X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=video.rst;h=c41099d6e8aa2db0f4eb38d621acf35dae0c807a;hb=8e3c22eaf1cc06eaedaa7442d67c59dc1ad0e0ca;hp=e1f1eb54aec8932bf7d2ab26436c3e52ed0cbdca;hpb=826c5e117b2746ca665fdd10d4685beed78d367a;p=nageru-docs

diff --git a/video.rst b/video.rst
index e1f1eb5..c41099d 100644
--- a/video.rst
+++ b/video.rst
@@ -32,15 +32,15 @@ and/or it has an alpha channel you want to use. Getting the format right makes
 for better efficiency; you not only save a conversion step on the CPU, but
 sometimes also on the GPU.
 
-Videos are loaded like this:
+Videos are loaded like this::
 
   local video = VideoInput.new("filename.mp4", Nageru.VIDEO_FORMAT_YCBCR)
 
-or, for a network stream, perhaps:
+or, for a network stream, perhaps::
 
   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 added to any chain like this::
 
   local input = chain:add_video_input(video, false)
 
@@ -48,7 +48,7 @@ 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:
+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)
@@ -61,11 +61,37 @@ moving the new file atomically into place, you could end up corrupting the file
 Nageru is playing from, causing it to automatically rewind before the end of
 the segment.
 
+Videos are assigned an arbitrary signal number when loaded. Whenever you need
+to refer to this signal number (say, to get its width or height for display),
+you should use *video:get_signal_num()*. Like any other signal, videos have
+a width and height, an interlaced flag (currently always false), a frame rate
+(which can vary during playback) and has_signal/is_connected member functions.
+The former is always true, but the former will be false if the video isn't
+currently playing for whatever reason (e.g., the file is corrupted, or a network
+stream is broken and hasn't reconnected yet).
+
 
 Controlling video playback
 --------------------------
 
-TODO
+Themes have some programmatic control over video playback. In particular,
+if you want to make a video start from the beginning, you can do::
+
+  video:rewind()
+
+which will instantly make it start from the first frame again. This can be
+useful if you e.g. want the video to start when you're switching to it,
+or if you're not really using it to loop (e.g. as a transition marker).
+
+You can also change its rate, e.g. by::
+
+  video:change_rate(2.0)
+
+This will make it play at twice its usual speed. Your rate should not be
+negative nor exactly zero. You can set a rate to e.g. 1e-6 if you want to
+in practice stop the video; once you change it back to normal speed,
+the next frame will resume playing.
+
 
 Integration with CasparCG
 -------------------------