Merge MP3 with Audacity

I was trying to merge several MP3 files into a single MP3 the other day. I thought VLC should be able to do the job and I did find instructions for that. However, the instructions mentioned a "Open Media" option that I don't have on my version of VLC on OS X (even after updated to latest) I know for sure Audacity can do that. However, moving the sound data so that it goes one file after another seems to be a lot of work. Thanks to this post. I found there is actually a very easy way to do so: 

1) File->Import->Audio (can multi-select)

2) Tracks->Align Tracks->Align End to End

3) Now you can export the whole thing to one MP3.

Isn't that simple? 

Amazon Kindle Create to other formats

To publish a book on Amazon, it seems that using its "native" tool Kindle Create would be a good idea. However, once your book is created in this tool, it is rather difficult to share a "soft copy" of this book for reviewers. Fortunately, there is a way to do so (thanks to this post) using two pieces of free software, to be precise, a reader and a plugin. The reader is Calibre while the plugin is KFX Input plugin. Before going to Calibre,  create a .kpf file in Kindle Create using the "Generate" function. After Calibre is installed, simply use "Preference > Plugins" to specify the downloaded plugin zip file. Then you can add your kpf file and then "Convert book." Choose your desired formats, e.g. PDF, DOCX or EPUB. At this point you can also add a cover image which will be the first page of your output. 

More Videos on Chromecast Google TV

I think I bought the Amazon FireTV in 2018 to replace my old Chromecast and after 3.5 years of services, it became a brick all of a sudden. Kodi has been great on the FireTV but it's not perfect. So it's time to try out the latest Chromecast Google TV, which is very much like the FireTV on which I can install apps like this. Of course external APK is always tricky on an Android system. 

First, the old instructions for the older Chromecast Google TV (i.e., those before the "Sky Blue" version) for turning on the Developers option no longer works. Now you need to download an app called "Developers Tool" from Google's App store first (thanks to reddit)  Then go to Settings->App->Security to allow installing APK from unknown source. 

Second, install "Send Files to TV" app on both your phone and Chromecast Google TV. Use your phone to download the APK you want (like the one mentioned above) and send to Chromecast Google TV (thanks to this post)

Third, install a File Manager (like the one from the previous link)

Finally you can open the APK in the File Manager and install it!

More videos on Fire TV

This is a follow-up to my post when I just bought the Fire TV stick. The app has of course become out-dated after 3 years but it's actually quite easy to update to the latest version thanks to this guide. However, the update would break some add-ons that relies on Python 2. Fortunately, the broken add-on was fixed. Here are the instructions for installing this fixed version. And this is for taking advantage of the availability of Python 3. 

尋根

不時和家人說笑：「我們都是蘇東坡的親戚呢」不過其實心底也頗有疑問：蘇東坡是四川人，我家則來自潮州。今天花了點時間Google: 首先從此文得知潮安蘇氏的祖先是後隴蘇氏，亦即是宋朝著名科學家蘇頌的後人，而蘇頌和三蘇同時代，蘇洵曾經和蘇頌相認同宗。而兩家族的祖先都是蘇武父親蘇建。

RSS Video feed on Fire TV

Basically you need to install this app and then add a video source. Unfortunately the latter post has a typo: the URL should start with rss:// instead of http:// It took me half an hour to figure out! And to display Chinese character in file name, you need to click the "System" icon, open "Interface Setting"->Skin->Fonts and change to "Arial based"

SSH to your iPhone without password

Previously I wrote about offline browsing which involves SSHFS that requires you type in the root password of your iPhone everytime. To save some typing, you could setup SSH public/private keys. Here are the steps.

On the host that you mount iPhone's filesystem, execute:
ssh-keygen -t rsa
which generates a public and a private key. The former is ~/.ssh/id_rsa.pub

On your iPhone
1) create a ~/.ssh directory and copy the above public key over. Name it as .ssh/authorized_key.
2) Uncomment the following line in your /etc/ssh/sshd_config:
AuthorizedKeysFile .ssh/authorized_keys

Now you could ssh (and thus sshfs) to your iPhone without password.