ADV601LCJST View Datasheet(PDF) - Analog Devices
Part Name
Description
View to exact match
ADV601LCJST Datasheet PDF : 44 Pages
| |||
ADV601LC
Table II. ADV601LC Typical Quantization of Mallat Data
Block Data1
Mallat
Blocks
Bin Width
Factors
Reciprocal Bin
Width Factors
39
0x007F
0x0810
40
0x009A
0x06a6
41
0x009A
0x06a6
36
0x00BE
0x0564
33
0x00BE
0x0564
30
0x00E4
0x047e
34
0x00E6
0x0474
35
0x00E6
0x0474
37
0x00E6
0x0474
38
0x00E6
0x0474
31
0x0114
0x03b6
32
0x0114
0x03b6
27
0x0281
0x0199
24
0x0281
0x0199
21
0x0301
0x0155
25
0x0306
0x0153
26
0x0306
0x0153
28
0x0306
0x0153
29
0x0306
0x0153
22
0x03A1
0x011a
23
0x03A1
0x011a
5
0x0A16
0x0066
18
0x0A16
0x0066
12
0x0C1A
0x0055
20
0x0C2E
0x0054
19
0x0C2E
0x0054
17
0x0C2E
0x0054
16
0x0C2E
0x0054
14
0x0E9D
0x0046
13
0x0E9D
0x0046
6
0x1DDC
0x0022
9
0x1DDC
0x0022
3
0x23D5
0x001d
11
0x2410
0x001c
10
0x2410
0x001c
8
0x2410
0x001c
7
0x2410
0x001c
5
0x2B46
0x0018
4
0x2B46
0x0018
0
0xA417
0x0006
2
0xC62B
0x0005
1
0xC62B
0x0005
NOTE
1The Mallat block numbers, Bin Width factors, and Reciprocal Bin Width
factors in Table II correspond to the shading percent fill) of Mallat blocks in
Figure 8.
THE RUN LENGTH CODER AND HUFFMAN CODER
This block contains two types of entropy coders that achieve
mathematically loss-less compression: run length and Huffman.
The run-length coder looks for long strings of zeros and replaces
it with short hand symbols. Table III illustrates an example of
how compression is possible.
The Huffman coder is a digital compressor/decompressor that
can be used for compressing any type of digital data. Essentially,
an ideal Huffman coder creates a table of the most commonly
occurring code sequences (typically zero and small values near
zero) and then replaces those codes with some shorthand. The
ADV601LC employs three fixed Huffman tables; it does not
create tables.
The filters and the quantizer increase the number of zeros and
strings of zeros, which improves the performance of the entropy
coders. The higher the selected compression ratio, the more
zeros and small value sequences the quantizer needs to generate.
The transformed image in Figure 5 shows that the filter bank
concentrates zeros and small values in the higher frequency
blocks.
Encoding vs. Decoding
The decoding of compressed video follows the exact path as
encoding but in reverse order. There is no need to calculate Bin
Widths during decode because the Bin Width is stored in the
compressed image during encode.
PROGRAMMER’S MODEL
A host device configures the ADV601LC using the Host I/O
Port. The host reads from status registers and writes to control
registers through the Host I/O Port.
Table IV. Register Description Conventions
Register Name
Register Type (Indirect or Direct, Read or Write) and Address
Register Functional Description Text
Bit [#] or Bit or Bit Field Name and Usage Description
Bit Range
[High:Low]
0 Action or Indication When Bit Is Cleared (Equals 0)
1 Action or Indication When Bit Is Set (Equals 1)
Table III. Uncompressed Versus Compressed Data Using Run-Length Coding
0000000000000000000000000000000000000000000000000000000000000000000(uncompressed)
57 Zeros (Compressed)
–8–
REV. 0
|
|
Share Link: 