Record from a webcam, audio using ALSA encoded as MP3, video as MPEG-4.
Yet another x11grab using ffmpeg. I also added mic input to the capturing video stream using alsa. Yet I need to find out how to capture audio which is currently playing. Show Sample Output
To rip DVD movie to ogg format using ffmpeg, follow these steps. 1) find the vob files on the mounted video DVD in VIDEO_TS that stores the movie itself. There would be a few other VOB files that stores splash screen or special features, the vob files for the movie itself can be identified by its superior size. You can verify these vob files by playing them directly with a player (e.g. mplayer) 2) concatenate all such vob files, pipe to ffmpeg 3) calculate the video size and crop size. The ogg video size must be multiple of 16 on both width and height, this is inherit limitation of theora codec. In my case I took 512x384. The -vcodec parameter is necessary because ffmpeg doesn't support theora by itself. -acodec is necessary otherwise ffmpeg uses flac by default.
Takes all the .3gp files in the directory, rotates them by 90 degrees, and saves them in the lossless ffv1 encoding. If this rotates in the wrong direction, you may want transponse=1 Re-encoding to ffv1 may result in a significant increase in file size, as it is a lossless format. Other applications may not recognize ffv1 if they don't use ffmpeg code. "huffyuv" might be another option for lossless saving of your transformations. The audio may be re-encoded as well, if the encoding used by your 3gp file doesn't work in a avi container.
This assumes that there is a 10.2 sec delay between the video and the audio (delayed). To extract the original video into a audio and video composites look at the command on extracting audio and video from a movie
This is an extract from a larger script which makes up slideshow videos from images. $seconds is the number of seconds the video will last, and $num is a loop counter which numbers the videos for concat into a longer video later, so they will be in order. The dev/null bit on the end cuts ffmpeg's verbosity.
Record audio to an MP3 file via ALSA. Adjust -i argument according to arecord -l output.
Rebuild flv files that are broken (can't seek). This method probably works for other video/audio formats that can become broken in the same way.
Creates a 5 minute flv file, with the given sequence of images and audio with 0.5 fps. The images were created using the following command: for x in `seq 0 300`; do cp ../head.PNG head-`printf '%03d' $x`.png; done You can also inject metadata to seek easier using yamdi as follows: yamdi -i muxed.flv -o video.flv Show Sample Output
A batch file version of the same command would be: for f in *.m4a; do ffmpeg -i "$f" -acodec libmp3lame -ab 256k "${f%.m4a}.mp3"; done
Usage: videospeed video_filename speedchange newfilename videospeed foo.mp4 0.5 foo_slow.mp4 Range of 0.5 (50%) - 2.0 (200%) is valid.
Streaming HTML5 compatible video (Ogg Theora video with Vorbis sound) to an Icecast server using dvgrab, ffmpeg2theora and oggfwd. In this example I'm merging stereo sound to mono (-c 1), saving the original dv for later higher quality on-demand video (tee dvstream.dv), saving the theora stream for immediate on-demand video, and publishing the stream in Xiph's stream directory (-p and the name and description). The URL of the video will be (depending on your server) http://my.icecastserver.com/stream.ogv which will play in newer Firefox, Chrome and Opera web browsers. Cortado (a Java player) can easily be used for IE. Note also that I'm using port 80, which is not the default port for Icecast, this is to avoid restrictive firewalls. Also note that ffmpeg2theora 0.25 and will heed the bitrates much better than former versions because of using libtheora 1.1 or newer.
The option -an disables audio recording, -f forces the use of video4linux for the input, -s sets the video to the size 320x240, -b sets the recording bitrate, -r sets the frame rate to 15fps, -i gives the input device, -vcodec sets the output format. Press Q to stop recording or you can specify the recording time with the -t option like -t 00:1:30
This uses mpg123 to convert the files to wav before burning, but you can use mplayer or mencoder or ffmpeg or lame with the --decode option, or whatever you like.
There are some pretty good live performances on late night TV. With Mythtv I record David Letterman, Jimmy Fallon, and Conan nightly all in HD from over the air broadcasts. If I find a live performance I like I copy it to my Rockboxed iPod using this command. The Rockbox firmware knows how to downmix 5.1 audio. The command above extracts the audio from the video starting at 58 minutes and 15 seconds. It ends at the end of the file since this was the last performance of the recording. The command creates an ac3 file. I copy the ac3 file to my Rockbox iPod and rock on.
same as above but dumps the stream to a file.
gorecord foo.mp4
I've tried all of the screen recorders available for Linux and this is easily the best. xvidcap segfaults; VNC is too much hassle. There are alternatives of this command already here that I am just too lazy to reply to. Messing with the frames per second option, -r, 25 seems to be the best. Any lower and the video will look like a flipbook, if it records at all - -r 10 won't - any faster is the same, oddly enough.
Edit: CLF doesn't like my long command to add audio, so here it is in the description.
goaddaudio()
{
if [ $# != 3 ]; then
echo 'goaddaudio < audio > < src video > < dst video >'
return
fi
f=goaddaudio$RANDOM
ffmpeg -i "$2" &> $f
d=$( grep Duration $f | awk '{print $2}' | tr -d ',' ) &&
rm $f &&
ffmpeg -i "$1" -i "$2" -r 25 -ab 192k -ar 44100 -sameq -t $d "$3"
}
ffmpeg -i = input file name -s = set frame size, qcif=176x144 -vcodec = force video codec -r = frame-rate [default = 25] -b = bit-rate [200 kb/s] -acodec = force audio codec -ab = audio bitrate in bits/s [64k] -ac = no. of audio channels [1] -ar = audio sampling frequency [44100 Hz] optional: -sameq = use same video quality as source (implies VBR) -f = force format -y = overwrite output files
This is an alternative to #9131. ffmpeg didn't work on my .au files, though it did on the .wav ones. Also useful if you don't have ffmpeg but do have sox. Handily, sox already reports in seconds (decimal). Show Sample Output
-map 0.0:0 map the video of video.mp4 to the video of mix.mp4 -map 1.0:1 map the audio of audio.mp3 to the audio of mix.mp4 make sure that video.mp4 and audio.mp3 have the same duration
This removes the video and subsequent file size and directly copies the audio. Show Sample Output
I had to compress it a bit to meet the 255 limit. See sample for full command (274) usage: ffgif foo.ext Supports 3 arguments (optional) ffgif filename seek_time time_duration scale ffgif foo 10 5 320 will seek 10 seconds in, convert for 5 seconds at a 320 scale. Default will convert whole video to gif at 320 scale. Inspiration - http://superuser.com/questions/556029/how-do-i-convert-a-video-to-gif-using-ffmpeg-with-reasonable-quality/556031#556031 Show Sample Output
Uses parallel processing Reiteration of my earlier command https://www.commandlinefu.com/commands/view/15246/convert-entire-music-library Usage lc Old_Directory New_DIrectory Old_Format New_Format lc ~/Music ~/Music_ogg mp3 ogg Show Sample Output
Open a window that displays camera capture. Framerate, width and height may be changed to match your needs.
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