Unit 78: Task 3 Technical file
- 1. Task 3- Technical File Pixel And Resolution: In digital imaging, a pixel, or pel, picture element is a physical point in a raster image, or the smallest addressable element in a display device; so it is the smallest controllable element of a picture represented on the screen. The display resolution of a digital television, computer monitor or display device is the number of distinct pixels in each dimension that can be displayed.
- 2. Vector and Raster images: Vector graphics is the use of geometrical primitives such as points, lines, curves, and shapes or polygon(s), which are all based on mathematical expressions, to represent images in computer graphics. "Vector", in this context, implies more than a straight line. In computer graphics, a raster graphics image, or bitmap, is a dot matrix data structure representing a generally rectangular grid of pixels, or points of colour, viewable via a monitor, paper, or other display medium. Raster images are stored in image files with varying formats
- 3. File Formats And uses: A file format is a standard way that information is encoded for storage in a computer file. A file format specifies how bits are used to encode information in a digital storage medium. File formats may be either proprietary or free and may be either unpublished or open.
- 4. GIF - Graphics Interchange Format - Images using a fixed color palette (limited to only 256 colours - not the full spectrum of colors available to your monitor). The GIF format uses compression for smaller files and faster downloads. This format is best for images with solid colors or areas of uniform colour such as illustrations and logos. JPEG - Joint Photographic Experts Group - Used for photographic (continuous tone) images. Unlike GIF files the JPEG format can take advantage of the full spectrum of colours available to your monitor. The JPEG format also uses compression for smaller files and faster downloads. However, unlike the compression method used in GIF files, the JPEG compression is "lossy" which means it discards data in the process. Once a file is saved in JPEG format the data is permanently lost. If you want all the image data available for future use, save the image using no compression or "lossless" compression and make JPEG copies from it.
- 5. TIFF - Tagged-Image File Format - Used for bitmaps only. The TIFF format is supported by virtually all graphics applications. EPS - Encapsulated PostScript® - A file format used for both vector graphics and bitmaps. EPS files contain a PostScript description of the graphic data within them. EPS files are unique in that you can use them for vector graphics, bitmap images, type or even entire pages. BMP - The BMP file format (Windows bitmap) handles graphics files within the Microsoft Windows OS. Typically, BMP files are uncompressed, hence they are large; the advantage is their simplicity and wide acceptance in Windows programs. PNG - The PNG (Portable Network Graphics) file format was created as the free, open-source successor to GIF. The PNG file format supports truecolor (16 million colours) while GIF supports only 256 colors. The PNG file excels when the image has large, uniformly colored areas. The lossless PNG format is best suited for editing pictures, and the lossy formats, like JPG, are best for the final distribution of photographic images, because in this case JPG files are usually smaller than PNG files. The Adam7-interlacing allows an early preview, even when only a small percentage of the image data has been transmitted.
- 6. PSD- Photoshop files have default file extension as .PSD, which stands for "Photoshop Document." A PSD file stores an image with support for most imaging options available in Photoshop. These include layers with masks, colour spaces, ICC profiles, CMYK Mode (used for commercial printing), transparency, text, alpha channels and spot colours, clipping paths, and duotone settings. This is in contrast to many other file formats (e.g. .JPG or .GIF) that restrict content to provide streamlined, predictable functionality. A PSD file has a maximum height and width of 30,000 pixels, and a length limit of 2 Gigabytes.
- 7. Compression: In computer science and information theory, data compression, source coding, or bit-rate reduction involves encoding information using fewer bits than the original representation. Compression can be either be lossy or lossless. Lossless compression reduces bits by identifying and eliminating statistical redundancy. No information is lost in lossless compression. Lossy compression reduces bits by identifying marginally important information and removing it. The process of reducing the size of a data file is popularly referred to as data compression, although its formal name is source coding (coding done at the source of the data, before it is stored or transmitted).
- 8. Image capture devices: The process of using devices such as digital cameras or scanners to capture images in a digital format. The resulting files are then further processed to arrive at a final image. Optimising:
- 9. Storage and asset Management: Storage Management The administration of any or all of backup, archival, disaster recovery and hierarchical storage management (HSM) procedures within an organization Asset management, broadly defined, refers to any system that monitors and maintains things of value to an entity or group. It may apply to both tangible assets such as buildings and to intangible concepts such as intellectual property and goodwill. Asset management is a systematic process of operating, maintaining, upgrading, and disposing of assets cost-effectively. Alternative views of asset management in the engineering environment are: The practice of managing assets to achieve the greatest return (particularly useful for productive assets such as plant and equipment), and the process of monitoring and maintaining facilities systems, with the objective of providing the best possible service to users.