Use of standard file formats for graphics files

The image I have created has been saved using 3 different file formats which are GIF, PNG, and JPEG.

GIF format

The difference in output quality between the images is that the GIF file format makes the image look pixelated when zoomed in and even when zoomed out you can still see that its different from the original image.
File size – 42.3 KB

Facegif

JPEG format

JPEG uses lossy compression to compress an image, this means that it will lose some of its quality after the compression technique.
File Size – 97.9 KB

Facejpeg

PNG format
PNG on the other hand does not lose any quality when compressed but it can be made transparent and lose its backround picture. But the image or object itself remains the same as the original image. The reason for this is that PNG uses the form of Lossless Compression. PNG was created as an improved, non-patented replacement for Graphics Interchange Format , and is the most used lossless image compression format on the World Wide Web.

File Size – 9.51 KB

Facepng

Posted in Uncategorized | Leave a comment

Vector Graphics

Vector Graphics is used to create images or a picture from a selection of tools and objects. Vector graphics only stores the attributes of an object within your picture, and does not have to store each individual pixel as of Bitmapped graphics. Vector Graphics can save memory over Bitmapped Graphics as it does not need to store each individual pixel, depending on the amount of shapes which are in your Picture – the more shapes/objects you have the more memory it may take up. The drawback of Vector Graphics is if you are wanting a very detailed and realistic image Vector Graphics may not be an option as most of the images created dont look real or are mostly used for Logos such as the following:

monograms

Some Vector Graphics programs are Sumo Paint, Serif Draw Plus, and Vector Works. These Programs all have a variety of tools and objects for you to create an image, some of the tools are Circle, Square, Freedraw (Pencil) or PaintBrush, and Curv. These really help you if you are wanting to create an image or Design.

Posted in Uncategorized | Leave a comment

Audio-editing Functions

Clipping – Clipping is one form of distortion that occurs when an amplifier is overdriven, which happens when it attempts to increase voltage or current beyond its limits. When an amplifier is asked to create a signal greater than its maximum capacity, it will amplify the signal only up to its maximum capacity, at which point the signal will be amplified no further. As the signal simply “cuts” or “clips” at the maximum capacity of the amplifier, the signal is said to be “clipped.”

Stereo – This is the format of two sounds that are divided into two separate channels. The two channels are then played back simutaniously through speakers. The idea is to create a fuller sound and give the ability to mix separeate sounds between channels.

Surround sound – is a term used to describe a type of audio output in which the sound appears to “surround the listener” by 360 degrees. It is also a technique for enriching the sound reproduction quality of an audio source

Fade – This is a gradual increase or decrease in the level of an audio signal. This is also a recorded sound or song that may be gradually reduced to silence at its end – fade-out, or may gradually increase from silence at the beginning – fade-in.

Posted in Uncategorized | Leave a comment

Bitmapped Graphics – Technical Terms

Dithering – Dither is an intentionally applied form of noise used to randomize quantization error, preventing large-scale patterns such as color banding in images. Dither is routinely used in processing of both digital audio and digital video data, and is often one of the last stages of audio production to compact disc. Dithering scatters different colored pixels in an image to make it appear as though there are intermediate colors in images with a limited color palette. From what we have learnt in class dithering is when a colour gradually changes to become another full colour going through hundreds of other colours in the process e.g. From green, greenish yellow, yellow, etc until is reaches white. This could also be said for sound as well gradually changes to become another full sound temperature is one in which is a good example as well.

225px-Dithering_example_dithered_256color

Anti-aliasing – this is when one colour represented gradually changes to also become a full colour like the example given above about the colour, in which it gradually changes to become the colour of whats behind the object within that image e.g yellow object and black backround the yellow will change from yellow to greenish then to red then to darkish brown then finally to the backround colour which is black.

Increase resolution(re-sampling) – Increasing the resolution of an image will increase the images quality in which the image will become more accurate to its actual colour of which it was captured at. There are drawbacks however increasing it will also increase its file size of what it will be saved at this may take up memory as the image will need more memory to store its contents. If it takes up to much memory you can use compression in which this will decrese its file size by decresing the amount of pixels or duplicating the same colour in one pixel to another one which has a similar colour e.g. blue and cyan. Doing this will decrease its quality and you can mostly see this when you zoom in on an image in which the image can appear to have big squares or blocky, in which this is due to the compression technique.

Posted in Uncategorized | Leave a comment

The Processor

The Processor is the part of the computer which controlls everything that goes on within the computer. There are many parts which make up the processor which include the ALU – Arithmetic Logic Unit, Control Unit, Memory address register, Memory Data register and the other registers. All of these are connected by internal buses which are used to transmit Information. The ALU controls arithmetic calculations and performs mathematical, logical, and decision operations in a computer and is the final processing performed by the processor. Once the information has been processed by the ALU it is then sent to the computer memory.

From the processor to the Main memory there are Buses which are set to tranmit information to and from the processor to the Main memory in which include addess bus, Data bus, and the Control Bus and in the main memory each storage location is represented each with their own unique code in which this is called an address.

