AC3 to AIF: Convert Audio from AC3(Dolby Digital AC-3 Audio) to AIF(AIFF/AIFC Apple Audio) with River Past Audio Converter, AC32AIF converter, conversion

What is AC3?

Dolby Digital, formerly known as AC-3, is a digital audio compression format. Dolby Digital takes advantage of how the human ear processes sound. When coding noise is close to the frequency of an audio signal, that audio signal masks the noise so that the human ear hears only the intended audio signal.

Dolby Digital is used with digital versatile discs (DVDs), in North America only. European DVD's use MPEG audio instead.

Dolby Digital provides five full-bandwidth channels, front left, front right, center, surround left, and surround right, for true surround sound quality. A low frequency effect (LFE) channel is included that provides the sound needed for special effects and action sequences in movies. The LFE channel is one-tenth of the bandwidth of the other channels and is sometimes erroneously called the subwoofer channel. This multichannel scheme is known as 5.1 channel.

To convert AC-3 audio to other formats in River Past software, please have AC-3 Decoder filter installed.

What is AIF?

Short for Audio Interchange File Format, a common format for storing and transmitting sampled sound. The format was developed by Apple Computer and is the standard audio format for Macintosh computers. It is also used by Silicon Graphics Incorporated (SGI).

The AIFF format is uncompressed so AIFF files tend to be large. However, there is another format called AIFF-Compressed (AIFF-C or AIFC) that supports compression ratios as high as 6:1.

AIFF files generally end with an .AIF or .IEF extension.

AIFC files generally end with an .AIFC extension.

AIFF and AIFC are standard audio format used on MacOS systems. AIFF is not compressed. AIFC is compressed.

To encode AIF audio, please make sure Apple QuickTime is installed.

Launch River Past Audio Converter

Once River Past Audio Converter is installed properly, launch Audio Converter.

Add File

Click on the "Add File" button on the tool bar. The standard file open dialog appears. Select "AC3 - Dolby Digital" in its "Files of type" combo box.

Select the file you want to convert and click "Open". The file will be added to the conversion file list.

Note: To convert from AC-3 files, you must have open source AC-3 decoder installed.

Once the AC-3 Decoder Filter is installed, you will also find a AC-3 Control Panel in your (Windows) Start | Settings | Control Panel area. It allows you to change the settings for the decoder. Often, you may find the default volume from the decoder is lower than desired and it is necessary to adjust the volume in this control panel.

If you cannot add the AC3 file, please verify your AC-3 Decoder filter installation.

River Past Audio Converter

Select output format

Use the setting panel on the bottom of the window to control the output format. Click on the toggle to the left of the "Format" label to expand the panel. Select "AIF - Audio Interchanged File Format" as the "Audio Type".

Troubleshoot

If you don't see the AIF output option, you have a problem with your QuickTime installation.

You need to have the latest QuickTime installed. Occasionally, QuickTime may be corrupted. In any case, reinstall QuickTime should fix this problem.

You can change the compressor, and depending on the compressor, you can change the sample rate, channel (stereo or mono), bits/sample, and bitrate.

When "16 bit LPCM" or "16 bit PCM" is selected as the "Compressor", the file is uncompressed, and satisfy the original AIFF specification. When other compressors are used, the file is compressed and is considered to be an AIFC file.