Rework Video Capture backend to allow better isolation.

projects/VisualStudio2013/mupen64plus-core.vcxproj

@@ -41,11 +41,13 @@
     <ClCompile Include="..\..\src\api\debugger.c" />
     <ClCompile Include="..\..\src\api\frontend.c" />
     <ClCompile Include="..\..\src\api\vidext.c" />
+    <ClCompile Include="..\..\src\backends\api\video_capture_backend.c" />
     <ClCompile Include="..\..\src\backends\plugins_compat\input_plugin_compat.c" />
     <ClCompile Include="..\..\src\backends\plugins_compat\audio_plugin_compat.c" />
     <ClCompile Include="..\..\src\backends\clock_ctime_plus_delta.c" />
+    <ClCompile Include="..\..\src\backends\dummy_video_capture.c" />
     <ClCompile Include="..\..\src\backends\file_storage.c" />
-    <ClCompile Include="..\..\src\backends\opencv_video_backend.cpp">
+    <ClCompile Include="..\..\src\backends\opencv_video_capture.cpp">
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='New_Dynarec_Debug|Win32'">true</ExcludedFromBuild>
@@ -55,7 +57,6 @@
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='New_Dynarec_Release|Win32'">true</ExcludedFromBuild>
       <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='New_Dynarec_Release|x64'">true</ExcludedFromBuild>
     </ClCompile>
-    <ClCompile Include="..\..\src\backends\dummy_video_backend.c" />
     <ClCompile Include="..\..\src\debugger\dbg_breakpoints.c" />
     <ClCompile Include="..\..\src\debugger\dbg_debugger.c" />
     <ClCompile Include="..\..\src\debugger\dbg_decoder.c" />
@@ -266,20 +267,9 @@
     <ClInclude Include="..\..\src\backends\api\joybus.h" />
     <ClInclude Include="..\..\src\backends\api\rumble_backend.h" />
     <ClInclude Include="..\..\src\backends\api\storage_backend.h" />
-    <ClInclude Include="..\..\src\backends\api\video_backend.h" />
+    <ClInclude Include="..\..\src\backends\api\video_capture_backend.h" />
     <ClInclude Include="..\..\src\backends\clock_ctime_plus_delta.h" />
     <ClInclude Include="..\..\src\backends\file_storage.h" />
-    <ClInclude Include="..\..\src\backends\opencv_video_backend.h">
-      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
-      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">true</ExcludedFromBuild>
-      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='New_Dynarec_Debug|Win32'">true</ExcludedFromBuild>
-      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='New_Dynarec_Debug|x64'">true</ExcludedFromBuild>
-      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
-      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|x64'">true</ExcludedFromBuild>
-      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='New_Dynarec_Release|Win32'">true</ExcludedFromBuild>
-      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='New_Dynarec_Release|x64'">true</ExcludedFromBuild>
-    </ClInclude>
-    <ClInclude Include="..\..\src\backends\dummy_video_backend.h" />
     <ClInclude Include="..\..\src\backends\plugins_compat\plugins_compat.h" />
     <ClInclude Include="..\..\src\api\vidext_sdl2_compat.h" />
     <ClInclude Include="..\..\src\debugger\dbg_breakpoints.h" />

projects/VisualStudio2013/mupen64plus-core.vcxproj.filters

@@ -192,10 +192,10 @@
     <ClCompile Include="..\..\src\backends\clock_ctime_plus_delta.c">
       <Filter>backends</Filter>
     </ClCompile>
-    <ClCompile Include="..\..\src\backends\dummy_video_backend.c">
+    <ClCompile Include="..\..\src\backends\dummy_video_capture.c">
       <Filter>backends</Filter>
     </ClCompile>
-    <ClCompile Include="..\..\src\backends\opencv_video_backend.cpp">
+    <ClCompile Include="..\..\src\backends\opencv_video_capture.cpp">
       <Filter>backends</Filter>
     </ClCompile>
     <ClCompile Include="..\..\src\device\dd\dd_controller.c">
@@ -300,6 +300,9 @@
     <ClCompile Include="..\..\src\device\pif\bootrom_hle.c">
       <Filter>device\pif</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\backends\api\video_capture_backend.c">
+      <Filter>backends</Filter>
+    </ClCompile>
     <ClCompile Include="..\..\src\backends\plugins_compat\audio_plugin_compat.c">
       <Filter>backends\plugins_compat</Filter>
     </ClCompile>
@@ -494,12 +497,6 @@
     <ClInclude Include="..\..\src\backends\clock_ctime_plus_delta.h">
       <Filter>backends</Filter>
     </ClInclude>
-    <ClInclude Include="..\..\src\backends\dummy_video_backend.h">
-      <Filter>backends</Filter>
-    </ClInclude>
-    <ClInclude Include="..\..\src\backends\opencv_video_backend.h">
-      <Filter>backends</Filter>
-    </ClInclude>
     <ClInclude Include="..\..\src\device\dd\dd_controller.h">
       <Filter>device\dd</Filter>
     </ClInclude>
@@ -635,7 +632,7 @@
     <ClInclude Include="..\..\src\backends\api\storage_backend.h">
       <Filter>backends\api</Filter>
     </ClInclude>
-    <ClInclude Include="..\..\src\backends\api\video_backend.h">
+    <ClInclude Include="..\..\src\backends\api\video_capture_backend.h">
       <Filter>backends\api</Filter>
     </ClInclude>
     <ClInclude Include="..\..\src\backends\plugins_compat\plugins_compat.h">

