TOPIC
Unit 30- Digital Graphics
THEORY
P2 and D2
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
What Is P2?
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
What Is D2?
• For D2, learners need to use and show use
of:
•
•
•
•
different file formats
different compression techniques
different image resolutions
different colour depths
• For each show the differences between the
origional and final file sizes and discuss the
differences
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
What Where?
BTEC Level 3
Unit 30
Graphics
LEARNING
P2 Information Goes In
Client Proposal
(General Background
Information)
D2 Evidence Goes In Client
Proposal
A Mix Of Screenshots /
Written Evidence
TOPIC
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
File Handling
• What Is File Management or File Handling
• It is making sure that converted files; file
sizes; file formats eg jpg, bmp are in correct
format in your folder structure
• Always name your files properly
• Always setup folder structures that help
you find your work
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
Graphical File Conversion
• You cant just convert one type to another
• Many of these image formats are native to
one specific graphic application and are not
offered as an export option in other
software.
• Not all vector and bitmap graphics convert
/ swap file formats
• If you need to convert between other
formats, you can check into the image
converters,image editors and image
viewers
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
Different compression
techniques
• Compression can be lossy or lossless.
• Lossless compression means that as
the file size is compressed, the picture
quality remains the same - it does not
get worse. Also, the file can be
decompressed to its original quality.
• Lossy compression permanently
removes data.
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
Let’s Watch A Video
• https://www.youtube.com/watch?v
=2Qo5prktYNQ
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
File Compression
• PNG
• PNG is a lossless compression type. It is often used where
the graphic might be changed by another person or where
the image contains layers of graphics that need to be kept
separate from each other. It is high quality.
• JPEG
• JPEG is often used for digital camera images because it has
a fairly small file size for the quality that it displays. JPEG is
a lossy format that offers a higher compression rate than
PNG in the trade-off for quality.
• GIF
• GIF compresses images to a maximum 8-bit colour depth,
making it unsuitable for high-quality photographs. GIF is
often used where transparency is needed on the graphic.
GIF can also be used to store simple animated images.
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
Compressing File Sizes
Below are comparisons of the same image saved in
several popular file types.
Tiff, uncompressed 901K
Tiff, LZW lossless compression (yes, its actually
bigger) 928K
JPG, High quality 319K
JPG, medium quality 188K
JPG, moderate web quality 105K
JPG, low quality / high compression 50K
JPG, absurdly high compression 18K
PNG, lossless compression 741K
GIF, lossless compression, but only 256 colors 131K
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
File Formats, Meanings &
Compression
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
BTEC Level 3
Unit 30
Graphics
LEARNING
What Is Colour Depth?
TOPIC
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
Different image resolutions
•
Image resolution is the detail an image holds. The term applies to
raster digital images, film images, and other types of images.
• For example, an image that is 2048 pixels wide and 1536 pixels high
(2048X1536) contains (multiply) 3,145,728 pixels (or 3.1
Megapixels).
• Higher resolution means more image detail or quality.
Quality and Compression
• The quality of the image can also be manipulated.
• Here we use the word "compression". An uncompressed image is
saved in a file format that doesn't compress the pixels in the image
at all.
• BMP or TIF files do not compress the image.
• If you want to reduce the "file size" (number of megabytes required
to save the image), you can choose to store your image as a JPG file
and choose the amount of compression you want before saving the
image.
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
BTEC Level 3
Unit 30
Graphics
LEARNING
TOPIC
What Is Best Where?
BTEC Level 3
Unit 30
Graphics
LEARNING