CN101634702A - Fraction bit rate BAQ method based on Lloyd-Max quantizer - Google Patents
Fraction bit rate BAQ method based on Lloyd-Max quantizer Download PDFInfo
- Publication number
- CN101634702A CN101634702A CN200810117048A CN200810117048A CN101634702A CN 101634702 A CN101634702 A CN 101634702A CN 200810117048 A CN200810117048 A CN 200810117048A CN 200810117048 A CN200810117048 A CN 200810117048A CN 101634702 A CN101634702 A CN 101634702A
- Authority
- CN
- China
- Prior art keywords
- lloyd
- standard deviation
- data
- bit rate
- blocks
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Landscapes
- Compression, Expansion, Code Conversion, And Decoders (AREA)
Abstract
The invention discloses a fraction bit rate BAQ method based on a Lloyd-Max quantizer, which comprises the following steps: partitioning sampled signals into blocks, and applying a recursion mode to perform running water treatment between the blocks; solving the amplitude equalizing value of each partitioned sampled signal; mapping the obtained amplitude equalizing value into a standard deviation; adopting the standard deviation to standardize the partitioned sampled signals; and adopting the Lloyd-Max quantizer to quantize the partitioned sampled signals after standardization. The method provides more optional fraction bit rates compared with the conventional integer bit rates, and by using the method, more compression scheme selection bases are provided for the design of a satellite-borne synthetic aperture radar system for satisfying the application requirements of different users, so the optional data rate with the maximum limit and the obtain of good middle points for the users with different application abilities are achieved, and the application requirements of the different users are further satisfied.
Description
Technical field
The present invention relates to satellite-borne SAR compressing original data technical field, relate in particular to a kind of fraction bit rate BAQ method based on the Lloyd-Max quantizer.
Background technology
The satellite-borne SAR compressing original data is to solve the effective way that data transfer bandwidth on mass data that satellite-borne SAR obtains and the star is difficult to matching problem.At present, although compression algorithm is of a great variety on the star, the compromise performance complicacy hard-wired of considering compression algorithm with it, can practicality have only the block adaptive quantization algorithm (Block Adaptive Quantization, BAQ).The core quantizer of this algorithm is the Lloyd-Max quantizer.
Traditionally, the BAQ algorithm all can only be realized the integer bit rate, as the 1bit/ sampled point, and 2bits/ sampled point or the like.When the systematic bits rate is between optional integer bit rate, then can only select lower bit rate downwards to guarantee that total data transfer rate is less than data transmission system bandwidth on the star.But the quantizing distortion that less bit rate causes is bigger, particularly under the application prerequisite that interferometry, moving-target detection etc. is had relatively high expectations to the phase distortion degree, need obtain good compromise under optional data rate and user's different application ability.Therefore, be necessary to study the fraction bit rate algorithm, so that the more more options between the integer bit rate to be provided.
Summary of the invention
(1) technical matters that will solve
In view of this, fundamental purpose of the present invention is to provide a kind of fraction bit rate BAQ method based on the Lloyd-Max quantizer, so that the user to the performance requirement of compression algorithm and can realize obtaining between the ratio of compression better compromise, selects for SAR system compresses conceptual design provides widely.
(2) technical scheme
For achieving the above object, the invention provides a kind of fraction bit rate BAQ method based on the Lloyd-Max quantizer, this method comprises:
Sampled signal is carried out piecemeal, use the recursion mode at interblock and carry out stream treatment;
Try to achieve each partitioned sampled signal amplitude equalizing value;
The amplitude equalizing value of trying to achieve is mapped as standard deviation;
Adopt this standard deviation that partitioned sampled signal is carried out standardization;
Partitioned sampled signal after adopting the Lloyd-Max quantizer to standardization quantizes.
In the such scheme, there are mapping relations one by one in the amplitude equalizing value of described partitioned sampled signal and standard deviation.
In the such scheme, this standard deviation of described employing is carried out standardization to partitioned sampled signal, be that the standard deviation that adopts the recursion mode that the n+2 blocks of data is used the n+1 blocks of data is carried out standardization, the n+3 blocks of data is used the standard deviation of n+2 blocks of data and carried out standardization, the n+4 blocks of data is used the standard deviation of n+3 blocks of data and carried out standardization, the rest may be inferred, uses the standard deviation of 2n-1 blocks of data until the 2n blocks of data and carry out standardization.
In the such scheme, the partitioned sampled signal of described application Lloyd-Max quantizer after to standardization quantizes, be different from traditional Lloyd-Max quantizer with an integral number power quantization level of 2 as quantizer, but with the Lloyd-Max quantizer of several quantization levels naturally as quantizer, making bit rate is fraction bit rate.
