refactor: enhance Dockerfile and Makefile for platform-specific Tenso…

…rFlow Lite support

- Removed the precompiled TensorFlow Lite C library download step from the Dockerfile, streamlining the build process.
- Updated the Dockerfile to set the TFLITE_LIB_DIR based on the architecture, improving compatibility for linux/arm64 and linux/amd64.
- Modified the Makefile to define TFLITE_LIB_DIR conditionally based on the architecture, ensuring correct library paths for both x86_64 and aarch64 targets.
- Improved clarity and maintainability of both files by explicitly handling platform-specific configurations.

Dockerfile

@@ -30,12 +30,6 @@ COPY --chown=dev-user ./reset_auth.sh ./
 # Download TensorFlow headers
 RUN make check-tensorflow
 
-# Download and configure precompiled TensorFlow Lite C library
-RUN PLATFORM=$(echo ${TARGETPLATFORM} | tr '/' '_') && \
-    echo "Building for platform: ${TARGETPLATFORM}" && \
-    echo "Using library archive: tflite_c_v${TENSORFLOW_VERSION}_${PLATFORM}.tar.gz" && \
-    make download-tflite TARGET=${PLATFORM}
-
 FROM --platform=$TARGETPLATFORM buildenv AS build
 WORKDIR /home/dev-user/src/BirdNET-Go
 
@@ -64,8 +58,18 @@ RUN apt-get update && apt-get install -y --no-install-recommends \
     sox \
     && rm -rf /var/lib/apt/lists/*
 
+# Set TFLITE_LIB_DIR based on architecture
+ARG TARGETPLATFORM
 ARG TFLITE_LIB_DIR
-COPY --from=build ${TFLITE_LIB_DIR}/libtensorflowlite_c.so ${TFLITE_LIB_DIR}
+RUN if [ "$TARGETPLATFORM" = "linux/arm64" ]; then \
+        export TFLITE_LIB_DIR=/usr/aarch64-linux-gnu/lib; \
+    else \
+        export TFLITE_LIB_DIR=/usr/lib; \
+    fi && \
+    echo "Using TFLITE_LIB_DIR=$TFLITE_LIB_DIR"
+
+# Use the TFLITE_LIB_DIR for the library copy
+COPY --from=build ${TFLITE_LIB_DIR}/libtensorflowlite_c.so ${TFLITE_LIB_DIR}/
 RUN ldconfig
 
 # Include reset_auth tool from build stage

Makefile

@@ -73,8 +73,13 @@ $(strip \
 endef
 
 ifeq ($(UNAME_S),Linux)
-    NATIVE_TARGET := linux_$(if $(filter x86_64,$(UNAME_M)),amd64,arm64)
-    TFLITE_LIB_DIR := /usr/lib
+    ifeq ($(UNAME_M),x86_64)
+        NATIVE_TARGET := linux_amd64
+        TFLITE_LIB_DIR := /usr/lib
+    else ifeq ($(UNAME_M),aarch64)
+        NATIVE_TARGET := linux_arm64
+        TFLITE_LIB_DIR := /usr/aarch64-linux-gnu/lib
+    endif
     TFLITE_LIB_EXT := .so
 else ifeq ($(UNAME_S),Darwin)
     NATIVE_TARGET := darwin_$(if $(filter x86_64,$(UNAME_M)),amd64,arm64)
@@ -123,16 +128,20 @@ check-tensorflow:
 define ensure_tflite_symlinks
 	@if [ "$(suffix $(2))" = ".dll" ] && [ ! -f "$(1)/tensorflowlite_c.dll" ]; then \
 		echo "Creating symbolic link for Windows DLL..."; \
+		echo "Linking $(2) to tensorflowlite_c.dll"; \
 		sudo ln -sf "$(1)/tensorflowlite_c-$(patsubst v%,%,$(TFLITE_VERSION)).dll" "$(1)/tensorflowlite_c.dll"; \
 	elif [ "$(UNAME_S)" = "Linux" ] && [ ! -f "$(1)/libtensorflowlite_c.so" ]; then \
 		echo "Creating symbolic links for Linux library..."; \
 		cd $(1) && \
+		echo "Linking $(2) to libtensorflowlite_c.so.2"; \
 		sudo ln -sf $(2) libtensorflowlite_c.so.2 && \
+		echo "Linking libtensorflowlite_c.so.2 to libtensorflowlite_c.so"; \
 		sudo ln -sf libtensorflowlite_c.so.2 libtensorflowlite_c.so && \
 		sudo ldconfig; \
 	elif [ "$(UNAME_S)" = "Darwin" ] && [ ! -f "$(1)/libtensorflowlite_c.dylib" ]; then \
 		echo "Creating symbolic links for macOS library..."; \
 		cd $(1) && \
+		echo "Linking $(2) to libtensorflowlite_c.dylib"; \
 		ln -sf $(2) libtensorflowlite_c.dylib; \
 	fi
 endef