From 0a2a7495666f7d12dc5624a8ff2d86eee92545a1 Mon Sep 17 00:00:00 2001
From: Thulinma <jaron@vietors.com>
Date: Mon, 18 Jul 2016 10:38:26 +0200
Subject: [PATCH] Language support for MP4

---
 lib/mp4_generic.cpp                   | 35 ++++++++++++++++++++++-----
 lib/mp4_generic.h                     |  5 ++--
 src/output/output_progressive_mp4.cpp |  1 +
 3 files changed, 33 insertions(+), 8 deletions(-)

diff --git a/lib/mp4_generic.cpp b/lib/mp4_generic.cpp
index 0c9c8591..8c67fe61 100644
--- a/lib/mp4_generic.cpp
+++ b/lib/mp4_generic.cpp
@@ -2241,20 +2241,43 @@ namespace MP4 {
 
   void MDHD::setLanguage(uint16_t newLanguage) {
     if (getVersion() == 0) {
-      setInt16(newLanguage & 0x7F, 20);
+      setInt16(newLanguage & 0x7FFF, 20);
     } else {
-      setInt16(newLanguage & 0x7F, 32);
+      setInt16(newLanguage & 0x7FFF, 32);
     }
   }
 
-  uint16_t MDHD::getLanguage() {
+  uint16_t MDHD::getLanguageInt() {
     if (getVersion() == 0) {
-      return getInt16(20) & 0x7F;
+      return getInt16(20) & 0x7FFF;
     } else {
-      return getInt16(32) & 0x7F;
+      return getInt16(32) & 0x7FFF;
     }
   }
 
+  void MDHD::setLanguage(const std::string & newLanguage) {
+    if (newLanguage.size() != 3){
+      setLanguage("und");
+      return;
+    }
+    uint16_t newLang = 0;
+    newLang += (newLanguage[0] - 0x60) & 0x1F;
+    newLang <<= 5;
+    newLang += (newLanguage[1] - 0x60) & 0x1F;
+    newLang <<= 5;
+    newLang += (newLanguage[2] - 0x60) & 0x1F;
+    setLanguage(newLang);
+  }
+
+  std::string MDHD::getLanguage() {
+    uint16_t lInt = getLanguageInt();
+    std::string ret;
+    ret += (char)(((lInt & 0x7C00) >> 10) + 0x60);
+    ret += (char)(((lInt & 0x3E0) >> 5) + 0x60);
+    ret += (char)((lInt & 0x1F) + 0x60);
+    return ret;
+  }
+
   std::string MDHD::toPrettyString(uint32_t indent) {
     std::stringstream r;
     r << std::string(indent, ' ') << "[mdhd] Media Header Box (" << boxedSize() << ")" << std::endl;
@@ -2263,7 +2286,7 @@ namespace MP4 {
     r << std::string(indent + 1, ' ') << "ModificationTime: " << getModificationTime() << std::endl;
     r << std::string(indent + 1, ' ') << "TimeScale: " << getTimeScale() << std::endl;
     r << std::string(indent + 1, ' ') << "Duration: " << getDuration() << std::endl;
-    r << std::string(indent + 1, ' ') << "Language: 0x" << std::hex << getLanguage() << std::dec << std::endl;
+    r << std::string(indent + 1, ' ') << "Language: " << getLanguage() << std::endl;
     return r.str();
   }
 
diff --git a/lib/mp4_generic.h b/lib/mp4_generic.h
index 1f760f5e..82c798b7 100644
--- a/lib/mp4_generic.h
+++ b/lib/mp4_generic.h
@@ -463,9 +463,10 @@ namespace MP4 {
       uint32_t getTimeScale();
       void setDuration(uint64_t newDuration);
       uint64_t getDuration();
-      ///\todo return language properly
       void setLanguage(uint16_t newLanguage);
-      uint16_t getLanguage();
+      uint16_t getLanguageInt();
+      void setLanguage(const std::string & newLanguage);
+      std::string getLanguage();
       std::string toPrettyString(uint32_t indent = 0);
   };
 
diff --git a/src/output/output_progressive_mp4.cpp b/src/output/output_progressive_mp4.cpp
index b3652cc5..60af00ed 100644
--- a/src/output/output_progressive_mp4.cpp
+++ b/src/output/output_progressive_mp4.cpp
@@ -70,6 +70,7 @@ namespace Mist {
           unsigned int mdiaOffset = 0;
           {
             MP4::MDHD mdhdBox(thisTrack.lastms - thisTrack.firstms);
+            mdhdBox.setLanguage(thisTrack.lang);
             mdiaBox.setContent(mdhdBox, mdiaOffset++);
           }//MDHD box
           {