diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6e54178..401cc14 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,10 +31,18 @@ set(CMAKE_CXX_STANDARD_REQUIRED ON)
 # External dependencies
 set(EXTERNALPROJECT_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/cmake)
 
+option(USE_SYSTEM_LIBS "Use system-provided libraries" OFF)
+
+option(USE_SYSTEM_ZLIB "Use system-provided ZLib library" OFF)
 include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.zlib.cmake)
+
+option(USE_SYSTEM_YATO "Use system-provided Yato library" OFF)
 include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.yato.cmake)
 
+option(USE_SYSTEM_LIBJPEG "Use system-provided LibJPEG library" OFF)
 option(FREEIMAGE_WITH_LIBJPEG "Compile with the LibJPEG backend" ON)
+option(FREEIMAGE_WITH_LIBJPEG_TRANSFORMS "LibJPEG lossless transforms" ON)
+
 if (FREEIMAGE_WITH_LIBJPEG)
     include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.jpeg.cmake)
 endif()
@@ -44,31 +52,37 @@ if (FREEIMAGE_WITH_LIBOPENJPEG)
     include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.openjpeg.cmake)
 endif()
 
+option(USE_SYSTEM_LIBOPENEXR "Use system-provided OpenEXR library" OFF)
 option(FREEIMAGE_WITH_LIBOPENEXR "Compile with the LibOpenEXR backend" ON)
 if (FREEIMAGE_WITH_LIBOPENEXR)
     include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.openexr.cmake)
 endif()
 
+option(USE_SYSTEM_LIBPNG "Use system-provided LibPNG library" OFF)
 option(FREEIMAGE_WITH_LIBPNG "Compile with the LibPNG backend" ON)
 if (FREEIMAGE_WITH_LIBPNG)
     include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.png.cmake)
 endif()
 
+option(USE_SYSTEM_LIBTIFF "Use system-provided LibTIFF library" OFF)
 option(FREEIMAGE_WITH_LIBTIFF "Compile with the LibTIFF backend" ON)
 if (FREEIMAGE_WITH_LIBTIFF)
     include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.tiff.cmake)
 endif()
 
+option(USE_SYSTEM_LIBWEBP "Use system-provided LibWEBP library" OFF)
 option(FREEIMAGE_WITH_LIBWEBP "Compile with the LibWEBP backend" ON)
 if (FREEIMAGE_WITH_LIBWEBP)
     include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.webp.cmake)
 endif()
 
+option(USE_SYSTEM_LIBRAW "Use system-provided LibRAW library" OFF)
 option(FREEIMAGE_WITH_LIBRAW "Compile with the LibRAW backend" ON)
 if (FREEIMAGE_WITH_LIBRAW)
     include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.raw.cmake)
 endif()
 
+option(USE_SYSTEM_LIBHEIF "Use system-provided LibHEIF library" OFF)
 option(FREEIMAGE_WITH_LIBHEIF "Compile with the LibHEIF backend" ON)
 if (FREEIMAGE_WITH_LIBHEIF)
     include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.heif.cmake)
diff --git a/Source/CMakeLists.txt b/Source/CMakeLists.txt
index 9e3d759..e3c7311 100644
--- a/Source/CMakeLists.txt
+++ b/Source/CMakeLists.txt
@@ -82,6 +82,9 @@ endif()
 
 if (FREEIMAGE_WITH_LIBJPEG)
     target_compile_definitions(FreeImage PUBLIC "-DFREEIMAGE_WITH_LIBJPEG=1")
+    if (FREEIMAGE_WITH_LIBJPEG_TRANSFORMS)
+        target_compile_definitions(FreeImage PUBLIC "-DFREEIMAGE_WITH_LIBJPEG_TRANSFORMS=1")
+    endif()
     target_link_libraries(FreeImage PRIVATE LibJPEG)
     list(APPEND freeimage_plugins Plugins/PluginJPEG.cpp)
 endif()
diff --git a/Source/FreeImage/ZLibInterface.cpp b/Source/FreeImage/ZLibInterface.cpp
index 2938d51..a4f5f72 100644
--- a/Source/FreeImage/ZLibInterface.cpp
+++ b/Source/FreeImage/ZLibInterface.cpp
@@ -22,7 +22,8 @@
 #include "zlib.h"
 #include "FreeImage.h"
 #include "Utilities.h"
-#include "zutil.h"	/* must be the last header because of error C3163 in VS2008 (_vsnprintf defined in stdio.h) */
+
+constexpr uint8_t GZIP_OS_UNKNOWN = 255;
 