(3) beneficial effect
From technique scheme as can be seen, the present invention has following beneficial effect:
This fraction bit rate BAQ method provided by the invention based on the Lloyd-Max quantizer,, can be than the more optional fraction bit rate of traditional integer bit rate.Utilize the present invention, to select according to the application demand that satisfies different user for spaceborne synthetic aperture radar (SAR) system design provides more compression scheme, realized obtaining good compromise under the optional data rate and user's different application ability to greatest extent, and then satisfied the application demand of different user.
Description of drawings
Fig. 1 is the process flow diagram of the fraction bit rate BAQ method based on the Lloyd-Max quantizer provided by the invention.
Fig. 2 A, B are the branch interblock recursion handling principle figure of prior art.
Fig. 3 is the block data amplitude equalizing value and the standard deviation mapping relations of prior art.
Fig. 4 is the optional bit rate synoptic diagram of mid-score bit rate BAQ algorithm of the present invention.
Embodiment
For making the purpose, technical solutions and advantages of the present invention clearer, below in conjunction with specific embodiment, and with reference to accompanying drawing, the present invention is described in more detail.
The present invention realizes fraction bit rate BAQ method by the Lloyd-Max quantizer threshold level and the quantization level of the integral number power of selection non-2.
As shown in Figure 1, Fig. 1 is the process flow diagram of the fraction bit rate BAQ method based on the Lloyd-Max quantizer provided by the invention, and this method specifically comprises: sampled signal is carried out piecemeal, use the recursion mode and carry out the interblock stream treatment; Try to achieve each partitioned sampled signal amplitude equalizing value; The amplitude equalizing value of trying to achieve is mapped as standard deviation, adopts this standard deviation that partitioned sampled signal is carried out standardization (or claiming normalization); Partitioned sampled signal after adopting the Lloyd-Max quantizer to standardization quantizes.
Wherein, the orientation please refer to shown in Fig. 2 A to the principle of recursion mode stream treatment.For the standard deviation solution procedure of data in the simplified block, can adopt the amplitude equalizing value of finding the solution data in the piece, Nonlinear Mapping is the method for standard deviation then, mapping curve is as shown in Figure 3.During specific implementation, because there are mapping relations one by one in the amplitude equalizing value and the standard deviation of data in the piece, therefore the amplitude equalizing value that only needs to find the solution data in the piece gets final product, the mapping process of standard deviation is implied in the coding schedule, be that the address search coding schedule is realized quantizing and coding promptly with the amplitude equalizing value of data in the piece, and needn't the basis of calculation is poor separately again.
For convenience of description, be that 3 pulses are example with the orientation to block size.Shown in Fig. 2 B, ask for the amplitude equalizing value a of data in each height piece respectively, b, c, d ..., then a is estimated as the amplitude equalizing value of second sub-piece that b estimates as the amplitude equalizing value of the 3rd sub-piece, and handles with this order recursion.
Carrying out the standardization of recursion flowing water with 4 blocks of data is embodiment, and this 4 blocks of data is 8 bit AD samples, supposes that the sampled data number is 8 in each piece, and then this 4 blocks of data and amplitude equalizing value are as shown in table 1.
| Data block | Sampled value | Amplitude equalizing |
| Data block | ||
| 1 | ??8；42；-75；-30；-17；-78；-85；59 | ??49.25 |
| Data block 2 | ??0；-42；51；14；-64；85；18；94 | ??46 |
| Data block 3 | ??72；-44；-83；-5；-22；-54；31；95 | ??50.75 |
| Data block 4 | ??40；-39；35；-71；5；-128；-32；29 | ??47.25 |
Table 1
As shown in table 1, it is 64.36,59.7453,66.5605,61.4973 that the amplitude equalizing value of data block 1～4 can be mapped to standard deviation by the mapping relations among Fig. 3.
Then, adopt this standard deviation that partitioned sampled signal is carried out standardization.This standardisation process is that the standard deviation that adopts the recursion mode that the n+2 blocks of data is used the n+1 data block is carried out standardization, the n+3 blocks of data is used the standard deviation of n+2 data block and carried out standardization, the n+4 blocks of data is used the standard deviation of n+3 data block and carried out standardization, the rest may be inferred, uses the standard deviation of 2n-1 data block until the 2n blocks of data and carry out standardization.
