From 117a75ae554e5ffcdb3f97c0d9c0d3584eb1008a Mon Sep 17 00:00:00 2001
From: Saxon <saxon@ausocean.org>
Date: Mon, 16 Sep 2019 22:07:57 +0930
Subject: [PATCH] codec/h264/h264dec: simplified logic where there are things
 applicable to non-IDRs, which we don't handle yet.

---
 codec/h264/h264dec/decode.go | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/codec/h264/h264dec/decode.go b/codec/h264/h264dec/decode.go
index bd686efc..ac4ee928 100644
--- a/codec/h264/h264dec/decode.go
+++ b/codec/h264/h264dec/decode.go
@@ -122,12 +122,12 @@ func decodePicOrderCntType1(vid *VideoStream, ctx *SliceContext) (topFieldOrderC
 	// TODO: this will be prevFrameNum when we do frames other than IDR.
 	_ = vid.priorPic.FrameNum
 
-	if vid.idrPicFlag {
-		vid.frameNumOffset = 0
-	} else {
+	if !vid.idrPicFlag {
 		panic("not implemented")
 	}
 
+	vid.frameNumOffset = 0
+
 	absFrameNum := 0
 	if ctx.NumRefFramesInPicOrderCntCycle != 0 {
 		absFrameNum = vid.frameNumOffset + ctx.FrameNum
@@ -172,18 +172,13 @@ func decodePicOrderCntType2(vid *VideoStream, ctx *SliceContext) (topFieldOrderC
 	// TODO: this will be prevFrameNum when we do frames other than IDR.
 	_ = vid.priorPic.FrameNum
 
-	if vid.idrPicFlag {
-		vid.frameNumOffset = 0
-	} else {
+	if !vid.idrPicFlag {
 		panic("not implemented")
 	}
+	vid.frameNumOffset = 0
 
-	tempPicOrderCnt := 2 * (vid.frameNumOffset + ctx.FrameNum)
-	if vid.idrPicFlag {
-		tempPicOrderCnt = 0
-	} else if ctx.RefIdc == 0 {
-		tempPicOrderCnt = 2*(vid.frameNumOffset+ctx.FrameNum) - 1
-	}
+	// TODO: handle tempPicOrderCnt calculation for when not IDR.
+	var tempPicOrderCnt int
 
 	if !ctx.FieldPic {
 		topFieldOrderCnt = tempPicOrderCnt