added media format MPEG-4 Timed Text

mediaformat.cpp

@@ -188,6 +188,7 @@ const char *MediaFormat::name() const
         case Mpeg4FineGranularityScalableProfile5: return "MPEG-4 Fine Granularity Scalable Profile L5";
         default: return "MPEG-4 Visual";
         }
+    case GeneralMediaFormat::Mpeg4TimedText: return "MPEG-4 Timed Text";
     case GeneralMediaFormat::Mpc: return "Musepack SV8";
     case GeneralMediaFormat::Pcm:
         switch(sub) {

mediaformat.h

@@ -12,11 +12,11 @@ namespace Media {
  */
 enum class MediaType
 {
-    Unknown,
-    Audio,
-    Video,
-    Text,
-    Hint
+    Unknown, /**< the type is unknown */
+    Audio, /**< audio/sound */
+    Video, /**< video */
+    Text, /**< text/subtitle */
+    Hint /**< hint */
 };
 
 /*!
@@ -24,7 +24,7 @@ enum class MediaType
  */
 enum class GeneralMediaFormat
 {
-    Unknown,
+    Unknown, /**< the format is unknown */
     Aac, /**< Advanced Video Coding */
     Ac3, /**< Dolby Digital */
     Ac4, /**< AC-4 */
@@ -50,16 +50,17 @@ enum class GeneralMediaFormat
     InteractionStream, /**< Interaction Stream */
     Jpeg, /**< JPEG */
     OggKate, /**< Karaoke And Text Encapsulation */
-    Opus = 64, /**< Opus */
-    MicrosoftAudioCodecManager = 26, /**< Microsoft Audio Codec Manager (ACM) */
+    Opus, /**< Opus */
+    MicrosoftAudioCodecManager, /**< Microsoft Audio Codec Manager (ACM) */
     MicrosoftMpeg4, /**< Microsoft MPEG-4 */
     MicrosoftVideoCodecManager, /**< Microsoft Video Codec Manager (VCM) */
     DolbyMlp, /** < Dolby MLP */
     Mpeg1Audio, /**< MPEG-1 Audio */
     Mpeg1Video, /**< MPEG-1 Vudio */
     Mpeg2Audio, /**< MPEG-2 Audio */
-    Mpeg2Video, /**< MPEG-2 Vudio */
-    Mpeg4Video, /**< MPEG-4 */
+    Mpeg2Video, /**< MPEG-2 Video */
+    Mpeg4Video, /**< MPEG-4 Video */
+    Mpeg4TimedText, /**< MPEG-4 Timed Text / Streaming text format / Part 17 */
     Mpc, /**< Musepack */
     Pcm, /**< Pulse Code Modulation */
     Png, /**< PNG */

mp4/mp4ids.cpp

@@ -51,6 +51,8 @@ MediaFormat fourccToMediaFormat(uint32 fourccId)
         return GeneralMediaFormat::Mpeg2Video;
     case Mpeg4Video:
         return GeneralMediaFormat::Mpeg4Video;
+    case Mpeg4TimedText:
+        return GeneralMediaFormat::Mpeg4TimedText;
     case Hevc1: case Hevc2:
         return MediaFormat(GeneralMediaFormat::Hevc);
     case Avc1: case Avc2: case Avc3: case Avc4: case H264Decoder1: case H264Decoder2:

mp4/mp4ids.h

@@ -318,6 +318,7 @@ enum KnownValue : uint32 {
     Mpeg4Decoder2 = 0x53454447,
     Mpeg4Decoder3 = 0x57563146,
     Mpeg4Sample = 0x6d703473, /**< MPEG-4 stream (other then video/audio) */
+    Mpeg4TimedText = 0x74783367, /**< MPEG-4 Timed Text / Streaming text format / Part 17 */
     Mpeg4Video = 0x6d703476, /**< MPEG-4 video */
     MsMpeg4V1Decoder1 = 0x44495631,
     MsMpeg4V1Decoder2 = 0x64697631,

mp4/mp4track.cpp

@@ -1265,23 +1265,28 @@ void Mp4Track::internalParseHeader()
     buff[2] = ((rawLanguage & 0x001F) >> 0x0) + 0x60;
     m_language = string(buff, 3);
     // read hdlr atom
-    //  track type
-    m_istream->seekg(m_hdlrAtom->startOffset() + 16); // seek to beg, skip size, name, version, flags and reserved bytes
-    string trackTypeStr = reader.readString(4);
-    if(trackTypeStr == "soun") {
-        m_mediaType = MediaType::Audio;
-    } else if(trackTypeStr == "vide") {
+    // -> seek to begin skipping size, name, version, flags and reserved bytes
+    m_istream->seekg(m_hdlrAtom->dataOffset() + 8);
+    // -> track type
+    switch(reader.readUInt32BE()) {
+    case 0x76696465:
         m_mediaType = MediaType::Video;
-    } else if(trackTypeStr == "hint") {
+        break;
+    case 0x736F756E:
+        m_mediaType = MediaType::Audio;
+        break;
+    case 0x68696E74:
         m_mediaType = MediaType::Hint;
-    } else if(trackTypeStr == "meta") {
+        break;
+    case 0x6D657461: case 0x74657874:
         m_mediaType = MediaType::Text;
-    } else {
+        break;
+    default:
         m_mediaType = MediaType::Unknown;
     }
+
     //  name
     m_istream->seekg(12, ios_base::cur); // skip reserved bytes
-    //name = reader.readString(hdlrAtom->size - 16 - 4 - 12);
     m_name = reader.readTerminatedString(m_hdlrAtom->totalSize() - 12 - 4 - 12, 0);
     // read stco atom (only chunk count)
     m_chunkOffsetSize = (m_stcoAtom->id() == Mp4AtomIds::ChunkOffset64) ? 8 : 4;