Frame Rates - AVT Pike Technical Manual

Video formats, modes and bandwidth

Frame rates

Note Configuration
To configure this feature in an advanced register see Chapter
Autofunction AOI
An IEEE 1394 camera requires bandwidth to transport images.
The IEEE 1394b bus has very large bandwidth of at least 62.5 MByte/s for
transferring (isochronously) image data. Per cycle up to 8192 bytes (or
around 2000 quadlets = 4 bytes@ 800 Mbit/s) can thus be transmitted.
Note All bandwidth data is calculated with:
1 MByte = 1024 kByte
Depending on the video format settings and the configured frame rate, the
camera requires a certain percentage of maximum available bandwidth.
Clearly the bigger the image and the higher the frame rate, the more data is
to be transmitted.
The following tables indicate the volume of data in various formats and
modes to be sent within one cycle (125 µs) at 800 Mbit/s of bandwidth.
The tables are divided into three formats:
Format
Format_0
Format_1
Format_2
Table 82: Overview fixed formats
They enable you to calculate the required bandwidth and to ascertain the
number of cameras that can be operated independently on a bus and in which
mode.
on page 287.
Resolution
up to VGA
up to XGA
up to UXGA
max. Video Format
640 x 480
1024 x 768
1600 x 1200
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