--- title: "Image synthesis, analysis and transmission" subject: "Multimedia System" chapter: 3 key: "semester_8/multimedia_system:image-synthesis-analysis-transmission" source: https://www.bctengineer.com/q/semester_8/multimedia_system/image-synthesis-analysis-transmission site: BCT Engineering --- # Image synthesis, analysis and transmission Multimedia System · Chapter 3: Images and Graphics - Asked in: 2071 Bhadra, 6 marks - Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_8/multimedia_system/image-synthesis-analysis-transmission - Whole chapter: https://www.bctengineer.com/md/semester_8/multimedia_system/chapter-3 ## Question Explain about image synthesis, analysis and transmission. ## Short answer Image synthesis creates images from models or data (e.g., CAD, animation). Image analysis extracts features and recognises objects (e.g., OCR, medical imaging). Image transmission sends images efficiently using compression and progressive transmission over networks. ## Answer These are three parts of computer image processing: **synthesis** creates an image, **analysis** extracts information from an image, and **transmission** moves an image from one place to another. #### Image synthesis Image synthesis is the generation of an image from non-image data, such as a mathematical description, a data set or a model. Images may be produced by: - **Dynamic synthesis:** the picture is created by a program on demand and can change with time, for example a graph of a function, a medical visualisation, a user interface or a game scene. - **Static synthesis:** a stored picture is produced once, such as a designed drawing or a rendered 3-D scene. Techniques include drawing primitives (lines, circles, polygons), 3-D modelling with lighting, shading, texture mapping and rendering. Used in computer-aided design, simulation, animation and visualisation. #### Image analysis Image analysis takes an image and finds what is in it. The aim is to get a description rather than a new picture. Stages: 1. **Pre-processing** to remove noise. 2. **Segmentation** of the image into regions and edges. 3. **Feature extraction** such as area, shape, position, colour, texture. 4. **Recognition / classification** of the objects by matching with models. Examples: OCR, fingerprint and face identification, tumour detection in X-rays, robot vision, satellite image interpretation. #### Image transmission Digital images are large (a 1024 x 768 true colour image has about 2.4 MB), so they must be compressed before sending over a network. Important ideas: - **Compression** with JPEG, GIF or PNG to reduce size. - **Progressive transmission:** a coarse low-resolution version is sent first and detail is added step by step (interlaced GIF, progressive JPEG), so the user sees the picture early. - **Error protection** and suitable protocols for reliable delivery. Used in the web, fax, telemedicine, satellite imaging and video conferencing. ```text Data/model --synthesis--> Image --analysis--> Description | transmission v Remote user ``` ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. Which matches the three parts of image processing? A. Synthesis extracts information, analysis creates images, transmission compresses B. Synthesis creates an image, analysis extracts information, transmission moves the image C. Synthesis moves images, analysis creates them, transmission extracts features D. All three create images in different ways Answer: B. Synthesis generates images from non-image data, analysis describes what is in an image, and transmission sends it elsewhere. (Key point: Roles of the three parts) 2. What distinguishes dynamic synthesis from static synthesis? A. Dynamic pictures are created on demand by a program and can change with time B. Dynamic pictures are always stored on disk C. Static synthesis can only produce text D. Dynamic synthesis uses scanned photographs Answer: A. Dynamic synthesis (graphs, UIs, game scenes) is generated by a program and changes; static synthesis produces a stored picture once. (Key point: Static vs dynamic synthesis) 3. Which is the correct sequence of image analysis stages? A. Recognition, segmentation, pre-processing, feature extraction B. Segmentation, pre-processing, recognition, feature extraction C. Feature extraction, pre-processing, segmentation, recognition D. Pre-processing, segmentation, feature extraction, recognition Answer: D. Noise is removed, the image is segmented, features (area, shape, colour) are extracted, and objects are recognised by matching with models. (Key point: Analysis stages) 4. What is progressive transmission? A. Sending the full-resolution picture line by line without compression B. Sending only the edges of the picture C. Sending a coarse low-resolution version first and adding detail step by step D. Sending the picture twice for error checking Answer: C. Interlaced GIF and progressive JPEG show a rough picture early, which then improves as more detail arrives. (Key point: Progressive transmission) ## Related in other subjects - [CTFS analysis and synthesis equations](https://www.bctengineer.com/question.md?key=semester_4%2Fsignals_and_systems%3Actfs-analysis-synthesis-equations) — Signals and Systems, chapter 2 - [Significance of transmission voltage level, 132 vs 400 kV](https://www.bctengineer.com/question.md?key=semester_4%2Fpower_system_analysis_i%3Avoltage-level-132kv-vs-400kv) — Power System Analysis I, chapter 1 - [Advantages and limitations of DC transmission](https://www.bctengineer.com/question.md?key=semester_4%2Fpower_system_analysis_i%3Adc-transmission-advantages-limitations) — Power System Analysis I, chapter 1 - [Skin effect in transmission lines](https://www.bctengineer.com/question.md?key=semester_4%2Fpower_system_analysis_i%3Askin-effect-brief) — Power System Analysis I, chapter 4