I have also big problems with scratchy sound but also with stuttering video.

Mp4 H264 clip made with Sanyo FH1 1080p 60 fps.
Default profile is 1080p 60 fps.
Same situation inside kdenlive or with the commands ffplay or mlt.
I must click several time to play with the clip viewer.

The file is playing fine, after some configuration, with mplayer (smplayer) (60%-70% CPU, software decoding).

??

It sounds likes your Sanyo FH1 MP4 file is just quite intensive to play well at this time. You can try to enable multiple decoding threads in the Advanced section of Clip Properties, but not all H.264, in particular AVCHD, can take advantage of it. Beyond that, maybe it works well enough to edit and then perhaps reduce framerate and/or res when rendering, and it should play fine in a player. If editing is too cumbersome, then try Transcode to DNxHD. Transcode is in the context menu of a clip in the Project Tree.

I don't see a transcode option to DNxHD *** 60 fps ***(?)
Moreover, I cant'see in kdenlive a batch transcoding option. One clip by one?

If I must transcode maybe it is better (for the moment) to use 1080p 30fps with my camera.

My final question is: kdenlive, with a powerful computer, is really capable of editing 1080p 60 fps?
Strangely, there is not this option in default profiles.

Most people do not need to edit 1080p60 which is why that profile does not yet exist, but you can easily define your own profiles and even share them with others for download within the application. You can also define your own Transcode profile. Just base it on the next closest one and edit the obvious framerate part. You can "batch transcode" via multiple selection or using a folder (I believe, not confirmed).

Define "capable of editing." Point me to any system that composite an unlimited number of layers in realtime. Is realtime processing with no dropped frames your definition of "capable of editing."

Thank you for the suggestions.

In this case the meaning of capable of editing is -smooth scrolling of the video and capability to play inside kdenlive, clips and timeline viewer, of 1080p 60 fps or 30 fps footage without audio or video stuttering-.

I have tried yesterday with 1080p 30 fps, editing is better, but scrolling of the video clips or timeline is sluggish and audio stuttering is also present sometime.
My computer is an intel dual core 1,8 with a Nvidia 8400, debian unstable.

Do I need a better computer?

Neither the H.264 decoder with AVCHD nor DNxHD decoder support thread-based parallelism. So, I do not think a better computer will help much at this time in that regard. I have some increased processing parallelism work-in-progress that will help down the road when there is scaling, deinterlacing, and filters involved.

The same problem on Ubuntu 10.10 32bit. When adding any mkv file into kdenlive and playing it from kdenlive there are terrible noises, and also this noise exists in rendered file from mkv. With avi files there is no such a problem. Kdenlive is installed as described on the program's site. All? kodecs are installed.
I see nobody knows how to solve this problem during a years.

As I understand it is because of some conflicts libraries, but which libraries I don't know.

yea, my advise -- don't use kdenlive 0.8, it is buggy right now, use kdenlive 0.7.8.
And don't use sunab repository -- there is no kdenlive 0.7.8 there now, only 0.8, I don't understand why.

rulet111 said : "I don't understand why."

Because 0.8 will be released tomorrow, according to kdenlive-devel mailing list.

I have only done a pre-release package of 0.8.

But if you want an archive ppa with 0.7.8 why not...


rulet111 said : "don't use kdenlive 0.8, it is buggy right now"

Can you be more accurate.

sunab.

Yes, I can. I've installed on Ubuntu 10.10 and 10.04 kdenlive 0.8 from your ppa(I've tried with and without pulseaudio) and I've got terrible noise when playing mkv from inside kdenlive(as I remember wasn't so on 0.7.8), and also rendered video from that file in kdenlive was also with this noise when playing it in external player(vlc f.e.). I also tried it with others mkv, I suppouse that because of h264 codec by which that mkv files was made. In kdenlive playing options I've tried to choose audio driver both pulseaudio and automatic with the same issue of noise. When working with usual avi files in kdenlive there is no noise. All codecs are installed, and h264 too.
It is interesting that also such a noise exists when playing the same files inside OpenShot. When playing these files with external players such as mplayer and vlc there is no proplems with a sound.
I've already deleted that systems besause I want to test kdenlive on Ubuntu 11.04 release and as I understand version 0.7.8 of kdenlive will be there, but now I don't known if the version 0.8 will work without this issue on 11.04.

Please try this command :

melt yourFile.mkv

How does it play?

Can you upload your mkv source file (or a sample) somewhere I can grab it.

Tomorrow, right now I don't have such a possibility.

Ok, here is the piece of that file http://dl.dropbox.com/u/16879592/2012-1.mkv which plays with a noise in kdenlive 0.8.
When playing it with melt command also the same noise. Here is the output of the command:

r@NGF:~$ melt 2012-1.mkv
+-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+
|1=-10| |2= -5| |3= -2| |4= -1| |5= 0| |6= 1| |7= 2| |8= 5| |9= 10|
+-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+ +-----+
+---------------------------------------------------------------------+
| H = back 1 minute, L = forward 1 minute |
| h = previous frame, l = next frame |
| g = start of clip, j = next clip, k = previous clip |
| 0 = restart, q = quit, space = play |
+---------------------------------------------------------------------+
Current Position: 258
r@NGF:~$

It's on Ubuntu 10.10 32bit.

The problem is not "mkv related". Your mkv contains 6 channels aac tracks. This is not handled by kdenlive/mlt as I see. This was discussed some time ago http://www.kdenlive.org/forum/kdenlive-and-multiple-2-audio-channels