diff --git a/indra/llcharacter/llbvhloader.h b/indra/llcharacter/llbvhloader.h
index de16d86ff4..c2c755664e 100755
--- a/indra/llcharacter/llbvhloader.h
+++ b/indra/llcharacter/llbvhloader.h
@@ -296,6 +296,10 @@ public:
 
 	ELoadStatus getStatus() { return mStatus; }
 
+	// <FS:Sei> FIRE-17277: Allow entering Loop In/Loop Out as frames
+	S32 getNumFrames() { return mNumFrames; }
+	// </FS:Sei>
+
 protected:
 	// Consumes one line of input from file.
 
diff --git a/indra/newview/llfloaterbvhpreview.cpp b/indra/newview/llfloaterbvhpreview.cpp
index 3b1aee77d1..4ad9774397 100755
--- a/indra/newview/llfloaterbvhpreview.cpp
+++ b/indra/newview/llfloaterbvhpreview.cpp
@@ -176,6 +176,12 @@ void LLFloaterBvhPreview::setAnimCallbacks()
 	getChild<LLUICtrl>("loop_in_point")->setValidateBeforeCommit( boost::bind(&LLFloaterBvhPreview::validateLoopIn, this, _1));
 	getChild<LLUICtrl>("loop_out_point")->setCommitCallback(boost::bind(&LLFloaterBvhPreview::onCommitLoopOut, this));
 	getChild<LLUICtrl>("loop_out_point")->setValidateBeforeCommit( boost::bind(&LLFloaterBvhPreview::validateLoopOut, this, _1));
+	// <FS:Sei> FIRE-17277: Allow entering Loop In/Loop Out as frames
+	getChild<LLUICtrl>("loop_in_frames")->setCommitCallback(boost::bind(&LLFloaterBvhPreview::onCommitLoopInFrames, this));
+	getChild<LLUICtrl>("loop_in_frames")->setValidateBeforeCommit( boost::bind(&LLFloaterBvhPreview::validateLoopInFrames, this, _1));
+	getChild<LLUICtrl>("loop_out_frames")->setCommitCallback(boost::bind(&LLFloaterBvhPreview::onCommitLoopOutFrames, this));
+	getChild<LLUICtrl>("loop_out_frames")->setValidateBeforeCommit( boost::bind(&LLFloaterBvhPreview::validateLoopOutFrames, this, _1));
+	// </FS:Sei>
 
 	getChild<LLUICtrl>("hand_pose_combo")->setCommitCallback(boost::bind(&LLFloaterBvhPreview::onCommitHandPose, this));
 	
@@ -329,6 +335,20 @@ BOOL LLFloaterBvhPreview::loadBVH()
 		// motion will be returned, but it will be in a load-pending state, as this is a new motion
 		// this motion will not request an asset transfer until next update, so we have a chance to 
 		// load the keyframe data locally
+		// <FS:Sei> FIRE-17277: Allow entering Loop In/Loop Out as frames
+		mNumFrames = loaderp->getNumFrames();
+		getChild<LLSpinCtrl>("loop_in_frames")->setMaxValue(LLSD((F32)mNumFrames));
+		getChild<LLSpinCtrl>("loop_out_frames")->setMaxValue(LLSD((F32)mNumFrames));
+		// (Re)assign loop frames spinners from loop percentages.
+		getChild<LLUICtrl>("loop_in_frames")->setValue(LLSD((F32)getChild<LLUICtrl>("loop_in_point")->getValue().asReal() / 100.f * (F32)mNumFrames));
+		getChild<LLUICtrl>("loop_out_frames")->setValue(LLSD((F32)getChild<LLUICtrl>("loop_out_point")->getValue().asReal() / 100.f * (F32)mNumFrames));
+
+		LLUIString out_str = getString("FS_report_frames");
+		out_str.setArg("[F]", llformat("%d", mNumFrames));
+		out_str.setArg("[S]", llformat("%.1f", loaderp->getDuration()));
+		out_str.setArg("[FPS]", llformat("%.1f", (F32)mNumFrames / loaderp->getDuration()));
+		getChild<LLUICtrl>("frames_label")->setValue(LLSD(out_str));
+		// </FS:Sei>
 		// <FS> Preview on own avatar
 		//motionp = (LLKeyframeMotion*)mAnimPreview->getDummyAvatar()->createMotion(mMotionID);
 		motionp =  dynamic_cast<LLKeyframeMotion*>(mAnimPreview->getPreviewAvatar(this)->createMotion(mMotionID));
@@ -869,7 +889,10 @@ void LLFloaterBvhPreview::onCommitLoopIn()
 
