[ACR-436] Modify getter API return value from "Unknown" to empty string("")

Change-Id: I38ea8673e735bd4ededd046235cf2dea73da5e0b
Signed-off-by: Minje Ahn <minje.ahn@samsung.com>

diff --git a/include/media_audio.h b/include/media_audio.h
index 391fac5..2536798 100755 (executable)
--- a/include/media_audio.h
+++ b/include/media_audio.h
@@ -103,7 +103,8 @@ int audio_meta_get_media_id(audio_meta_h audio, char **media_id);
 
 /**
  * @brief Gets the album of the given audio metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no album info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -124,7 +125,8 @@ int audio_meta_get_album(audio_meta_h audio, char **album);
 
 /**
  * @brief Gets the artist of the given audio metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no artist info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -145,7 +147,8 @@ int audio_meta_get_artist(audio_meta_h audio, char **artist);
 
 /**
  * @brief Gets the album artist of the given audio metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no album artist info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -166,7 +169,8 @@ int audio_meta_get_album_artist(audio_meta_h audio, char **album_artist);
 
 /**
  * @brief Gets the genre of the given audio metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no genre info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -187,7 +191,8 @@ int audio_meta_get_genre(audio_meta_h audio, char **genre);
 
 /**
  * @brief Gets the composer of the given audio metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no composer info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -208,7 +213,8 @@ int audio_meta_get_composer(audio_meta_h audio, char **composer);
 
 /**
  * @brief Gets the year of the given audio metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no year info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -248,6 +254,8 @@ int audio_meta_get_recorded_date(audio_meta_h audio, char **recorded_date);
 
 /**
  * @brief Gets the copyright notice of the given audio metadata.
+ * @details If the media content has no copyright info, the method returns empty string.
+ *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
  * @remarks You must release @a copyright using free().
@@ -267,7 +275,8 @@ int audio_meta_get_copyright(audio_meta_h audio, char **copyright);
 
 /**
  * @brief Gets the track number of the given audio metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no track info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *

diff --git a/include/media_info.h b/include/media_info.h
index 80b6860..3b0bbe1 100755 (executable)
--- a/include/media_info.h
+++ b/include/media_info.h
@@ -729,6 +729,8 @@ int media_info_get_thumbnail_path(media_info_h media, char **path);
 
 /**
  * @brief Gets the description of media info.
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media info has no description, the method returns empty string.
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
  * @remarks You must release @a description using free().
@@ -903,6 +905,9 @@ int media_info_get_content_name(media_info_h media, char **content_name);
 
 /**
  * @brief Gets the title of media info.
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media info has no title, the method returns empty string.
+ *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
  * @remarks You must release @a title using free().

diff --git a/include/media_video.h b/include/media_video.h
index 765555d..b095d1c 100755 (executable)
--- a/include/media_video.h
+++ b/include/media_video.h
@@ -103,7 +103,8 @@ int video_meta_get_media_id(video_meta_h video, char **media_id);
 
 /**
  * @brief Gets the album of the given video metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no album info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -124,7 +125,8 @@ int video_meta_get_album(video_meta_h video, char **album);
 
 /**
  * @brief Gets the artist of the given video metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no artist info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -145,7 +147,8 @@ int video_meta_get_artist(video_meta_h video, char **artist);
 
 /**
  * @brief Gets the video album artist.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no album artist info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -166,7 +169,8 @@ int video_meta_get_album_artist(video_meta_h video, char **album_artist);
 
 /**
  * @brief Gets the genre of the given video metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no genre info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -187,7 +191,8 @@ int video_meta_get_genre(video_meta_h video, char **genre);
 
 /**
  * @brief Gets the composer of the given video metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no composer info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -208,7 +213,8 @@ int video_meta_get_composer(video_meta_h video, char **composer);
 
 /**
  * @brief Gets the year of the given video metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no year info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
@@ -248,6 +254,9 @@ int video_meta_get_recorded_date(video_meta_h video, char **recorded_date);
 
 /**
  * @brief Gets the copyright notice of the given video metadata.
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no copyright info, the method returns empty string.
+ *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *
  * @remarks You must release @a copyright using free().
@@ -267,7 +276,8 @@ int video_meta_get_copyright(video_meta_h video, char **copyright);
 
 /**
  * @brief Gets the track number of the given videoo metadata.
- * @details If the value is an empty string, the method returns "Unknown".
+ * @details If the value is an empty string, the method returns "Unknown". \n
+ *                Since 3.0, if the media content has no track info, the method returns empty string.
  *
  * @since_tizen @if MOBILE 2.3 @elseif WEARABLE 2.3.1 @endif
  *