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Create a transition between two videos
We take the first 50 frames of a.mp4 for track a, and 24 blank frames followed by b.mp4 for track b. We then create a transition from track a to track b starting from frame 25 and ending at frame 49. The output is stored in out.mp4 To view the results without saving remove "-consumer avformat:out.mp4" from the end. Documentation of the mlt framework and the melt command can be found here: http://www.mltframework.org/bin/view/MLT/Documentation

Convert encoding from cp1252 (MS Windows) to UTF-8 on source code files

combining streams
2>&1 permit to combinate stdout and stderr. grep will catch stderr and stdout instead of stdout only.

Video Google download
Download google video with wget. Or, if you wish, pass video URL to ie mplayer to view as stream. 1. VURL: replace with url. I.e. http://video.google.com/videoplay?docid=12312312312312313# 2. OUPUT_FILE : optionally change to a more suited name. This is the downloaded file. I.e. foo.flv # Improvements greatly appreciated. (close to my first linux command after ls -A :) ) Breakedown pipe by pipe: 1. wget: html from google, pass to stdout 2. grep: get the video url until thumbnailUrl (not needed) 3. grep: Strip off everything before http:// 4. sed: urldecode 5. echo: hex escapes 6. sed: stipr of tailing before thumbnailUrl 7. wget: download. Here one could use i.e. mplayer or other...

Read aloud a text file in Mac OS X

Do the last command, but say 'y' to everything
I doubt this works with other than bash, but then again, I havent tried. The 'yes' utility is very simple, it outputs a hell of a lot of 'y's to standard input. The '!!' command means 'the last command'. So this one-lines inputs a lot of y's into the last command, aggressively agreeing to everything. For instance, when doing apt-get.

List all accessed configuration files while executing a program in linux terminal (improved version)
Last listed files presumably have higher precedency then files listed first, i.e. configuration files in the personal .config directory will be listed last and their config parameters will be more authoritative then default config parameters defined in /etc directory which are usually listed above them. If you replace ".conf" with ".ini" in the command, initial files will be listed instead of config files. If you do not like to list multiple access to the same config file, pipe to "uniq" or "uniq -c" to prefix lines by the number of occurrences

Update grub menu.lst
Remove all commented lines Remove all blank lines Show the menu Up the delay so you have enough time to select a kernel Remove the quiet so you can watch the entire boot Add a rootdelay for san attached storage booting

Rename files in batch

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }


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