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How does bandwidth affect the frame rate, Some units in chapter, How does – ALLIED Vision Technologies Pike F-1600 User Manual

Page 288: Bandwidth affect the frame rate, Vised chapter, Chapter, Read chapter, Table 129: bytedepth

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How does bandwidth affect the frame rate?

PIKE Technical Manual V5.1.2

288

How does bandwidth affect the frame
rate?

In some modes the IEEE 1394b bus limits the attainable frame rate. According
to the 1394b specification on isochronous transfer, the largest data payload
size of 8192 bytes per 125 μs cycle is possible with bandwidth of 800 Mbit/s. In
addition, there is a limitation, only a maximum number of 65535 (2

16

-1) pack-

ets per frame are allowed.

The following formula establishes the relationship between the required
Byte_Per_Packet size and certain variables for the image. It is valid only for
Format_7.

If the value for BYTE_PER_PACKET is greater than 8192 (the maximum data
payload), the sought-after frame rate cannot be attained. The attainable frame
rate can be calculated using this formula:

(Provision: BYTE_PER_PACKET is divisible by 4):

ByteDepth based on the following values:

Formula 20: Byte_per_Packet calculation (only Format_7)

Formula 21: Maximum frame rate calculation

Mode

bit/pixel

byte per pixel

Mono8, Raw8

8

1

Mono16, Raw16

16

2

YUV4:2:2

16

2

YUV4:1:1

12

1.5

RGB8

24

3

Table 129: ByteDepth

BYTE_PER_PACKET

frame rate[1/s]

AOI_WIDTH

AOI_HEIGHT

ByteDepth [byte]

125 [μs]

=

frame rate

BYTE_PER_PACKET [byte]

AOI_WIDTH

AOI_HEIGHT

ByteDepth [byte]

125 [μs]

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