Merely by a series of clicks, a fashionable ringtone format will be provided by our AU to M4A Converter!
The AU file format is a simple audio file format introduced by Sun Microsystems. The format was common on NeXT systems and on early Web pages. Originally it was headerless, being simply 8-bit µ-law-encoded data at an 8000 Hz sample rate. Hardware from other vendors often used sample rates as high as 8192 Hz, often integer factors of video clock signals. Newer files have a header that consists of six unsigned 32-bit words, an optional information chunk and then the data (in big endian format).
M4A, widely used as a ringtone format, refers to MPEG-4 Part 14 or MP4 file format, formally ISO/IEC 14496-14:2003, is a multimedia container format standard specified as a part of MPEG-4. It is most commonly used to store digital video and digital audio streams, especially those defined by MPEG, but can also be used to store other data such as subtitles and still images. Like most modern container formats, MPEG-4 Part 14 allows streaming over the Internet. A separate hint track is used to include streaming information in the file. The official filename extension for MPEG-4 Part 14 files is .mp4, thus the container format is often referred to simply as MP4.
How to convert?
Step 1 Add video or audio formats
Press Add to add the AU files you want to convert, then select m4a as the output format.
Step 2 Edit the file (Optional)
Press to play the files and the timer will start to work. Press to stop.
This feature is designed for you to measure your favorite segment.
When you want to designate the segment, you can press to set starting time and ending time.
Press to listen to the selected segment.
Step 3 Customize the audio (Optional)
As can be seen from the diagram, the panel allows you to set the expected volume and output format of the audio, and to customize the sample rate, Bit rate and channels the audio will contain.
Press to listen to the audio.
Step 4 Customize the metadata information (Optional)
We can see from the picture that the metadata information of the output audio, such as title, author, copyright, comment, album, track, can be customized merely by typing in what you want to display!
Step 5 Get your cool melody
When all settings are completed, just press Start Button to gain your favorite m4a from your output directory soon.