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Learn about CMS workflows in e-commerce, corporate settings, & marketing. Explore essence principles & media formats in content management. Discover roles, technologies, and strategies in various industries.
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Professional Content Management Systems2nd Lecture: Content Related Workflow (cont.) and Essence PrinciplesDr. Andreas MautheSCC – Lancaster University
Content Related Workflows Content is managed and uses by humans. Thus, a CMS‘s first and foremost task is it to support the interaction between the user, system and content
Who is Dealing with Content? • Content access and production • Artists & craftsmen • Content accessin documentation and cataloguing • Feed assistants, Cataloguers & archivists • Search & retireval • Skill vs. Unskilled • Content related administrative tasks • Financial planning & accounting, production & programme planning, legal department
Workflows in E-Commerce Systems • Types of E-Commerce Systems • Business-to-Business • Higher qualtiy, bandwidth and storage requirements • Business-to-Consumer • More interaction and load • Basic Structure • CMS Backend • Content handling and administration • Content related workflows • E-Commerce Front-End • Customer interaction • Special offers • Search and browse support • Commercial transactions • Ordering, accounting and billing
Clients E-Commerce Front-End Web-Access CMS Backend Delivery Rights Department Registration Content Acquisition Agency Feeds RawMaterial Media Management Access Search Engine Content Management Selcted Items Metedata/ Proxies Query Fullfillment Request Rights Clearance/ Delivery Play out eCommerceSystem Cart IPR Management Logging Cataloguing Order Content Preparation Rights Clearance BackOffice Usage Accounting ERP System Billing Workflows in E-Commerce Systems
CMS in Corporate Organisations • Organisations • Large corporate • Consumer goods, automotive, etc. • Educational • Universities, higher eduction, schools • Gouvermental
Content Related Workflows in Corporate Organisations • CM in Training and E-Learning • Structure • CMS backend • E-Learning front-end • Content structure • Programs guide students through the course • Presentation determined by user interaction Atomic content modules • Creation mode • Creation of material from modules • Interactive updates through annotations • Presenation mode • Synchronous vs. asynchronous
CMS in Marketing & Sales Web/ Print - TV Radio Kiosk - media • Role of CMS • In-house management • Exchange platform for • Concerned departments • External suppliers • Out-put channels systems Supplier Agencies Conten Management System Post - production Print shop Procure - Distri - Marketing Sales ment bution
Workflows in Marketing & Sales • Content Creation • Marketing campaign developed by • Marketing department • External agencies • Input from procurement, distrubtion, sales • Material production • Material gathering • Commercials, photo shoot • Creative process • Input from external partners • Process • Iterative development process • Extended user group inlater stages • Content Distribution • Different media for different channels • Various transfer means • Web & kiosk systems • Interactive mode • Own CMS like backend
Essence Principles • Essence is the physical representation of content in different forms and formats. It carries the actual message or meaning. Essence can be produced, altered, stored, exchanged, transmitted or broadcast. • Essence in the Context of CMS • Different forms & formats • Media types • Various encoding formats • Hi-res vs. Browse • Enhanced essence processing CMS has to be format agnostic but nevertheless support advanced content processing • Additional literature for Essence Principles • W. Effelsberg, R. Steinmetz: “Video Compression Techniques” dpunktVerlag, Heidelberg, 1998
Forms of Essence • Basic Elements • Classified according to timing characteristics • Continuous • Consecutive,time dependent information units • Related to presentation time (i.e. 25 F/sec PAL 29.97 F/sec NTSC) • Video, audio, animation, etc. • Discrete • No inherent timing requirements • Text, images, graphics, etc. • Input from procurement, distrubtion, sales • Structured Essence Formats • Combining different elements • Basic & structured • Relationships through • Links • Timing constrains • Management requires • Maintenance of object integraty • Relationship consitency • Handling of external links
Media Formats & Quality Levels: Video * 100,000 represent a medium size archive
