rework of aspectRatio calculation for all video formats and rework th…

…e decoding of asf tags

include/exiv2/asfvideo.hpp

@@ -33,7 +33,8 @@ class EXIV2API AsfVideo : public Image {
         auto-pointer. Callers should not continue to use the BasicIo
         instance after it is passed to this method. Use the Image::io()
         method to get a temporary reference.
-   */
+  */
+
   explicit AsfVideo(BasicIo::UniquePtr io);
   //@}
 
@@ -47,6 +48,41 @@ class EXIV2API AsfVideo : public Image {
   //@{
   [[nodiscard]] std::string mimeType() const override;
   //@}
+
+  /* @class GUID_struct
+   *
+   * @brief A class to represent a globally unique identifier (GUID) structure
+   *
+   * This class represents a globally unique identifier (GUID) structure which is used to identify objects in a
+   * distributed environment. A GUID is a unique identifier that is generated on a computer and can be used to
+   * identify an object across different systems. The GUID structure is comprised of four 32-bit values and an
+   * array of 8 bytes.
+   *
+   * @note The byte order of the GUID structure is in little endian.
+   *
+   * @see https://en.wikipedia.org/wiki/Globally_unique_identifier
+   *
+   */
+  class GUIDTag {
+    uint32_t data1_;
+    uint16_t data2_;
+    uint16_t data3_;
+    std::array<byte, 8> data4_;
+
+   public:
+    bool operator==(const GUIDTag& other) const;
+
+    // Constructor to create a GUID object by passing individual values for each attribute
+    GUIDTag(unsigned int data1, unsigned short data2, unsigned short data3, std::array<byte, 8> data4);
+
+    // Constructor to create a GUID object from a byte array
+    GUIDTag(const uint8_t* bytes);
+
+    std::string to_string();
+
+    bool operator<(const GUIDTag& other) const;
+  };
+
  private:
   static constexpr size_t CODEC_TYPE_VIDEO = 1;
   static constexpr size_t CODEC_TYPE_AUDIO = 2;
@@ -78,6 +114,8 @@ class EXIV2API AsfVideo : public Image {
     position. Calls tagDecoder() or skips to next tag, if required.
    */
   void decodeBlock();
+
+  void decodeHeader();
   /*!
     @brief Interpret File_Properties tag information, and save it in
         the respective XMP container.
@@ -118,12 +156,6 @@ class EXIV2API AsfVideo : public Image {
 
   void DegradableJPEGMedia();
 
-  /*!
-    @brief Calculates Aspect Ratio of a video, and stores it in the
-        respective XMP container.
-   */
-  void aspectRatio();
-
  private:
   //! Variable to store height and width of a video frame.
   uint64_t height_, width_;

include/exiv2/matroskavideo.hpp

@@ -158,11 +158,6 @@ class EXIV2API MatroskaVideo : public Image {
   void decodeBooleanTags(const Internal::MatroskaTag* tag, const byte* buf, size_t size);
   void decodeDateTags(const Internal::MatroskaTag* tag, const byte* buf, size_t size);
   void decodeFloatTags(const Internal::MatroskaTag* tag, const byte* buf, size_t size);
-  /*!Internal::
-    @brief Calculates Aspect Ratio of a video, and stores it in the
-        respective XMP container.
-   */
-  void aspectRatio();
 
  private:
   //! Variable to check the end of metadata traversing.

include/exiv2/quicktimevideo.hpp

@@ -192,11 +192,6 @@ class EXIV2API QuickTimeVideo : public Image {
     @param size Size of the data block that is to skipped.
    */
   void discard(size_t size);
-  /*!
-    @brief Calculates Aspect Ratio of a video, and stores it in the
-        respective XMP container.
-   */
-  void aspectRatio();
 
   //! Variable which stores Time Scale unit, used to calculate time.
   uint64_t timeScale_ = 0;

src/helper_functions.cpp

@@ -6,6 +6,7 @@
 #include <codecvt>
 #include <cstring>
 #include <locale>
+#include <numeric>
 #include "enforce.hpp"
 
 std::string string_from_unterminated(const char* data, size_t data_length) {
@@ -17,11 +18,6 @@ std::string string_from_unterminated(const char* data, size_t data_length) {
 }
 
 namespace Exiv2 {
-char returnHex(int n) {
-  if (n >= 0 && n <= 9)
-    return static_cast<char>(n + 48);
-  return static_cast<char>(n + 55);
-}
 
 std::string utf16ToUtf8(const std::wstring& wstr) {
   using convert_typeX = std::codecvt_utf8<wchar_t>;
@@ -65,4 +61,13 @@ std::string readStringTag(BasicIo::UniquePtr& io, size_t length) {
   return Exiv2::toString(FieldBuf.data()).substr(0, length);
 }
 
