X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=hdmisdi.rst;h=7c8a0c6e6654b9efc4fe8a13ab480645edd9a0c1;hb=a6edc4466735e82826fe5e47a2b582498f74d404;hp=339e64c582f7232e625056e2af6ce6ad6c56fcc9;hpb=16be766b873f0a310f2d359a4097e06bc5ba29d2;p=nageru-docs

diff --git a/hdmisdi.rst b/hdmisdi.rst
index 339e64c..7c8a0c6 100644
--- a/hdmisdi.rst
+++ b/hdmisdi.rst
@@ -17,7 +17,7 @@ Setting up HDMI/SDI output
 
 Turning on HDMI/SDI output is simple; just right-click on the live view and
 select the output card. (Equivalently, you can access the same functionality
-from the _Video_ menu in the regular menu bar.) Currently, this is supported
+from the *Video* menu in the regular menu bar.) Currently, this is supported
 for DeckLink cards only (PCI/Thunderbolt), as the precise output protocol for
 the Intensity Shuttle cards is still unknown. The stream and recording will
 keep running just as before.
@@ -101,7 +101,24 @@ tradeoffs must be made. The most important sources of latency are:
    The 4K series in this context include everything that have “4K” in their
    names, plus the Mini Recorder, Duo 2 and Quad 2 devices.
 
-TODO: Write about queuing options. And latency measurements. And audio.
+Controlling latency
+...................
+
+Of the different sources of latency outlined in the previous section,
+the only one that is really under your control (short of buying faster
+or better hardware) is the input queue latency. By default, Nageru
+attempts to strike a balance between reducing latency and having to
+drop frames due to jitter; by looking at each queue's input length
+history, it attempts to find a “safe queue limit”, above which it
+can drop frames without risking underrun (which requires duplicating
+frames). However, if latency is more important to you than 100% smooth
+motion, you can override this by using the *--max-input-queue-frames=*
+flag; this is a hard limit on the number of frames that can be kept
+in the queue, on top of Nageru's own heuristics. It cannot be set lower
+than 1, or else all incoming frames would immediately get dropped
+on arrival.
+
+TODO: Write about output queuing options. And latency measurements. And audio.
 
 TODO: Write something about time codes here.