Sub-tile decoding: only allocate tile component buffer of the needed …

…dimension

Instead of being the full tile size.

* Use a sparse array mechanism to store code-blocks and intermediate stages of
  IDWT.
* IDWT, DC level shift and MCT stages are done just on that smaller array.
* Improve copy of tile component array to final image, by saving an intermediate
  buffer.
* For full-tile decoding at reduced resolution, only allocate the tile buffer to
  the reduced size, instead of the full-resolution size.

CMakeLists.txt

@@ -253,7 +253,7 @@ if(BUILD_JPIP_SERVER)
 endif()
 add_subdirectory(src/lib)
 option(BUILD_LUTS_GENERATOR "Build utility to generate t1_luts.h" OFF)
-option(BUILD_BENCH_DWT "Build bench_dwt utility (development benchmark)" OFF)
+option(BUILD_UNIT_TESTS "Build unit tests (bench_dwt, test_sparse_array, etc..)" OFF)
 
 #-----------------------------------------------------------------------------
 # Build Applications

src/lib/openjp2/CMakeLists.txt

@@ -54,6 +54,8 @@ set(OPENJPEG_SRCS
   ${CMAKE_CURRENT_SOURCE_DIR}/opj_malloc.c
   ${CMAKE_CURRENT_SOURCE_DIR}/opj_malloc.h
   ${CMAKE_CURRENT_SOURCE_DIR}/opj_stdint.h
+  ${CMAKE_CURRENT_SOURCE_DIR}/sparse_array.c
+  ${CMAKE_CURRENT_SOURCE_DIR}/sparse_array.h
 )
 if(BUILD_JPIP)
   add_definitions(-DUSE_JPIP)
@@ -192,12 +194,20 @@ if(OPJ_USE_THREAD AND Threads_FOUND AND CMAKE_USE_PTHREADS_INIT)
    TARGET_LINK_LIBRARIES(${OPENJPEG_LIBRARY_NAME} ${CMAKE_THREAD_LIBS_INIT})
 endif(OPJ_USE_THREAD AND Threads_FOUND AND CMAKE_USE_PTHREADS_INIT)
 
-if(BUILD_BENCH_DWT)
-    add_executable(bench_dwt bench_dwt.c dwt.c opj_malloc.c thread.c)
+if(BUILD_UNIT_TESTS)
+    add_executable(bench_dwt bench_dwt.c)
     if(UNIX)
-        target_link_libraries(bench_dwt m)
+        target_link_libraries(bench_dwt m ${OPENJPEG_LIBRARY_NAME})
     endif()
     if(OPJ_USE_THREAD AND Threads_FOUND AND CMAKE_USE_PTHREADS_INIT)
         target_link_libraries(bench_dwt ${CMAKE_THREAD_LIBS_INIT})
     endif(OPJ_USE_THREAD AND Threads_FOUND AND CMAKE_USE_PTHREADS_INIT)
-endif(BUILD_BENCH_DWT)
+
+    add_executable(test_sparse_array test_sparse_array.c)
+    if(UNIX)
+        target_link_libraries(test_sparse_array m ${OPENJPEG_LIBRARY_NAME})
+    endif()
+    if(OPJ_USE_THREAD AND Threads_FOUND AND CMAKE_USE_PTHREADS_INIT)
+        target_link_libraries(test_sparse_array ${CMAKE_THREAD_LIBS_INIT})
+    endif(OPJ_USE_THREAD AND Threads_FOUND AND CMAKE_USE_PTHREADS_INIT)
+endif(BUILD_UNIT_TESTS)

src/lib/openjp2/bench_dwt.c

@@ -198,10 +198,11 @@ int main(int argc, char** argv)
 
     memset(&tcd, 0, sizeof(tcd));
     tcd.thread_pool = tp;
-    tcd.decoded_x0 = (OPJ_UINT32)tilec.x0;
-    tcd.decoded_y0 = (OPJ_UINT32)tilec.y0;
-    tcd.decoded_x1 = (OPJ_UINT32)tilec.x1;
-    tcd.decoded_y1 = (OPJ_UINT32)tilec.y1;
+    tcd.whole_tile_decoding = OPJ_TRUE;
+    tcd.win_x0 = (OPJ_UINT32)tilec.x0;
+    tcd.win_y0 = (OPJ_UINT32)tilec.y0;
+    tcd.win_x1 = (OPJ_UINT32)tilec.x1;
+    tcd.win_y1 = (OPJ_UINT32)tilec.y1;
     tcd.tcd_image = &tcd_image;
     memset(&tcd_image, 0, sizeof(tcd_image));
     tcd_image.tiles = &tcd_tile;