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NCast Telepresenter Reference Manual

NCast Product Specification

Telepresenter M4

 Reference Manual

Revision 2.2

March 1st, 2010

M4 Software Release 5.2.0

M3 Series 2 Software Release 5.2.0

Copyright © NCast Corporation, 2010

NCast Corporation

 

  

                                              

 

  

                                                                          

 

 Revision 2.2

 

 

Page 1

Содержание Telepresenter M4

Страница 1: ...Manual NCast Product Specification Telepresenter M4 Reference Manual Revision 2 2 March 1st 2010 M4 Software Release 5 2 0 M3 Series 2 Software Release 5 2 0 Copyright NCast Corporation 2010 NCast Co...

Страница 2: ...6 Display Function 13 2 7 Audio Subsystem 13 2 8 Archive Disk 14 3 Configuration Settings and Parameters Reference 15 3 1 Unit Options Settings 15 3 2 Passwords 17 3 3 Web Control 18 3 4 Display Sett...

Страница 3: ...s 83 8 1 Frame Layouts and Presets 83 9 Telepresenter Interfaces 88 9 1 Serial Interface 88 9 2 Telnet Interface 88 9 3 HTTP Interface Archive Download 89 9 4 HTTP Interface Image and Thumbnail Captur...

Страница 4: ...pheral of the system FCC NOTICE This device complies with Part 15 of the FCC Rules Operation is subject to the following two conditions 1 this device may not cause harmful interference and 2 this devi...

Страница 5: ...nce with the instruction manual may cause harmful interference to radio communications Operation of this equipment in a residential area is likely to cause harmful interference in which case the user...

Страница 6: ...ace a digital interface standard which provides for connection to LCD panels and displays H 264 A compression format that delivers very high quality video at low bit rates MPEG 4 Part 10 utilizes the...

Страница 7: ...lay surface with a resolution of 1920x1200 pixels WXGA Describes an image or display surface with a resolution of 1366x768 pixels Some projectors use WXGA to refer to 1280x720 as well This display siz...

Страница 8: ...inator is the master controller for the conference and is allowed to pass control to any participant in the conference at any time When a participant receives control the participant s unit begins tra...

Страница 9: ...nected via multicast can receive the media streams For optimum performance consideration must be given to the bandwidth requirements for all senders and receivers In this mode of operation questions a...

Страница 10: ...en t using DHCP and need to enter static IP addresses edit a ntwkconf txt file onto a USB stick and plug it into a USB port See the Network Settings section for details on this file 2 When you see the...

Страница 11: ...ver RTFM There are hundreds of different configuration options for a Telepresenter allowing the setup and composition of many different formats resolutions PIP options layouts bit rates frame rates st...

Страница 12: ...s and decompress media streams to encapsulate and decapsulate outgoing and incoming packets streams to enable the web interface serial interface and telnet interface and to prepare data for display on...

Страница 13: ...stream is split into segments which are then encapsulated into RTP packets according to the protocol standards set forth in IETF RFC 3016 or RFC 3984 H 264 These packets are presented to the Ethernet...

Страница 14: ...s standard MPEG 4 mp4 which can be played on a variety of desktop client players or these same files can be installed on a video streaming server for on demand playback over the Internet An optional l...

Страница 15: ...om its peers Examples M4 West Campus M4 Engineering The Unit ID is written to the XML meta data file which accompanies each recording and may be used to index the recorded file based on information ab...

Страница 16: ...d may drift over longer time periods This option takes effect immediately If the NTP client is disabled an additional setting for manual time and date setup shows up The NTP client requires a proper D...

Страница 17: ...epresenter This password should be chosen carefully and with security in mind Avoid use of common names dictionary words and the like A randomly chosen string greater than 8 characters in length is su...

Страница 18: ...ter in open and insecure networks without the use of HTTPS presents a security risk and should be avoided The Web Control page allows three different options related to Viewer and Administrative acces...

Страница 19: ...he displayed material shows the final form composition of what will be compressed and recorded except for the audio meter if present However in the case of full duplex streaming or collaboration mode...

