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46

OK then I started ffcast, did vim, quit ffcast, then converted .avi→.gif. I ran the recording commands in another terminal. Polished script for your $PATH at the end of this answer. What happened? Capturing FFcast helps the user interactively select a screen region and hands over the geometry to an external command, such as FFmpeg, for screen ...


44

See this answer. Quoted below for convenience: Calculate the bitrate you need by dividing 1 GB by the video length in seconds. So, for a video of length 16:40 (1000 seconds), use a bitrate of 1000000 bytes/sec: ffmpeg -i input.mp4 -b 1000000 output.mp4 Additional options that might be worth considering is setting the Constant Rate Factor, which ...


21

I have no .ts here but this works for .mp4. Use ffprobe (part of ffmpeg) to get the time in seconds, e.g: ffprobe -v quiet -of csv=p=0 -show_entries format=duration Inception.mp4 275.690000 so for all .mp4 files in the current dir: find . -maxdepth 1 -iname '*.mp4' -exec ffprobe -v quiet -of csv=p=0 -show_entries format=duration {} \; 149.233333 ...


20

take a look at this: http://askubuntu.com/questions/107726/how-to-create-animated-gif-images-of-a-screencast/107735#107735 ..... After the Desktop Recorder has saved the recording into an OGV video, MPlayer will be used to capture JPEG screenshots, saving them into the 'output' directory. On a terminal: mplayer -ao null <video file name> -vo ...


18

There's a dedicated tool to do this, avimerge: avimerge -o cd.avi -i cd1.avi cd2.avi


14

Newer kernels use KMS by default, so you should move away from appending vga= to your grub line as it will conflict with the native resolution of KMS. However, it depends upon the video driver you are using: the proprietary Nvidia driver doesn't support KMS[1], but you can work around it. You should be able to get full resolution in the framebuffer by ...


13

This is pretty trivially done, since .srt files are just text files that contain time stamps -- all you need to do is add the length of cd1.avi to the times of all the subtitles in cd2.srt. You can find the length of cd1.avi with ffmpeg: ffmpeg -i cd1.avi # Look for the Duration: line And then add that to cd2.srt using srttool srttool -d 12345 -i ...


13

If you are running Arch Linux I suppose you know how to install a rubygem. Take a look at https://rubygems.org/gems/airstream - a simple command-line-tool you can use to send remote and local image and video files to your apple-tv (tested with generation 3). If you need any help leave a comment on http://blog.lipautz.org/linux-and-apple-tv/.


13

Pull out the image captures (these are 100 pixels tall, and keep aspect ratio), the rate (-r) is per-second (this yields one frame every ~5 minutes), this also adds time stamp to output image. ffmpeg -i MOVIE.mp4 -r 0.0033 -vf scale=-1:120 -vcodec png capture-%002d.png Then use ImageMagick to build your gallery image: montage -title "Movie ...


12

In my case, using ffmpeg directly did the trick and provided the best result: $ ffmpeg -f gif -i infile.gif outfile.mp4


10

This command will capture your full desktop: So use this command, whenever you want to record skype-conversation ( or anything else ) ffmpeg -f x11grab -s wxga -r 25 -i :0.0 -sameq /tmp/out.mpg


10

On a Debian-based system (but presumably, other distributions will also have mediainfo in their repositories): $ sudo apt-get install mediainfo $ mediainfo foo.mp4 That will spew out a lot of information. To get, for example, the length, resolution, codec and dimensions use: $ $ mediainfo "The Blues Brothers.mp4" | grep -E 'Duration|Format ...


9

The only way to do everything you ask is to rip a disk image of the DVD and then play the image. Any other process which doesn't preserve the exact format of the disk will likely remove one or more of the features you're after because DVD is a very specific variant of the MPEG-2 standard. DVD player programs — which you still have to use to interpret ...


9

If I understood you correctly, you want one animated gif that looks like 5 animated gifs playing in parallel, right? Imagemagick can do that (and much more). Probably even in one line of code, but I'll do it in several steps. Lets assume your gifs are called anim1.gif…anim5.gif and are each 100x100 pixels. #Combine anim1.gif and anim2.gif (first row) ...


