I'm posting just to c if any one can give me some better idea than what I've been trying so far

For some reason, rendering AVCHD 1920-1080 directly with Kdenlive gives bad results as something along the way sees many end/start frames the same or frozen.

Transcoding to other formats with Kdenlive doesn't give good render video quality for me, such as DNxHD.

So I reencode the MTS files to M2ts with ffmpeg -result: no more frozen frames after render. The rendered movie is smooth where clips are joined.

However, the rendered quality (mpeg2 12Mb) is not very pleasing -has blocky appearance close-up, and it's worse than direct MTS to mpeg2 12Mb rendering. I find it strange cos the m2ts is good quality, @ 40Mb.

I've tried rendering to mp4 and h264 formats, but no better.

How can I get a better render from the m2ts? for example, rendering to DVD PAL 16:9 VOB there is no blocky effect, just poorer Q at 8Mb.
I noticed that in that render profile there are the following extra flags: bufsize=1835008 packetsize=2048 muxrate=10080000
are any of these helping the VOB output to be smoother/not blocky?

grateful for any ideas

MLT 0.8.0
ffmpeg 0.11.1
Kdenlive 0.9.2
debian wheezy

If you use Kdenlive to convert to m2t (mpeg 2 video) it changes the resolution to 1440 x 1080, so I would have thought ffmpeg did the same. Not at all sure, so check the size.

I guess its just the trade-off with mpeg2 compression gotta have Q loss

A couple of months ago I decided to check out the software bundled with my camera for converting the mts clips (Windows of course). That converted then to m2ts @ 1920 x 1080 but the quality was real ****.

In kdenlive, I can render sections of a clip to avi, pass it through stabilisation software and render it again in a project and it still looks 100% better than what the Windows software offered me.

I still have the double frames at the start and sometimes at the end but although it's annoying, it's quite easy to get by the problem.

m2ts is (I think) always 1440 by 1080 because the pixels are not square as mts/mpeg2 etc, but they are 1.33 ratio and so less pix but same aspect as what it came from

how to get round the problem?.. if I take the time to lop off areas at start/end of clips the rendering of the MTS still makes judders/stops in the new movie.

yeh, I followed the cue from the bundled software I used a year ago, convert to m2ts, then edit movies. of course there was little hope for getting anything from the software that's quality,

but with ffmpeg the m2ts = my mts quality. I think it was ubuntu where I had better luck with MTS rendering, but I'm not going back to it now!

Where you say " MTS still makes judders/stops in the new movie.", do you mean it is still the beginning or ends?

What are your AVCHD files from? Are they interlaced? ffmpeg/libav has had issues with decoding interlaced AVCHD. Do you have a native file as a sample?

In the Kdenlive Config MLT Processing threads is it still set to 1? Multithreaded decoding with ffmpeg/libav can cause issues with certain codecs.

I'd not reencode unless as a last resort and certainly not to mpeg2 or DV better to go to ffv1 or similar lossless codec. Have you tried remuxing them with ffmpeg, libav or mkvmergeGUI into a matroska container?

A sample file would be useful.

Try rendering using the webm codec. I have had a lot of good luck with this format and to be honest, I think it is probably the best format to render to.

I usually render it to about 600 if I am just transfering it youtube which works beautifully. The size is pretty small to plus you can drag this format into firefox or chromium and paly it --COOL!

Here is a sample of a simple webm to youtube I did recently: http://www.youtube.com/watch?v=rjQHTC2V6pE&list=UUUU-EIBkGv8nZ3vhHYiv8lQ&index=3&feature=plcp

Hope this helps.

thanks for the advice

1. M2TS:I've just found that encoding with h264 gives good quality from the m2ts -but it takes time on my dual core

webm also takes a LONG time from m2ts but also good Q -FFVP8 never heard of it! but handbrake is ok with it.

2. MTS: single thread attempt, got stop/pause at start of each clip after rendered, both mpeg2 and h264

but webm does it with good Q and no pauses, smaller file size as stated by hounddog, very lengthy encode
-but it makes black-outs at the end of clips!

3. REMUX to lossless- I made use of the remuxing in Kdenlive, and failed to get smooth joins still. But haven't tried remuxing outside Kdenlive with ffmpeg... will look at mkvmergeGUI this week

***
MTS sample here https://docs.google.com/open?id=0Bwr2f6nq1tMsazN5dE15eWY3Skk

I put that clip into a project and butted it up on the end of another .MTS clip. When playing, the clip change over worked fine but at the end of your clip you have 6 frames all the same. When dragging the clip in those 6 frames it played ok at either end of the other .MTS clip.

Yes, it's interlaced AVCHD, ffmpeg and libav have problems with interlaced. Maybe remuxing to mkv might help but not solve it.

**EDIT**

Just tried the sample file and see no problem with a 1080i 25fps project leaving the source as interlaced, creating an i terlaced proxy like DV or mpeg2 for smooth playback in kdenlive, butting four copies of the clip together and rendering to interlaced h264.

But did see problems trying to do a 1080p project and trying to deinterlace.

So 1080i should work fine and set media player like VLC to deinterlace, Yadif being good but more demanding on my hardware for deinterlacing HD, gave non realtime playback, using a cheaper deinterlace method like blend gave smooth playback but lower quality. So be sure that the playback problem is not media player related making it look like a bad render out of kdenlive.

Hi yellow,

This is most strange. If I load that clip into my default project settings of 1080i 25fps, the last six frames are all the same. So what's happening here?

If I open Clip Properties, it says the Frame Rate is 50 fps and scanning is Interlaced.

I thought I had better point out that my only problem has been the duplicate frames at the beginning and end of a clip. Someone mentioned in a different thread that there is a five frame problem and I believe he is right.

My workround is not trying to cut these frames off because that isn't very successful (another story), just two cuts somewhere in the clip and change timelines. A lot quicker than remuxing.

Of course, there isn't a problem at all if you're using transitions.

Just carried out my alterations to the offending clips in three Projects, re-rendered and all look great.

Happy again.

>-but it makes black-outs at the end of clips!
>but at the end of your clip you have 6 frames all the same.

This is probably because of the MTS/M2TS clips from the camera is missing some video frames at the end of the clip! The audio is sometimes longer in MTS clips.

The solution (at least for me) is to cut 4 frames from the end of every clip. Maybe some camera models leave up to 6 frames without video. It's very time consuming though to cut off the frames from each clip if you have 200 clips in a project... That's why I've suggested to add a feature to kdenlive for multi-clip-cut-off (another thread in this forums).

well, I tried once more remuxing the mts to mkv (in Kdenlive) and its a nice fast process..
then rendered some clips together
what I get is "blinks" at each clip start -though on one test not every clip had this. its a fast black-out

that gui for mkvmerge can't batch remux, its one-by-one and so a pain for hundreds of clips.