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