 	if (motionp)
 	{
-		motionp->setLoopIn((F32)getChild<LLUICtrl>("loop_in_point")->getValue().asReal() / 100.f);
+		// <FS:Sei> FIRE-17277: Allow entering Loop In/Loop Out as frames
+		//motionp->setLoopIn((F32)getChild<LLUICtrl>("loop_in_point")->getValue().asReal() / 100.f);
+		getChild<LLUICtrl>("loop_in_frames")->setValue(LLSD((F32)getChild<LLUICtrl>("loop_in_point")->getValue().asReal() / 100.f * (F32)mNumFrames));
+		// </FS:Sei>
 		resetMotion();
 		getChild<LLUICtrl>("loop_check")->setValue(LLSD(TRUE));
 		onCommitLoop();
@@ -893,13 +916,61 @@ void LLFloaterBvhPreview::onCommitLoopOut()
 
 	if (motionp)
 	{
-		motionp->setLoopOut((F32)getChild<LLUICtrl>("loop_out_point")->getValue().asReal() * 0.01f * motionp->getDuration());
+		// <FS:Sei> FIRE-17277: Allow entering Loop In/Loop Out as frames
+		//motionp->setLoopOut((F32)getChild<LLUICtrl>("loop_out_point")->getValue().asReal() * 0.01f * motionp->getDuration());
+		getChild<LLUICtrl>("loop_out_frames")->setValue(LLSD((F32)getChild<LLUICtrl>("loop_out_point")->getValue().asReal() / 100.f * (F32)mNumFrames));
+		// </FS:Sei>
 		resetMotion();
 		getChild<LLUICtrl>("loop_check")->setValue(LLSD(TRUE));
 		onCommitLoop();
 	}
 }
 
+// <FS:Sei> FIRE-17277: Allow entering Loop In/Loop Out as frames
+//-----------------------------------------------------------------------------
+// onCommitLoopInFrames()
+//-----------------------------------------------------------------------------
+void LLFloaterBvhPreview::onCommitLoopInFrames()
+{
+	if (!getEnabled() || !mAnimPreview)
+		return;
+
+	// Preview on own avatar
+	LLVOAvatar* avatarp = mAnimPreview->getPreviewAvatar(this);
+	LLKeyframeMotion* motionp = (LLKeyframeMotion*)avatarp->findMotion(mMotionID);
+
+	if (motionp)
+	{
+		getChild<LLUICtrl>("loop_in_point")->setValue(LLSD(mNumFrames == 0 ? 0.f : 100.f * (F32)getChild<LLUICtrl>("loop_in_frames")->getValue().asReal() / (F32)mNumFrames));
+		resetMotion();
+		getChild<LLUICtrl>("loop_check")->setValue(LLSD(TRUE));
+		// The values are actually set here:
+		onCommitLoop();
+	}
+}
+
+//-----------------------------------------------------------------------------
+// onCommitLoopOutFrames()
+//-----------------------------------------------------------------------------
+void LLFloaterBvhPreview::onCommitLoopOutFrames()
+{
+	if (!getEnabled() || !mAnimPreview)
+		return;
+
+	// Preview on own avatar
+	LLVOAvatar* avatarp = mAnimPreview->getPreviewAvatar(this);
+	LLKeyframeMotion* motionp = (LLKeyframeMotion*)avatarp->findMotion(mMotionID);
+
+	if (motionp)
+	{
+		getChild<LLUICtrl>("loop_out_point")->setValue(LLSD(mNumFrames == 0 ? 100.f : 100.f * (F32)getChild<LLUICtrl>("loop_out_frames")->getValue().asReal() / (F32)mNumFrames));
+		resetMotion();
+		getChild<LLUICtrl>("loop_check")->setValue(LLSD(TRUE));
+		onCommitLoop();
+	}
+}
+// </FS:Sei>
+
 //-----------------------------------------------------------------------------
 // onCommitName()
 //-----------------------------------------------------------------------------
@@ -1083,6 +1154,9 @@ bool LLFloaterBvhPreview::validateLoopIn(const LLSD& data)
 	}
 
