Thursday, January 30, 2014

ALSA and HDMI

ALSA could use alisa (aplay -L) to distinguish different sound card and device (aplay -l). Then each application need to decide which alisa is used to output sound. mplayer, aplay and other application could use alisa as options. But flash plugins generally only use default, see link

For HDMI audio output, first application need to know which card/device is for HDMI output and then use related alisa as output. But flashplugins in Linux could only use default as output, then it is needed to assign default to HDMI device, see Wiki in Archlinux

PCM slave is used to forward ALSA plugins to related sound card and device.

Background: there is no audio through HDMI when I connect my laptop with TV and use TV as screen for tv.sohu.com. I have to follow workaround from wiki.archlinux.org to reset default in .asoundrc. It is caused by flash only use default for output.

Sunday, January 12, 2014

Database

I read three manuals or tutorials for database recently: SQL, mongo and Berkeley DB. SQL is rational database which you could treat it as a bigger "excel". Berkeley DB is simply key to data database. And mongo is document database which handle special json like document.

Berkeley DB is popular database in Unix/Linux world. It is the successor for gdbm. Oracle bought Berkeley DB and developed it with more function like transaction (group command), concurrency (prevent write one record by two guys together) and SQL capacity.Since it is key-data database, it is very convinient to store contact with bdb.

Mongo is database for json like document. From my understanding, Mongo is optimized for distribution/cluster and index. It is all for big-data.

SQL is most popular database for nearly all things. In SQL, everything is organized as tables. Everything record is one row which has several values/attributions. Also you could link two tables together if they has common values/attributions. SQL is used everywhere: blog, news site, bank, schools.

Sunday, January 05, 2014

Summary for 2013

2013年对我而言是人生发生重大变化的一年: 结婚,买房,婚礼,蜜月旅行,老婆怀孕,工作上也发生了很多变化。

婚姻及怀孕

这一年最大的变化就是结婚了。从2013年1月领证,8月婚礼及其后的欧洲蜜月之旅,10月回新疆又小办了一次,一切都来的这么迅速及幸福。更大的惊喜是小宝宝在年底突然出,这也让生活完全呈现出另外一种幸福和紧张。可以说2014年的最大的希望就是小宝宝能顺利出生,妈妈和TA都健健康康的。

房子

房子终于在2013年尘埃落定。从2012年下半年开始看房到2013年3月过户,期间发生了很多曲折和辛苦。但最具有戏剧性的是,短短半年这套房子就增值了很多。我曾开玩笑的跟老婆说,从我们的经验看,房子是最具增值性的投资手段了。我曾经很确定地认为房价就是一个bubble,但现在也越来越怀疑这个conclusion了。

工作

2013年工作也发生了很大的变化。年初开始接触TDD node,去瑞典transfer;9月升senior; 年底LL从瑞典归来,部门组织架构调整,我做了3年之久的2k也将转出。由于TDD node的缘故,2013年中对于SW,RBS系统架构都有了更深的了解。

Social network

2013年主要的social network是微博和Google+。Google+由于GFW和帖子质量的问题,光顾的次数不多。可以说新浪微博占据了我大部分的闲暇时间。这一年朋友和同事圈立的帖子数量下降很大。但特定爱好群体的帖子质量和发帖数量都保持了稳定的水平。目前我关注的主要群体是医生及健身爱好者; 科学研究者(主要是生物类); 科普工作者;经济研究者; 码农。对于其它social network: twitter/facebook的帐号已经删除; 偶尔去newsmth看一眼网络武侠的讨论;QQ基本上不用; 目前很火的微信只是去土耳其出差时用过一段时间,回来之后就删除了。

Programming

2013年里继续使用linux。去土耳其出差期间用gnuplot和awk处理数据,极大的缩减了我处理数据的工作量; 年底开始用pygraphic画流程图,学习django和git。另外开始用python学习fft,数字滤波,这对我理解工作上的某些事情也有很大的帮助。由于GFW升级,ssh tunnel 和openvpn开始失效,目前主要使用shadowsock翻墙。

Science

这一年在科学学习上并无太多成就。2013年痴迷于pad游戏和微博,并没有看太多的科学书籍。主要还是通过微博浏览中医批判,反转基因批判,进化心理学及生物相关的微博。