That is, use the recursion mode standard deviation 59.7453,66.5605,61.4973 of data block 2,3,4 application data block successively 1,2,3 is carried out standardization, the results are shown in table 2 (data block 1 needn't be handled) here, after the standardization.
| Data block | Sampled value |
| Data block 2 | ??0；-0.7030；0.8536；0.2343；-1.0712；1.4227；0.3013；1.5733 |
| Data block 3 | ??1.0817；-0.6611；-1.2470；-0.0751；-0.3305；-0.8113；0.4657； ??1.4273 |
| Data block 4 | ??0.6504；-0.6342；0.5691；-1.1545；0.0813；-2.0814；-0.5203； ??0.4716 |
Table 2
Data after the standardization are used the Lloyd-Max quantizer and are quantized., be different from traditional Lloyd-Max quantizer with an integral number power quantization level of 2 herein as quantizer, but with the Lloyd-Max quantizer of several quantization levels naturally as quantizer, making bit rate is fraction bit rate.Here, the quantization level number of Lloyd-Max quantizer is not only 2 integral number power, but selects the natural number value.With this, constitute fraction bit rate.Optional fraction bit rate synoptic diagram as shown in Figure 4, the quantization level number that between traditional integer bit rate, adds the natural number value, constituted fraction bit rate, obviously traditional B AQ algorithm is the special case of algorithm of the present invention, algorithm of the present invention had both comprised the integer bit rate BAQ, comprised fraction bit rate BAQ again.
Getting natural number 2～16 with the quantization level number is embodiment, and its optional fraction bit rate is as shown in table 3 (supposes that the quantization level number is N, then 2
M=N, M are corresponding bit rate).
Table 3 the 2nd row have provided the signal to noise ratio (S/N ratio) (Signal to Noise Ratio SNR) of the standard gaussian signal being carried out optimum scalar quantization under the corresponding bit rate, during practical application, can carry out bit rate according to this form and select.
With 1.585 bits is embodiment, and the sampled data after his-and-hers watches 2 standardization quantizes, and the threshold level and the quantization level of 1.585 bit correspondences are as shown in table 4.
| The bits/ sampled point | ??SNR(dB) |
| ??1 | ??4.4208 |
| ??1.585 | ??7.2302 |
| ??2 | ??9.2519 |
| ??2.3219 | ??10.958 |
| ??2.585 | ??12.323 |
| ??2.8074 | ??13.559 |
| ??3 | ??14.592 |
| ??3.1699 | ??15.572 |
| ??3.3219 | ??16.437 |
| ??3.4594 | ??17.213 |
| ??3.5850 | ??17.813 |
| ??3.7004 | ??18.498 |
| ??3.8074 | ??19.165 |
| ??3.9069 | ??19.672 |
| ??4 | ??20.230 |
Table 3
| Threshold level | Quantization level |
| ??-0.612 ??0.612 | ??-1.224 ??0 ??1.224 |
Table 4
Threshold level and the quantization level that provides according to table 4 then, data block 2～data block 4 is carried out the table 5 that the results are summarized in of scalar quantization in the his-and-hers watches 2.
| Data block | Sampled value |
| Data block 2 | ??0；-1.224；1.224；0；-1.224；1.224；0；1.224 |
| Data block 3 | ??1.224；-1.224；-1.224；0；0；-1.224；0；1.224 |
| Data block 4 | ??1.224；-1.224；0；-1.224；0；-1.224；0；0 |
Table 5
Above-described specific embodiment; purpose of the present invention, technical scheme and beneficial effect are further described; institute is understood that; the above only is specific embodiments of the invention; be not limited to the present invention; within the spirit and principles in the present invention all, any modification of being made, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (4)
1, a kind of fraction bit rate BAQ method based on the Lloyd-Max quantizer is characterized in that, this method comprises:
Sampled signal is carried out piecemeal, use the recursion mode at interblock and carry out stream treatment;
Try to achieve each partitioned sampled signal amplitude equalizing value;
The amplitude equalizing value of trying to achieve is mapped as standard deviation;
Adopt this standard deviation that partitioned sampled signal is carried out standardization;
Partitioned sampled signal after adopting the Lloyd-Max quantizer to standardization quantizes.
2, the fraction bit rate BAQ method based on the Lloyd-Max quantizer according to claim 1, it is characterized in that: there are mapping relations one by one in the amplitude equalizing value of described partitioned sampled signal and standard deviation.
3, the fraction bit rate BAQ method based on the Lloyd-Max quantizer according to claim 1, it is characterized in that: this standard deviation of described employing is carried out standardization to partitioned sampled signal, be that the standard deviation that adopts the recursion mode that the n+2 blocks of data is used the n+1 blocks of data is carried out standardization, the n+3 blocks of data is used the standard deviation of n+2 blocks of data and carried out standardization, the n+4 blocks of data is used the standard deviation of n+3 blocks of data and carried out standardization, the rest may be inferred, uses the standard deviation of 2n-1 blocks of data until the 2n blocks of data and carry out standardization.
