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Image File Formats - LegalScans


For an imaged electronic document to be admissible in a court of law, it must be created in a file format that cannot be altered without leaving an electronic footprint. To satisfy this requirement, the imaging industry has diverged in two different directions:

PDF File Format: A PDF file is a "read only" document that cannot be altered without leaving an electronic footprint, and meets all legal requirements to be admissible in a court of law. Furthermore, the PDF file format is practical and economical by allowing the documents to be stored on a company's server. This eliminates the need for additional hardware (except for additional hard drive space) and allows for exceptional integration into any network. <More>

TIFF, JPEG, GIF File Format: Because these file formats can be easily altered without leaving an electronic footprint, it is necessary to copy them at the time of scanning directly to an optical drive or read-only drive. Documents on an optical drive cannot be removed or changed, making them legal in a court of law. However, optical drive systems have considerable expenses attached to them as a result of the need for optical drive - scanning integration. In addition, optical drives bare hefty hardware price-tags and significant network integration expenses. <More>

File Format Specification Comparison:

Portable Document Format (PDF)

The PDF format was originally developed by Adobe for the U.S. Federal Government to store its legacy files. Currently, the U.S. Federal Government is still the largest user of PDF technology. Most individuals have encountered the PDF format when downloading electronic tax forms from the IRS.

PDF format has been a de facto Internet standard. It guarantees that the image seen by the viewer is congruent across all platforms. While PDF requires a viewer, it is readily available as freeware called Adobe Acrobat Reader.

PDF files have metadata, such as XML tables of content and links, making images more useful to end users. PDF files support security privileges, watermarking and signing, resulting in tools that exist to protect intellectual capital. Also, PDF files can be streamed by page, providing the responsiveness that browser users expect.

One significant attribute of PDF format is the superior appearance of the printed copy when reproduced using a high quality printer. Image and text characteristics of PDF files tend to reproduce very well under most display and output configurations. <More>

PDF File Types:

An image bitmap representation of the actual document. The image’s full-text is not searchable but indexes can be added during the PDF conversion process.

PDF SEARCHABLE IMAGE (also called Image + Hidden Text)
Is a combination of a bitmap image in the PDF format with embedded text within the document. The full text of this document is searchable. Files in this format have the greatest file size compared to PDF Image Only and PDF Formatted Text and Graphics.

This is a completely searchable file created from a Postscript file or editor. PDF conversion is generally done from a printing file or ML file. Of the three PDF types, PDF Formatted Text and Graphics generates the smallest file size and yields the greatest printable and viewable quality.

The main advantages Adobe claims for PDF is its portability. It doesn’t matter what operating system you have or what type of hardware you have. PDF files are becoming more and more popular because PDF’s are easily accessable across multiple platforms (PC, MAC, UNIX, LINUX). PDF provides strong copyright protection, web ready and looks exactly like the originals. PDF documents can be secured to prevent alterations, printing, or any type of annotation.

Tagged Image File Format (TIFF)

Virtually every imaging system uses the Tagged Image File Format (TIFF) with CCITT Group 4 compression for image storage.

By utilizing TIFF's strengths, such as tiling and banding, image vendors have been able to accommodate a wide range of application needs.

TIFF images tend to be much larger that most other image formats, making TIFF a poor choice for batch-mode forms being processed over the Internet.

TIFF format requires compatible viewers to be installed at every workstation for display and output requirements. Many PCs are prepackaged with basic TIFF viewer utilities, but these often are not sufficient as proprietary annotations are not generally supported. TIFF is not easily streamed over the Internet, requiring the entire file to be received before viewing. As a result, the end user must employ a broadband connection for efficient viewing. <More>

So....which one....PDF or TIF ?

Other Image File Types:

Joint Photographic Experts Group (JPEG)

For storing and displaying color or grayscale photographic material, there is no better format than JPEG. While a comparable density in JPEG format is much larger than a comparable TIFF, adequate viewing can be achieved at a lower density. JPEG files will begin displaying segments of a recognizable image as it streams, without requiring the entire file to be transmitted. JPEG also supports watermarks and digital signatures. <More>

Graphics Interchange Format (GIF)

GIF format has evolved into a commonly used format for bitmap graphics on the Internet. Browsers often display GIFs using their native code; however, they are not suited for business document imaging. The special features, such as animation, are not of value in a business setting. In addition, the poor compression of the GIF format makes it less appealing to businesses in comparison to other formats. <More>

So....which one....PDF or TIF ?