ZBar大图像处理加速

为了减少处理时间，可以设定更大的扫描间距，减少不必要的解码类型，去除位置记录：

zbarimg -Sdisable -Scode128.enable -Sno-position -Sx-density=0 -Sy-density=10 160220206.jpg

在ubuntu系统下，jpg格式并不比bmp格式更耗时，可能是因为bmp格式图片太大，载入耗了太多时间。

测试过程:

测试图像：2560x1920pixels

联想 IdeaPad Z470

英特尔 Core i3-2310M @ 2.10GHz 双核

2 GB ( 三星 DDR3 1333MHz )

Ubuntu 15.04

import reimport commandspicname = '1553520702.jpg'regex = re.compile(r'\d+\.?\d*\sseconds')f=open('timeresult.txt','w')cmdlist = ['zbarimg ',           'zbarimg -Sdisable -Scode128.enable ',           'zbarimg -Sno-position ',           'zbarimg -Sy-density=10 ',           'zbarimg -Sy-density=20 ',           'zbarimg -Sy-density=40 ',           'zbarimg -Sy-density=10 -Sx-density=10 ',           'zbarimg -Sy-density=10 -Sx-density=20 ',           'zbarimg -Sy-density=10 -Sx-density=40 ',           'zbarimg -Sy-density=10 -Sx-density=0 ',           'zbarimg -Sy-density=20 -Sx-density=0 ',           'zbarimg -Sy-density=40 -Sx-density=0 ',           'zbarimg -Sy-density=40 -Sx-density=0 \-Sdisable -Scode128.enable -Sno-position ',          ]for i in range(len(cmdlist)):   cmdstr = cmdlist[i] + picname   print cmdstr+':'   f.write(cmdstr+':')   for j in range(1,6):     cmdout = commands.getoutput(cmdstr)     timelist = regex.findall(cmdout)     if timelist:        timestr = timelist[0]        timestr = timestr[:len(timestr)-7]     else:        timestr = '-1'     print timestr     f.write(timestr)   print  '\n'   f.write('\n')f.close()

zbarimg 1553520702.jpg:0.63 0.61 0.59 0.62 0.6 zbarimg -Sdisable -Scode128.enable 1553520702.jpg:0.56 0.61 0.55 0.56 0.55 zbarimg -Sno-position 1553520702.jpg:0.59 0.6 0.62 0.6 0.62 zbarimg -Sy-density=10 1553520702.jpg:0.42 0.43 0.41 0.42 0.42 zbarimg -Sy-density=20 1553520702.jpg:0.42 0.4 0.41 0.41 0.4 zbarimg -Sy-density=40 1553520702.jpg:0.4 0.4 0.42 0.4 0.39 zbarimg -Sy-density=10 -Sx-density=10 1553520702.jpg:0.2 0.2 0.21 0.23 0.21 zbarimg -Sy-density=10 -Sx-density=20 1553520702.jpg:0.2 0.2 0.19 0.19 0.21 zbarimg -Sy-density=10 -Sx-density=40 1553520702.jpg:0.19 0.2 0.21 0.2 0.19 zbarimg -Sy-density=10 -Sx-density=0 1553520702.jpg:0.18 0.18 0.18 0.18 0.18 zbarimg -Sy-density=20 -Sx-density=0 1553520702.jpg:0.17 0.17 0.17 0.18 0.16 zbarimg -Sy-density=40 -Sx-density=0 1553520702.jpg:0.16 0.16 0.17 0.16 0.16 zbarimg -Sy-density=40 -Sx-density=0 -Sdisable -Scode128.enable -Sno-position 1553520702.jpg:0.16 0.16 0.16 0.16 0.17 