 /**
 Compresses a source buffer into a target buffer, using the ZLib library. 
@@ -115,7 +116,7 @@ FreeImage_ZLibGZip(uint8_t *target, uint32_t target_size, uint8_t *source, uint3
 			return 0;
         case Z_OK: {
             // patch header, setup crc and length (stolen from mod_trace_output)
-            uint8_t *p = target + 8; *p++ = 2; *p = OS_CODE; // xflags, os_code
+            uint8_t *p = target + 8; *p++ = 2; *p = GZIP_OS_UNKNOWN; // xflags, os_code
  	        crc = crc32(crc, source, source_size);
 	        memcpy(target + 4 + dest_len, &crc, 4);
 	        memcpy(target + 8 + dest_len, &source_size, 4);
diff --git a/Source/FreeImageToolkit/JPEGTransform.cpp b/Source/FreeImageToolkit/JPEGTransform.cpp
index 97c47ad..22984cc 100644
--- a/Source/FreeImageToolkit/JPEGTransform.cpp
+++ b/Source/FreeImageToolkit/JPEGTransform.cpp
@@ -28,10 +28,15 @@ extern "C" {
 #undef FAR
 #include <setjmp.h>
 
-#include "jinclude.h"
+#include <cstddef>
+#include <cstdio>
 #include "jpeglib.h"
 #include "jerror.h"
+
+#if FREEIMAGE_WITH_LIBJPEG_TRANSFORMS
 #include "transupp.h"
+#endif // FREEIMAGE_WITH_LIBJPEG_TRANSFORMS
+
 }
 
 #endif // FREEIMAGE_WITH_LIBJPEG
@@ -154,6 +159,7 @@ getCropString(char* crop, size_t cropSize, int* left, int* top, int* right, int*
 	return TRUE;
 }
 
+#if FREEIMAGE_WITH_LIBJPEG_TRANSFORMS
 static FIBOOL
 JPEGTransformFromHandle(FreeImageIO* src_io, fi_handle src_handle, FreeImageIO* dst_io, fi_handle dst_handle, FREE_IMAGE_JPEG_OPERATION operation, int* left, int* top, int* right, int* bottom, FIBOOL perfect) {
 	const FIBOOL onlyReturnCropRect = (!dst_io || !dst_handle);
@@ -368,13 +374,14 @@ JPEGTransformFromHandle(FreeImageIO* src_io, fi_handle src_handle, FreeImageIO*
 	return TRUE;
 }
 
-#else // FREEIMAGE_WITH_LIBJPEG
+#else // FREEIMAGE_WITH_LIBJPEG_TRANSFORMS
 
 static FIBOOL
 JPEGTransformFromHandle(FreeImageIO*, fi_handle, FreeImageIO*, fi_handle, FREE_IMAGE_JPEG_OPERATION, int*, int*, int*, int*, FIBOOL) {
 	return FALSE;
 }
 
+#endif // FREEIMAGE_WITH_LIBJPEG_TRANSFORMS
 #endif // FREEIMAGE_WITH_LIBJPEG
 
 // ----------------------------------------------------------
diff --git a/Source/Plugins/PluginJPEG.cpp b/Source/Plugins/PluginJPEG.cpp
index b951fdb..dd5ce4c 100644
--- a/Source/Plugins/PluginJPEG.cpp
+++ b/Source/Plugins/PluginJPEG.cpp
@@ -35,10 +35,10 @@ extern "C" {
 #undef FAR
 #include <setjmp.h>
 
-#include "jinclude.h"
+#include <cstddef>
+#include <cstdio>
 #include "jpeglib.h"
 #include "jerror.h"
-#include "jversion.h"
 #include "jmorecfg.h"
 }
 
@@ -483,119 +483,6 @@ marker_is_icc(jpeg_saved_marker_ptr marker) {
 	return FALSE;
 }
 
