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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
Grab X11 input and create an MPEG at 25 fps with the resolution 800x600
rips the audio and video stream of a movie. The two streams are stored separately.
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
Takes an mpeg video and coverts it to a youtube compatible flv file.
The -r 25 sets the frame rate for PAL, for NTSC use 29.97
-vn removes tha video content, the copy option tells ffmpeg to use the same codec for generating the output
I used an flv in my example, but it'll work on any file ffmpeg supports. It says it wants an output file, but it tells what you want to know without one.
This converts all m4a files in a dir to flv. You can just swap the m4a bit to anything else ffmpeg supports though, and it'll work.
This is handy for making screenshots of all your videos for referring to in your flv player.
Download YouTube videos as .flv and convert them to .3gp for your mobile phone.
-vcodec, you choose what video codec the new file should be encoded with. Run ffmpeg -formats E to list all available video and audio encoders and file formats.
copy, you choose the video encoder that just copies the file.
-acodec, you choose what audio codec the new file should be encoded with.
copy, you choose the audio encoder that just copies the file.
-i originalfile, you provide the filename of the original file to ffmpeg
-ss 00:01:30, you choose the starting time on the original file in this case 1 min and 30 seconds into the film
-t 0:0:20, you choose the length of the new film
newfile, you choose the name of the file created.
Here is more information of how to use ffmpeg: