How to convert a video file in format as flv to mp4 with ffmpeg? You may use method from here: https://www.systutorials.com/3540/converting-video-files-for-ipod-iphone-ipad/ ffmpeg -i input.flv output.mp4 Or by specifying more details about how to handling the codecs: ffmpeg -i input.flv -vcodec copy -acodec copy output.mp4 You may also add more options as you like. For more,
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Author: Eric Ma
Eric is a systems guy. Eric is interested in building high-performance and scalable distributed systems and related technologies. The views or opinions expressed here are solely Eric's own and do not necessarily represent those of any third parties.How to install ffmpeg on Linux Mint 17 Qiana?
Posted onHow to install ffmpeg on Linux Mint 17 Qiana? To install FFmpeg on Ubuntu 14.04 Trusty Tahr, Linux Mint 17 Qiana and etc: $ sudo add-apt-repository ppa:jon-severinsson/ffmpeg $ sudo apt-get update $ sudo apt-get install ffmpeg Does anyone know why this was taken out of the main repositories? Linux Mint 17 is based on Ubuntu
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How to install WordPress Buddy Press template?
Posted onHow to install WordPress Buddy Press template? Themes for BuddyPress are available at:http://wordpress.org/extend/themes/tags/buddypress Make sure that the theme tagged as “buddypress” is compatible with the BP/WP version activated in your server. As of BuddyPress 1.7, BuddyPress works with most any WordPress out of the box. BuddyPress 1.7 includes base template files that should fit into
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How to redirect HTTP to HTTPS in Apache with mod_rewrite?
Posted onI’d like to force using of https on one of my site. How to redirect HTTP to HTTPS in Apache with mod_rewrite? You can put these lines to the .htaccess file in the directory from which you would like to redirect HTTPS to HTTP: RewriteEngine On RewriteCond %{HTTPS} off RewriteRule (.*) https://%{HTTP_HOST}%{REQUEST_URI}
How to run programs in different languages from Windows’ language
Posted onHow to run programs in different languages from Windows’ language? For example, some non-unicode programs in Chinese on English version of Windows will display some garbage characters. You can use the AppLocale util provided by Microsoft to run legacy applications without changing language of non-Unicode applications (system locale): https://en.wikipedia.org/wiki/AppLocale You may check this link for
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How to install no-ip update client on Linux Mint?
Posted onHow to install no-ip.com update client noip2 on Linux Mint 17? First, install the noip2 client: sudo su – cd /usr/local/src wget http://www.no-ip.com/client/linux/noip-duc-linux.tar.gz tar xzf noip-duc-linux.tar.gz cd no-ip-2.1.9-1 make make install Then, generate the configuration file noip2 -C Last, make noip2 daemon run at reboot crontab -e Add this line to crontab: @reboot /usr/local/bin/noip2 I’ve
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How to clone a snapshot of a remote repository at a specific branch?
Posted onI know that one can make a zip of the current branch by: git archive -o archive.zip HEAD However, at situations, one may want to clone a copy/snapshot of remote repository at a specific branch because: 1) The repository is large with long history and cloning the whole history takes too much time. 2) What
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How to set up HP printer drivers on Linux Mint?
Posted onHow to set up the driver for an HP printer on Linux Mint or Ubuntu? First install the packages: sudo aptitude install hplip hplip-gui Then run sudo hp-setup and follow the GUI instructions to set up the printer.
How to set the number of mappers and reducers of Hadoop in command line?
Posted onHow to set the number of mappers and reducers of Hadoop in command line? Number of mappers and reducers can be set like (5 mappers, 2 reducers): -D mapred.map.tasks=5 -D mapred.reduce.tasks=2 in the command line. In the code, one can configure JobConf variables. job.setNumMapTasks(5); // 5 mappers job.setNumReduceTasks(2); // 2 reducers Note that on Hadoop
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How to view a file at a specific commit in git?
Posted onHow to view a file at a specific commit/revision in git? You can use git show to view a file’s content at a specific commit in git: https://www.systutorials.com/docs/linux/man/1-git-show/ $ git show REVISION:/path/to/file You can also save a copy by $ git show REVISION:/path/to/file >file.copy
How to change hostname on Linux Mint?
Posted onHow to change the hostname on Linux Mint? The hostname (e.g. mypc or mypc.example.com) can be changed by putting the hostname in one line in the file /etc/hostname on Linux Mint.
How to jailbreak iOS 7.1.2?
Posted onHow to jailbreak iOS 7.1.2 on a iPhone 4s? The Pangu Jailbreak Tool ( http://en.pangu.io/ ) works like a charm for my iPhone 4S with iOS 7.1.2. Remember to back up your data before jailbreaking your iPhone.
How to adjust the system partition (C:) size of Windows?
Posted onThe disk management tools of Windows can adjust it to some level. But there are more space available as far as I can tell. How to further adjust the system partition (C:) size of Windows? You may check these tools: EASEUS Partition Master (free) Includes Partition Manager, Disk & Partition Copy Wizard and Partition Recovery
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How to find which hard drives a LVM volume uses?
Posted onHow to find which hard drives a LVM volume uses to decide which volume will be affected if a disk failes. You can use lvdisplay with the –maps option to display the the mapping of logical extents to physical volumes and physical extents: # lvdisplay –maps To map physical extents to logical extents, use #
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Fix the Grub issue with Windows 8 UEFI after installing Fedora 20
Posted onGrub fails to boot with Windows 8 UEFI after installing Fedora 20. The Grub entry for Windows 8 is: menuentry ‘Windows Boot Manager’ { chainloader /EFI/Microsoft/Boot/bootmgfw.efi boot } How to fix it? The set root= is missing. You probably can fix this by specifying the root manually: menuentry ‘Windows Boot Manager’ { insmod part_gpt set
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x86-64 instructions for floating-point comparisons
Posted onWhat are the x86-64 instructions for floating-point comparisons like the cmpq for quard-word integer comparison? The SSE3 extenstions provide two instructions for comparing floating values: Instruction Based on Description ucomiss S2, S1 S1 – S2 Compare single precision ucomisd S2, S1 S1 – S2 Compare double precision As with cmpq, they follow the GAS convention
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Video player for iPhone for uploading video files and watching them
Posted onWhich video player for iPhone is good for uploading video files from my computer and watching them? For example, I download some video files and would like to watch them on my iPhone on the go. I know iTune can do this. But I am on Linux and I want something easier. Many apps can
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How to download a youtube video to my computer?
Posted onHow to download a youtube video to my computer? You may use the ClipConverter.cc for downloading Youtube videos: http://www.clipconverter.cc/ How to download a YouTube video: Paste your YouTube URL at ‘Media URL’ and press Continue. Select the format and the options for the conversion. The default options are for most videos a good setting. Press
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How to erase disk partitions on U disks on Windows?
Posted onHow to erase disk partitions on U disks on Windows? Check the HDD LLF low level format tool: http://hddguru.com/software/HDD-LLF-Low-Level-Format-Tool/ It is free for personal usage. Run it as Adminiatrator and you can choose to erase partitions and MBR on the U disks. Be careful that the operation is is recoverable.
Setting up a VPN over SSH
Posted onSSH tunnel and port forwarding is great and convenient to use. But is it possible to set up a VPN like connection over SSH? If you are on Linux or Mac, you can use sshuttle: https://github.com/apenwarr/sshuttle If you are on Windows, you can use ProxyCap: http://www.proxycap.com/index.html Both are great software.