Toms Tech

Visit Audio Video Codec for more on audio and video codecs.

Visit Audio Codecs – What are they?

Audio codecs are defined as software applications of hardware devices (with the same kind of software) that can compress audio files and then decompress them. In fact, the codecs used for compression and decompression work with opposite principles, but they are quite similar to each other in the manner of their working.

The formats used by audio formats are any applicable digital audio formats that are commonly used. For transmission over the Internet, codecs can also compress and convert files into streaming audio formats.

The word ‘codec’ is derived from coding-decoding, which is what a codec does. It first codes the digital data into a small compressed form and then plays back the data by reconverting it into the original form.

Audio Codecs – How do they work?



Audio codecs work with the principle of audio compression. This is a process of reducing the size of an audio file so that it is covered within as few bits of data as possible. The idea is to remove all unnecessary sound bits and bundle them into a smaller format so that they are compressed. When the file needs to be played back, a decoding system is put into play which can expand the files again so that they can be played.

Lossless and Lossy Audio Codecs

There are two types of compression that audio codecs can perform. Based on that, they are called as lossless and lossy audio codecs.

Lossless audio codecs retain a copy of the original audio files before converting them, so that any kind of qualitative or quantitative loss becomes reversible. However, this also increases the size of the file even after compression. It is difficult to have a lossless audio codec that can compress an audio file below 50 to 60% of its original size.

Lossy audio codecs are those that do not retain any previous information. They compress the audio to the smallest size possible and transmit them where they are decoded to a playable size. However, there is a danger of loss of data because of the fact that there is no backup created. The brighter side of this is that lossy audio compressed files are substantially smaller in size. These can easily compress the files to 5 to 20% of their original size.

Today, most audio codecs available in the market are of the lossy type. Though they will cause a deterioration of the quality of the file, they are good for online transmission and even storing on discs. For that reason, people prefer lossy audio codecs over the lossless ones.

Audio Codecs – The Tradeoff

There is always a compromise involved when audio codecs are used. It is not possible to predict in advance how these files will be compressed and whether they will play at good quality upon being decompressed or not. This is especially because most codecs used today are lossless. Though this becomes ideal for sending digitally compressed audio files over the Internet, they also mar the original quality of the recording. Hence, these audio codecs are used only sparingly and only in areas that really require them.

Why not take your friends on a walk while they stay at home? It’s easy to do. Just grab that digital camera and head out to your favorite trail. Since you’ll be taking a lot of pictures, make sure your memory card can hold enough pictures; otherwise you’ll need a spare card, and why not bring along some extra batteries, just in case. You can carefully frame each shot, or, if you have a camera strap long enough, you can let the camera hang from your neck and shoot from there. Start with a shot of your car, the door being opened, the trailhead, and then start out.

Every twenty yards or so, take a picture. If you shoot nothing but straight ahead shots you can assemble them later into a stop-motion-frame effect slideshow. If you want to take some side shots or close-ups of flowers, etc., you’ll have to do some editing later. As you walk, keep in mind what you might be saying to your ‘imaginary’ trail partners. Later, when you assemble the slideshow, you’ll want to add a narrative.

You could also take your shots in a pattern: walk twenty yards, shoot 45 degrees to your left, one straight ahead, and one off to your right. Walk another twenty yards and repeat the pattern, over and over. You could vary the pattern of picture taking on different parts of the trail. Where the trail is thick with trees on the sides, just shoot straight ahead. If the trail circumscribes a lake or river, then shoot one towards the water, one towards the trail, and repeat.

When you come to a particularly scenic place, you could shoot a 360-degree pan. Simply start straight ahead; take note of what detail is in the upper right hand corner of your viewer, take the shot, then move that detail to the upper left corner and shoot; take note of any object in the upper right corner, move it to the left corner, shoot, and repeat until you are facing forward again. At the end of the hike, you might want to take a time-delay self-portrait. Set the camera on a safe, level surface, look through the viewfinder and note what’s in the frame and where you should stand; hit the delay button and run over and strike your best trailblazer pose. Review the shot to make sure you are in the picture! Now head on back home for the really fun part.

After you transfer all the pictures to your computer, take a program like Windows Movie Maker and load in your images; they should be pretty close to the right order. Once you get them arranged, decide how long you want to show each picture; set the length of the first one to this value and apply it to all the others. Make a note of the length of the entire show.

