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					                       Creative Commons
       Attribution – Non Commercial – Share Alike 1.0
                                                                  Some Rights Reserved – 2004:

                                                                  Juan Carlos De Martin - juancarlos.demartin@polito.it
                                                                  Giampaolo Mancini – giampaolo.mancini@polito.it
                                                                  Marco Penno - marco.penno@polito.it
                                                                  Davide Quaglia - davide.quaglia@polito.it
                                                                  Francesco Varano - francesco.varano@polito.it
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                                                                            Internet Media Group
                                                                                                                           1
                                                                       Politecnico di Torino/IEIIT-CNR
                                                     IEIIT-CNR
   Internet



        The Open
  Media Group




 Media Streaming Project
G. Mancini, M. Penno, F. Ridolfo, F. Varano
                J. C. De Martin, D. Quaglia, A. R. Meo
                     Overview

✔ Introduction
✔ Streaming: challenges and our focus

✔ The Open Media Streaming Project
    
        Fenice, aka the OMS Streaming Server
    
        NeMeSi, aka the OMS Streaming Client
    
        Palinsesto, aka the OMS Web Broadcasting
        Manager
    
        CCOMS: the Creative Commons OMS




                                     Internet Media Group
                                                                  3
                                Politecnico di Torino/IEIIT-CNR
              About us

The Internet Media Group:
A joint research group between
 Politecnico di Torino and IEIIT-CNR
http://media.polito.it


Staff:
✔ 3 senior researchers

✔ 4 post-docs

✔ 3 doctoral students

✔ 7 graduate junior researchers

                              Internet Media Group
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                         Politecnico di Torino/IEIIT-CNR
   Cross-Domain Approach

       Image                                             Video
    JPEG, JPEG2000                                 MPEG-2, MPEG-4, H.264




                       Communications
                       Wireless, Packet Networks
                             QoS, Security




    Speech                                                Audio
GSM, MELP, Wide-band                                     CD, MP3, AAC




                   Assumption: “ALL-IP”
                                               Internet Media Group
                                                                            5
                                          Politecnico di Torino/IEIIT-CNR
          Mission


   “Processing and Reliable
Delivery of Multimedia Signals”




                        Internet Media Group
                                                     6
                   Politecnico di Torino/IEIIT-CNR
         Real-Time over IP

QoS Challenges:

✔ Bandwidth
✔ Packet losses

✔ Delay

✔ Jitter



           All time-varying!

                            Internet Media Group
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                       Politecnico di Torino/IEIIT-CNR
                    QoS Solutions

✔   Architectural Solutions
    
        IntServ (RSVP), DiffServ
✔   Infrastructural Solutions
    
        Overprovisioning
✔   Solutions for Best-Effort
    
        Playout Buffer
    
        Flow Control
    
        Robustness Techniques (link-level, E2E)



                                          Internet Media Group
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                                     Politecnico di Torino/IEIIT-CNR
            Robustness Techniques

✔   Redundancy
    
        Forward Error Correction
    
        Format Interleaving
✔ Retrasmissions
✔ Error Concealment
    
        Interpolation
    
        Extrapolation

                 Ideally, ADAPTIVE techniques!


                                        Internet Media Group
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                                   Politecnico di Torino/IEIIT-CNR
          Rate-Adaptive TX
Key idea: sometimes it is better to transmit
 at a lower rate (i.e. lower source quality) with
 less packet losses, than higher rate with
 more losses (see, e.g., GSM-AMR).

✔ Adaptive to network state
✔ Network-driven VBR codecs

✔ Feedback to server

✔ Rate choice algorithm




                                 Internet Media Group
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                            Politecnico di Torino/IEIIT-CNR
            Streaming Architecture

✔   Server
    
        Connections management
    
        Capabilities negotiation
    
        Packetization
    
        Network monitoring
✔   Client
    
        Decoding and playout
    
        Feedback to server
    
        Capabilities negotiation


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                                   Politecnico di Torino/IEIIT-CNR
                    Open Streaming
✔   Three levels of freedom/openess:

    
        Free software
    
        Open multimedia standards:
           Compression algorithms and formats
           Transmission protocols
    
        Free from software patents:
           Patented formats
           Patented algorithms



