wip: real coeffs extraction

CMakeLists.txt

@@ -195,6 +195,30 @@ if(DAEDALUS_BUILD_TOOLS)
             ${DAEDALUS_FFMPEG_PREFIX}/lib/libswresample.a
             m z pthread)
         set(FFMPEG_CFLAGS_OTHER "-DDAEDALUS_HAVE_H264_MB_INSPECT_CB=1")
+
+        # PR-A3+ optional: also point at the patched FFmpeg SOURCE TREE
+        # so the CLI can include libavcodec/h264dec.h directly and
+        # dereference H264Context fields (the side-buffer mb_inspect_coeffs
+        # added in marfrit-packages patch 0017, the cur_pic.f for
+        # pre-deblock pixel access, etc.).  When set, the internal-header
+        # include codepath is compiled in.
+        set(DAEDALUS_FFMPEG_SRC "" CACHE PATH
+            "Path to patched FFmpeg source tree (= path to FFmpeg/ checkout where build was run; contains config.h + libavcodec/h264dec.h). Empty = h264dec.h includes are disabled.")
+        if(DAEDALUS_FFMPEG_SRC)
+            message(STATUS "daedalus_decode_h264: FFmpeg source at ${DAEDALUS_FFMPEG_SRC}")
+            # IMPORTANT: source tree FIRST in -I order — its
+            # libavutil/common.h does #include "intmath.h" with HAVE_AV_CONFIG_H,
+            # which resolves to libavutil/intmath.h (in the source tree
+            # only — that header isn't installed since it's arch-dispatched).
+            # The installed-prefix include path's libavutil/common.h is the
+            # same file textually but resolves "intmath.h" against the
+            # install dir where it doesn't exist.
+            set(FFMPEG_INCLUDE_DIRS ${DAEDALUS_FFMPEG_SRC})
+            set(FFMPEG_CFLAGS_OTHER
+                "${FFMPEG_CFLAGS_OTHER} -DDAEDALUS_HAVE_H264_MB_INSPECT_COEFFS=1 -DHAVE_AV_CONFIG_H")
+            # Convert space-separated string to list (CMake idiom for compile flags).
+            separate_arguments(FFMPEG_CFLAGS_OTHER UNIX_COMMAND "${FFMPEG_CFLAGS_OTHER}")
+        endif()
     else()
         pkg_check_modules(FFMPEG REQUIRED libavcodec libavformat libavutil)
         message(STATUS "daedalus_decode_h264: system FFmpeg (no inspection callback)")