pdf 比较(备考资料：同等学力申硕英语阅读突破训练)

nowadays, pdf files became one of the standard formats by which a variety of documents are exchanged across the internet. pdf (portable document format) is primarily a method of debugging adopted by adobe that produces platform independent documents that can be viewed in nearly any browser. many software is used to produce it such as microsoft office, adobe acrobat, and openoffice, regardless of the programs they originate from.as an effective common means of communication, and can thought of as an alternative to word documents and emal attachments. let’s compare pdf files with word documents.
first and foremostly, pdfs is more reliable than word documents. pdf makes sure that the design, layout and typographical details remain exactly how the original creator intended after being transferred from one device to the other. the documents are the same regardless which user open them. conversely, word save the formatting together with the contents in different files and may lose data during file transmission and result in different version of same document displaying different features such as font, fonts size, images and .a worse thing is that if any files get corrupted in the microsoft word document, users will be subjected to corrupted and incomplete data totally understanding.
commonly, word files takes up more bandwidth compare with pdf's, because pdfs are often saved in a much smaller or compressed versions. for example in a document which contains 4 or 5 images, word document size will greater than the pdf. namely a converting pdf file process which only need the 1.5mb 30 pages word document will be a 630kbs 8 page pdf. besie, program like adobe acrobat provides editing features, whlie modifying features in word is still limited .
to condense, pdfs is better for those who transfer large documents on the net. unlike the vulnerability of the word costs that causes fidelity issues, pdf secure formatting (layout, type, text placement ) and makes sharing secure documents a breeze. pdf files width compatible with existing, regardless of the operating systems users using.

pdf 对比度

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contrast enhancement, also simply referred to as a contrast adjustment, is a process of increasing the relative difference between the light and dark areas of an image. the more high contrast the elements in an image present, the greater the perception and emphasis will be when viewing the image. this adjustment tool can also be used to modify a dull or hazy image making it more vivid.
contrast and luminance can be of course be controlled manually or automatically with image manipulation programs. professional image programs offer lots of powerful features an presets that help with preparing an image for digital use, and this features can include increasing the contrast. microsystems, with their extensive editing technology, can ensure a spectacular illumination wherever the camera points just by heightening this contrast even beyond the baseline object tones. contrast enhancement occurs regularly, and is typically done to ensure a particular gesture’s outstanding through an intensified color role or an interactive utilization.

pdf对比

word文档用于编写文本文件和表格，可以对它们进行编辑。要向文档中嵌入图像，视频或音频，也可能要做点额外的工作。pdf文档一般用于存储档案，因此它很受欢迎。pdf文件可以将文字和图像放到一个文件中，并且能够在任何设备上准确呈现。和doc文档相比，查看pdf文档对其他使用者来说几乎是无缝的，这给pdf文档带来了优势。
此外，在处理pdf文件时，它们很难被编辑或篡改，因此它们在法律上也是可靠的凭证。而且，即使文档中的内容十分复杂，而总尺寸仅为很小的pdf文件，由此可以减少纸张打印和存档文件的尺寸。