Music, formats and storage

For the past 6 months I've been pondering about ripping and encoding my entire music-collection into a digital archive for both safe keeping and easy access. Earlier, I only encoded my favorite tracks, saving precious disk-space. But in these days, disk-space is plentiful, and encoding is pretty straightforward.

Only thing I couldn't decide, was which encoding-format to use. I've been a happy user of MP3-technology for well over 12 years, but, I have noticed glitches / crappy noise and disturbances in certain MP3-codecs (which vary a lot across different music-devices / systems).

So eventually, it became a stand-off between FLAC and Vorbis. And since I really can't hear the difference between a 320kbit OGG and a FLAC file, the choice pretty much fell on Vorbis. Vorbis is also known as "Ogg Vorbis", an open-source audio-codec accepted by almost every modern MP3-compliant device available today (Vorbis can be encoded in bitrates ranging from 32 to 500 kbit/s, and is globally voted as the best sounding codec at comparative bitrates of 128-320kbit/s).

Beginning with my precious electronica music, I converted all tracks to 320kbit Constant BitRate (CBR) Ogg Vorbis files. Totaling 624 tracks, averaging 4 minutes, came to a total of 4.4 GigaBytes (which I'm currently listening to through Rhythmbox as I type :p). In other words, my ENTIRE electronica collection on ONE DVD+/-R disc! AWESOME!

Calculating the rest of my collection, I should be able to compress it all on 8-9 DVD+/-R discs.

I really understand why Spotify® uses Ogg Vorbis, it keeps a high quality of sound as well as saving disk-space, and from what I can tell, it doesn't strain the CPU very much either.

What makes me smile, is that EVERY device in my room can play Vorbis ;) My PlayStation3 system, my Asus Eee netbook running Ubuntu, my Pioneer DVD-player and my HTC Desire Android smart-phone ;D

Open-Source FTW! ;D

Satellite-TV

OK. This post should not surprise anyone following my blog.

I'm elaborating on my knowledge of geostationary communication devices.

i.e. satellites

First off, satellites orbit a space-region known as the "Clarke Belt", approx. 22.300 miles (35.888 km) above the equator. Each satellite has a number of 'transponders' (transmitter-responder), and each of these transponders carry a signal back to earth. These signals are carried either on "C band", "Ku Band" or "Ka Band" which signifes what frequency is used to transmit the signal. After travelling through our atmosphere, over 20.000 miles, a dish is able to recieve them.

A satellite-dish can be everything from 18" (inches) to 9' (feet) across. It's main purpose is to be a collector/reflector to catch a microwave-satellite-signal, and aim it towards the 'feedhorn'. The feedhorn recieves the signal and sends it to the 'LNB' (Low Noise Block). The LNB amplifies the signal, and converts it to a frequency more suitable for transmission over a cable, also known as an 'IFL' (Intra-Facility Link). The IFL then carries the signal to the satellite reciever/decoder.

In cases where the signal is digital video broadcasting (DVB), it is usually digitally encoded, and the reciever/decoder has to decode the signal before it can be viewed/used. This also enables satellite-feed vendors to offer more channels over the same bandwidth as used in analogue systems where the channel-capacity is limited by actual transmission-capacity.

The standard audio/visual encoding used in DVB is one of either MPEG2 or MPEG4.

Links:

http://www.tech-faq.com

Just a little side-note on the 'smartcards' used in DVB-transmission and decoding. Smartcards have always, since the beginning of satellite-TV, been the authentication-token used to retrieve encryption-keys for encrypted streams, or simply as an identification-device to identify the recieving party as a valid customer.

Early in the race, these cards were merely electronic storage-chips used for ID information. But after years of development, they incorporate a range of security technologies of which the card-vendors have licensed as  proprietary intellectual property.