added ADTS frame parser

adts/adtsframe.cpp

@@ -0,0 +1,31 @@
+#include "adtsframe.h"
+#include "../exceptions.h"
+
+#include <c++utilities/io/binaryreader.h>
+
+using namespace std;
+using namespace IoUtilities;
+
+namespace Media {
+
+/*!
+ * \class Media::AdtsFrame
+ * \brief The AdtsFrame class is used to parse "Audio Data Transport Stream" frames.
+ */
+
+/*!
+ * \brief Parses the header read using the specified \a reader.
+ * \throws Throws InvalidDataException if the data read from the stream is
+ *         no valid frame header.
+ */
+void AdtsFrame::parseHeader(IoUtilities::BinaryReader &reader)
+{
+    m_header1 = reader.readUInt16BE();
+    if(!isValid()) {
+        throw InvalidDataException();
+    }
+    m_header2 = hasCrc() ? reader.readUInt56BE() : (reader.readUInt40BE() << 2);
+}
+
+} // namespace Media
+

adts/adtsframe.h

@@ -0,0 +1,132 @@
+#ifndef MEDIA_ADTSFRAME_H
+#define MEDIA_ADTSFRAME_H
+
+#include <c++utilities/conversion/types.h>
+#include <c++utilities/application/global.h>
+
+namespace IoUtilities {
+class BinaryReader;
+}
+
+namespace Media {
+
+class LIB_EXPORT AdtsFrame
+{
+public:
+    AdtsFrame();
+
+    void parseHeader(IoUtilities::BinaryReader &reader);
+
+    bool isValid() const;
+    bool isMpeg4() const;
+    bool hasCrc() const;
+    byte mpeg4AudioObjectId() const;
+    byte mpeg4SampleRateIndex() const;
+    byte mpeg4ChannelConfig() const;
+    uint16 length() const;
+    uint16 bufferFullness() const;
+    byte frameCount() const;
+    uint16 crc() const;
+
+private:
+    uint16 m_header1;
+    uint64 m_header2;
+};
+
+/*!
+ * \brief Constructs a new frame.
+ */
+inline AdtsFrame::AdtsFrame() :
+    m_header1(0)
+{}
+
+/*!
+ * \brief Returns an indication whether the frame is valid.
+ */
+inline bool AdtsFrame::isValid() const
+{
+    return (m_header1 & 0xFFF6u) == 0xFFF0u;
+}
+
+/*!
+ * \brief Returns whether the MPEG version is MPEG-4; otherwise the MPEG version is MPEG-2.
+ */
+inline bool AdtsFrame::isMpeg4() const
+{
+    return m_header1 & 0x8u;
+}
+
+/*!
+ * \brief Returns whether a CRC-16 checksum is present.
+ */
+inline bool AdtsFrame::hasCrc() const
+{
+    return m_header1 & 0x1u;
+}
+
+/*!
+ * \brief Returns the MPEG-4 audio object type ID.
+ * \sa Media::Mpeg4AudioObjectIds
+ * \sa Mpeg4AudioObjectIds::idToMediaFormat()
+ */
+inline byte AdtsFrame::mpeg4AudioObjectId() const
+{
+    return (m_header2 >> 0x36) + 0x1u;
+}
+
+/*!
+ * \brief Returns the MPEG-4 sample rate index.
+ * \sa Media::mpeg4SampleRateTable
+ */
+inline byte AdtsFrame::mpeg4SampleRateIndex() const
+{
+    return (m_header2 >> 0x32) & 0xFu;
+}
+
+/*!
+ * \brief Returns the MPEG-4 channel configuration.
+ * \sa Media::Mpeg4ChannelConfigs
+ * \sa Media::mpeg4SampleRateTable::channelConfigString()
+ */
+inline byte AdtsFrame::mpeg4ChannelConfig() const
+{
+    return (m_header2 >> 0x2E) & 0x7u;
+}
+
+/*!
+ * \brief Returns the length of the frame (including the header) in bytes.
+ */
+inline uint16 AdtsFrame::length() const
+{
+    return (m_header2 >> 0x1D) & 0x1FFFu;
+}
+
+/*!
+ * \brief Returns the buffer fullness.
+ */
+inline uint16 AdtsFrame::bufferFullness() const
+{
+    return (m_header2 >> 0x12) & 0x7FFu;
+}
+
+/*!
+ * \brief Returns the number of AAC frames (RDBs) in the ADTS frame.
+ */
+inline byte AdtsFrame::frameCount() const
+{
+    return ((m_header2 >> 0x10) & 0x3u) + 0x1u;
+}
+
+/*!
+ * \brief Returns the CRC-16 checksum of the frame.
+ * \sa hasCrc()
+ */
+inline uint16 AdtsFrame::crc() const
+{
+    return m_header2 & 0xFFFFu;
+}
+
+
+} // namespace Media
+
+#endif // MEDIA_ADTSFRAME_H