Страница 20: ...ers or intervening equipment 3 4 2 Display Aspect Ratio The display aspect ratio will normally be auto detected as above through the use of EDID information If not correctly detected it may be set thr...

Страница 21: ...s standard VGA output and optionally with an additional graphics card DVI output 3 5 CUSTOM SETTINGS The Custom Settings page allows users of the Telepresenter to define unique dimensions for the Fram...

Страница 22: ...er if a special composite image is desired some combination of Main PIP and Overlay windows then the user would probably have to define a custom Frame Size The two entry fields define in pixels the wi...

Страница 23: ...therwise the pixels will be non square which is common in many video systems The values entered for W H are integers in the range 1 1000 3 5 3 Custom Windows The Main and PIP input streams must be ass...

Страница 24: ...transparency to limit the amount of underlying graphical material which is blocked Images must be less than 4 MB in size The X Y entries in these fields are integers or percents The X Y offset defined...

Страница 25: ...ce See Section Error Reference source not found for details on dynamic upload 3 5 6 Custom Text Overlays Text Overlays are windows which contain text to be displayed on the frame The text can be inser...

Страница 26: ...led The DHCP setting means that any network or router which provides DHCP services will automatically assign an IP address to the unit This address is reported on the display screen during initial boo...

Страница 27: ...he Telepresenter are achieved through use of HTTP protocol If the network being used is firewalled and requires the use of HTTP Proxy services then this checkbox must be enabled for proper downloads o...

Страница 28: ...y the new one will be used This file should be created edited with any simple ASCII text editor e g Notepad Teachtext Do not use an advanced word processing editor to alter this file Each key value pa...

Страница 29: ...eld may contain www xxx yyy zzz A single address www xxx yyy An address range www xxx yyy 0 24 A subset of a network CIDR notation www xxx yyy zzz sss ttt uuu vvv A comma separated list of addresses w...

Страница 30: ...the Solution The Scheduler Implementation uses three components to allow automatic start stop scheduling of one or more Telepresenters in a network These components are An administrative interface ba...

Страница 31: ...nistrator enters one or more scheduled events for a Telepresenter 2 The scheduling process queries the calendar at regular intervals and captures these events 3 Commands sent to the IP Serial Interfac...

Страница 32: ...be listed This allows one calendar to control many different units The Calendar field must be the primary or default calendar for this account The Description field is a series of serial IP commands...

Страница 33: ...dard known as iCalendar Another situation where use of an iCalendar file would be needed is when immediate access to Google Calendar is not available For example if Telepresenters are being utilized t...

Страница 34: ...iCalendar files is to first import them into a Google Calendar account and then use the Scheduler program only with Google Calendar To import an iCalendar file into Google 1 Go to the Settings link up...

Страница 35: ...e calendar entries View iCalendar Check on activities scheduled by iCalendar entries 3 9 14 Activating the Serial Interface The IP serial interface on a Telepresenter must be enabled to receive the se...

Страница 36: ...aded or they can be error reports such as Disk full Event are categorized by their severity level Info Warning Error and Critical and by their specific action or type e g Session start Recording start...

Страница 37: ...P Port Enter the port number needed to contact your SMTP outbound server Normally port 25 the port number might be non standard due to firewall rules ISP restrictions or other requirements 3 10 6 SMTP...

Страница 38: ...report is issued So a typical strategy for using this selection page is as follows First select the severity level desired for reporting Typically this would be Critical and Error unless there is an...

Страница 39: ...gs are part of the Event Notification System discussed in Section 3 10 3 11 2 View Serial Logs Serial command activity can be initiated from the RS 232 connector or the Telnet interface Serial command...

Страница 40: ...ard this information to NCast for analysis 3 12 UPDATE TOOL The Update Tool page lists the current release s of software available for this Telepresenter If no information is listed then there is a pr...

Страница 41: ...ps Files which are missing or out of date are downloaded and installed The unit will then reboot and becomes ready for service again with the new software release Configuration files are not altered d...

Страница 42: ...Telepresenter The user is instructed to Use Channel 2 and no further detailed instructions are required When a Channel is started the Telepresenter begins its broadcast or recording Session All of the...

