From eb5cdb32b1c7df6504b3339a83fcbd7849983096 Mon Sep 17 00:00:00 2001
From: Thulinma <jaron@vietors.com>
Date: Fri, 2 Sep 2016 14:43:33 +0200
Subject: [PATCH] Added more H264 SPS decoding

---
 lib/h264.cpp | 61 ++++++++++++++++++++++++++++++++++++----------------
 lib/h264.h   |  7 ++++++
 2 files changed, 49 insertions(+), 19 deletions(-)

diff --git a/lib/h264.cpp b/lib/h264.cpp
index 79101e05..97bd6320 100644
--- a/lib/h264.cpp
+++ b/lib/h264.cpp
@@ -88,15 +88,27 @@ namespace h264 {
     dataLen = Bit::btohs(dtscInit.data() + 6);
   }
 
+  void skipScalingList(Utils::bitstream & bs, size_t listSize){
+    size_t lastScale = 8;
+    size_t nextScale = 8;
+    for (size_t i = 0; i < listSize; i++){
+      if (nextScale){
+        uint64_t deltaScale = bs.getExpGolomb();
+        nextScale = (lastScale + deltaScale + 256) % 256;
+      }
+      lastScale = (nextScale ? nextScale : lastScale);
+    }
+  }
+
   SPSMeta sequenceParameterSet::getCharacteristics()  const {
     SPSMeta result;
+    result.sep_col_plane = false;
 
     //For calculating width
     unsigned int widthInMbs = 0;
     unsigned int cropHorizontal = 0;
 
     //For calculating height
-    bool mbsOnlyFlag = 0;
     unsigned int heightInMapUnits = 0;
     unsigned int cropVertical = 0;
 
@@ -121,33 +133,44 @@ namespace h264 {
     bs.getUExpGolomb();
     if (profileIdc == 100 || profileIdc == 110 || profileIdc == 122 || profileIdc == 244 || profileIdc == 44 || profileIdc == 83 || profileIdc == 86 || profileIdc == 118 || profileIdc == 128) {
       //chroma format idc
-      if (bs.getUExpGolomb() == 3) {
-        bs.skip(1);
+      char chromaFormatIdc = bs.getUExpGolomb();
+      if (chromaFormatIdc == 3) {
+        result.sep_col_plane = (bs.get(1) == 1);
       }
-      bs.getUExpGolomb();
-      bs.getUExpGolomb();
-      bs.skip(1);
-      if (bs.get(1)) {
-        DEBUG_MSG(DLVL_DEVEL, "Scaling matrix not implemented yet");
+      bs.getUExpGolomb();//luma
+      bs.getUExpGolomb();//chroma
+      bs.skip(1);//transform bypass
+      if (bs.get(1)) {//Scaling matrix is present
+        char listSize = (chromaFormatIdc == 3 ? 12 : 8);
+        for (size_t i = 0; i < listSize; i++){
+          bool thisListPresent = bs.get(1);
+          if (thisListPresent){
+            if (i < 6){
+              skipScalingList(bs, 16);
+            }else{
+              skipScalingList(bs, 64);
+            }
+          }
+        }
       }
     }
-    bs.getUExpGolomb();
-    unsigned int pic_order_cnt_type = bs.getUExpGolomb();
-    if (!pic_order_cnt_type) {
-      bs.getUExpGolomb();
-    } else if (pic_order_cnt_type == 1) {
+    result.log2_max_frame_num = bs.getUExpGolomb() + 4;
+    result.cnt_type = bs.getUExpGolomb();
+    if (!result.cnt_type) {
+      result.log2_max_order_cnt = bs.getUExpGolomb() + 4;
+    } else if (result.cnt_type == 1) {
       DEBUG_MSG(DLVL_DEVEL, "This part of the implementation is incomplete(2), to be continued. If this message is shown, contact developers immediately.");
     }
-    bs.getUExpGolomb();
-    bs.skip(1);
-    //Stop skipping data and start doing usefull stuff
+    result.max_ref_frames = bs.getUExpGolomb();//max_num_ref_frames
+    result.gaps = (bs.get(1) == 1);//gaps in frame num allowed
+    //Stop skipping data and start doing useful stuff
 
 
     widthInMbs = bs.getUExpGolomb() + 1;
     heightInMapUnits = bs.getUExpGolomb() + 1;
 
-    mbsOnlyFlag = bs.get(1);//Gets used in height calculation
-    if (!mbsOnlyFlag) {
+    result.mbs_only = (bs.get(1) == 1);//Gets used in height calculation
+    if (!result.mbs_only) {
       bs.skip(1);
     }
     bs.skip(1);
@@ -191,7 +214,7 @@ namespace h264 {
     }
 
     result.width = (widthInMbs * 16) - (cropHorizontal * 2);
-    result.height = ((mbsOnlyFlag ? 1 : 2) * heightInMapUnits * 16) - (cropVertical * 2);
+    result.height = ((result.mbs_only ? 1 : 2) * heightInMapUnits * 16) - (cropVertical * 2);
     return result;
   }
 
diff --git a/lib/h264.h b/lib/h264.h
index 48fcfcc9..0afd0540 100644
--- a/lib/h264.h
+++ b/lib/h264.h
@@ -14,6 +14,13 @@ namespace h264 {
     double fps;
     uint8_t profile;
     uint8_t level;
+    bool sep_col_plane;
+    uint8_t cnt_type;
+    bool gaps;///< Gaps in frame num allowed flag
+    bool mbs_only;///<MBS only flag
+    uint16_t log2_max_frame_num;
+    uint16_t log2_max_order_cnt;
+    uint16_t max_ref_frames;///<Maximum number of reference frames
   };
 
   ///Class for analyzing generic nal units