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2

Any decent encoder can hit a target bitrate (with 2pass), but still spend the bits intelligently to achieve similar quality throughout the file. x264 2pass figures out what CRF will give the desired bitrate (pass1), and then uses it (pass2). (source: Dark Shikari. cf. the links I dug up for my answer on this question about VBR streaming). You only get ...


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Use the subtitles filter to create hardsubs ("burnt-in" subtitles): ffmpeg -i input.mp4 -vf subtitles=subs.srt -target pal-dvd output.mpg -target pal-dvd will make the output have a frame rate of 25 and a frame size of 720x576. If you want NTSC output instead for a frame rate of 30000/1001 and frame size of 720x480, then use -target ntsc-dvd. For a frame ...


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So you have a client computer with a camera, and want to stream video from it to a server where it's archived and accessible? client runs: ffmpeg -i some_kind_of_input -vf mpdecimate -c:v libx264 -preset medium -crf 25 some_kind_of_output Choose an appropriate framerate to capture. mpdecimate will run constantly at that framerate. libx264 with your ...


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DASH HTML5 video streaming already works by getting the player to load video in chunks that are usually about 10 seconds long. You should be able to cook something up that gets the player to display your segment seamlessly, by giving it a DASH-like list of videos. You might need to remux your video segments into .mp4, if some web browsers choke on the flv ...


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As @LordNeckbeard wrote in the comments, moving the -t flag to after the -i flag works: ffmpeg -ss 0 -i in.mp4 -t 00:30:00 -acodec copy -vcodec copy out.mp4


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Use sound.wav as your output, instead of sound.mp3. Or if you literally mean raw PCM data with no headers, not just uncompressed, then try ffmpeg -f dshow -t 10 -i audio="virtual-audio-capturer" -f s16le -y "sound.pcm" Play it back with ffplay -channels 2 -f s16le -i sound.pcm Unless you really need headerless, I'd suggest WAV files for ease of use. ...


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ffmpeg's libx265 wrapper is very minimal, and doesn't pass on very many settings. e.g. -pass 1 requires manually setting -x265-params pass=1. Also, if x265 is anything like x264, don't use ultrafast except for lossless or for testing things. sorry for not taking the time to dig this up myself, but have a look and see if you can get your desired I frame ...


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Yes, you have the right idea. If stib's suggestion of making multiple outputs in parallel with the same ffmpeg commandline doesn't quite do the trick, then use a temp file to hold a lossless copy of the output of any slow filtering: ffmpeg -i src.mkv -vf yadif=3:1,mcdeint=2:1 -c:a copy -c:v libx264 -preset ultrafast -qp 0 deinterlaced.mkv (never use ...


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The default settings for ffmpeg are very low quality, and since you don't specify any codec or quality parameters it's just using the defaults (I don't know why the devs don't fix that because it generates a lot of questions on forums everywhere). Try adding -c:v libx264 -crf 20 -preset slow to the command. -c:v libx264 tells it to use the libx264 ...


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You can use ffprobe (which comes with ffmpeg) to give you info about your movie files from the command line. You may require some shell-fu to convert the output of ffprobe into something you can use though. I've done this in the past; basically I pipe the output of ffprobe to sed or awk to grab the bits of info I need, then use this to drive the parameters ...


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You are correct: h.264 is non-free and content producers as well as developers are obliged to pay royalties to MPEGLA for its use - but only if they are charging for their content, and the volume goes over the threshold MPEGLA sets (which is in the order of 100,000 paying subscribers or > 12 minutes in length if charging title-by-title). Thjey have also said ...


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Use it. Nothing else can provide the the same quality per bitrate as x264 (the top-class H.264 encoder) while not taking 10,000 years to encode (x265 'n VP9). Some tips: Use a recent ffmpeg build since development is so active. Static builds are available and easy. Add -movflags +faststart to your command. Once encoding is finished this option will ...


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If I am right, HTML5 supports H.264 codec with mp4 container. In this case the company which developed the browser has paid it's license. You can also use video servers for VOD playing, like Wowza Streaming Engine.


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I can't say what's going wrong or if there's a change to the ffmpeg scripts that would help, but from a practical POV I can offer some advice on how to deal with what you have. If the difference is due to drift, the fix is relatively simple. If it's due to dropped video frames or audio dropouts, it's probably not going to be fixable without a good bit of ...


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Choose your license FFmpeg is licensed under the GNU Lesser General Public License (LGPL) version 2.1 or later. Some features are covered by the GNU General Public License (GPL) version 2 or later. If those parts get used the GPL applies to all of FFmpeg. See LICENSE.md in the source to see a list of GPL parts of FFmpeg and which external libraries require ...


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In the manual it says: To use opencv use the calibration sample (under samples/cpp) from the opencv sources and extract the k1 and k2 coefficients from the resulting matrix. If you go to the opencv website there's a sample source code for a lens correction program, written in c++, here. You'll have to compile it yourself, after installing OpenCV ...



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