follow x264's default keyint-min behavior

[Steve Borho]

x265 currently sets keyint-min to be equal to keyint-max if it is not assigned. I'm pretty sure x264 does something different. We should follow their approach

[Former user]

Well, if keymin isn't manually set, x264 would choose min(fps, keymax/10). Excessive values are also clipped to [1, keymax/2 + 1].

diff -r 23c65133c555 source/encoder/encoder.cpp
--- a/source/encoder/encoder.cpp    Thu Jan 23 20:41:05 2014 -0600
+++ b/source/encoder/encoder.cpp    Thu Jan 23 20:14:37 2014 -0800
@@ -1264,8 +1264,9 @@
     }
     if (!_param->keyframeMin)
     {
-        _param->keyframeMin = _param->keyframeMax;
+        _param->keyframeMin = X265_MIN(_param->frameRate, _param->keyframeMax / 10);
     }
+    _param->keyframeMin = X265_MAX(1, X265_MIN(_param->keyframeMin, _param->keyframeMax / 2 + 1));
     if (_param->keyframeMax <= 1)
     {
         // disable lookahead for all-intra encodes

[Steve Borho]

nice, thanks. I've applied this

[Steve Borho]

follow x264's keyframe-min logic [CHANGES OUTPUTS] (closes #24)

If no --keyint-min is specified, default to max/10, and clamp the value to between [1, max / 2 + 1]. This allows x265 to insert I frames when scene cuts are detected between keyframe-min and keyframe-max

→ <<cset 898ccce491e9>>