On Tue, Aug 17, 2010 at 9:06 AM, Paul Hartman <paul.hartman+gen...@gmail.com<paul.hartman%2bgen...@gmail.com> > wrote:
> On Tue, Aug 17, 2010 at 9:08 AM, Kevin O'Gorman <kogor...@gmail.com> > wrote: > > On Mon, Aug 16, 2010 at 1:21 PM, Paul Hartman > > <paul.hartman+gen...@gmail.com <paul.hartman%2bgen...@gmail.com>> wrote: > >> > >> On Sun, Aug 15, 2010 at 10:02 PM, Kevin O'Gorman <kogor...@gmail.com> > >> wrote: > >> > My underling thing, if anyone can make other suggestions, is that my > >> > camera > >> > broke, and I had to get > >> > one in a hurry, and didn't really know what to look for. I wound up > >> > with a > >> > fairly good Sanyo 1080p camera > >> > and video recorder that's super light, and not too expensive. The > >> > problem > >> > is that its videos are MP4s, > >> > which are definitely not ready to put on a web site, and I know > nothing > >> > about transcoding. My previous > >> > camera took acceptable .avi videos, which had worked with most folks > >> > browsers. The MP4s are huge > >> > and in a weakly supported format. > >> > >> You might want to check out kdenlive which is a full-featured video > >> editor (using mlt as backend) but includes a simple transcoding > >> function and several presets for many different formats (with the > >> added bonus that you'll be able to edit your raw video should you so > >> desire). > > > > Thanks, I emerged kdenlive. I can not open my MP4 files, but I can add > them > > as clips. Okay. > > > > The clips do not play in any reasonable form. I get moments of sound, > and a > > few pixels > > changing on screen; nothing coherent. I'd been told that H264 needs a > lot > > of CPU and I > > guess an old 4-core 32-bit XEON (effectively 800 MHz each) on 2 GB ECC > DDR1 > > is not enough. Okay. > > I don't think you'll be able to play back HD video in real-time on > that hardware. Even on, for example, Core 2 at 3GHz playing HD video > used something like 90% CPU (without a hardware mpeg4 decoder). > > > The killer though, is that I cannot figure out how to export that clip in > > some other form. > > And of course, I'm clueless about what form would be optimum. Asking for > > help takes > > me to a forum that has a thread on the topic, but no useful answer. > > You need to add it as a clip, then drag that clip to the timeline in > the lower half of the window. It may take it a while to process once > you've dropped it here (I believe it thumbnails/indexes the video). > It's sort of like a multi-track audio editor, you can overlay effects, > drag the ends of the video clips to change the start/end point, etc. > The more effects you add the slower the encoding will be. For example > I used it on a 5-minute video from my wedding to fade-in and fade-out, > print a title at the beginning, and normalize the audio. I encoded it > to a 720p mp4 which I could then upload to YouTube and let YouTube > re-encode it to lower resolutions for people who can't do HD. > > Once you've got your clip on the timeline, to save as another format > click the "Render" button. In the Render window, you can choose the > output format. It will give you many options such as MPEG-2, XviD, > Flash, RealVideo, Theora etc. You can also adjust the output video > dimensions and bitrate. Hopefully you can find something that will > work for your audience. If you have other video files that worked well > for you in the past, you might check out what their specs are and try > to mimic it. > > It will probably take ages to process, depending on how long your > video is. I have a Core i7 920, overclocked, and encoding a 1440x1080 > interlaced video to another format still takes more time than the > length of the video clip (usually 1.5 to 2 times with no effects > added). Since you're dealing with even higher-resolution video and > slower hardware I imagine you're probably looking at overnight, or > days, depending on how much video you're dealing with. > > One "trick" to speed things up is to first transcode your video to an > uncompressed format, and then do all of your editing operations on > that uncompressed file. This requires massive amounts of disk space > and fast disks, though (I think a 5 minute clip was about 70 > gigabytes). > > > Is there a kdelive tutorial anywhere? One basic walkthrough and I'd > > probably be able > > to figure out the rest of what I want. > > There are some video tutorials here: > http://www.kdenlive.org/tutorial > > And the user manual has a quick-start section, I believe: > http://www.kdenlive.org/user-manual > > If you don't really need or want HD video, you might also consider > going "old school" and getting a video capture card (which encodes to > something more CPU-friendly like mpeg2). Then you could play the video > on the camcorder and record it onto the computer and let the capture > card do the heavy lifting. > > If kdenlive is a dead end, other alternatives might be: > Install handbrake binaries into your user directory, forgetting about > portage entirely for the moment. > Use ffmpeg if you can figure out the commandline options (I never can) > Other video-converter packages include tovid, though support of HD > video might not be there. > > Good luck! > > Great! Thanks for all that useful information. I think I'll be good from here. I was going to upgrade that 2002 Xeon system anyway (but maybe no right away), but my results now make sense to me, and your information very clear. ++ kevin -- Kevin O'Gorman, PhD
