Questions and answers.
How 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…
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,…
How 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…
I’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 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.
I 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…
How 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…
How 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 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 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…
The 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…
How 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.
I wanna migrate leveldb (code.google.com/p/leveldb) to my github repository. Create a new repo on github.com with this link https://help.github.com/articles/creating-a-new-repository git clone https://code.google.com/p/ project-name.git Set the remote origin url as follows: git remote set-url origin https://github.com/ username/ repo-name.git git pull to pull the latest. git push origin master after making local changes. This is the original…
What 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…
Grub 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…
How 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 #…
How 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.
How 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…
Which 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…
How to replacing a string with another string with newline in Emacs? For example, to replace: good editor with good editor: Emacs What you need is actually to input a newline in Emacs: C-q C-j C-q is for quoted-insert, and C-j is a newline (0xa).