build(streamer): make ZED SDK optional

CMakeLists.txt

@@ -56,12 +56,11 @@ find_package(ZeroMQ QUIET)
 find_package(spdlog REQUIRED)
 find_package(Protobuf REQUIRED)
 find_package(PkgConfig REQUIRED)
-if (CVMMAP_BUILD_ZED_SVO_GRID_TO_MP4)
-	find_package(OpenCV REQUIRED COMPONENTS core imgproc)
-endif()
 find_package(rvl CONFIG QUIET)
 set(ZED_DIR "/usr/local/zed" CACHE PATH "Path to the local ZED SDK")
-find_package(ZED REQUIRED)
+find_package(ZED QUIET)
+set(CVMMAP_HAS_ZED_SDK OFF)
+if (ZED_FOUND)
 	find_package(CUDA ${ZED_CUDA_VERSION} REQUIRED)
 	find_library(CVMMAP_STREAMER_LIBUSB_LIBRARY NAMES usb-1.0 libusb-1.0)
 	if (CVMMAP_STREAMER_LIBUSB_LIBRARY)
@@ -75,6 +74,17 @@ if (CVMMAP_STREAMER_LIBUSB_LIBRARY)
 		endforeach()
 		set(ZED_LIBRARIES "${_CVMMAP_STREAMER_ZED_LIBRARIES}")
 	endif()
+	set(CVMMAP_HAS_ZED_SDK ON)
+	message(STATUS "ZED SDK found: enabling zed_svo_to_mcap and zed_svo_to_mp4")
+else()
+	message(STATUS "ZED SDK not found: skipping ZED conversion tools")
+endif()
+
+if (CVMMAP_BUILD_ZED_SVO_GRID_TO_MP4 AND CVMMAP_HAS_ZED_SDK)
+	find_package(OpenCV REQUIRED COMPONENTS core imgproc)
+elseif (CVMMAP_BUILD_ZED_SVO_GRID_TO_MP4)
+	message(STATUS "CVMMAP_BUILD_ZED_SVO_GRID_TO_MP4=ON but ZED SDK is unavailable; zed_svo_grid_to_mp4 will not be built")
+endif()
 
 add_subdirectory(third_party)
 
@@ -343,6 +353,9 @@ set_target_properties(mcap_replay_tester PROPERTIES
 	OUTPUT_NAME "mcap_replay_tester"
 	RUNTIME_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/bin")
 
+set(CVMMAP_STREAMER_INSTALL_TARGETS cvmmap_streamer)
+
+if (CVMMAP_HAS_ZED_SDK)
 	add_executable(
 		zed_svo_to_mcap
 		src/tools/zed_svo_to_mcap.cpp
@@ -373,6 +386,7 @@ endif()
 	set_target_properties(zed_svo_to_mcap PROPERTIES
 		OUTPUT_NAME "zed_svo_to_mcap"
 		RUNTIME_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/bin")
+	list(APPEND CVMMAP_STREAMER_INSTALL_TARGETS zed_svo_to_mcap)
 
 	add_library(
 		cvmmap_streamer_zed_svo_mp4_support
@@ -419,6 +433,7 @@ endif()
 	set_target_properties(zed_svo_to_mp4 PROPERTIES
 		OUTPUT_NAME "zed_svo_to_mp4"
 		RUNTIME_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/bin")
+	list(APPEND CVMMAP_STREAMER_INSTALL_TARGETS zed_svo_to_mp4)
 
 	if (CVMMAP_BUILD_ZED_SVO_GRID_TO_MP4)
 		add_executable(
@@ -451,18 +466,10 @@ if (CVMMAP_BUILD_ZED_SVO_GRID_TO_MP4)
 		set_target_properties(zed_svo_grid_to_mp4 PROPERTIES
 			OUTPUT_NAME "zed_svo_grid_to_mp4"
 			RUNTIME_OUTPUT_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/bin")
+		list(APPEND CVMMAP_STREAMER_INSTALL_TARGETS zed_svo_grid_to_mp4)
+	endif()
 endif()
 
 install(
-	TARGETS
-		cvmmap_streamer
-		zed_svo_to_mcap
-		zed_svo_to_mp4
+	TARGETS ${CVMMAP_STREAMER_INSTALL_TARGETS}
 	RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")
-
-if (CVMMAP_BUILD_ZED_SVO_GRID_TO_MP4)
-	install(
-		TARGETS
-			zed_svo_grid_to_mp4
-		RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}")
-endif()

README.md

@@ -45,6 +45,17 @@ cmake -B build -S .
 cmake --build build
 ```
 
+When the ZED SDK is available, the build also enables `zed_svo_to_mcap` and
+`zed_svo_to_mp4` automatically. When the SDK is absent, those tools are skipped
+and the main streamer plus non-ZED testers still build normally.
+
+`zed_svo_grid_to_mp4` remains optional and additionally requires OpenCV. Disable
+it explicitly with:
+
+```bash
+cmake -B build -S . -DCVMMAP_BUILD_ZED_SVO_GRID_TO_MP4=OFF
+```
+
 ```bash
 # Use a local cv-mmap build tree
 cmake -B build -S . \
@@ -60,6 +71,8 @@ ls -la build/{cvmmap_streamer,rtp_receiver_tester,rtmp_stub_tester}
 
 ### ZED SVO/SVO2 To MP4
 
+This tool is only built when the ZED SDK is detected during CMake configure.
+
 The repo also includes an offline conversion tool for the left ZED color stream:
 
 ```bash
@@ -130,6 +143,9 @@ The batch tool mirrors the common encoder options from `zed_svo_to_mp4`, skips e
 
 ### ZED SVO Grid To MP4
 
+This tool is only built when the ZED SDK is detected and
+`CVMMAP_BUILD_ZED_SVO_GRID_TO_MP4=ON`.
+
 Use the grid converter to merge four synced ZED recordings into a 2x2 CCTV-style MP4 with a Unix timestamp overlay in the top-left corner:
 
 ```bash
@@ -213,6 +229,9 @@ timestamp,activity,group_path,segment_dir,camera,relative_path
 
 ### Batch ZED Segments To MCAP
 
+This workflow depends on the `zed_svo_to_mcap` binary, which is only built when
+the ZED SDK is detected during CMake configure.
+
 Use the wrapper to recurse through a dataset root, run `zed_svo_to_mcap --segment-dir` on every matched multi-camera segment, and show one aggregate tqdm progress bar:
 
 ```bash