                                           Internet Media Group
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                                      Politecnico di Torino/IEIIT-CNR
          Open Streaming
       Internet Streaming Media Alliance



✔ “Our goal is to accelerate the adoption
  of open standards for streaming rich
  media - video, audio, and associated
  data - over the Internet” (www.isma.it)
✔ Protocolli IETF + Codifica MPEG-4




                                 Internet Media Group
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                            Politecnico di Torino/IEIIT-CNR
                   Open Protocols
                Internet Engineering Task Force

✔ Protocols for streaming over IP
✔ Real-Time Streaming Protocol (RTSP)
    
        Access to remote content
    
        Session management
✔   Real-time Transport Protocol (RTP)
    
        Support for Real-time multimedia transport
✔   RTP Control Protocol (RTCP)
    
        Feedback



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                                    Politecnico di Torino/IEIIT-CNR
                   Open Formats

✔   ISO MPEG
    
        MPEG-1, MPEG-2, MPEG-4
    
        MP3, DVD, DivX
✔   ITU-T H.xxx
    
        H.323, H.263, H.264
    
        Microsoft NetMeeting, GnomeMeeting
✔   3GPP/ETSI
    
        GSM
✔   Xiph.org Foundation
    
        OGG-Vorbis, OGG-Tarkin, Theora
                                       Internet Media Group
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                                  Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project




                      Internet Media Group
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                 Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project

 ✔   A reference project to create:
     
         An experimental platform to study streaming over IP
     
         A working prototype of advanced techniques
     
         A streaming suite for the community at large

 ✔   Free software development:
     
         Open Media Server/Fenice 1.4
     
         Network Media Streamer I – NeMeSI 0.3.0
     
         Palinsesto
     
         CCOMS – Creative Commons OMS

                                           Internet Media Group
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                                      Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                               Risorse

 ✔   Web Site
     
         http://streaming.polito.it
 ✔   Mailing lists
     
         omsp-developers@gemelli.polito.it
     
         omsp-bugsreport@gemelli.polito.it
     
         omsp-announce@gemelli.polito.it
 ✔   CVS/Subversion
     
         https://gemelli.polito.it/svn/{nemesi-dev,mess}
     
         https://gemelli.polito.it/viewsvn


                                              Internet Media Group
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                                         Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project

 Main features:

 ✔ Full compliance with IETF protocols
 ✔ Open multimedia codecs

 ✔ Advanced streaming techniques

 ✔ Strong ties to research

 ✔ Metadata management




                              Internet Media Group
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                         Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
        Open Media Server/Fenice




                             Internet Media Group
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                        Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                      Fenice – Introduction

 ✔ Free Software (GPL)
 ✔ Developers
     
         E. Menegatti, S. Cau, G. Emma
     
         G. Mancini, M. Penno, F. Ridolfo, F. Varano
 ✔ RTSP, RTP/RTCP compliant
 ✔ Advanced Techniques
     
         Dynamic coding algorithm change
     
         Process Pooling



                                           Internet Media Group
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                                      Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                       Fenice – Introduction

 ✔   Source code lines
     
         12867 lines , ANSI C
 ✔   Source code files
     
         33 source code files
 ✔   Compilation
     
         AutoTools
 ✔   CVS/Subversion
     
         https://gemelli.polito.it/svn/mess/trunk



                                             Internet Media Group
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                                        Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                      Fenice – Introduction

 ✔   Modules
     
         Rtsp (rtsp.c, messages.c)
     
         Rtp (rtp.c)
     
         Rtcp (rtcp.c)
     
         Sdp (sdp.c)
     
         Physical (phy.c)
     
         Media entry (media_entry.c)
     
         Scheduler (schedule.c, eventloop.c)




                                           Internet Media Group
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                                      Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                      Fenice – Features

 ✔   Speech/Audio Codecs
     
         MP3: MPEG-1 Layer III
     
         GSM-AMR: Adaptive Multi Rate
     
         PCM-lineare
 ✔   Video Codecs
     
         MPEG-1/2 Video ES
     
         MPEG System
     
         H.264
 ✔   Preliminary support for live streaming

                                        Internet Media Group
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                                   Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                          Fenice – Architecture

 ✔   Highly modular architecture
     
         Resource abstraction
     
         A set of interfaces
 Cross-layer
   module

                                     RTSP                                 layer 3
               SD        RTP      RTCP   SDP   Adaptive Rate Module       layer 2

