This document discusses image selection and editing. It defines what an image is, including two-dimensional photographs and three-dimensional statues. It describes how images can be captured optically or manually rendered. The document then discusses image editing, both traditional analog techniques like photo retouching as well as digital editing software. It explains how image size refers to resolution in pixels and megapixels. Compressed file formats like JPEG can reduce file size but also decrease image quality the more an image is compressed. The document concludes by defining resolution and pixel resolution, noting that smaller pixel sizes capture more image detail for higher resolution.

1. Image Selection
and Editing

2. Content
Image
Image Size
Image Resolution

3. What is image?
 Images may be two-dimensional, such as
a photograph, screen display, and as well as a three-dimensional,
such as a statue or hologram.
 They may be captured by optical devices – such
as cameras, mirrors, lenses, telescopes, microscopes,
etc. and natural objects and phenomena, such as
the human eye or water surfaces.

4. Image
 Any two-dimensional figure such as a map, a graph,
a pie chart, or a painting.
 In this wider sense, images can also
be rendered manually, such as by drawing, the art of
painting, carving,
 Or rendered automatically by printing or computer
graphics technology, or developed by a combination
of methods, especially in a pseudo-photograph.
 In Visual Study: Photo or picture that is taken by any
types of camera.

5. Image

6. Image editing
 Image editing encompasses the processes of
altering images, whether they are digital
photographs, traditional photochemical
photographs, or illustrations.
 Traditional analog image editing is known as photo
retouching, using tools such as an airbrush to modify
photographs, or editing illustrations with any
traditional art medium.

7. Image editing
 Graphic software programs, which can be broadly
grouped into vector graphics editors, raster graphics
editors, and 3D modelers, are the primary tools with
which a user may manipulate, enhance, and
transform images.
 Many image editing programs are also used
to render or create computer art from scratch

8. Editing
Traditionally
(Analog Image)
Editing
DSLR Camera
Graphic
Software

9. Image Size

10. Image size and resolution
• Image size refers to the resolution of the image.
• Resolution is sometimes identified by the width and
height of the image as well as the total number of
pixels in the image.
• For example, an image that is 2048 pixels wide and
1536 pixels high (2048X1536) contains (multiply)
3,145,728 pixels (or 3.1 Megapixels). You could call it a
2048X1536 or a 3.1 Megapixel image.
• As the megapixels in the pickup device in your camera
increase so does the possible maximum size image you
can produce.
• This means that a 5 megapixel camera is capable of
capturing a larger image than a 3 megapixel camera

11. Compress or uncompressed
 In addition to image size, the quality of the image
can also be manipulated
 An uncompressed image is saved in a file format that
doesn't compress the pixels in the image at all.
 Formats such as 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.

12. Compressed Image
Slightly compressed spider image Over compressed spider image

13. JPG COMPRESSION
 JPG compression analyzes images in blocks of 8X8 pixels in size
and selectively reduces the detail within each block. At higher
compression rations, the block pattern becomes more visible and
there may be noticeable loss of detail, especially when you attempt
to make prints larger than recommended.
 The subject and pattern in the image is also a factor. For example, a
picture of the blue sky can be compressed quite a bit without any
noticeable effects but a picture of a colorful bird would "pixelate"
quite quickly. Take another look at the two images at the top. The
first is somewhat compressed, about 200 pixels high (size) and the
file is only 14Kb. The image on the right is the same size but
compressed quite a bit more reducing the file size to 4Kb.
 By using JPG compression, you can keep the physical size
of the image the same and reduce the amount of disk space
required to store it but you will be sacrificing the quality of
the image.

14. Resolution
 Image resolution is the detail an image holds. The
term applies to raster digital image s, film images,
and other types of images..
 Image resolution can be measured in various ways.
Basically, resolution quantifies how close lines can be
to each other and still be visibly resolved.

15. Resolution Illustration

16. Pixel resolution
 Resolution is the capability of the sensor to observe or
measure the smallest object clearly with distinct
boundaries.
 There is a difference between the resolution and a pixel.
 A pixel is actually a unit of the digital image.
 Resolution depends upon the size of the pixel. With a
given lens setting the smaller the size of the pixel, the
higher the resolution will be and the clearer the object in
the image will be.
 Images having smaller pixel sizes might consist of more
pixels. The number of pixels correlates to the amount of
information within the image.

17. Which picture has more pixel?

18. Higher Resolution?

19. Thank you…