IVGCVSW-5571 Expose the TfLite Delegate to the TfLite python API

 * Implemented external delegate adaptor interface for TfLite
 * Activated armnn logging for delegate
 * Added logging info to indicate if gpu tuning is turned on
 * Added pytests to ensure functionality of the external delegate adaptor
 * Included the delegate directory into doxygen
 * Added documentation on how to use the external delegate in python

Signed-off-by: Finn Williams <Finn.Williams@arm.com>
Signed-off-by: Jan Eilers <jan.eilers@arm.com>
Change-Id: Id3b4588fb0b9ac7e3f47ba2c19feead7beb58e18

1 files changed, 39 insertions, 0 deletions

diff --git a/include/armnn/Logging.hpp b/include/armnn/Logging.hpp
index 27971c56e4..9a60e07c63 100644
--- a/include/armnn/Logging.hpp
+++ b/include/armnn/Logging.hpp
@@ -7,6 +7,7 @@
 
 #include <armnn/Utils.hpp>
 #include <iostream>
+#include <algorithm>
 
 namespace armnn
 {
@@ -32,6 +33,44 @@ inline std::string LevelToString(LogSeverity level)
     }
 }
 
+inline LogSeverity StringToLogLevel(std::string level)
+{
+    // Transfer to lower case
+    std::transform(level.begin(), level.end(), level.begin(),
+                   [](unsigned char c){ return std::tolower(c); }
+    );
+
+    if (level == "trace")
+    {
+        return LogSeverity::Trace;
+    }
+    else if (level == "debug")
+    {
+        return LogSeverity::Debug;
+    }
+    else if (level == "info")
+    {
+        return LogSeverity::Info;
+    }
+    else if (level == "warning")
+    {
+        return LogSeverity::Warning;
+    }
+    else if (level == "error")
+    {
+        return LogSeverity::Error;
+    }
+    else if (level == "fatal")
+    {
+        return LogSeverity::Fatal;
+    }
+    else
+    {
+        throw armnn::Exception("Unknown severity level for logging: '" + level +
+                               "'. Valid options: trace, debug, info, warning, error, fatal");
+    }
+}
+
 class LogSink
 {
 public: