, FFmpeg video transcoding parameters, replace the audio switches "libmp3lame -ac 2 -ab 92k -ar 48000" with the word "copy", which apparently will just retain the original audio track from the source file.

I did #@ before I found solution #1, and it seemed to work just fine, though I'm sure there is a reason why it wasn't done that way in the first place. I haven't actually rendered anything yet (I _am_ on vacation), so guess #2 might cause some kind of problems at that point.

(for #2, make the same change to "Settings, Configure Kdenlive, Project Defaults, FFmpeg video transcoding parameters to make this apply to new projects as well)

-- BV

I've got FULL HD AVCHD Files, most of them could be changed to proxy files, and working, but some not.
I tried various things, and every advise from this Thread with no luck.

Mean while I changed from 10.04 to Ubuntu 11, reinstalled the lib av extras 52 from the multiverse, checked my libmp3lame, than I gave the Voodoo Lady the pearly-white bra and the bone. I also gave her the spit and the toupee ...
the proxy crashed, but for now I have a voodoo doll ... so please tell me how to fix this Problem or you might regret!

Interesting - after transcode to DNxHD the proxy still crashes with a DNxHD file. So I'm sure it has something to do with AC3 Sound.

This thread has the highest ranking in Google, thats why I'm using an old Thread, and there are still useful informations.

@yt: which MLT / Kdenlive versions?

Good Morning,

it is
0.8.0-0ubuntu0~sunab~natty1 Kdenlive and
0.7.2-0ubuntu0~sunab~natty2 Melt

I tried to eliminate the Sound Problem, by rendering the clip without sound as DNxHd,
reimport and build a proxy ... no luck.

coincidently, as I split the clip,
one part could build a proxy ... the other one not.
But I couldn't find any explanation why.

I have found some small sample clip from my artwork that is such an annoying *beep*

You can download it here:
http://yours-truly.de/files/Kdenlive/scanCloud.mp4 (about 13mb)
I can not generate a proxy of it. But, when I transcode it to DNxHD, the proxy clip could be generated with this values:
-f avi -acodec libmp3lame -ac 2 -ab 92k -ar 48000 -vcodec mpeg2video -g 1 -deinterlace -s 854x480 -b 12000k
[*.avi]

I tried the same procedure at this clip:
http://yours-truly.de/files/Kdenlive/22.mov
But here the proxy crashes.

Again:
scanCloud.mp4 - generate Proxy = crash
scanCloud.mp4 - Transcode DNxHD - scanCloud.mov - generate Proxy = no crash

22.mp4 - generate Proxy = crash
22.mp4 - Transcode DNxHD - 22.mov - generate Proxy = crash


Nice Greetings,
yt