Страница 43: ...opying of the parameters from one channel to another 4 2 CHANNEL SETTINGS GENERAL 4 2 1 Channel Name Each channel can be assigned a name and these names can reflect the functional use of the channel F...

Страница 44: ...sion from some other source on this address Streaming Full Duplex The unit will be engaged in a two way simultaneous connection with one other Telepresenter Graphics and Audio generated on one unit wi...

Страница 45: ...oint connection is being established A full discussion of multicast addressing is beyond the scope of this document but briefly summarized there are three classes of multicast addresses typically used...

Страница 46: ...number will cause errors For multicast traffic to get through a firewall the even odd pair defined in this entry must be opened by the firewall administrator 4 2 6 Video Bit rate The video bit rate i...

Страница 47: ...ceptable 4 2 8 Video MTU The Maximum Transmission Unit MTU is the maximum length of a packet and is normally set to 1500 For some special circuits satellite links others the maximum size may need to b...

Страница 48: ...value for this field is 1 and a value of 127 or greater should be used for global transmission In some multicast networks TTL defines the scope or boundary conditions for containment of the multicast...

Страница 49: ...ation is not used SDP filename the name under which the SDP file is saved by the server Should have a sdp extension The names should be unique for each Telepresenter accessing a reflecting server 4 2...

Страница 50: ...nced checkbox is clicked 4 2 21 Bandwidth Smoothing If enabled the encoder smooths the stream transmission and sends packets at the prescribed target bit rate this is the default setting This will inc...

Страница 51: ...isible if the Channel is set to Full duplex or Receive If enabled audio and video is synchronized during playback to maintain lip sync this is the default setting If disabled audio and video is not sy...

Страница 52: ...te 00 to 59 n channel number 001 to 100 p AM or PM P am or pm S seconds 00 to 61 t transcode variable Y year For example if a Telepresenter user wishes to create a custom filename for the Accounting 1...

Страница 53: ...o on demand server specified on the Upload page Transcoding options are shown on the Modify Channel page when a Transcode box is checked Here you can assign a resolution graphics bit rate and a filena...

Страница 54: ...times to H 264 1920x1080 142 124 minutes 1280x720 109 101 minutes 640x360 53 51 minutes Transcoding times to Theora are quite lengthy because this first generation implementation has not yet been opt...

Страница 55: ...f the PIP window obscures any portion of the Main window It can be placed on top of or outside of the Main image Finally the Overlay Graphics or Text Overlays if preloaded and enabled are added to the...

Страница 56: ...e are automatically scaled to the Window dimen sions specified by the Main and PIP settings Frame size n The media streams and archive files are sent kept in a custom resolution Custom resolutions all...

Страница 57: ...Bottom left Bottom right would be chosen The custom window selections Window 1 Window 2 allow for placement of the primary and secondary images in arrangements not covered by the standard selections...

Страница 58: ...common selection would be one of the corner settings Top left Top right Bottom left Bottom right The custom window selections Window 1 Window 2 allow for placement of the PIP window in arrangements n...

Страница 59: ...More than one image all four in fact may be included if required The Channel Table Image Overlays are transferred to the operating Session parameters at Session startup and thus initialize the image o...

Страница 60: ...he Text Overlay in use during a Session may be made from the Sources page see Section 6 1 or from the Configuration menu see Section 3 5 4 6 1 State The enable disable setting will cause the text to b...

Страница 61: ...here Values must be in the range 0 255 For transparency 0 is fully transparent and 255 is opaque 4 6 9 Text The text to be displayed in the window This text may include format strings e g H M S for h...

Страница 62: ...0 N Channel name p AM PM P am pm R Archive presenter S Second 00 to 60 T Recording duration for example 01 45 12 x Date for example 12 31 08 X Time for example 23 13 48 Y Year for example 2009 z Numer...

Страница 63: ...n Archives tab Secure FTP SFTP is supported with password and private key authorization It will first try to use private key and if it fails password authorization is used Only SSH 2 protocol is suppo...