9

Something like: dd if=/dev/video0 | mplayer tv://device=/dev/stdin works for me (SOA#1) locally. So does: ssh localhost dd if=/dev/video0 | mplayer tv://device=/dev/stdin As well as mkfifo test dd if=/dev/video0 of=test & mplayer tv://device=test Hence: Try without named pipe Check bandwidth Also - how does in not work (display black screen, ...


9

There is software recordMyDesktop http://recordmydesktop.sourceforge.net/about.php which you can record any part of you screen you want. I use it to record my skype sessions. sudo apt-get install recordmydesktop to install it from main channels.


9

You can use exiftool. To install it run: sudo apt-get install libimage-exiftool-perl Then to get the metadata from mp4 file run: exiftool video_file.mp4 > medatata.txt The output saved in the file should be something like this: ExifTool Version Number : 9.60 File Name : video_file.mp4 Directory : ...


8

You need to install the gstreamer0.10-ffmpeg package. Then, to see if it works, go to http://youtube.com/html5 and see if there's a green tick next to H.264. [edit] On recent Debian versions (>= 8.0) you need gstreamer1.0-libav


8

I had the same question and I couldn't find anything so I wrote this app myself: https://procedural.github.io/GifRecorder/


8

From http://stackoverflow.com/questions/2553448: Dump all video frames $ ffmpeg -i input.mkv -an -qscale 1 %06d.jpg Dump audio $ ffmpeg -i input.mkv -vn -ac 2 audio.wav Reverse audio $ sox -V audio.wav backwards.wav reverse Cat video frames in reverse order to FFmpeg as input $ cat $(ls -t *jpg) | ffmpeg -f image2pipe -vcodec mjpeg -r 25 -i - -i ...


7

You can use Cheese (GNOME) if you just need just that, or VLC for more advanced features.


7

For sure. Here are two suggestions: Behind the scenes CLI. Use V4L2VD to create a virtual video device such as /dev/videoVirt1 and pipe through mplayer for the effects. Even some similar examples in the notes. Use a fat desktop program such as webcamstudio to create the pipes and do your skype/broadcast wonders - still with mplayer for the ascii effect ...


7

Thanks to Warren for informing me about the mediainfo command in his partial answer. I managed to construct a command that achieved the restoration of timestamps. It loops over the applicable files, and for each file, mediainfo reads the metadata, grep and sed select and format the timestamp, and touch applies it. for file in *.mp4; do touch -t ...


7

ffmpeg -i video.mp4 -vn -acodec copy audio.aac Here’s a short explanation on what every parameter does: -i option specifies the input file. -vn option is used to skip the video part. -acodec copy will copy the audio stream keeping the original codec.


6

Use fusion-icon.


6

For newer Debian & Ubuntu distros using nvidia, I had to do the following: First, edit /etc/default/grub. Change the following line: #GRUB_GFXMODE=640x480 to this: GRUB_GFXMODE=1280x800 GRUB_GFXPAYLOAD_LINUX=keep replacing 1280x800 with the desired resolution. Then: echo "echo FRAMEBUFFER=y" | sudo tee /etc/initramfs-tools/conf.d/splash sudo ...


6

According to X.org, the radeon driver is generally preferred over the radeonhd driver. This table says that you have an Evergreen chip. (That page also shows what features are implemented in the radeon driver for your chipset.)


6

I suggest you autocreate /dev symlinks using udev, using unique properties (serial number? port number?) of your USB cameras. See this (should apply to Arch as well) tutorial about udev rules. Or maybe this tutorial is clearer. You can get the list of properties for your devices using: sudo udevadm info --query=all --name=/dev/video1 then sudo udevadm ...


6

To get rid of the subtitles I believe you can add the -nosub switch, right after the .VOB file's name. Example $ mencoder Videos/Test/VIDEO_TS/VTS_01_1.VOB -nosub -nosound -ovc x264 \ -x264encopts direct=auto:pass=2:bitrate=900:frameref=5:bframes=1:\ me=umh:partitions=all:trellis=1:qp_step=4:qcomp=0.7:direct_pred=auto:keyint=300 \ -vf scale=-1:-10,harddup ...



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