                                  UDP/TCP/IP                              Layer 1



                    Media Entry



                                                    Internet Media Group
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                                               Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                       Fenice – Robustness

 ✔   Classical approach: fork at each
     connection
     
         Best robustness to crashes
     
         Overhead
 ✔   Fenice: fork after N connections
     
         Robustness
     
         Scalability
     
         Performance




                                           Internet Media Group
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                                      Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                      Fenice – Robustness

 ✔   Network listened to by a process at a time
     Before forking                             After forking


                                    Processo A
         Processo A                                          Processo B




     1   2   3   4              1   2     3    4    5           6   7




                                             Internet Media Group
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                                        Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                  Fenice – Access to resources

 ✔   Access to a multimedia resource
     
         Trasparency w.r.t. format
 ✔ Capabilities negotiation
 ✔ Adaptivity
     
         Network state
     
         Transport quality
     
         Link type (wired, wireless)
 ✔   SD File
     
         Source Description file


                                            Internet Media Group
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                                       Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                      Fenice – Source Description

 ✔   Resource description
     
         Format
     
         Bitrate
     
         Live, file
 ✔   Caratteristiche delle sorgenti
     
         RTP payload type
     
         Packetization choices
     
         Dynamic coding algorithm change




                                             Internet Media Group
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                                        Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
               Fenice – Source Description



stream                        stream
 default_presentation          file_name BlackHoleSun.gsm-flo
 file_name BlackHoleSun.mp3    payload_type 108
 payload_type 96               clock_rate 8000
 clock_rate 90000              audio_channels 2
 audio_channels 2              encoding_name GSM
 encoding_name MP3             sample_rate 8000
 sample_rate 44100             coding_type frame
 coding_type frame             frame_len 0
 frame_len 1152                pkt_len 20
stream_end                    stream_end


                                        Internet Media Group
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                                   Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                     Fenice – Media Entry

 ✔   The Media Entry role:


      RTSP Session                                Media Entry


                        RTP Session               Media Entry


      RTSP Session                                Media Entry


                        RTP Session               Media Entry




                                           Internet Media Group
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                                      Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
           Fenice – Dynamic coding algorithm change

 ✔ The frame overlapping problem
 ✔ Possible solutions:
     
         Use current frame (go back in time)
     
         Use next frame (jump ahead in time)
     
         Use nearest frame (optimal)

 GSM-AMR             20




           0    20        40   60   80   80   100   120   140   160   180   200   220   time (ms)


          MP3        26.1




                                                                Internet Media Group
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                                                           Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                            Fenice 1.5

 ✔   Redefinition of the distribution tree
     
         One function, one file
     
         Code modularization (division into libraries)
 ✔ Compatibility with RealOne & RealPlayer
 ✔ Multicast Support

 ✔ Palinsesto
     
         Web-based interface
     
         Define start time of streaming
     
         Soon to be released


                                              Internet Media Group
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                                         Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                             Fenice 1.5

 ✔   Multifunctional Parser XML
     
         Description of the multicast sessions
     
         It replaces the SD “language”
 ✔ Bugs and improvements
 ✔ Command Environment
     
         Remote server management
 ✔   CVS/Subversion
     
         https://gemelli.polito.it/svn/fenice/trunk



                                               Internet Media Group
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                                          Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
        Network Media Streamer I




                             Internet Media Group
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                        Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                    NeMeSI – Introduzione

 ✔ Free Software (GPL)
 ✔ Developers
     
         Giampaolo Mancini, Francesco Varano
     
         Marco Penno
 ✔ RTSP, RTP/RTCP fully compliant
 ✔ Graphical Interface

 ✔ Advanced techniques
     
         Dynamic coding algorithm change
     
         System playout buffer

                                         Internet Media Group
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                                    Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                       NeMeSI – Information

 ✔   Source code lines
     
         47510 lines of ANSI C
 ✔   Source code files
     
         230 source files (one file per function)
 ✔   Compilation
     
         Autotools, Makefile
     
         Dependencies: LibSDL, LibAVCodec, LibTool
 ✔   CVS/Subversion
     
         https://gemelli.polito.it/svn/nemesi-dev/trunk


                                             Internet Media Group
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                                        Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                       NeMeSI – Features