-#ifndef JPEG_HAS_READ_ICC_PROFILE
-/**
-  See if there was an ICC profile in the JPEG file being read;
-  if so, reassemble and return the profile data.
-
-  TRUE is returned if an ICC profile was found, FALSE if not.
-  If TRUE is returned, *icc_data_ptr is set to point to the
-  returned data, and *icc_data_len is set to its length.
-  
-  IMPORTANT: the data at **icc_data_ptr has been allocated with malloc()
-  and must be freed by the caller with free() when the caller no longer
-  needs it.  (Alternatively, we could write this routine to use the
-  IJG library's memory allocator, so that the data would be freed implicitly
-  at jpeg_finish_decompress() time.  But it seems likely that many apps
-  will prefer to have the data stick around after decompression finishes.)
-  
-  NOTE: if the file contains invalid ICC APP2 markers, we just silently
-  return FALSE.  You might want to issue an error message instead.
-*/
-static FIBOOL 
-jpeg_read_icc_profile(j_decompress_ptr cinfo, JOCTET **icc_data_ptr, unsigned *icc_data_len) {
-	jpeg_saved_marker_ptr marker;
-	int num_markers = 0;
-	int seq_no;
-	unsigned total_length;
-
-	const int MAX_SEQ_NO = 255;			// sufficient since marker numbers are bytes
-	uint8_t marker_present[MAX_SEQ_NO+1];	// 1 if marker found
-	unsigned data_length[MAX_SEQ_NO+1];	// size of profile data in marker
-	unsigned data_offset[MAX_SEQ_NO+1];	// offset for data in marker
-	
-	*icc_data_ptr = nullptr;		// avoid confusion if FALSE return
-	*icc_data_len = 0;
-
-	/**
-	this first pass over the saved markers discovers whether there are
-	any ICC markers and verifies the consistency of the marker numbering.
-	*/
-
-	memset(marker_present, 0, (MAX_SEQ_NO + 1));
-
-	for (marker = cinfo->marker_list; marker; marker = marker->next) {
-		if (marker_is_icc(marker)) {
-			if (num_markers == 0) {
-				// number of markers
-				num_markers = GETJOCTET(marker->data[13]);
-			}
-			else if (num_markers != GETJOCTET(marker->data[13])) {
-				return FALSE;		// inconsistent num_markers fields 
-			}
-			// sequence number
-			seq_no = GETJOCTET(marker->data[12]);
-			if (seq_no <= 0 || seq_no > num_markers) {
-				return FALSE;		// bogus sequence number 
-			}
-			if (marker_present[seq_no]) {
-				return FALSE;		// duplicate sequence numbers 
-			}
-			marker_present[seq_no] = 1;
-			data_length[seq_no] = marker->data_length - ICC_HEADER_SIZE;
-		}
-	}
-
-	if (num_markers == 0)
-		return FALSE;
-		
-	/**
-	check for missing markers, count total space needed,
-	compute offset of each marker's part of the data.
-	*/
-
-	total_length = 0;
-	for (seq_no = 1; seq_no <= num_markers; seq_no++) {
-		if (marker_present[seq_no] == 0) {
-			return FALSE;		// missing sequence number
-		}
-		data_offset[seq_no] = total_length;
-		total_length += data_length[seq_no];
-	}
-
-    if (total_length <= 0) {
-        return FALSE;		// found only empty markers ?
-    }
-
-	// allocate space for assembled data 
-    std::unique_ptr<JOCTET, decltype(&free)> icc_data(static_cast<JOCTET*>(malloc(total_length * sizeof(JOCTET))), &free);
-    if (!icc_data) {
-        return FALSE;		// out of memory
-    }
-
-	// and fill it in
-	for (marker = cinfo->marker_list; marker; marker = marker->next) {
-		if (marker_is_icc(marker)) {
-			JOCTET FAR *src_ptr;
-			JOCTET *dst_ptr;
-			unsigned length;
-			seq_no = GETJOCTET(marker->data[12]);
-			dst_ptr = icc_data.get() + data_offset[seq_no];
-			src_ptr = marker->data + ICC_HEADER_SIZE;
-			length = data_length[seq_no];
-			while (length--) {
-				*dst_ptr++ = *src_ptr++;
-			}
-		}
-	}
-
-	*icc_data_ptr = icc_data.release();
-	*icc_data_len = total_length;
-
-	return TRUE;
-}
-#endif
-
 /**
 	Read JPEG_APPD marker (IPTC or Adobe Photoshop profile)
 */
diff --git a/Source/Plugins/PluginWebP.cpp b/Source/Plugins/PluginWebP.cpp
index 25f2d98..bb3bdec 100644
--- a/Source/Plugins/PluginWebP.cpp
+++ b/Source/Plugins/PluginWebP.cpp
@@ -27,7 +27,26 @@
 #include "webp/decode.h"
 #include "webp/encode.h"
 #include "webp/mux.h"
-#include "dec/vp8i_dec.h"
+
+#include <cstdio>
+
+struct WebPVersion {
+	uint32_t major;
+	uint32_t minor;
+	uint32_t patch;
+};
+
+static WebPVersion GetWebPVersion() {
+	static char version[32];
+
+	const uint32_t v = WebPGetDecoderVersion();
+
+	return {
+		(v >> 16) & 0xff,
+		(v >> 8) & 0xff,
+		v & 0xff
+	};
+}
 