附manual（man zbarimg）

ZBARIMG(1)                    ZBar Barcode Reader                   ZBARIMG(1)NAME       zbarimg - scan and decode bar codes from image file(s)SYNOPSIS       zbarimg [-qv] [--quiet] [--verbose[=n]]               {-dD | --display | --nodisplay | --xml | --noxml |               -S[symbology.]config[=value] | --set [symbology.]config[=value]               | image...}       zbarimg {-h | --help | --version}DESCRIPTION       For each specified image file zbarimg scans the image for bar codes and       prints any decoded data to stdout. Images may optionally be displayed       to the screen.       The underlying library currently supports EAN-13 (including UPC and       ISBN subsets), EAN-8, Code 128, Code 39, and Interleaved 2 of 5       symbologies. The specific type of each detected symbol is printed with       the decoded data.       Note that "image" in this context refers to any format supported by       ImageMagick, including many vector formats such as PDF and PostScript.       Keep in mind that vector formats are rasterized before scanning;       manually rasterize vector images before scanning to avoid       unintentionally corrupting embedded barcode bitmaps.OPTIONS       This program follows the usual GNU command line syntax. Single letter       options may be bundled, long options start with two dashes (`-´).       -h, --help           Print a short help message describing command line options to           standard output and exit       --version           Print program version information to standard output and exit       -v, --verbose[=n]           Increase debug output level. Multiple -v options create more spew.           Alternatively specify n to set the debug level directly       -S[symbology.]config[=value], --set [symbology.]config[=value]           Set decoder configuration option config for symbology to value.           value defaults to 1 if omitted.  symbology is one of ean13, ean8,           upca, upce, isbn13, isbn10, i25, code39, code128 or the special           value *. If symbology is omitted or *, the config will be set for           all applicable symbologies. These are the currently recognized           configs. Prefix a config with "no-" to negate it. Not all configs           are appropriate for every symbology.           enable               Control decoding/reporting of a symbology. For symbologies               which are just subsets of ean13 (upca, upce, isbn13, isbn10),               this config controls whether the subsets are detected and               reported as such. These special cases are disabled by default,               all other symbologies default to enabled           disable               Antonym for enable           emit-check               Control whether check digits are included in the decoded               output. Enabled by default. This config does not apply for               code128, which never returns the check digit. It also not apply               for cases where the check digit is disabled (see add-check).               Check digits are currently not implemented for i25 or code39           add-check               Enable decode and verification of a check digit for symbologies               where it is optional: this will include code39 and i25, neither               of which implements the check digit yet           ascii               Enable escape sequences that encode the full ASCII character               set. This would apply to code39, except that it´s not               implemented either...           position               Enable collection of symbol position information. Enabled by               default. Currently, the position information is unusable, so               you can save a few cycles by disabling this.           min-length=n, max-length=n               Bound the number of decoded characters in a valid symbol. If a               decode result is outside the configured min/max range               (inclusive), it will not be reported. Set to 0 to disable the               corresponding check. This setting applies to variable-length               symbologies: i25, code39, code128 and pdf417.  min-length               defaults to 6 for i25 and 1 for code39 (per Code 39               autodiscrimination recommendation); all others default to 0           x-density=n, y-density=n               Adjust the density of the scanner passes. Lower values scan               more of the image at the cost of decreased performance. Setting               to 0 disables scanning along that axis. Defaults are both 1.       -q, --quiet           Quiet operation; only output decoded symbol data. specifically this           disables the statistics line printed (to stderr) before exiting, as           well as the warning message printed (also to stderr) when no           barcodes are found in an image       -d, --display, -D, --nodisplay           Enable/disable display of subsequent image files, until next           --display or --nodisplay is encountered. This option may appear           multiple times to enable display of specific images. Image display           is disabled by default       --xml, --noxml           Enable/disable result output using an XML format. This format wraps           the raw data from the symbol with information about the scan (such           as page indices) in an easy to parse format. The latest schema is           available from http://zbar.sourceforge.net/2008/barcode.xsd.       --raw           Enable raw symbol data output. This format prints symbol data           separated by newlines without the additional symbology type           information that is printed by defaultEXAMPLES       Scan a PNG image of a UPC bar code symbol and pass resulting data to a       script that searches for the code in a database and does something       useful with it:           zbarimg product.png | upcrpc.py       The upcrpc.py example script included in the examples/ subdirectory of       the distribution will make an XMLRPC call to a popular internet UPC       database and print the product description if found.       Scan a JPEG image containing several barcodes and display the image in       a window, also disabling recognition of Interleaved 2 of 5 codes to       prevent confusion with other symbologies or background noise:           zbarimg --display -Si25.disable label.jpg       Look in a scanned document only for Code 39, using XML output format so       the page numbers are available. To enable only Code 39, first all       symbologies are disabled, then Code 39 is re-enabled:           zbarimg --xml -Sdisable -Scode39.enable scan.tiffSEE ALSO       zbarcam(1)       http://zbar.sf.net/BUGS       See http://sf.net/tracker/?group_id=189236&atid=928515AUTHOR       Jeff Brown <[e-mail]>           Lead developerCOPYRIGHT       Copyright © 2007-2009 Jeff Brown       All Rights Reservedzbar-0.10                         2009-10-23                        ZBARIMG(1)