 ✔   Multithreading
     
         A directory per thread
 ✔ Plug-ins
 ✔ LibAVCodec-based decoding
     
         Large number of formats supported
     
         Excellent performance
 ✔   LibSDL-based multimedia output
     
         Simple Direct Layer



                                         Internet Media Group
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                                    Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                     NeMeSI – Architecture

 ✔   Execution Threads
     
         User Interface
     
         Session management (RTSP)
     
         Data reception (RTP)
     
         Flow control (RTCP)
     
         Decoding
     
         SDL presentation:
            Audio
            Video




                                          Internet Media Group
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                                     Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                 NeMeSI – Network Playout Buffer

 ✔ Helps to de-jitter
 ✔ Packet reordering
     
         Out-of-sequence packets
     
         Packets are good if they arrive before playout instant




                                            Internet Media Group
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                                       Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
          NeMeSI – Dynamic Coding Algorithm Change

 ✔   Change possible on packet-by-packet
     basis
     
         Payload Type in RTP header
 ✔   Array of pointers to function
                                      RTP packet
     
         Plug-in         MP3
                                        Header
                                                      Payload Type



                        GSM              Data


                         PCM


                         AAC



                                           Internet Media Group
                                                                        41
                                      Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                      NeMeSI – Performance

 ✔   Real-time constraints
     
         Packets arrive every few ms (e.g. 20 ms)
 ✔   Dynamic memory allocation is too heavy
     
         To every malloc(), a system call travels the kernel
 ✔   Overhead
     
         Large amount of allocations for small quantities of data
 ✔   Delay



                                           Internet Media Group
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                                      Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                 NeMeSI – Memory management

 ✔   Static memory management
     
         No dynamic allocation
     
         Very fast
 ✔   Buffer pool
     
         Pre-allocated memory pool
     
         API for management of slots
 ✔   ADUs are never copied at user level
        One copy upon reception(read() from socket)
        One copy for playout (write() to output)


                                            Internet Media Group
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                                       Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                 NeMeSI – Real-time Processing

 ✔ Real-time decoding
 ✔ Temporal granularities
     
         Time-slice of the kernel scheduler: 10ms
     
         Time-slice RTP: 20ms (e.g.)
 ✔   System Timer is not precise
        select()
     
         Imprecision grows when CPU is loaded
 ✔   Small Data Queues


                                           Internet Media Group
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                                      Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                 NeMeSI – System Playput Buffer

 ✔   The Host is “general purpose”
     
         Multitasking/multithreading operating system
     
         Non real-time scheduler
 ✔ To tolerate CPU load variations
 ✔ Possible implementations
     
         Scheduler within the application
     
         Buffer in the audio/video board
     
         Decoded data queue (small dimension)



                                          Internet Media Group
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                                     Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                   NeMeSI – Internal Scheduler


 ✔   Timestamp Scheduling
     
         Scheduling based on the RTP timestamps
     
         Implicit recovery of the delays
 ✔   Fast Cycles Scheduling
     
         No “busy waiting” cycles
     
         Delay recovery
     
         Feedback to the system playout buffer




                                          Internet Media Group
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                                     Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                        NeMeSI – Plugin

 ✔   Audio:
     
         MP3: VBR CD-quality (44.1KHz, 16 bit, stereo)
     
         GSM-AMR: VBR speech coder (8Khz, 16 bit, mono)
     
         PCM-lineare: CBR speech coding
 ✔   Video:
     
         MPEG-1 Video




                                         Internet Media Group
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                                    Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                     NeMeSI – libavcodec

 ✔   All the libavcodec codecs:
     
         MPEG-1/2, MPEG-4, H.26x
     
         Windows Media Video, Real Video, Sorenson
     
         AC3, AAC, Ogg Vorbis
     
         ...