+std::string getAspectRatio(size_t width, size_t height) {
+  if (height == 0 || width == 0)
+    return std::to_string(width) + ":" + std::to_string(height);
+
+  int ratioWidth = width / std::gcd(width, height);
+  int ratioHeight = height / std::gcd(width, height);
+  return std::to_string(ratioWidth) + ":" + std::to_string(ratioHeight);
+}
+
 }  // namespace Exiv2

src/helper_functions.hpp

@@ -24,13 +24,6 @@
 std::string string_from_unterminated(const char* data, size_t data_length);
 
 namespace Exiv2 {
-/*!
-  @brief Function used to convert a decimal number to its Hexadecimal
-      equivalent, then parsed into a character
-  @param n Integer which is to be parsed as Hexadecimal character
-  @return Return a Hexadecimal number, in character
- */
-char returnHex(int n);
 
 static constexpr size_t BYTE = 0x1;
 static constexpr size_t WCHAR = 0x2;
@@ -60,5 +53,10 @@ std::string utf16ToUtf8(const std::wstring& wstr);
 
 [[nodiscard]] std::string readStringTag(Exiv2::BasicIo::UniquePtr& io, size_t length = DWORD);
 
+/*!
+  @brief Calculates Aspect Ratio of a video
+ */
+[[nodiscard]] std::string getAspectRatio(size_t width, size_t height);
+
 }  // namespace Exiv2
 #endif  // HELPER_FUNCTIONS_HPP

src/matroskavideo.cpp

@@ -24,6 +24,7 @@
 #include "basicio.hpp"
 #include "error.hpp"
 #include "futils.hpp"
+#include "helper_functions.hpp"
 #include "matroskavideo.hpp"
 #include "tags.hpp"
 #include "tags_int.hpp"
@@ -606,7 +607,7 @@ void MatroskaVideo::readMetadata() {
   while (continueTraversing_)
     decodeBlock();
 
-  aspectRatio();
+  xmpData_["Xmp.video.AspectRatio"] = getAspectRatio(width_, height_);
 }
 
 void MatroskaVideo::decodeBlock() {
@@ -888,41 +889,6 @@ void MatroskaVideo::decodeFloatTags(const MatroskaTag* tag, const byte* buf, siz
   }
 }
 
-void MatroskaVideo::aspectRatio() {
-  double aspectRatio = static_cast<double>(width_) / static_cast<double>(height_);
-  aspectRatio = floor(aspectRatio * 10) / 10;
-  xmpData_["Xmp.video.AspectRatio"] = aspectRatio;
-
-  auto aR = static_cast<int>((aspectRatio * 10.0) + 0.1);
-
-  switch (aR) {
-    case 13:
-      xmpData_["Xmp.video.AspectRatio"] = "4:3";
-      break;
-    case 17:
-      xmpData_["Xmp.video.AspectRatio"] = "16:9";
-      break;
-    case 10:
-      xmpData_["Xmp.video.AspectRatio"] = "1:1";
-      break;
-    case 16:
-      xmpData_["Xmp.video.AspectRatio"] = "16:10";
-      break;
-    case 22:
-      xmpData_["Xmp.video.AspectRatio"] = "2.21:1";
-      break;
-    case 23:
-      xmpData_["Xmp.video.AspectRatio"] = "2.35:1";
-      break;
-    case 12:
-      xmpData_["Xmp.video.AspectRatio"] = "5:4";
-      break;
-    default:
-      xmpData_["Xmp.video.AspectRatio"] = aspectRatio;
-      break;
-  }
-}
-
 uint32_t MatroskaVideo::findBlockSize(byte b) {
   if (b & 128)
     return 1;

src/quicktimevideo.cpp

@@ -25,6 +25,7 @@
 #include "enforce.hpp"
 #include "error.hpp"
 #include "futils.hpp"
+#include "helper_functions.hpp"
 #include "quicktimevideo.hpp"
 #include "safe_op.hpp"
 #include "tags.hpp"
@@ -528,7 +529,7 @@ void QuickTimeVideo::readMetadata() {
   while (continueTraversing_)
     decodeBlock();
 
-  aspectRatio();
+  xmpData_["Xmp.video.AspectRatio"] = getAspectRatio(width_, height_);
 }  // QuickTimeVideo::readMetadata
 
 void QuickTimeVideo::decodeBlock(std::string const& entered_from) {
@@ -1536,43 +1537,6 @@ void QuickTimeVideo::movieHeaderDecoder(size_t size) {
   io_->readOrThrow(buf.data(), size % 4);
 }  // QuickTimeVideo::movieHeaderDecoder
 