 	getChild<LLUICtrl>("loop_in_point")->setValue(LLSD(loop_in_value));
+	// <FS:Sei> FIRE-17277: Allow entering Loop In/Loop Out as frames
+	getChild<LLUICtrl>("loop_in_frames")->setValue(LLSD(loop_in_value / 100.f * (F32)mNumFrames));
+	// </FS:Sei>
 	return true;
 }
 
@@ -1111,10 +1185,74 @@ bool LLFloaterBvhPreview::validateLoopOut(const LLSD& data)
 	}
 
 	getChild<LLUICtrl>("loop_out_point")->setValue(LLSD(loop_out_value));
+	// <FS:Sei> FIRE-17277: Allow entering Loop In/Loop Out as frames
+	getChild<LLUICtrl>("loop_out_frames")->setValue(LLSD(loop_out_value / 100.f * (F32)mNumFrames));
+	// </FS:Sei>
 	return true;
 }
 
 
+// <FS:Sei> FIRE-17277: Allow entering Loop In/Loop Out as frames
+//-----------------------------------------------------------------------------
+// validateLoopInFrames()
+//-----------------------------------------------------------------------------
+bool LLFloaterBvhPreview::validateLoopInFrames(const LLSD& data)
+{
+	if (!getEnabled())
+		return false;
+
+	F32 loop_in_value = (F32)getChild<LLUICtrl>("loop_in_frames")->getValue().asReal();
+	F32 loop_out_value = (F32)getChild<LLUICtrl>("loop_out_frames")->getValue().asReal();
+
+	if (loop_in_value < 0.f)
+	{
+		loop_in_value = 0.f;
+	}
+	else if (loop_in_value > 100.f)
+	{
+		loop_in_value = 100.f;
+	}
+	else if (loop_in_value > loop_out_value)
+	{
+		loop_in_value = loop_out_value;
+	}
+
+	getChild<LLUICtrl>("loop_in_frames")->setValue(LLSD(loop_in_value));
+	getChild<LLUICtrl>("loop_in_point")->setValue(LLSD(mNumFrames == 0 ? 0.f : 100.f * loop_in_value / (F32)mNumFrames));
+	return true;
+}
+
+//-----------------------------------------------------------------------------
+// validateLoopOutFrames()
+//-----------------------------------------------------------------------------
+bool LLFloaterBvhPreview::validateLoopOutFrames(const LLSD& data)
+{
+	if (!getEnabled())
+		return false;
+
+	F32 loop_out_value = (F32)getChild<LLUICtrl>("loop_out_frames")->getValue().asReal();
+	F32 loop_in_value = (F32)getChild<LLUICtrl>("loop_in_frames")->getValue().asReal();
+
+	if (loop_out_value < 0.f)
+	{
+		loop_out_value = 0.f;
+	}
+	else if (loop_out_value > 100.f)
+	{
+		loop_out_value = 100.f;
+	}
+	else if (loop_out_value < loop_in_value)
+	{
+		loop_out_value = loop_in_value;
+	}
+
+	getChild<LLUICtrl>("loop_out_frames")->setValue(LLSD(loop_out_value));
+	getChild<LLUICtrl>("loop_out_point")->setValue(LLSD(mNumFrames == 0 ? 100.f : 100.f * loop_out_value / (F32)mNumFrames));
+	return true;
+}
+// </FS:Sei>
+
+
 //-----------------------------------------------------------------------------
 // refresh()
 //-----------------------------------------------------------------------------
diff --git a/indra/newview/llfloaterbvhpreview.h b/indra/newview/llfloaterbvhpreview.h
index 6b7e6c3c5d..a803c411ba 100755
--- a/indra/newview/llfloaterbvhpreview.h
+++ b/indra/newview/llfloaterbvhpreview.h
@@ -116,6 +116,12 @@ public:
 									   LLAssetType::EType type,
 									   void* user_data,
 									   S32 status, LLExtStat ext_status);
+	// <FS:Sei> FIRE-17277: Allow entering Loop In/Loop Out as frames
+	void onCommitLoopInFrames();
+	void onCommitLoopOutFrames();
+	bool validateLoopInFrames(const LLSD& data);
+	bool validateLoopOutFrames(const LLSD& data);
+	// </FS:Sei>
 private:
 	void setAnimCallbacks() ;
 	// <FS> Reload animation from disk
@@ -146,6 +152,9 @@ protected:
 