                                         Internet Media Group
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                                    Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                      NeMeSI – API Plugin

 ✔   Primitive (API)
        int decode(data, data_len, context);
        int get_plugin_pt(void);
 ✔ Standard output format
 ✔ To add a plugin:
     
         Source code within the NeMeSI source tree
     
         Pre-compiled external dynamic library




                                          Internet Media Group
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                                     Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                         Work In Progress - Server

 ✔ A/V Synchronization
    Rethinking and optimization of the
     


    scheduler
 ✔ Increase connections scalability

 ✔ Server reengineering [ng]
     
         Access point to multimedia resources
            Network Front-end
     
         Byte flow vs. Packet flow
            Generator of real-time ready packets



                                                   Internet Media Group
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                                              Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                    Work In Progress - Server

 ✔   Streaming-adapted file format [ng]
     
         We want the server to ignore the data format
 ✔   Link-adapted forwarding scheduler [ng]
     
         Flexible, easy support of a vast range of advanced
         transmission techniques (e.g. ARQ, FEC, etc.)
 ✔   Capabilities negotiation [ng]
     
         MPEG-7/21
 ✔   Vision
     
         Streaming Tree
     
         HyperMedia Markup Language
                                            Internet Media Group
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                                       Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                 Work In Progress - Client/Server

 ✔   Metadata support
     
         Starting with Creative Commons Public License
 ✔   Intuitive User Interface
     
         MPEG-4
     
         Direct access to chapters, scenes
     
         Multilingual support
     
         Subtitles




                                           Internet Media Group
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                                      Politecnico di Torino/IEIIT-CNR
PALINSESTO


           Internet Media Group
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      Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                           Palinsesto

 ✔   Web Based Interface
     
         To program multimedia multicast sessions
     
         User-friendly multimedia coding
     
         Multiusers with varying privileges




                                             Internet Media Group
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                                        Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                 Palinsesto

 ✔   User Management




                                   Internet Media Group
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                              Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                  Palinsesto

 ✔   Upload and coding




                                    Internet Media Group
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                               Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                   Palinsesto

 ✔   Programming of multicast sessions




                                 Internet Media Group
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                            Politecnico di Torino/IEIIT-CNR
The Open Media Streaming Project
                    Work In Progress - Producer

 ✔   Creation of streaming-adapted files
     
         Off-line
     
         Live
 ✔ Array of producers?
 ✔ Vision:
        $ producer < /dev/video0 > /dev/streamer0




                                           Internet Media Group
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                                      Politecnico di Torino/IEIIT-CNR
  CCOMS
Creative Commons OMS




                  Internet Media Group
                                               59
             Politecnico di Torino/IEIIT-CNR
                                               IEIIT-CNR
Internet Media Group




Motorola, 9 June 2004   Internet Media Group               60
                                                               IEIIT-CNR
Internet Media Group




          Common(s) Themes:


                        Building a layer of reasonable copyright




Motorola, 9 June 2004              Internet Media Group                    61
                                                     IEIIT-CNR
Internet Media Group




          Projects:


                        Creative Commons Licenses
                          International Commons
                             Science Commons
                                 Metadata
                           Technical Challenges
                            Founders’ Copyright
                           Creative Experiments




Motorola, 9 June 2004         Internet Media Group               62
                                                IEIIT-CNR
Internet Media Group




          Licenses:


                            Attribution

                        No Commercial Use

                        No Derivative Works

                             Share Alike


Motorola, 9 June 2004    Internet Media Group               63
                                                          IEIIT-CNR
Internet Media Group




          Three Expressions:


                       Human-Readable: Commons Deed

                       Lawyer-Readable: Legal Code

                       Machine-Readable: Metadata




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Internet Media Group




Metadata


                       What it does --> Expression, Description, Search
                            Tools:
                                  Resource Description Framework (RDF)
                                  Extensible Metadata Platform (XMP)

                       What it does not do --> DRM




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Internet Media Group




          iCommons




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Internet Media Group




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Internet Media Group




          iCommons




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Internet Media Group




          iCommons Italia

                       Affiliate Institutions
                        Dipartimento di Scienze Giuridiche, Universita' di Torino
                        IEIIT-CNR, Torino

                       Project Lead
                         Prof. Marco Ricolfi




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    Creative Commons

Server side:
● support for licensing metadata

● send metadata using DESCRIBE

●


Client side:
● interpret licensing metadata

● take appropriate action




                        Internet Media Group
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                   Politecnico di Torino/IEIIT-CNR
Creative Commons OMS




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            Politecnico di Torino/IEIIT-CNR
Creative Commons OMS




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            Politecnico di Torino/IEIIT-CNR
  FINE




Thank you!




              Internet Media Group
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         Politecnico di Torino/IEIIT-CNR

				
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