Страница 64: ...unique S FTP information different S FTP sites may be accessed by starting or using different Channels For example if the Session starting at 9 00 am needs to be uploaded to Dept A s server and the Se...

Страница 65: ...ntries required for this page 4 8 2 Channel N Settings Notification Events A subset of all system wide events is available for Channel specific notifications A system wide event would report the start...

Страница 66: ...ated during operation varies with the material being encoded and the calculation above should represent worst case conditions Archive files are named with time stamp information indicating the start t...

Страница 67: ...5 1 3 About Button This button allows downloading or viewing of the associated xml file This information is available in XML format for use by other applications xml version 1 0 encoding UTF 8 archive...

Страница 68: ...oaded to Dept B s server this is easily accomplished by specifying different S FTP sites in the Channel Table Or if some uploads go to a local on campus server and if other uploads go to a remote CDN...

Страница 69: ...ion JPEG or DV format for example where differential frame interpolation is no longer required Quicktime Pro an inexpensive add on to Quicktime player for both MACs and Windows is suitable for taking...

Страница 70: ...connector DVI Digital RGB signals from the DVI connector S Video Y C NTSC or PAL video from the auxiliary S video pin connector Composite NTSC or PAL video from the composite BNC connector The DVI inp...

Страница 71: ...rdware has only one video decoder and only Composite or S video may be selected as the video feed Thus there is no way to have an S video as a PIP on a Composite signal or to have a Composite signal a...

Страница 72: ...ession start using values from the Channel Table 6 1 11 Audio Microphone Gain The audio microphone gain adjusts the signal level from the microphone to the input of the AC 97 codec A reference signal...

Страница 73: ...ty and allows easier audio cable interface with professional sound systems The system detects an attached USB Matchbox on boot hot plug is not supported If the USB device is present a new option Audio...

Страница 74: ...inputs only 6 1 17 Video Preview This button launches a new web page with a single frame capture of the composite image currently being encoded and compressed Provides an excellent confidence check of...

Страница 75: ...ry to verify if the entry had been made correctly The Session Page also shows if the Session is currently active and the state of archiving Buttons on the page allow the operator to stop and start a S...

Страница 76: ...tion is derived from RTCP Real time Control Protocol reports and from information obtained through use of the NCast Conference Protocol The descriptive information comes from entries made in each unit...

Страница 77: ...participant has floor control by highlighting a Viewer and clicking on the selection 7 3 VIEW PAGE The View Page allows users at their desktops or laptops to launch client media players which will re...

Страница 78: ...Player RTSP in a Window rtp_live asx Windows RTP Playback rtsp_live asx Windows RTSP Playback live sdp Session Description Protocol File In all cases these files contain parameters such as the address...

Страница 79: ...g the viewer sees the media playback 7 4 VLC MEDIA PLAYER A popular cross platform media player with low latency is called VLC Video Lan Client There are several ways to launch VLC for use with a Tele...

Страница 80: ...player have not been configured correctly The audio has been muted 7 6 CLOSED CAPTION SUPPORT Section 508 of the Rehabilitation Act of 1973 is an amendment to a law requiring that electronic and IT te...

Страница 81: ...is no fully standardized mechanism for captioning across these technologies Each media player handles captions differently QuickTime does not currently support industry standard closed caption such a...

Страница 82: ...is the newest version and adds functionality for Flash and can play NCast s MPEG 4 media files The tool can be found here http ncam wgbh org webaccess magpie v2 World Caption is a program written by a...

Страница 83: ...esentation a 240x180 video shot of the instructor and a University logo with a copyright statement The proposed composite image should look like this To create this composite the following steps are r...

Страница 84: ...On the Sources page make these selections and press Update a Main input XGA or possibly DVI b PIP input Composite or possibly S Video The Telepresenter is now ready to transmit the composite image as...

Страница 85: ...r shot as a side by side layout is to position the window in the wrong spatial relationship to the screen being discussed by the presenter If the podium is to the right of the projection screen as vie...

Страница 86: ...or left side speaker placements the speakers naturally look at the projected graphics while presenting Here is an example of a mismatched left right alignment 8 1 4 Customer Layout Examples NCast cus...

Страница 87: ...nter Reference Manual HASTAC Conference courtesy of Duke University TeraGrid Conference courtesy of UCSD Virtual Teams Conference courtesy of Media X HP Historical Presentation NCast Corporation Revis...

Страница 88: ...terface One such program is called the Telepresenter Management System and there is a version written in Java and Python See the Download area of the NCast web site An example of the interface impleme...

Страница 89: ...The time stamped archive filename obtained from the downloaded list also wmv or ogg file xml The time stamped xml file associated with an archive file Note that archive operations are username passwo...

Страница 90: ...les Retrieving media file mp4 wget verbosity timestamping http user backup http passwd passwd http m4ip backup download mp4 if status 0 then echo m4files Error in accessing media file mp4 exit 1 endif...

Страница 91: ...files py telepresenter ncast com Download all files from a single host ncfiles py r telepresenter ncast com Download all files and then remove them ncfiles py 192 168 0 5 192 168 0 6 Download from mul...

Страница 92: ...ib import urllib2 import socket def Download host user pswd realm remove Create an OpenerDirector with support for Basic HTTP Authentication auth_handler urllib2 HTTPBasicAuthHandler auth_handler add_...

Страница 93: ...r return False fileout open mp4 wb while True try bytes filein read 1024000 fileout write bytes except IOError errno strerror print ncfiles I O error s s errno strerror sys exit 2 if bytes break filei...

Страница 94: ...ue Main Program hostlist debug False inputfile None user backup pswd ncast realm NCast M3 remove False def Usage print Usage ncfiles py d f hostfile h p password r v debug file hostfile help pswd pass...

Страница 95: ...swd realm remove if not result print ncfiles Download error on host host print ncfiles Download complete 9 4 HTTP INTERFACE IMAGE AND THUMBNAIL CAPTURE The HTTP Interface may be used to capture single...

Страница 96: ...allows custom templates to be changed on an hourly basis for example A single command line using a widely available utility is enough to upload a single graphic curl u api ncast F overlay_1_file test...

Страница 97: ...1 2 3 4 g1 g2 g3 g4 imgnum int optname 1 if not os path exists optvalue raise Exception Invalid image file optvalue images imgnum optvalue else raise Exception BUG should have caught s but didn t opt...

Страница 98: ...rrno strerror print ncgo Socket error s for host s s errno host strerror sys exit 1 print ncgo finished def encode_multipart_formdata fields boundary mimetools choose_boundary lines for key in fields...

Страница 99: ...ved viewers will see various artifacts pixelation stuttering loss of lip sync that lead to a negative experience The principal causes of these artifacts are packet loss due to overloading of the inter...

Страница 100: ...s battery icons or other clutter on the signal being captured There are usually menu options to turn these information icons off Arrange with the conference staff to have one or two spotlights on the...

Страница 101: ...eo Swap Usually during conferences there are periods when no active or meaningful graphics are being displayed e g during Q A sessions panel commentaries introductions Be prepared to swap the video an...

Страница 102: ...of the projection screen Talking in front of the projection screen leads to video backlighting problems and should be avoided Start of Talk Ideally the presenter s discussion should start once the pr...

Страница 103: ...our new clip and select the In point where the new clip should start Align the In point to the nearest key frame This is required to eliminate pixelation and picture breakup at the start of the new cl...

Страница 104: ...ew clip and select an Out point where the new clip ends Save the file as a new mp4 file You should override the mov suggested suffix with mp4 If this file will be used on a streaming server the hint t...

Страница 105: ...of MPEG 4 Elementary Streams J van der Meer et al November 2003 IETF RFC 2326 Real Time Streaming Protocol RTSP H Schulzrinne et al April 1998 IETF RFC 2327 SDP Session Description Protocol M Handley...

Страница 106: ...dditional support for sub title events and Chaptering Increased Overlay storage space Overlay buttons on the Sources page Additional tags in the XML file for format description CIDR notation added to...

Страница 107: ...t option is now available for a Channel The Archive detail files now support Unicode and are in XML format The txt files are no longer available Revision 1 0 Initial revision based on software Release...

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