The address bus – this tranmits information which is carried from the processor to the main memory. This informs the Main Memory which location will be read or used to store data. Each wire on the bus carries one bit of information at a time. The number of wires on the bus determined the number of memory locations. Increasing the width of this bus, increases the number of memory locations that it is possible to address.

The data bus – this type of bus carries information to and from the processor and the main memory. This stores data in a memory location and reads data from a memory location. As with the address bus each wiwre on the bus carries one bit of information at a time. The description of the computer informs the user of the number of wires in a bus. Increasing the width of this bus increases the quantity of data that can be carried at one time and so increases the performance of the computer system.

The control bus – Each wire on the bus has its own seperate function and its activated seperately from other wires.

Read

Informs the memory that data is to be sent to the processor from a spercified memory location.

Write

Informs the that data is to be stored in a specified memory location

Clock

This generates a pulse which regulates the direct flow of information.

The processor can only do one thing at one time so when an action or message from a peripheral device causes the processor to stop processing the current task. Current data is stored in a temporary storage location called a stack. The processor deals with the interupt. The data is then received from the stack and the previous task is resumed

Reset – this clears all internal processor registers the computer to its initial switched on state

Posted in Uncategorized | Leave a comment

Bitmapped and Vector Graphics

    Bitmapped Graphics

Bitmapped Images are made up of pixels in a grid. Pixels are picture elements; tiny dots of individual color that make up what you see on your screen. All these tiny dots of color come together to form the images you see. Bitmap images are resolution dependent. Resolution refers to the number of pixels in an image and is usually stated as dpi (dots per inch) or ppi (pixels per inch). Graphics can also be edited to pixel level (each individual pixel can be edited).

Bit depth is a term to an amount of pixels in a given area, in which is used to represent the colour of the pixels.

Colours Bits
2 1
4 2
8 3
16 4
32 5
64 6
128 7
256 8
65536 16
16777216 24 – True Colour

True Colour is the number of colours the human eye can see

But there is some disadvantages to bitmapped graphics as the file size can be very large also the file is printed at the same resolution as it is shown on the screen. Unlike vector graphics, bit mapped graphics when soomed in causes a loss of quality.
Bitmapped images mostly come in the form of a photographic image from a camera.

    Vector Graphics

Vector Graphics store an image using geometrical objects like points, curves and polygons. Each object is saved as a set of attributes. In vector graphics it is not possible to change the colour of part of the object or delete part of the object, changing the colour can only be done as full only the whole object can change colour and you can only change or amend its shape as well and not deleting a part of the object. Vector Graphics are great for creating Logos or cartoonish objects and the file size of it can be very small depending on the amount of objects that are in it. Also the image is resolution independant and cannot lose quality at all e.g. if it is sent to a printer which has a higher resolution it will at that higher resolution

Posted in Uncategorized | 1 Comment

Data Representation

Data Representation

Positive and Negative Integers – If a number has no sign it usually means it is a positive number e.g. 4 would mean +4. If we have a number such as 56719 this could be read as
Ten Thousands 10’4 Thousands 10’3 Hundreds 10’2 Tens 10’1 Units 10’0
5 6 7 1 9

Negative Integer – The simplest way to represent a negative number in binary is to use the first bit of the number to represent whether the number is positive or negative:
011 = 3
111 = -3
This is know as a signed bit Representation. The preblem with signed bit is that zero has two values – 000 – 0 and 100 = -0
Use the first bit of the number to represent if the number is positive ir negative.

Real Numbers – In computers we represent real numbers by storing 2 seperate items of data.
The mantisa – the complete number without the point
The exponent – the number of places the point must be moved to return to its original position.
Real Numbers include whole numbers, Rational Numbers, Irrational numbers and Real numbers can also be positive, negative or zero.

Text Representation – Each character is represented using a unique binary code.
Character set – This is a list of all the characters a computer can process.
ASCII – Thisa is an Internationally agreed code which represents an american – english code.

It uses 7 bits to represent each character.
The code 0 – 31 represent control characters e.g. TAB return
They are non-printing characters.
Extended ASCII uses 8 bits 256 characters.
UNICODE – this was designed to support a range of different alphabets including arabic, chinese, japanese and bangia. By using 16 bits (2 bytes instead of 1) This means UNICODE can store 65,536.

Bitmapped Graphics – An image is made up of tiny dos which are called pixels.

Resolution – this determines the quality of the picture. The smaller the pixels the finer the detail that can be displayed on the screen. The bit depth is the number of bits used to represent the colour of the pixels is called the bit depth. The true colour is the number of colours the human eye can see its all the colours known to man that you can see or have ever saw.
The advantages of bitmapped graphics are as follows:
The file are is fixed
The graphic can be edited to pixel level
Disadvantages:
The file size is very large
The file is printed at the same resolution as it is shown on the screen
Enlarging the image causes a loss of quality

Posted in Uncategorized | 1 Comment