-void QuickTimeVideo::aspectRatio() {
-  // TODO - Make a better unified method to handle all cases of Aspect Ratio
-
-  double aspectRatio = static_cast<double>(width_) / static_cast<double>(height_);
-  aspectRatio = floor(aspectRatio * 10) / 10;
-  xmpData_["Xmp.video.AspectRatio"] = aspectRatio;
-
-  auto aR = static_cast<int>((aspectRatio * 10.0) + 0.1);
-
-  switch (aR) {
-    case 13:
-      xmpData_["Xmp.video.AspectRatio"] = "4:3";
-      break;
-    case 17:
-      xmpData_["Xmp.video.AspectRatio"] = "16:9";
-      break;
-    case 10:
-      xmpData_["Xmp.video.AspectRatio"] = "1:1";
-      break;
-    case 16:
-      xmpData_["Xmp.video.AspectRatio"] = "16:10";
-      break;
-    case 22:
-      xmpData_["Xmp.video.AspectRatio"] = "2.21:1";
-      break;
-    case 23:
-      xmpData_["Xmp.video.AspectRatio"] = "2.35:1";
-      break;
-    case 12:
-      xmpData_["Xmp.video.AspectRatio"] = "5:4";
-      break;
-    default:
-      xmpData_["Xmp.video.AspectRatio"] = aspectRatio;
-      break;
-  }
-}  // QuickTimeVideo::aspectRatio
-
 Image::UniquePtr newQTimeInstance(BasicIo::UniquePtr io, bool /*create*/) {
   auto image = std::make_unique<QuickTimeVideo>(std::move(io));
   if (!image->good()) {

src/riffvideo.cpp

@@ -517,7 +517,8 @@ void RiffVideo::readAviHeader() {
   io_->seekOrThrow(io_->tell() + DWORD * 4, BasicIo::beg,
                    ErrorCode::kerFailedToReadImageData);  // TimeScale, DataRate, StartTime, DataLength
 
-  fillAspectRatio(width, height);
+  xmpData_["Xmp.video.AspectRatio"] = getAspectRatio(width, height);
+
   fillDuration(frame_rate, frame_count);
 }
 
@@ -758,44 +759,6 @@ void RiffVideo::fillDuration(double frame_rate, size_t frame_count) {
   xmpData_["Xmp.video.Duration"] = duration;  // Duration in number of seconds
 }  // RiffVideo::fillDuration
 
-void RiffVideo::fillAspectRatio(size_t width, size_t height) {
-  if (height == 0)
-    return;
-  double aspectRatio = static_cast<double>(width) / height;
-  aspectRatio = floor(aspectRatio * 10) / 10;
-  xmpData_["Xmp.video.AspectRatio"] = aspectRatio;
-
-  auto aR = static_cast<int>((aspectRatio * 10.0) + 0.1);
-
-  switch (aR) {
-    case 13:
-      xmpData_["Xmp.video.AspectRatio"] = "4:3";
-      break;
-    case 17:
-      xmpData_["Xmp.video.AspectRatio"] = "16:9";
-      break;
-    case 10:
-      xmpData_["Xmp.video.AspectRatio"] = "1:1";
-      break;
-    case 16:
-      xmpData_["Xmp.video.AspectRatio"] = "16:10";
-      break;
-    case 22:
-      xmpData_["Xmp.video.AspectRatio"] = "2.21:1";
-      break;
-    case 23:
-      xmpData_["Xmp.video.AspectRatio"] = "2.35:1";
-      break;
-    case 12:
-      xmpData_["Xmp.video.AspectRatio"] = "5:4";
-      break;
-    default:
-      xmpData_["Xmp.video.AspectRatio"] = aspectRatio;
-
-      break;
-  }
-}
-
 Image::UniquePtr newRiffInstance(BasicIo::UniquePtr io, bool /*create*/) {
   auto image = std::make_unique<RiffVideo>(std::move(io));
   if (!image->good()) {

test/data/test_reference_files/flame.avi.out

@@ -9,7 +9,7 @@ Xmp.audio.ChannelType                        XmpText     4  Mono  Mono
 Xmp.video.StreamCount                        XmpText     4  3074  3074
 Xmp.video.Width                              XmpText     3  256  256
 Xmp.video.Height                             XmpText     3  240  240
-Xmp.video.AspectRatio                        XmpText     3  1:1  1:1
+Xmp.video.AspectRatio                        XmpText     5  16:15  16:15
 Xmp.video.FileDataRate                       XmpText    11  8.78036e-05  8.78036e-05
 Xmp.video.Duration                           XmpText     4  3142  3142
 Xmp.video.Codec                              XmpText     4  cvid  cvid

test/data/test_reference_files/small_video.mp4.out

@@ -64,4 +64,4 @@ Xmp.audio.ChannelType                        XmpText     1  2  2
 Xmp.audio.BitsPerSample                      XmpText     2  16  16
 Xmp.audio.SampleRate                         XmpText     5  44100  44100
 Xmp.audio.HandlerVendorID                    XmpText     5  Apple  Apple
-Xmp.video.AspectRatio                        XmpText     3  0.5  0.5
+Xmp.video.AspectRatio                        XmpText     4  9:16  9:16