Target options – Grass Valley ProCoder 3 User Manual

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ProCoder 3

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Using ProCoder

Helpful Hints

ProCoder

Reference

Glossary

Index

153

Target Options

Number of passes

For VBR encoding, select 1 pass or 2 pass encoding.

1 pass

Single-pass VBR encoding varies the bitrate on-the-fly, starting at
the specified bitrate, increasing toward the specified maximum in
complex segments and decreasing toward the specified minimum
in less complex segments. In general, single-pass VBR output will
be as-large or larger than CBR output at the same video bitrate.

2 pass

Two-pass VBR performs an analysis pass before the encoding
pass. The analysis pass determines the best bit allocation for the
encoding pass. The actual bitrate varies between the specified
minimum and maximum bitrates. The increases and decreases in
bitrate are balanced to keep the average bitrate to the specified
video bitrate.

Max Bitrate(kbps)

Specifies the maximum bitrate in thousands of bits per second for non-CBR encoding.
The encoded bitrate will not exceed the maximum bitrate.

Min Bitrate(kbps)

Specifies the minimum bitrate in thousands of bits per second for non-CBR encoding.
The encoded bitrate will not drop below the minimum bitrate.

Quantization Level

The Quantization Level determines the picture quality for CQ encoding. Higher
quantization levels provide better picture quality but require more bits to encode.

Reservoir Buffer Size (KB)

Valid only in 1-pass VBR mode. The output file size is at least [average bitrate] *
[duration] [Reservoir Buffer Size].

Expense Buffer Size(KB)

Valid only in 1-pass VBR mode. The output file size is at most [average bitrate] *
[duration] + [ExpenseReservoir Buffer Size].

Profile/Level

Determines the profile and level compliance of the MPEG output. The profile and level
impose restrictions on various parameters in order to guarantee compatibility with
MPEG hardware devices.

Put Sequence Headers on each GOP

Enable this option to add sequence headers at each GOP. Some applications require
sequence headers at every GOP.

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