Altera Video and Image Processing Suite User Manual

Page 43

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The width and height values are the dimensions of the video data packets that follow. The width refers to

the width in pixels of the lines of a frame. The height refers to the number of lines in a frame or field. For

example, a field of interlaced 1920×1080 (1080i) would have a width of 1920 and a height of 540, and a

frame of 1920×1080 (1080p) would have a width of 1920 and a height of 1080.
When a video data packet uses a subsampled color pattern, the individual color planes of the video data

packet have different dimensions. For example:
• 4:2:2 has one full width, full height plane and two half width, full height planes

• 4:2:0 has one full width, full height plane and two half width, half height planes
In these cases, you must configure the width and height fields of the control data packet for the fully

sampled, full width, and full height plane.
The interlacing value in the control packet indicates whether the video data packets that follow contain

progressing or interlaced video. The most significant two bits of the interlacing nibble describe whether

the next video data packet is either progressive, interlaced field 0 (F0) containing lines 0, 2, 4.... or

interlaced field 1 (F1) containing lines 1, 3, 5... 00 means progressive, 10 means interlaced F0, and 11

means interlaced F1.
The meaning of the second two bits is dependent on the first two bits. If the first two bits are set to 10 (F0)

or 11 (F1), the second two bits describe the synchronization of interlaced data. Use the synchronization

bits for progressive segmented frame (PsF) content, where progressive frames are transmitted as two

interlaced fields.
Synchronizing on F0 means that a video frame should be constructed from an F1 followed by an F0.

Similarly, synchronizing on F1 means that a video frame should be constructed from an F0 followed by an

F1. The other synchronization options are don't care when there is no difference in combining an F1 then

F0, or an F0 then F1. The final option is don't know to indicate that the synchronization of the interlaced

fields is unknown. The encoding for these options are 00 for synchronize on F0, 01 for synchronize on F1,

11 for don't care, and 10 for don't know.
Note: The synchronization bits do not affect the behavior of the Deinterlacing IP cores because the

synchronization field is fixed at compile time. However, they do affect the behavior of the Frame

Buffer IP core when dropping and repeating pairs of fields.

If the first two bits indicate a progressive frame, the second two bits indicate the type of the last field that

the progressive frame was deinterlaced from. The encoding for this is 10 for unknown or 11 for not

deinterlaced, 00 for F0 last, and 01 for F1 last.

Table 2-7: Examples of Control Data Packet Parameters

Parameters

Description

Type

Width

Height

Interlacin

g

15

1920

1080

0011

The frames that follow are progressive with a

resolution of 1920×1080.

15

640

480

0011

The frames that follow are progressive with a

resolution of 640×480.

2-16

Control Data Packets

UG-VIPSUITE

2015.05.04

Altera Corporation

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