Add this argument somewhere in the command, set off by spaces-for example, right before specifying the output file. Set the bitrate of the output file with the -b:v argument. To extract only the audio portion of a video, use the -vn parameter to indicate no video output: Using a small GOP value in step one makes this quick jump possible:įfmpeg -ss target-1 -i temp.MXF -ss 1 -q 2 -t duration_of_chunk out.mpg Here's one strategy for extracting video from MXF files that has worked:ġ) convert to a format that has a small GOP (group of pictures) value -g 1Īnd keep a high video bit rate ( -b:v) to keep detail in the video:įfmpeg -i my.MXF -g 1 -b:v 35000k temp.MXFĢ) seek in the temp.MXF file to just before your target start time for the extracted video - the first seek (ss) in this command jumps to 1 second before the target very quickly and the second seek steps over frames until it gets to exactly your target time. This command, for example, would extract a 1.5-second clip starting at 5.3 seconds into 'longfile.avi' and save it to 'shortfile.avi':įfmpeg -ss 00:00:05.30 longfile.avi -t 1.5 shortfile.avi
To extract video from a certain time, use the -ss and -t flags to specify start time and duration, respectively:įfmpeg -ss HH:MM:SS INFILE -t DURATION OUTFILE 4 Changing the video resolution (scaling).
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