 // ==========================================================
 // Plugin Interface
@@ -681,11 +700,22 @@ InitWEBP(Plugin *plugin, int format_id) {
 
 
 const FIDEPENDENCY* GetWebpDependencyInfo() {
+	static char fullVersion[32];
+
+	const auto version = GetWebPVersion();
+
+	std::snprintf(fullVersion, sizeof(fullVersion),
+		"LibWebP v%d.%d.%d",
+		version.major,
+		version.minor,
+		version.patch);
+
 	static const FIDEPENDENCY info = {
 		.name = "LibWebP",
-		.fullVersion  = "LibWebP v" FI_QUOTE(DEC_MAJ_VERSION) "." FI_QUOTE(DEC_MIN_VERSION) "." FI_QUOTE(DEC_REV_VERSION),
-		.majorVersion = DEC_MAJ_VERSION,
-		.minorVersion = DEC_MIN_VERSION
+		.fullVersion = fullVersion,
+		.majorVersion = version.major,
+		.minorVersion = version.minor
 	};
+
 	return &info;
 }
diff --git a/cmake/dependency.heif.cmake b/cmake/dependency.heif.cmake
index 0f1af8b..f202daf 100644
--- a/cmake/dependency.heif.cmake
+++ b/cmake/dependency.heif.cmake
@@ -3,6 +3,13 @@
 #
 # Output target: LibHEIF
 
+set(HEIF_VERSION "1.20.2")
+
+if (USE_SYSTEM_LIBHEIF OR USE_SYSTEM_LIBS)
+    find_package(libheif REQUIRED CONFIG)
+    add_library(LibHEIF ALIAS heif)
+    return()
+endif()
 
 include(${EXTERNALPROJECT_INCLUDE_DIR}/external_project_common.cmake)
 include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.de265.cmake)
@@ -10,8 +17,6 @@ include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.kvazaar.cmake)
 include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.dav1d.cmake)
 include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.svtav1.cmake)
 
-set(HEIF_VERSION "1.20.2")
-
 ExternalProject_Add(HEIF
     PREFIX ${EXTERNALPROJECT_BINARY_ROOT}/heif
     URL "https://github.com/strukturag/libheif/releases/download/v${HEIF_VERSION}/libheif-${HEIF_VERSION}.tar.gz"
diff --git a/cmake/dependency.jpeg.cmake b/cmake/dependency.jpeg.cmake
index 129fa4f..13f7646 100644
--- a/cmake/dependency.jpeg.cmake
+++ b/cmake/dependency.jpeg.cmake
@@ -2,6 +2,12 @@
 #
 # Output target: LibJPEG
 
+if (USE_SYSTEM_LIBJPEG OR USE_SYSTEM_LIBS)
+    find_package(JPEG REQUIRED)
+    add_library(LibJPEG ALIAS JPEG::JPEG)
+    return()
+endif()
+
 include(${EXTERNALPROJECT_INCLUDE_DIR}/external_project_common.cmake)
 
 
@@ -71,7 +77,6 @@ elseif(JPEG_REPOSITORY STREQUAL "JPEG-turbo")
     else()
         target_link_libraries(LibJPEG INTERFACE ${INSTALL_DIR}/lib/libturbojpeg${CMAKE_STATIC_LIBRARY_SUFFIX})
     endif()
-    target_compile_options(LibJPEG INTERFACE "-DJPEG_HAS_READ_ICC_PROFILE=1")
     target_include_directories(LibJPEG INTERFACE ${INSTALL_DIR}/include)
     set_property(TARGET TURBOJPEG PROPERTY FOLDER "Dependencies")
 
diff --git a/cmake/dependency.openexr.cmake b/cmake/dependency.openexr.cmake
index eb32412..156f3d5 100644
--- a/cmake/dependency.openexr.cmake
+++ b/cmake/dependency.openexr.cmake
@@ -4,6 +4,11 @@
 # Output target: LibOpenEXR
 #
 
+if (USE_SYSTEM_LIBOPENEXR OR USE_SYSTEM_LIBS)
+    find_package(OpenEXR REQUIRED CONFIG)
+    add_library(LibOpenEXR ALIAS OpenEXR::OpenEXR)
+    return()
+endif()
 
 include(${EXTERNALPROJECT_INCLUDE_DIR}/external_project_common.cmake)
 include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.openjph.cmake)
diff --git a/cmake/dependency.png.cmake b/cmake/dependency.png.cmake
index 5b1e163..1c2d76c 100644
--- a/cmake/dependency.png.cmake
+++ b/cmake/dependency.png.cmake
@@ -3,6 +3,11 @@
 #
 # Output target: LibPNG
 
