Skip to main content ↑ ↓
Topic: Using WMA and MP4 formats (Read 2466 times) previous topic - next topic

Using WMA and MP4 formats

If you are interested in sending your music over the Internet as a sound file (rather than as MIDI or NWC native format) that is more-or-less streamable over home phone modems, then read on:

Lately, I have been experimenting with adding environmental sounds (not music) to my web pages. I record them to WAV format. Then what?

WAV is too bulky to send over phone modems. Although MP3 format allows a choice of sound quality, the lower-quality options sound to me like garbage. This is especially true of enviromental sounds, for which background noise ends up sounding like gerbils in a billabong. Only the lowest-quality MP3 has much of a chance of making it at 56K modem speeds.

Windows Media Player native format is WMA. Microsoft offers a free Windows Media Encoder that will convert a WAV or MP3 sound into WMA format, at a choice of quality. I find that choosing monophic FM radio quality for 28K modem is adequate for my sounds.

With Quicktime 6, Apple has added MP4 format. When compressed to 20k sampling (the rough equivalent of the above WMA), the result is also acceptable. Note that MP4 is new, and the capability for file conversion is only available with that "Pro" upgrade (not free) that Apple nags you about. But a bonus is that the "Pro" player will also convert MIDI to WAV (or MP3 or MP4) without hassle.

The resulting WMA or MP4 files are about 1/3 the size of a mid-quality MP3.

Before you create any of these other audio formats, you must first convert your MIDI to WAV (or MP3, which usually means first converting to WAV).

Why would you want to send sounds rather than MIDI or NWC native format? Perhaps you want to add an outside audio track, or your voice. One way to do this is with the free "Audacity" sound editor from Sourceforge.net. Audacity will also convert WAV to MP3, and vice-versa.

For those who do not already know: MIDI contains program instructions that drive synthesized or sampled "instruments" that come from other files. Since the MIDI does not contain the instrument "sounds," MIDI files are small. When MIDI is converted to an audio format such as WAV, AIF, MP3, or MP4, the instruments are "played" and their sounds are merged. That's why audio file types are larger. Other than the Apple Quicktime 6 "Pro" Player described above, there are other ways to convert MIDI to WAV (but I haven't tried them, and the often-described method of using Winamp is a hassle).

If you want advice on how to convert MIDI to WAV (or MP3), use the forum search capability before you ask!
 

Re: Using WMA and MP4 formats

Reply #1 –
One other thing... The Windows Media Encoder is capable of "capturing" audio and/or video played by some other application in real-time. It will even capture sound played directly within NWC, and convert it to WMA format. But the easiest way to get a WMA from your NWC composition is to go through a MIDI intermediary, play the MIDI in one application, and capture it with the Encoder.

I am told (but do not know) that a WMA can be input to most music CD-ROM writer applications, rather than using an MP3 input.