Recovering Graphics Files Flashcards
The two major forms of steganography are insertion and substitution.
True
How may computer programs can be registered under copyright laws?
As literary works
What kind of images are based on mathematical instructions that define lines, curves, text, ovals, and other geometric shapes?
Vector Graphics
Which JFIF format has a hexadecimal value of FFD8 FFE0 in the first four bytes?
JPEG
Which term refers to a data-hiding technique that uses host files to cover the contents of a secret message?
Steganography
What type of laws should computer investigators be especially aware of when working with image files in order to avoid infringement violations?
Copyright
Which type of compression compresses data permanently by discarding bits of information in the file?
Lossy
What technique has been used to protect copyrighted material by inserting digital watermarks into a file?
Steganography
Which images store graphics information as grids of pixels?
Bitmap
Which data-hiding technique replaces bits of the host file with other bits of data?
Substitution
What is the process of converting raw picture data to another format called?
Demosaicing
What is another term for steganalysis tools?
Steg tools
A graphics program creates and saves one of three types of image files: bitmap, vector, or XIF.
False
Bitmap images are collections of dots, or pixels, in a grid format that form a graphic.
True
Under copyright laws, maps and architectural plans may be registered as pictorial, graphic, and sculptural works/
True
If a graphics file cannot be opened in an image viewer, what should the next step be?
Examining the file’s header data
Operating systems do not have tools for recovering image files
False
If a graphics file is fragmented across areas on a disk, you must recover all the fragments before re-creating the file
True
All TIF files start at position zero (offset 0 is the first byte of a file) with hexadecimal 49 49 3B
False
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
What is the simplest way to access a file header?
Use a hexadecimal editor
From which file format is the image format XIF derived?
TIF
What tools are used to create, modify, and save bitmap, vector, and metafile graphics?
Graphics editors
The Internet is the best source for learning more about file formats and their extensions.
True
In which format are most digital photographs stored?
EXIF
A JPEG file is an example of a vector graphic.
False
Digital pictures use data compression to accomplish which of the following goals?
Save space on a hard drive
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 sizes
Multiple copies of a graphics file
Graphics files stored on a computer can’t be recovered after they are deleted
False
In JPEG files, what’s the starting offset position for the JFIF label?
Offset 6
When investigating graphics files, you should convert them into one standard format
False
Each type of graphics file has a unique header containing information that distinguishes it from other types of graphics files
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
Copyright laws don’t apply to Web sites
False
Which of the following is true about JEPG and TIF files?
They have different values for the first 2 bytes of their file headers
What type of compression uses an algorithm that allows viewing the graphics file without losing any portion of the data?
Lossless
A JPEG file uses which type of compression?
Lossy
The process of converting raw images to another format is called which of the following?
Demosaicing
When viewing a file header, you need to include hexadecimal information to view the file
True
Only one file format can compress graphics files
False
When you carve a graphics file, recovering the image depends on which of the following skills?
Recognizing the pattern of the file header content
What methods are used for digital watermarking?
Invisible modification of the LSBs in the file
Bitmap (.bmp) files use which of the following types of compression?
Lossless
What methods do steganography programs use to hide data in graphics files?
Either of the above