4, the fraction bit rate BAQ method based on the Lloyd-Max quantizer according to claim 1, it is characterized in that: the partitioned sampled signal of described application Lloyd-Max quantizer after to standardization quantizes, be different from traditional Lloyd-Max quantizer with an integral number power quantization level of 2 as quantizer, but with the Lloyd-Max quantizer of several quantization levels naturally as quantizer, making bit rate is fraction bit rate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200810117048A CN101634702A (en) | 2008-07-23 | 2008-07-23 | Fraction bit rate BAQ method based on Lloyd-Max quantizer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN200810117048A CN101634702A (en) | 2008-07-23 | 2008-07-23 | Fraction bit rate BAQ method based on Lloyd-Max quantizer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101634702A true CN101634702A (en) | 2010-01-27 |
Family
ID=41593951
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200810117048A Pending CN101634702A (en) | 2008-07-23 | 2008-07-23 | Fraction bit rate BAQ method based on Lloyd-Max quantizer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101634702A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013007185A1 (en) * | 2011-07-14 | 2013-01-17 | 电信科学技术研究院 | Data compression method and device |
| CN107749994A (en) * | 2017-09-26 | 2018-03-02 | 中国科学院电子学研究所 | Deep space Coherent Noise in GPR Record compression method based on inter prediction |
| CN108646302A (en) * | 2018-03-23 | 2018-10-12 | 西安电子科技大学 | A kind of SAR data compression method for underground structure detection |
-
2008
- 2008-07-23 CN CN200810117048A patent/CN101634702A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2013007185A1 (en) * | 2011-07-14 | 2013-01-17 | 电信科学技术研究院 | Data compression method and device |
| CN107749994A (en) * | 2017-09-26 | 2018-03-02 | 中国科学院电子学研究所 | Deep space Coherent Noise in GPR Record compression method based on inter prediction |
| CN108646302A (en) * | 2018-03-23 | 2018-10-12 | 西安电子科技大学 | A kind of SAR data compression method for underground structure detection |
| CN108646302B (en) * | 2018-03-23 | 2019-07-16 | 西安电子科技大学 | A kind of SAR data compression method for underground structure detection |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5052541B2 (en) | Method for compressing SAR data and apparatus for encoding SAR data | |
| CN101742313B (en) | Compression sensing technology-based method for distributed type information source coding | |
| KR20230062888A (en) | Method and apparatus for encoding and decoding hdr images | |
| US20090103606A1 (en) | Progressive Distributed Video Coding | |
| CN100596198C (en) | Encoding method and encoder | |
| CN102298137A (en) | Method for compressing adaptive data-rate original data of satellite-borne SAR (Synthetic Aperture Radar) | |
| CN101945286A (en) | Compression coding method, decoding decompression method, device and communication system | |
| CN101634702A (en) | Fraction bit rate BAQ method based on Lloyd-Max quantizer | |
| CN102857760B (en) | Feedback-free code rate optimization distributed video encoding and decoding method and system | |
| TW202114420A (en) | Split gain shape vector coding | |
| Chuah et al. | $\ell_ {2} $ Optimized Predictive Image Coding With $\ell_ {\infty} $ Bound | |
| CN102572426B (en) | Method and apparatus for data processing | |
| CN103152568A (en) | JPEG2000 (Joint Photographic Experts Group 2000) coding method for real time cutoff of code stream and implementation system thereof | |
| CN103974072A (en) | Frame storage method based on block compression during video decoding | |
| CN102055974B (en) | Data compressing and uncompressing method, data compressing and uncompressing device and data compressing and uncompressing system | |
| CN109495415B (en) | Digital mobile forward transmission method and link based on digital cosine transform and segmented quantization | |
| Cai et al. | Bandwidth expansion Shannon mapping for analog error-control coding | |
| CN101980464A (en) | Data coding method, decoding method, coder and decoder | |
| Keshtkarjahromi et al. | Multi-level distributed arithmetic coding with nested lattice quantization | |
| CN104113394B (en) | The compression of communication modulation signal and decompressing method | |
| CN102223533B (en) | Signal decoding and coding method and device | |
| Abou Saleh et al. | Power-constrained bandwidth-reduction source-channel mappings for fading channels | |
| US6826524B1 (en) | Sample-adaptive product quantization | |
| CN105306941A (en) | Video coding method | |
| CN105578183A (en) | Compression sensing video encoding and decoding method based on Gaussian mixture model (GMM) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Open date: 20100127 |