Properly scale vertical encodes to 4K (#23)

Properly scale vertical encodes to 4K

For vertical encodes, YouTube will not process them in 4K and instead in 1440p as the height is always fixed to 2160. This fixes it. Also takes into account the 3840 height limit for vertical encodes.

Author: despoa

encode.avs

@@ -156,35 +156,40 @@ if (prescaleFactor > 1 && !hd) {
 #	Aspect ratio correction for SD encodes
 #	if dimensions are not multiples of 4, codecs freak out, so we enforce mod 4
 mod		= 4
-hdHeight= 2160
 height	= last.height.ForceModulo(mod, true)
 width	= (ARCorrection \
 		? height * wAspect / hAspect \
 		: last.width) \
 		.ForceModulo(mod, true)
 
-#	Remember SD frame size for subYpos HD tweaks
-wARC	= width
-hARC	= height
-
 #	Actually go HD if we need
 if (hd) {
-	height = hdHeight
-}
-
-width	= (ARCorrection \
-		? height * wAspect / hAspect \
-		: height * last.width / last.height) \
-		.ForceModulo(mod, true)
-hStretch= height / last.height
-
-# YouTube has a 4K width limit of 3840
-if (hd && (width > 3840)) {
-	width = 3840
-	height = (ARCorrection \
-		? width * hAspect / wAspect \
-		: width * last.height / last.width) \
-		.ForceModulo(mod, true)
+	vertical        = width < height
+	
+	normalAspect	= ARCorrection ? float(wAspect) / hAspect \
+		: float(last.width) / last.height
+	reverseAspect	= ARCorrection ? float(hAspect) / wAspect \
+		: float(last.height) / last.width
+	
+	if (vertical) {
+		temp		= normalAspect
+		normalAspect	= reverseAspect
+		reverseAspect	= temp
+	}
+	
+	smallerSideCap  = 2160
+	biggerSideCap   = 3840
+	
+	smallerSideHD	= smallerSideCap
+	biggerSideHD	= int(smallerSideHD * normalAspect).ForceModulo(mod, true)
+	
+	if (biggerSideHD > biggerSideCap) {
+		biggerSideHD	= biggerSideCap
+		smallerSideHD	= int(biggerSideHD * reverseAspect).ForceModulo(mod, true)
+	}
+	
+	width	= vertical ? smallerSideHD : biggerSideHD
+	height	= vertical ? biggerSideHD  : smallerSideHD
 }
 
 #	Rescaling