+if (USE_SYSTEM_LIBPNG OR USE_SYSTEM_LIBS)
+    find_package(PNG)
+    add_library(LibPNG ALIAS PNG::PNG)
+    return()
+endif()
 
 include(${EXTERNALPROJECT_INCLUDE_DIR}/external_project_common.cmake)
 
diff --git a/cmake/dependency.raw.cmake b/cmake/dependency.raw.cmake
index 9f13ff3..ec6c751 100644
--- a/cmake/dependency.raw.cmake
+++ b/cmake/dependency.raw.cmake
@@ -3,6 +3,12 @@
 #
 # Output target: LibRAW
 
+if (USE_SYSTEM_LIBRAW OR USE_SYSTEM_LIBS)
+    find_package(PkgConfig)
+    pkg_check_modules(LIBRAW REQUIRED IMPORTED_TARGET libraw)
+    add_library(LibRAW ALIAS PkgConfig::LIBRAW)
+    return()
+endif()
 
 include(${EXTERNALPROJECT_INCLUDE_DIR}/external_project_common.cmake)
 
diff --git a/cmake/dependency.tiff.cmake b/cmake/dependency.tiff.cmake
index e8ee2f9..7f3ccd5 100644
--- a/cmake/dependency.tiff.cmake
+++ b/cmake/dependency.tiff.cmake
@@ -3,6 +3,12 @@
 #
 # Output targets: LibTIFF
 
+if (USE_SYSTEM_LIBTIFF OR USE_SYSTEM_LIBS)
+    find_package(PkgConfig)
+    pkg_check_modules(LIBTIFF REQUIRED IMPORTED_TARGET libtiff-4)
+    add_library(libTIFF ALIAS PkgConfig::LIBTIFF)
+    return()
+endif()
 
 include(${EXTERNALPROJECT_INCLUDE_DIR}/external_project_common.cmake)
 include(${EXTERNALPROJECT_INCLUDE_DIR}/dependency.imath.cmake) # Only for half.h
diff --git a/cmake/dependency.webp.cmake b/cmake/dependency.webp.cmake
index 9988a66..c57d2c2 100644
--- a/cmake/dependency.webp.cmake
+++ b/cmake/dependency.webp.cmake
@@ -3,6 +3,12 @@
 #
 # Output target: LibWEBP
 
+if (USE_SYSTEM_LIBWEBP OR USE_SYSTEM_LIBS)
+    find_package(PkgConfig)
+    pkg_check_modules(LIBWEBP REQUIRED IMPORTED_TARGET libwebp)
+    add_library(LibWEBP ALIAS PkgConfig::LIBWEBP)
+    return()
+endif()
 
 include(${EXTERNALPROJECT_INCLUDE_DIR}/external_project_common.cmake)
 
diff --git a/cmake/dependency.yato.cmake b/cmake/dependency.yato.cmake
index c4eae69..0c1dbf6 100644
--- a/cmake/dependency.yato.cmake
+++ b/cmake/dependency.yato.cmake
@@ -4,6 +4,11 @@
 # Output target: LibYato
 # YATO_INCLUDE_DIR - includes
 
+if (USE_SYSTEM_YATO OR USE_SYSTEM_LIBS)
+    find_package(Yato REQUIRED CONFIG)
+    add_library(LibYato ALIAS Yato::Yato)
+    return()
+endif()
 
 include(${EXTERNALPROJECT_INCLUDE_DIR}/external_project_common.cmake)
 
diff --git a/cmake/dependency.zlib.cmake b/cmake/dependency.zlib.cmake
index 981643a..bad24f5 100644
--- a/cmake/dependency.zlib.cmake
+++ b/cmake/dependency.zlib.cmake
@@ -6,6 +6,11 @@
 if(NOT _ZLIB_DEP_INCLUDE_GUARD_)
 set(_ZLIB_DEP_INCLUDE_GUARD_ ON)
 
+if (USE_SYSTEM_ZLIB OR USE_SYSTEM_LIBS)
+    find_package(ZLIB REQUIRED)
+    add_library(LibZLIB ALIAS ZLIB::ZLIB)
+    return()
+endif()
 
 include(${EXTERNALPROJECT_INCLUDE_DIR}/external_project_common.cmake)