[NUT-devel] [nut]: r588 - docs/nut.txt

[michael]

Author: michael
Date: Tue Feb  5 15:54:07 2008
New Revision: 588

Log:
Add a unknown match_time_delta value and use this as default.
That way "old" nut files will have unspecified match_time_delta instead of
all 0. And new muxers arent forced to know all match_time_delta.
Comments welcome. An alternative would be to require specified match_time_delta
but that could be tricky to find out in some cases, and no other container
contains this info.


Modified:
   docs/nut.txt

Modified: docs/nut.txt
==============================================================================
--- docs/nut.txt	(original)
+++ docs/nut.txt	Tue Feb  5 15:54:07 2008
@@ -247,7 +247,7 @@ main_header:
     tmp_pts=0
     tmp_mul=1
     tmp_stream=0
-    tmp_match=0
+    tmp_match=1-(1<<62)
     for(i=0; i<256; ){
         tmp_flag                        v
         tmp_fields                      v
@@ -683,6 +683,10 @@ match_time_delta
     the output from the decoder has converged independent from the availability
     of previous frames (that is the frames are virtually identical no matter
     if decoding started from the very first frame or from this keyframe).
+    If its value is 1-(1<<62) then match_time_delta is unspecified, that is
+    the muxer didnt have enough knowledge to set it.
+    A muxer MUST only set it to 1-(1<<62) if it does not know the correct
+    value. That is, it is not allowed to randomly discard known values.
 
 lsb_pts
     Least significant bits of the pts in time_base precision.