 	// <FS:Ansariel> FIRE-2083: Slider in upload animation floater doesn't work
 	LLFrameTimer		mTimer;
+
+	// <FS:Sei> FIRE-17277: Allow entering Loop In/Loop Out as frames
+	S32					mNumFrames;
 };
 
 #endif  // LL_LLFLOATERBVHPREVIEW_H
diff --git a/indra/newview/skins/default/xui/en/floater_animation_bvh_preview.xml b/indra/newview/skins/default/xui/en/floater_animation_bvh_preview.xml
index 453a92c5e5..ef02e1e690 100755
--- a/indra/newview/skins/default/xui/en/floater_animation_bvh_preview.xml
+++ b/indra/newview/skins/default/xui/en/floater_animation_bvh_preview.xml
@@ -2,7 +2,7 @@
 <floater
  legacy_header_height="18"
  can_minimize="false"
- height="415"
+ height="450"
  left="30"
  layout="topleft"
  name="Animation Preview"
@@ -150,6 +150,10 @@ Maximum animation length is [MAX_LENGTH] seconds.
      name="E_ST_BAD_ROOT">
         Incorrect root joint name, use "hip".
     </floater.string>
+    <floater.string
+     name="FS_report_frames">
+        [F] frm.  [S] s. [FPS] fps
+    </floater.string>
   <text
      type="string"
      length="1"
@@ -204,7 +208,7 @@ Maximum animation length is [MAX_LENGTH] seconds.
      width="160" />
     <check_box
      top_pad="0"
-     height="14"
+     height="23"
      label="Loop"
      layout="topleft"
      left="10"
@@ -212,6 +216,19 @@ Maximum animation length is [MAX_LENGTH] seconds.
      initial_value="false"
      name="loop_check"
      tool_tip="Makes this animation loop" />
+    <text
+     type="string"
+     length="1"
+     top_pad="5"
+     follows="top|left"
+     height="23"
+     layout="topleft"
+     left_pad="5"
+     bottom_delta="8"
+     width="160"
+     name="frames_label">
+       300 frm. 30 s. 10 fps
+    </text>
     <spinner
      follows="left|top"
      height="23"
@@ -240,6 +257,32 @@ Maximum animation length is [MAX_LENGTH] seconds.
      tool_tip="Sets point in animation that ends a loop"
      label_width="60"
      width="120" />
+    <spinner
+     follows="left|top"
+     height="23"
+     increment="1"
+     label="In(frm)"
+     label_width="70"
+     layout="topleft"
+     top_pad="5"
+     left="15"
+     max_val="1000"
+     name="loop_in_frames"
+     tool_tip="Sets point in animation that looping returns to, in frames"
+     width="130" />
+    <spinner
+     bottom_delta="0"
+     follows="left|top"
+     height="23"
+     increment="1"
+     label="Out(frm)"
+     layout="topleft"
+     left_pad="10"
+     max_val="1000"
+     name="loop_out_frames"
+     tool_tip="Sets point in animation that ends a loop, in frames"
+     label_width="60"
+     width="120" />
     <text
      type="string"
      length="1"
@@ -553,6 +596,7 @@ Maximum animation length is [MAX_LENGTH] seconds.
      follows="top|left"
      layout="topleft"
      left="70"
+     width="200"
      name="bad_animation_text">
         Unable to read animation file.
 We recommend BVH files exported from Poser 4.