[QUOTE=Del_;328644]Luke, have you tested OpenGL play back in Kdenlive? (You need to enable it in settings) If you have, please share what problems you see.
OpenGL playback has ALWAYS given choppy or laggy playback of my files, I've tested it with every card and driver I've used. They are the streams from AVCHD clips put into .flv (!) containers in avconv so I can avoid the seek issues AVCHD is known for. The best performance I ever saw in handling playback was with Nouveau on a GTS450 using XV. Running the blob the performance sucked on both XV and on Opengl, with openGL being best and lagging only on transitions-but WORSE than any open driver/card on XV.
Now using a Radeon 6750 on the open source mesa/radeon driver with all the performance optimizations (disable sync to vblank, etc). CPU is AMD "bulldozer" FX 8120 at 4.4GHZ (the 8150 was destroyed by a VRAM failure).
Power management on the video card is static by powerplayswitcher.py . All the way up or halfway up, no difference in Kdenlive, almost as good all the way down. Sometimes transitions, especially dissolves, are smooth, but other times, and most often with clock wipes, they lag enough to force choppy sound. Using ALSA on the sound card directly, Pulseaudio is removed because it creates issues with playback of AVCHD files or the files made from them in every video player.
Yet, shotcut can open that exact same .kdenlive file I save, play it back using MLT and with OpenGL enabled, butter smooth end to end even on a Phenom II X4 at 3.8GHX with a Radeon 5570 on a copy of the same OS. I would so love to see those projects merge or at least have a good old
fashioned one-night stand to mix that good DNA between the two. I now get so few kdenlive crashes, and such good crash recovery I would then see
little to ask for for what I do with video from any other editor. I've been with Kdenlive since the incredibly buggy KDE 3.5 versions back in 2007-2008, not ONCE found anything better, only things good for special tasks. Used to use Cinelerra to interpolate 20FPS video to 30, but it did a poor job, just dissolving between frames. Shotcut does a HELL of a good job of that, though "jelly roll" on 720P action shooting was also enough to junk that camera.
In answer to another question I have not run Lightworks as I cannot trust that sort of binary on my live system full of "classified" raw clips, and to prepare a system from scratch on a junk disk, then bring in everything needed to run Lightworks just for testing would be a lot of work and bandwidth(no landline at home!). Anytime you are considering airgapping from the network with two machines in one case-or a VM-you are in no position to use an editor that connects to the Internet itself. Would have to shoot special "harmless" clips just to try it-and preconvert to a format the free version could read or test only over 7 days.
I'm not saying Lightworks is BAD, not at all. I'd sure as hell rather see pro video editors run Lightworks over Linux and gamers run Steam over Linux than see them using Windows anyday.
The only reason for me to test it as of now would be curiosity, though I would definately advise developers of all FOSS editors to at least check out Youtube videos of the paid ones for comparison. If an offline version you can download without an account ever comes out, I will download it, turn off networking, install it, test it with the network disconnected, and purge before reconnecting,
About codec licenses: yes, I use the full versions of avconv/ffmpeg, no, I don't pay a penny for patent licenses when I don't recognize the authority of any government to patent software or DNA. I shoot front-line video of militant street protests, you can guess my position on "voluntary compliance" with an unjust law I oppose and which even MPEG-LA has bailed on enforcing on noncommerical users. I never sell ads or solicit donations on my videos, I would use cheaper gear first. A public library can pay for Fluendo if they fear lawsuits, I need ffmpeg/avconv. Mint (and I think Fluendo themselves too) go so far as to state that only institutional users need ever worry about codecs.