Matrox MXO2 PCIe Host Adapter - Manual (Page 284)

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Chapter 19, Using the Matrox MAX H.264 Codec with Adobe Software
specify a high target data rate to avoid having frames of blocky video in
your file.
¦ Note When creating Matrox .264 files for Blu-ray Disc authoring, it’s
recommended that you use a constant bit rate.
• Target/Minimum/Maximum data rate Use these sliders to select
your desired data rate. The higher the target data rate you select, the
better the video quality will be. Only the
Target data rate will be
available if you selected Constant bit rate (CBR) . If you selected
Variable bit rate (VBR) , all three sliders will be available so that you
can set the target, minimum, and maximum data rates for the video
compression.
¦ Note When customizing the settings for a Matrox .264 file, be aware that
Matrox .264 files that have a data rate higher than about 30 Mb/sec may require
transcoding in Adobe Encore. The maximum H.264 level and data rate
accepted by Adobe Encore for Blu-ray Disc authoring with audio and video
is level 4.1 at 35 Mb/sec.
• Source video complexity (Variable data rate only) Specifies the
complexity level of your source video. A complex video can be defined
as containing scenes with many colors, sharp edges, or transitions. The
Matrox MAX H.264 codec uses this setting to determine how much
compression is required in order to deliver high-quality video at your
specified target data rate. The default setting (15) is suitable for most
moderately complex videos. For simpler or more complex videos, you
may need to adjust this setting to obtain the highest-quality encoding
possible while respecting your target data rate. If the size of your
encoded video is good but the quality can be improved, lower the
complexity level setting. Your video will then be encoded with less
compression. If the quality of your encoded video is good but the size
is larger than expected, raise the complexity level setting. Your video
will then be encoded with more compression. In any case, you may
need to try different settings to get your desired results.
• Sample rate Determines how frequently the Matrox MAX H.264
codec verifies the current data rate while encoding and compares it to
your selected target data rate. If a discrepancy exists between the
current and target data rates, the current data rate is adjusted as
specified by the
Data rate adjustment setting (see below).
• Data rate adjustment When the current encoding data rate does not
match your specified target data rate, this setting determines how
quickly the current data rate is adjusted to reach the target data rate. A
gradual adjustment produces smoother transitions than a quick
adjustment.