精品999网站,亚洲欧美激情在线视频,亚洲三级电影全部在线观看高清

名羽 — Tue, 02 Dec 2008 03:21:00 GMT

在概要设计时�Q�发现参与讨论的人对什么是模块,模块的划分根据是什么的认识有很大的差异�?br>我也不敢�׃��定论�Q�还是看看书本是怎么说的�Q?br>---------------------------------------------------
1 .参考一下《��Y件架构艺术》一书，Stephen T. Albin 在里面描�q�ͼ�

Modules are discrete units of software (binary and source). Binary modules are instantiated at run time and these instantiations are commonly called components and connectors. A given module may contain the specifications for several component types and connector types. The component (instances) may be of a fixed number in some situations. For example, a Web server executable, when launched, results in a single Web server component instance. The Web server module is the binary code that exists as a set of program files. The Web server component is a running instance of the Web server.

I have seen some confusion over the use of the terms module, component, and connector. A module is a discrete unit of design that is composed of a hidden set of elements and a set of shared elements. Modules have high internal cohesion and low external coupling. Modules may represent the physical packaging of the application's binary code, which can be described further by component types and connector types. Components and connectors describe the physical instantiation of a system. The term component is often used to mean a component type or module. A module refers to a unit of software that can be designed, implemented, and compiled into a deliverable executable system or subsystem; it is a unit of execution. A component is a runtime entity, the definition of which exists in a module. A classic modular architecture is a client-server system. The client and the server are two modules. The server exports some elements such as a set of publicly visible relational database tables and views. The client knows about this publicly visible schema. The client and server are unaware of the internal composition of the other.

那么按红色部分来��_��如果说一个dll或一个Exe里由多少个模块组成这��是的笑话了�?br>2 .参考Mary shaw的《��Y件体�pȝ��》：
    模块式��Y件被划分成独立命名的�Q��ƈ可被独立讉K��的成分。模块划分，�_�度可大可小。划分依据是对应用逻辑�l�构的理解�?/span>
�q�个定义�Q�似乎有没有《��Y件架构艺术》那么严根{��没有定义具体什么�ؓ“被独立访�?#8221;的成分�?br>3. 《Documenting_Software_Architectures�?br>   A module tends to refer first and foremost to a design-time entity. Parnas's foundational work in module design (1972) used information hiding as the criterion for allocating responsibility to a module. Information that was likely to change over the lifetime of a system, such as the choice of data structures or algorithms, was assigned to a module, which had an interface through which its facilities were accessed.
    其说�Q�模块是设计时的实体�Q�特�Ҏ��信息隐藏和能通过模块的接口访问。在介绍模块视图时他��_��
    A module is a code unit that implements a set of responsibilities. A module can be a class, a collection of classes, a layer, or any decomposition of the code unit. Every module has a collection of properties assigned to it. These properties are intended to express the important information associated with the module, as well as constraints on the module. Sample properties are responsibilities, visibility information, and author. Modules have relations to one another. Example relations are is part of or inherits from.
---------------------------------------------------

不同的作者有不同的看法，但综合一下，我认为模块因该是一个独立设计的单元�Q��ƈ为其他模块提供访问接口。也��是��_��他是一个架构中的设计元素，但不限制他的存在模式�Q�也��是他是提供了可讉K��接口而且实现某一功能的一个实体，可以是一个类或一�l�类或可执行�E�序�{��?br>

名羽 2008-12-02 11:21 发表评论

�q�度�ȝ��

名羽 — Mon, 04 Feb 2008 07:29:00 GMT

今天是年二十八，一�q�又要过��M��。明天就可以攑ց�休息了。下班前抽空做下�q�度�ȝ��。今�q�我主要集中�_�֊�在h323上，更确切的说是在OPenh323上。虽说我不算聪明�Q�但�q�一�q�的研究�q�是有点收获的，主要在以下方面：
1 对现有opneh323不支持的h.264的加入�?br> 虽然不是很按标准�Q�用的是常规视频能力来加入的�Q�但也算是在视频的清晰度上有所提高�?br>2 �Ҏ��需要自己徏立多条对应的h323逻辑通道来传送自��q��数据。逻辑通道可以是rtp也可以是TCP�?br>3 用h323协商逻辑通道的方式来建立自定义的RTP通道。现在这�U�方式用在GIPS的RTP上效果还真不错！

名羽 2008-02-04 15:29 发表评论

OPenH323要分家了

名羽 — Mon, 22 Oct 2007 01:58:00 GMT

H323�?span lang="EN-US">SIP果然难于共存�?span lang="EN-US">Openh323原有的开发者也��分��Z��大块�Q?/span>

