Panasonic WJ-HD316 Specifications page 2

As a cutting edge core technology, the WJ-HD300 Series provides proprietary algorithm
for high picture quality and high data compression. The new technology dramatically
compresses image data size while retaining high picture quality.
The WJ-HD300 Series enables higher disk saving and extended capability.
In addition, the new compression realizes higher ips (image per second)
live monitoring/playback and improved downloading speed via a network.
Intra-field Compression
New algorithm compresses the entire screen, and reduces artificial
distortions and noise compared to conventional compression.
Conventional Compression
Conventional intra-field type algorithm divides a picture to small blocks for the compression
process. Since it would be difficult to maintain continuity of compression between blocks, block
pattern distortion is noticeable. In addition, transition noise, which would degrade sharpness of
the edge signal, could be observed at high compression.
Division into
Playback
Original image Compression
De-compressed image
Blocks
1 block
8 x 8 pixels
WJ-HD300 Series Compression
The entire screen is compressed after being divided into high- and low-frequency elements.
The result is significantly reduced artificial distortion and noise that are inherent in conventional
systems.
Original image Extraction of Elements Compression
High-Frequency Elements
(Edges signal of Objects)
Low-Frequency Elements
(Full Frame Compression)
Detail
High pass filter
D1
Block and transition
D2
noise are visible.
Playback
De-compressed image
D1-4 D2-4 D3-4
D1-3 D2-3 D3-3
D1-2 D2-2 D3-2
D1-1 D2-1 D3-1
Conventional artificial
distortion and noise
are reduced.
High compression by eliminating redundant data between adjacent fields.
Conventional Compression
Images from a camera are compressed
field by field.
Field 4
Field 3
Field 2
Field 1
Approximation
All fields are independently compressed.
Low pass filter
A1
A2
D3 A3 • Accurate compression processing for sharp edge image areas.
• High speed temporal transforms processing. (Compression processing
among four (4) fields)
D4 A4
Compression Processing among Four (4) Fields
(Conditional Refresh Compression)
Temporal Transforms
(Movement Level)
movement : None D1-None
D4-4 A4-4
movement : Low D1-Low
D4-3 A4-3
D4-2 A4-2
movement : Mid D1-Mid
D4-1 A4-1
movement : High
D1-High
Inter-field Compression among Four (4) Fields
WJ-HD300 Series Compression
Data calculation within four (4) field images (called "Temporal Transforms" ), outputs data according to the
amount of movement; "No Movement," "Slow Speed Movement," "Medium Speed Movement," and "High Speed
Movement." As shown below, redundant data can be reduced through this compression process.
Field 4
Processing of
Movement
Compressed
Extraction of elements
with no movement
field by field
Field 3
Extraction of elements
with slow-speed
movement
Field 2
Extraction of elements
with medium-speed
movement
Field 1
Extraction of elements
with high-speed
movement
High efficiency is ensured since redundant data is not only within
the same field ("Intra-Field"), but also between fields ("Inter-Field").
New Compression Algorithm is Embedded into Proprietary LSI Chip
• Flexible compression settings for
independent cameras.
The proprietary compression chip
provides a combination of high picture
quality and high compression
with 60ips (image per second)
real time image processing.
Output
Half the data, the same picture quality
HEADER
Further disk saving, longer
recording time, and high
D2-None D3-None D4-None A4-None
image quality is realized
as shown below.
D2-Low D3-Low D4-Low A4-Low
D2-Mid D3-Mid D4-Mid A4-Mid
D2-High D3-High D4-High A4-High
Compression mode
Mode A
Mode B
(Conditional Refresh Compression)
Only this data
needs to be
compressed.
40KB
Conventional
30KB Compression
Mode B
20KB
Mode A
10KB
WJ-HD300 Series
New Compression
Super Fine Fine Normal Extended
Compression Mode
Algorithm Features
Intra + Inter field Temporal transforms among 4 fields
Intra field only Field by field compression