High-Resolution and Browse Formats • High vs. Low-resolution Formats • Resource requirements • Storage • Bandwidth • HiRes formats to support production & boradcasting • LowRes formats have to support the CMS workflow • Clone of HiRes format • Browsing Interchange Format (BIF) • EBU & SMPTE Request for Technology • Characteristics of suitable browse format • Basic feature set • Video • Frame & time-code accurate • Colour representation • Dual channel audio • Content related metadata • Material related metadata • Should support • Streaming and file transfer • PAL and NTSC • Quater SIF • Remote content browsing (ideally using scaleable encoding schemes)
Sampling Heights Encoding & Compression Basics Encoding: From Analog to Digital • Transformation from a Continuous to a Binary Representation Space • Information loss through approximation • Quality depending on • Sampling rate (rate at which analog value is sampled) • Quantisation (number of bits to represent a sampling value) • Video Standard: ITUT-R BT 601-5 Time
A A A B B C D D D D D E Original Data A A A B B C ! D 5 E Compressed Data Encoding & Compression Basics • Compression: Reduction of Bit Rate • Reduction due to: • Exploiting redundancies in bit stream • Skipping information that humans sense are not preceptiable to • Lossless compression • Decompressed data stream is identical to compressed data stream • Lossy compressions • Decompressed data stream approximation of original due to missing or approximated data • Basic compression techniques • Entropy coding (lossless, e.g. Run-Length Coding) • Source oding (lossy) • Takes properties of human senses into account • Hyprid coding
Video Encoding Basics I • Basic Elements • Picture elements (Pixels) • Smallest unit • Aspect ratio • Picture width to height • Conventionally 4/3 • NTSC: 525 lines and 700 rows • Colour • Presentation a combination of Red, Green and Blue (RGB) • Transmission (YUV) • 1 Luminance (i.e. Brightness, Y) • 2 Chrominance (i.e. colour information, UV) • Human eye more sensitive to alterations in brightness Different component bandwidths • Motion • Moving images at rate larger than 15 frames/sec. • PAL 25 Hz (frames/sec.), NTSC 29.97 Hz • Flicker free preception @ 50 Hz Half pictures with interleaved scanning line • PAL 2*25 = 50Hz; NTSC 2*29.97 = 59.94 Hz
Video Encoding Basics II • Digitisation • Basic steps • Sampling • Quantisation • Coding • Grey & colour levels sampled into MxN array of points • Quantisation interval of 256 • Coding • Composite coding • Sampling and coding of the entire analog signal • Signals are jointly transformed and digitised • Component coding • Separate coding of luminance & chrominance components • Multiplexed for transmission • Example: Component Coding ITU 601 4:2:2 • Y sampling rate 13.5 MHz, UV sampling rate 6.75 MHz 4:2:2 sampling • 8-bit quantisation • 864 sampling values/ line Y, 432 sampling values/ line U & V 216 Mb/s
Component Coding Standard I Table 3-1: Component Coding Standards
Component Coding Standards II Table 3-1: Component Coding Standards
MPEG Based Formats • Moving Pictures Experts Group (MPEG) • ISO/IEC-JTC1/SC29/WG 11 • Video Encoding Standards • MPEG-1 • MPEG-2 • MPEG-4 • Target Applications • MPEG-1: Format for digital storage technologies (e.g. CD) • MPEG-2: For high quality media produciton and TV • MPEG:4: For emerging multimedia applications
MPEG-1 • Standard Parts • MPEG-1 Video • MPEG-1 Audio • MPEG-1 Systems • Basics • MPEG-1 Bandwidth: • 1.5 Mb/s • 1.1Mb/s video • 128 Kb/s audio (stereo audio is supported) • Does not standardised the encoder • Specifies syntax and semantics of MPEG-1 bit stream
MPEG-1 Sampling, Quantisation and Coding • Sampling • YCbCr format • 4:2:0 Subsampling • Macroblocks • 16x16 Y (4* 8x8) • 8x8 for Cb and Cr • Discrete Cosine Transformation • 8x8 blocks are transfered from the two dimensional image into the frequency domain • 64 DCT coefficients for each block (1 DC, 63 AC) • DC coefficients for colour values, AC less importants • Quantisation • Mapping from real numbers to integer values • Use of different granularits per coefficient • Different quantisation steps to reflect relevance of DC and AC coefficients • Encoding • Entropy encoding
MPEG-1 Frame Types I B B • Group of Picture (GOP): • IBBPBBPBBI P • Frame Types • I Frames: • Intracoded Pictures • Encoded without reference to any other frame • P Frames • Predictive Coded Pictures • Require Information from previous I or P frames • B Frames • Di-directional Predictive Coded Pictures • Require information from preceding and subsequent I and/ or P frames • D Frames • DC Coded Pictures • For fast forward not used as refernce frames B B P I
MPEG-1 Issues • Data Rate & Quality • Data Rate • 1.5 Mb/s • Qualtiy comparable to VCR • Quality • VCR comparable • Access Patterns • GOP does not allow random access at every picture • IBBPBBPBBI ... • Access every 330 milliseconds