flexible and can be used also for other things.
Before reading trying to use video inputs, you should read and understand how
-themes work in general (see :doc:`theme`). Video inputs are available from
-Nageru 1.6.0 onwards, and from Nageru 1.7.2, you can get audio from video inputs
+themes work in general (see :doc:`theme`). You can get audio from video inputs
like any other input. (Be advised, though, that making a general video player
that can maintain A/V sync on all kinds of video files is a hard problem,
so there may still be bugs in this support.)
must be *loaded*, giving it an identifier, and then that video can be used
as inputs in a chain, much like :ref:`images <images>` or regular live inputs.
Anything FFmpeg accepts, including network streams, can be used (probably even
-V4L input cards, although this is untested).
+V4L input cards, although this is untested). Video hardware acceleration is used
+if available, although the decoded data currently takes a round trip through
+the GPU.
When loading a video, you need to decide what format to use; Y'CbCr or BGRA.
(Whatever you choose, if you get a mismatch with what the video actually is in,
local video = VideoInput.new("http://localhost/file.nut", Nageru.VIDEO_FORMAT_BGRA)
-It can then be added to any chain like this::
+It can then be display on an input like usual::
- local input = chain:add_video_input(video, false)
+ input:display(video)
-The second parameter specifies no deinterlacing. Note that interlaced video
-is currently not supported, not even with deinterlacing, so this parameter
-must always be false.
-
-You can use the same video object to create many different video inputs::
-
- local input1 = chain1:add_video_input(video, false)
- local input2 = chain2:add_video_input(video, false)
+Note that interlaced video is currently not supported, not even with deinterlacing.
Videos run in the correct frame rate and on their own timer (generally the
system clock in the computer), and loop when they get to the end or whenever an
stretching or change the pitch accordingly.
Finally, if you want to forcibly abort the playing of a video,
-even one that is blocking on I/O, you can use (since Nageru 1.7.2)::
+even one that is blocking on I/O, you can use::
video:disconnect()
always properly detect if the connection has been lost. See :ref:`menus`
for a way to expose such functionality to the operator.
+.. _subtitle-ingest:
+
+Ingesting subtitles
+-------------------
-Integration with CasparCG
--------------------------
+Video streams can contain separate subtitle tracks. This is particularly useful when using Nageru
+and Futatabi together (see :ref:`talkback`).
-This section has been removed, as since 1.7.0, Nageru has :doc:`native support for HTML5 inputs <html>`,
-obsoleting CasparCG integration.
+To get the last subtitle given before the current video frame, call
+“signals:get_last_subtitle(n)” from get_chain, where n is the signal number
+of your video signal. It will either contain nil, if there hasn't been
+a subtitle, or else the raw subtitle. Note that if the video frame and
+the subtitle occur on the exact same timestamp, and the video frame
+is muxed before the subtitle packet, the subtitle will not make it in time.
+(Futatabi puts the subtitle slightly ahead of the video frame to avoid this.)