From 1f13b613f7018b66d050fcde36cf401f8a66baec Mon Sep 17 00:00:00 2001 From: "Steinar H. Gunderson" Date: Sun, 23 Dec 2018 00:29:31 +0100 Subject: [PATCH] Start documenting Futatabi. --- futatabi.rst | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++ index.rst | 1 + 2 files changed, 64 insertions(+) create mode 100644 futatabi.rst diff --git a/futatabi.rst b/futatabi.rst new file mode 100644 index 0000000..557032e --- /dev/null +++ b/futatabi.rst @@ -0,0 +1,63 @@ +Futatabi: Real-time instant replay with slow motion +=================================================== + +Futatabi (after the Japanese word *futatabi*, 再び, meaning “again” or +“for the second time”) is a system for instant replay. Even though Futatabi +is meant to be used with Nageru, shares some code with it and is built from +the same source distribution (with matching version numbers), it is a separate +application. Futatabi is meant for slow motion for e.g. sports broadcasts, but +can also be used as a more generic multitrack recorder for later editing. + +Futatabi supports *interpolated* slow motion, meaning you do not need to buy +a high-speed 120 fps camera to get smooth 60 fps output after slowdown—Futatabi +will automatically synthesize in-between frames for you during playback. +Good interpolation, especially in realtime, is a difficult problem, and not all +content will do equally well. Most content should do quite acceptably, especially +considering that half of the frames will actually be originals, but you +will need to see in practice what actually works for you. Interpolation can +also be used for frame rate conversion (e.g. 50 to 59.94 fps). + +Futatabi currently uses a GPU reimplementation of +`Fast Optical Flow using Dense Inverse Search (DIS) `_ +by Kroeger et al, although this may change in the future. + + +System requirements +------------------- + +It is strongly recommended to run Futatabi on a separate machine from Nageru, +not the least because you probably want a different person to operate the replay +while the producer is operating Nageru. + +Like Nageru, Futatabi uses your GPU for nearly all image processing. +However, unlike Nageru, Futatabi requires a powerful GPU for interpolation; +a GTX 1080 or similar is recommended for interpolated 720p60. (Futatabi +was initially developed on a GTX 950, which is passable, but has little +performance margin.) If you have a slower GPU and are happy with worse +quality, or just wish to test, you can use a faster preset, or turn off +interpolation entirely. Futatabi requires OpenGL 4.5 or newer. + +For other required libraries, see :doc:`compile`; when you build Nageru, +you also compile Futatabi. + + +Getting started +--------------- + +Sample multicamera data +''''''''''''''''''''''' + +Transferring data to and from Nageru +------------------------------------ + +Video format specification +'''''''''''''''''''''''''' + +Monitoring +---------- + +Tally and status talkback +''''''''''''''''''''''''' + +Prometheus metrics +'''''''''''''''''' diff --git a/index.rst b/index.rst index 61954a0..463d9f5 100644 --- a/index.rst +++ b/index.rst @@ -21,6 +21,7 @@ Contents: video html monitoring + futatabi :ref:`search` -- 2.39.2