OPAL VOIP�Q?保留Opal现有H323功能�Q�但重点明显是要向兼�?span lang="EN-US">SIP方向发展�Q�其�|�站介绍为：

OPAL implements the commonly used protocols used to send voice, video and fax data over IP networks. Originally part of the OpenH323 project, OpalVoip has grown to include SIP and IAX2.

h323plus�Q�在原有OpenH323基础上��l�完�?span lang="EN-US">ITU�?span lang="EN-US">H323�p�d��的协议，其介�l��ؓ�Q?/span>

The H.323 Plus project intends to do much more than simply provide a new home for open source H.323 developers. Developers have told us they intend to work to provide significant new enhancements to the very successful H.323 systems deployed worldwide. For example, NAT/FW traversal, instant messaging, presence, and many other enhancements are already in progress or being planned. Further, the open source community has expressed interest to us to enable more collaborative features to H.323, including such things as application sharing, whiteboarding, and other capabilities.�Q�可惜，�q�些功能OPAL��不能用��C��Q?span lang="EN-US">

至于底层�?span lang="EN-US">pwlib�Q�即ptlib�Q�估计暂时还会保持一致�?span lang="EN-US">

分家后期邮�g列表也将分开�Q?span lang="EN-US">

https://lists.sourceforge.net/lists/listinfo/opalvoip-devel

http://lists.packetizer.com/mailman/listinfo/h323plus

�|�站地址分别�Q?span lang="EN-US">

http://www.h323plus.org/

http://www.opalvoip.org/

对于我们可能会更兛_��OpenH323的主要开发�?Simon 的以下言论：

The following projects are currently planned to be supported within H323plus.

OpenMCU (including remote conference controls) OpenAM (upgraded to support VoiceMail support to GnuGk) MyPhone OhPhone

The Library is almost drop-in replacable with the existing OpenH323 and contains numerous enhancements including video plugins (compatible with

Opal) and large amount of new work not currently supported in Opal.

Some of the new work now available in h323plus H.230 Conference Controls (incl tunneling GCC (T.124))

H.239 Application Sharing

H.249 Extended user inputs

H.341 SNMP support

H.350 LDAP WhitePages

H.460 Numerous custom Extensibility features

Text Messaging (working doc ITU),

Follow Me,

PDI (Personal Data Interchange)

H.460.9 RealTime QoS Measurements

Video Plugins (fully compatible with Opal)

H.235 Plugins (for external Biometric and smartcard authenticators) QoS Capability negotiation Conference Controls capability advertisement.

New work planned/proposed

H.460.presence

H.460.18/19 Nat Traversal

Video on Demand project (using H.239/H.249)

We can also provide full consulting service support for existing openH323 based projects as well as provide assistance in migration of these projects to h323plus.

名羽 2007-10-22 09:58 发表评论

MCU多通道传送音视频

名羽 — Sat, 29 Sep 2007 00:57:00 GMT

研究h323 端点间通过多通道发送数据，例如MCU可以向EP用多通道来发送音视频。这�D�|��间我从音频上作了��试�Q�可以把多�\音频通过多个通道发送给EP让EP直接在声卡上混音�Q�效果不错。但�Q�MCU-〉EP�Q�音频��用多通道�q�只是一�U�在�|�络带宽非常好的情况下的�Ҏ��Q�因为如果用的是G.711(单�\64kbit/s)��׃��可能在带宽有限的公网上��用了�?

名羽 2007-09-29 08:57 发表评论

老温也开blog了关于x264的东西可以到他那里看�?

名羽 — Wed, 25 Jul 2007 03:32:00 GMT

http://www.cnweblog.com/realwnc/

名羽 2007-07-25 11:32 发表评论

名羽 — Mon, 23 Jul 2007 09:31:00 GMT

�׃��与OphenH323中h263使用的ffmpeg库冲�H�所以把h263也提出来另外实现.

名羽 2007-07-23 17:31 发表评论

气愤!再急也不该生��垃圾代码呀!

名羽 — Fri, 11 May 2007 02:35:00 GMT

上头头脑发热.急于让我们在原来的视频会议基��上完成数据会议T120的大部分功能.我们被避着以很多非标准的自定协议代替T120标准中规定的东西.而且新的架构的改动都没有详细分析��开始着手写代码�?也就是说我们开始生产垃�?
鄙视领导者的短浅眼光!

名羽 2007-05-11 10:35 发表评论

名羽 — Fri, 30 Mar 2007 07:02:00 GMT

目前对Openh323的源代码已有较多的了解，开始对部分协议�q�行扩展例如H245会议��理部分�Q?CIF的加入．另外现有的协议栈代码中没有实现T120通道的数字会议，目前正对该部分进行补充．

名羽 2007-03-30 15:02 发表评论