Now fire up a program like Avnex’s Voice Changer Software Diamond 5.0. With that little gem you can create an impressive narration to complete your slideshow. Try the voice morpher module. You can enrich your voice with just a few simple adjustments to sound like a professional voiceover talent. I like to drop the pitch and timbre just a few notches, and my voice comes out like a Darth Vader wannabe. Because you can add more than one sound file, think about adding some sound effects to the presentation as well. It’s always a good idea to adjust the volume of the sound effects to be softer than the narrative; you don’t want the sounds to overpower the vocal. Voice Changer can also allow you to alter your voice dynamically, so that you could add a second or even a third voice to the narrative. If your narrative comes out a little long or a little short, consider simply adjusting one or two or a few slide lengths, especially at the beginning or the end.

Once you’ve completed and saved the project, give your friends a call. Tell them you want to go hiking with them. Tell them to meet you at your house. When they arrive invite them in, and sit them down. When they ask what’s going on, start the slideshow! Be sure to have plenty of refreshments on hand, in case they get a little restless. I hope they enjoy the walk!

Do you remember using the Internet back when you had to dial in using a modem. If you are unlucky enough to still be using dial-up Internet access, I feel for you. The internet is a growing and dynamic entity and everyone will have broadband sooner or later.

Naturally companies try to offer access to internet in growing number of ways. Assuming the user has the correct hardware, a wi-fi account, and is in range of the transmitters, the service allows the user to connect to the internet at broadband speeds without the use of cables. Users can log on to the internet at these hotspots provided they have an account with the broadband supplier and the necessary wireless equipment, such as a wireless laptop or broadband-enabled mobile phone.

An extra phone is the only way to get calls that cannot be received due to the dial up connection. Fixed line operators are now incorporating wireless with their traditional phone services providing ease of having one device and one bill for both mobile and fixed line calls. You can take it out of your phone bill.

Broadband phone actually uses voice over internet protocol (VoIP) to carry phone calls through the internet. There are also a number of companies that has VoIP as a free service.

Digital Subscriber Lines, or DSL uses the existing customer phone lines to provide internet or intranet access to businesses and homes using high-speed broadband technology of varying levels. But even with all the technology that has gone into the making of the Internet, there seems to be more to be expected than has been seen. It’s easy to understand why; the technology industry defines it in different ways as well.

Just be sure you do not choose an ISDN line (because it is getting obsolete) or power line (because the technology is not mature, and it will be some years before the bugs are ironed out). The cheapest broadband deals allow for such technology to reach our homes for less than $10 per month.

Ok, on to the two major broadband access methods, cable and DSL. There is cable access, DSL access, satellite access. Although cable broadband internet is a whole lot faster than dial-up, I usually experience a slight delay when opening a webpage.

Perhaps most people do not notice the latency associated with cable internet, but it got my attention right away. So are cable television modems, which have similar speeds. Approximately 4 million people in the UK use ADSL with an extra 2 million using a cable connection, meaning 6 million people in the UK have an always-on internet connection.

The fact is that anything less than the speed supplied by a broadband cable has become inadequate for today’s internet users.

Providers

However it has emerged that broadband providers touting such products are not revealing the full story to their customers. The key will be for broadband providers to develop the services that broadband allows for, and to deliver them to as many households as possible. High-speed Internet services are growing in popularity because intense competition from broadband providers is continually driving the product exposure in the marketplace to new highs, and prices to new lows.

Connecting to the Internet for the first time in your home or office is as easy as securing a fixed telephone line (which you probably already have) and signing up to one of the dozens of Broadband Providers, like AOL and others.

Satellite

Bummer indeed, but you still have broadband Direct PC by satellite and it seems to make it through those clouds and so you can surf the NOAA website and get the latest results or watch video streams of the local TV station right. Broadband Internet by Satellite is about the coolest invention in the World and indeed it has helped the unconnected become connected even if they live in the middle of nowhere. Did you know you can get a special satellite antenna hooked up on your motor home or recreational vehicle that will enable you to get the Internet anywhere in North America.

Television

So they are bundling broadband with other products, such as home phone, digital television and mobile. The acronym is used to describe services which broadcast on-demand television programming to consumers, delivered via a broadband connection on normal telephone line to TV screens. Broadband television is a means of providing TV programs via the Internet.

Broadband Television is being hailed as the biggest change in the way we watch television since it was first invented.