Echo eduardo.

It would be nice to have some way to batch-render a whole directory full of .mts files in advance of commencing editing . . . ? At this point it seems the only way to do this is to load each file and set up a render one at a time.

On the other hand, direct AVCHD editing at this point isn't too bad on my HF100 files. There are a few glitches:

• About 1 in 20 clips doesn't seem to always render - I get grey video over correct audio for the clip duration.


• Trimming the clip by dragging the left or right in-out points can result in screwed up playback for that clip.


• Playback in the timeline monitor works quite well if you start playback from the clip beginning. If you play from the middle of the clip usually nothing plays until the cursor reaches the following clip.

Despite this, it's surprisingly usable and I've done some nice projects already. So I'm wondering if maybe AVCHD editing is close to being more or less solved, and maybe in the next release these difficulties may clear up.

ArtInvent, you can use ffmpeg on the command line to do batch conversion. You don't need to go through kdenlive for that. I'll post a script later tonight.

I think I had the same glitch you had, in which some clips render as gray. I have a project in which the last clip fades to black. In the rendered output, the last clip is turning out as a gray screen, which then fades to black. I thought it was a fade bug, but it's likely that it's the same AVCHD bug that you have.

I have your other issues too (trimming and  playback from the middle), but they are minor since they don't affect the output.

And I have a fourth issue: sometimes, between clips, there is one black frame. It's a very quick black flash. Have you had it? I've set up my project by adding several clips to the timeline at once, in one drag operation. So in theory they should be touching perfectly, with no space between them. This only happens on the rendered output.

I think I've noticed the black frame or some kind of glitch between clips in rendered. It's quite minor.

I have one clip that I really needed where the first few seconds the image rendered in slow playback and the sound got out of sync. I did pre-render that to very hi-bit mpeg-4 intermediate - but then it cleared up and seems to be okay now. About the only thing I changed since then is I installed 3-4 extra libs that are marked 'unstripped' that hadn't been installed before. Have no idea if all of these are necessary but here's all I have:

libpostproc-unstripped-51,libavdevice-unstripped-52,libswscale-unstripped-0,libavfilter-unstripped-0,libavutil-unstripped-49,libavcodec-unstripped-52,libavformat-unstripped-52

Also, I still don't have frei0r installed, as I really don't have much need for effects at this time.

Kdenlive was also crashing before and now seems much more stable.

The other problem I have is that 1080 x264 renders don't seem to want to play at all and hang mplayer pretty badly.

I'm in the process of setting the www.avenard.org repos for Jaunty, which have updated mencoder, mplayer, x264, and most importantly the 180.51 nvidia driver rather than what I'm using now (180.44). Hoping this might help matters some. Must reboot now.

Yes, the idea is to convert your AVCHD to DNxHD for editing. And, of course you can script it. You could convert my avformat properties in that render profile to ffmpeg options and use ffmpeg. Or, you can use e.g. 'inigo -profile atsc_1080p_25 some.mts -consumer avformat:some.mov <my avformat properties from the profile>'. If you add threads=N (-threads N for ffmpeg), you can do multi-threaded encoding.

You do not need to convert the clip in its entirety, but if you trim the beginning (use an in point), then you run the risk of a non-clean transcode. DNxHD is a bit faster, but I also just submitted a small change to MLT to make seeking/scrubbing even faster.

To Artinvent: Here is my scripts to batch convert videos. Are you on Linux?

until [ -z "$1" ]

do

    ffmpeg -y -threads 2 -i $1 -acodec libfaac -ab 256k \

        -vcodec mpeg4 -vb 36M -s 1920x1080 -intra -flags +ildct+ilme $1.mov

    shift

done

I saved it as "ffmpeg-1080i" and put it in my /usr/local/bin. The usage is: ffmpeg-1080i *.MTS

It converts all .MTS files in the current directory. Just leave it running overnight!

Eduardo

Edit: Of course you're on Linux, if you're using kdenlive! :) I asked that because ffmpeg itself is cross-platform, and I also have it in my Windows and Mac computers. Hopefully you can put the script above in a text file, save it and use it, there are a few different ways to do that, let me know if you have problems.

Why?

Thanks eduardo. I will be trying this. And yes, I'm on Linux, Ubuntu 9.04 64.

One thing - this is using the regular mpeg4 codec, right? Not the near-lossless codec we were talking about? Or am I missing some trickery?

Right now the 'overnight down time' on my computer is being taken up rendering some Blender files in HD. It takes about four hours to render 10 seconds of finished video at 1080p  - !

What is wrong with this picture? It would surely be nice if more video software would start taking advantage of the GPU which just sits there staring at it's navel and twiddling it's thumbs while all this video/transcoding/3D rendering is going on.

hi

i have the same problem, buy an avchd cam because it's not easy to find affordable no-avchd cam and i need to convert to mp4 (or other) because i don't have a Cray one laptop ...

So there is a lot option for ffmpeg to convert avchd to mp4 ... if you can rapidly how to do that without big loss in quality ...

thanks

ArtInvent:

No, that script uses regular mpeg4. I was looking into DNXHD and the bitrate is WAY too big :( It only supports a few fixed high bit rates (table here: http://www.avid.com/resources/whitepapers/dnxhd.pdf). I know I said I have a lot of disk space, but I don't have any perceptible loss when converting to MPEG4 720p (q=1.6), and I already have good editing performance on single core with it. I'm afraid I may run into hard disk transfer bottlenecks rather than CPU bottlenecks, with such high bit rates. I may try it when I have to do a really professional project. For now it's just home recordings.

Anyway, if you want to try it, change MPEG4 to DNxHD on the script above, and be sure to use one of the valid bitrates from the pdf above or you'll get an error. For example, for 1080/60i use "-vb 145M".

nyme:

The script I posted above converts avchd to mp4 if you change the file extension from .mov to .mp4. There's no big loss in quality.

Eduardo