Module 8
What type of laws should computer investigators be especially aware of when working with image files in order to avoid infringement violations? International Forensics Civil Copyright
Copyright
The process of converting raw images to another format is called which of the following? Transmogrification Data conversion Demosaicing Transfiguring
Demosaicing
What is the process of converting raw picture data to another format called? Rastering Demosaicing Abstracting Rendering
Demosaicing
In which format are most digital photographs stored? PNG TIFF GIF EXIF
EXIF
What methods do steganography programs use to hide data in graphics files? Insertion Substitution Either of the above None of the above
Either of the above
If a graphics file cannot be opened in an image viewer, what should the next step be? Examining the file's name Examining the file's size Examining the file's header data Examining the file's extension
Examining the file's header data
A JPEG file is an example of a vector graphic. True False
False
A graphics program creates and saves one of three types of image files: bitmap, vector, or XIF. True False
False
All TIF files start at position zero (offset 0 is the first byte of a file) with hexadecimal 49 49 3B. True False
False
Copyright laws don't apply to Web sites. True False
False
Graphics files stored on a computer can't be recovered after they are deleted. True False
False
Only one file format can compress graphics files. True False
False
Operating systems do not have tools for recovering image files. True False
False
When investigating graphics files, you should convert them into one standard format. True False
False
When viewing a file header, you need to include hexadecimal information to view the image. True False
True
What is the simplest way to access a file header? Use an image editor Use a text editor Use a hexadecimal editor Use a disk editor
Use a hexadecimal editor
A JPEG file uses which type of compression? WinZip Lossy Lzip Lossless
Lossy
Which type of compression compresses data permanently by discarding bits of information in the file? Lossy Lossless Redundant Huffman
Lossy
In JPEG files, what's the starting offset position for the JFIF label? Offset 6 Offset 0 Offset 2 Offset 4
Offset 6
When you carve a graphics file, recovering the image depends on which of the following skills? Recognizing the pattern of the data content Recognizing the pattern of a corrupt file Recognizing the pattern of the file header content Recovering the image from a tape backup
Reecognizing the pattern of file header content
Digital pictures use data compression to accomplish which of the following goals? Save space on a hard drive. Provide a crisp and clear image. Eliminate redundant data. All of the above
Save space on a hard drive
What is another term for steganalysis tools? Image editors Hexadecimal editors Steg tools Image tools
Steg tools
What technique has been used to protect copyrighted material by inserting digital watermarks into a file? Compression Steganography Encryption Archiving
Steganography
Which term refers to a data-hiding technique that uses host files to cover the contents of a secret message? Steganalysis Graphie Steganography Steganos
Steganography
Which data-hiding technique replaces bits of the host file with other bits of data? Substitution Insertion Pixelation Replacement
Substitution
From which file format is the image format XIF derived? TIF BMP GIF JPEG
TIF
Some clues left on a drive that might indicate steganography include which of the following? Steganography programs in the suspect's All Programs list Graphics files with the same name but different file sizes Multiple copies of a graphics file All of the above
All of the above
How may computer programs be registered under copyright laws? As literary works As motion pictures As architectural works As audiovisual works
As literary works
Which images store graphics information as grids of pixels? Raster Metafile Bitmap Vector
Bitmap
What tools are used to create, modify, and save bitmap, vector, and metafile graphics? Image readers Graphics viewers Image viewers Graphics editors
Graphics editors
Which data-hiding technique places data from the secret file into the host file without displaying the secret data when the host file is viewed in its associated program? Insertion Substitution Pixelation Replacement
Insertion
What methods are used for digital watermarking? Implanted subroutines that link to a central Web server automatically when the watermarked file is accessed Using a hex editor to alter the image data Nothing; this is what you'd expect to see. Invisible modification of the LSBs in the file
Invisible modification of the LSBs in the file
Which JFIF format has a hexadecimal value of FFD8 FFE0 in the first four bytes? BMP JPEG EPS GIF
JPEG
Bitmap (.bmp) files use which of the following types of compression? WinZip Lossless Lzip Lossy
Lossless
What type of compression uses an algorithm that allows viewing the graphics file without losing any portion of the data? Recursive Lossless Vector quantization Lossy
Lossless
Which of the following is true about JPEG and TIF files? They differ from other graphics files because their file headers contain more bits. They differ from other graphics files because their file headers contain fewer bits. They have different values for the first 2 bytes of their file headers. They have identical values for the first 2 bytes of their file headers.
They have different values for the first 2 bytes of their file headers
Bitmap images are collections of dots, or pixels, in a grid format that form a graphic. True False
True
Each type of graphics file has a unique header containing information that distinguishes it from other types of graphics files. True False
True
If a graphics file is fragmented across areas on a disk, you must recover all the fragments before re-creating the file. True False
True
The Internet is the best source for learning more about file formats and their extensions. True False
True
The two major forms of steganography are insertion and substitution. True False
True
To identify an unknown graphics file format you need to examine a copy of the unknown file with a hexadecimal editor to find the hex code for the first several bytes of the file. True False
True
Under copyright laws, maps and architectural plans may be registered as pictorial, graphic, and sculptural works. True False
True
What kinds of images are based on mathematical instructions that define lines, curves, text, ovals, and other geometric shapes? Vector graphics Line-art images Metafile graphics Bitmap images
Vector graphics
