DVD Studio Pro - Stage 4: Calculating the Audio Allowances

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Calculating the Audio Allowances

Depending on your project, the audio may have a relatively minor effect on disc space.
It can also be challenging to determine the audio allowances because each video asset
can have up to eight audio streams, and each stream can be a different type and length.
The following table lists the typical bit rates for the common audio formats.

Bit rate

Audio format

192 kilobits per second (kbps) to 224 kbps

AC-3 stereo

384 to 448 kbps

AC-3 5.1 surround

754.5 kbps or 1509.75 kbps

DTS 5.1 surround

1536 kbps

PCM stereo 16 bits at 48 kHz

4608 kbps

PCM stereo 24 bits at 96 kHz

In the earlier example, video asset 1 has two audio streams, each 5174 seconds long. The
first stream is AC-3 5.1 surround, and the second is AC-3 stereo. The video asset 2 has
one audio stream 2735 seconds long, using 16-bit 48 kHz PCM audio. The motion menu
has an AC-3 stereo audio stream 17 seconds long. If your slideshow includes audio, you
also need to include that in the formula.

To calculate the storage required, you determine each video asset’s total audio bit rate
and multiply that by the duration.

Disc space

Bit rate



2.32 gigabits (Gbit)

448 kbps

5174 seconds

Video 1, AC-3 5.1

1.16 Gbit

224 kbps

5174 seconds

Video 1, AC-3 stereo

4.20 Gbit

1536 kbps

2735 seconds

Video 2, 16-bit 48 kHz

0.004 Gbit

224 kbps

17 seconds

Menu, AC-3 stereo

Total: 7.684 Gbit

As you can see, using PCM audio requires substantially more disc space than using a
compressed format like AC-3. See

Preparing Audio Assets

for more information on the

different audio formats.

Stage 5: