Itview Modules

Owned by Cottalango Leon
Last updated: Mar 31, 2021
2 min read



List of internal modules used by itview. Those that are already implemented as re-usable modules and used outside the itview application are highlighted in blue. All the modules are written in python 2.x unless specified otherwise.



Techstack

  • Python, PyQt, Cython, C++, Scala



GUI

  • PyQt v4 (PySide compatible)



Viewport

  • OpenGL based “layer stack”



Playback Engine

  • Timecube (timing module) that takes over the Qt event loop

  • Videostreamer, manages read-ahead logic for video and invoking the read codecs

  • Audiostreamer, same as videostreamer but for audio



I/O Layer

  • OIIO for individual image files (C++)

  • FileSequence (C++)

  •  

    • Understands individual image files for a rendered sequence

  • SpMovie (C++)

  •  

    • Wrapper around third party libraries and internal movie formats (h264, J2K codecs)

    • Internal movie file format using J2K with DCP compliant encoding (12 bit depth)

    • Ffmpeg based libraries for most third party movie file formats

  • MediaCache

  •  

    • Finds the physical media on disk based on tracking number

  • VirtualMedia

  •  

    • Programmatically generate frames for blackframes, error card, contact sheet, title cards

  • Media layer that abstracts all video, audio I/O

  •  

    • Support pixel probing

    • Recognize colorspace, aspect ratio, stereo



Playlist

  • Manages a list of clips (media with video and/or audio)

  • Clip can have one video and/or audio

  • Manages metadata with playlists, clips and the media objects themselves

  • Transitions: cross-dissolves and wipes

  • Timewarps: customize the order of frames for playback, holding frames, speed changes etc

  • Playlist files are in XML format



Database Layer

  • Shotgun (Production tracking)

  • Edbot (Editorial tracking: proprietary, maybe replaced with OTIO in the future)

  • VFO (review notes)

  • VnP (Versioning and Publishing - proprietary asset management system)



Annotations

  • Supports

  •  

    • Scribbles with various Brushes, Text, Color Corrections (rectangles, ellipses and lasso)

  • Vector format (resolution independent), stored as XML in database

  • Internal API for storing and retrieving

  • Would be great to move to an interchangeable format+API (OTIO, USD)



Color Pipeline

  • OCIO (C++)

  • Color correction operations are sent as OCIO requests and rendered

  • Aware of display devices being used and will choose the correct look



Misc

  • FCurve

  • FTGL/Freetype

  • FormWidgets

  • ResolutionTable

  • StereoConvergence



Plugins

  • Python based

  • Internal “pyCore” module exposes most of core itview functionality to plugins



Messaging

  • PyQt signals/slots

  • ZeroC ICE api

  • Sockets



Remote Sync

  • Sync Server (Scala)

  •  

    • Separate project, written in Scala for high performance

  • Itview clients talk to it via ZeroC ICE api protocol

  • Manages permissions and access controls for remote users

  • Host itview Qt events and API calls are broadcast to remote clients

  • Sync sessions provide a “headless itview” with it’s entire state backed by a database

  • Public (show based) /private user based sessions as well as internal “context view playlists”

  •  

    • Aware of editorial information for sequence/shots