projects/unix/Makefile

@@ -455,11 +455,12 @@ SOURCE = \
     $(SRCDIR)/api/debugger.c \
     $(SRCDIR)/api/frontend.c \
     $(SRCDIR)/api/vidext.c \
+    $(SRCDIR)/backends/api/video_capture_backend.c \
     $(SRCDIR)/backends/plugins_compat/audio_plugin_compat.c \
     $(SRCDIR)/backends/plugins_compat/input_plugin_compat.c \
     $(SRCDIR)/backends/clock_ctime_plus_delta.c \
+    $(SRCDIR)/backends/dummy_video_capture.c \
     $(SRCDIR)/backends/file_storage.c \
-    $(SRCDIR)/backends/dummy_video_backend.c \
     $(SRCDIR)/device/cart/cart.c \
     $(SRCDIR)/device/cart/af_rtc.c \
     $(SRCDIR)/device/cart/cart_rom.c \
@@ -629,7 +630,7 @@ ifeq ($(DEBUGGER), 1)
 endif
 
 ifeq ($(OPENCV), 1)
-  SOURCE += $(SRCDIR)/backends/opencv_video_backend.cpp
+  SOURCE += $(SRCDIR)/backends/opencv_video_capture.cpp
   CFLAGS += -DM64P_OPENCV
 endif
 

src/backends/dummy_video_backend.c → src/backends/api/video_capture_backend.c

@@ -1,5 +1,5 @@
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
- *   Mupen64plus - dummy_video_backend.c                                   *
+ *   Mupen64plus - video_capture_backend.c                                 *
  *   Mupen64Plus homepage: https://mupen64plus.org/                        *
  *   Copyright (C) 2018 Bobby Smiles                                       *
  *                                                                         *
@@ -19,28 +19,38 @@
  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.          *
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-#include "backends/dummy_video_backend.h"
-#include "backends/api/video_backend.h"
+#include "video_capture_backend.h"
 
-#include "api/m64p_types.h"
+#include <string.h>
 
-static m64p_error dummy_video_open(void* vin, unsigned int width, unsigned int height)
-{
-    return M64ERR_SUCCESS;
-}
+/* exported video capture backends */
+extern const struct video_capture_backend_interface g_idummy_video_capture_backend;
+#if defined(M64P_OPENCV)
+extern const struct video_capture_backend_interface g_iopencv_video_capture_backend;
+#endif
 
-static void dummy_video_close(void* vin)
-{
-}
 
-static m64p_error dummy_grab_image(void* vin, void* data)
+const struct video_capture_backend_interface* g_video_capture_backend_interfaces[] =
 {
-    return M64ERR_UNSUPPORTED;
-}
+#if defined(M64P_OPENCV)
+    &g_iopencv_video_capture_backend,
+#endif
+    &g_idummy_video_capture_backend,
+    NULL /* sentinel - must be last element */
+};
 
-const struct video_input_backend_interface g_idummy_video_input_backend =
+
+const struct video_capture_backend_interface* get_video_capture_backend(const char* name)
 {
-    dummy_video_open,
-    dummy_video_close,
-    dummy_grab_image
-};
+    const struct video_capture_backend_interface** i;
+
+    /* passing NULL or empty string gives the dummy video input backend interface */
+    if (!name || strlen(name) == 0) { return &g_idummy_video_capture_backend; }
+
+    /* iterate through interfaces to find matching name */
+    for (i = g_video_capture_backend_interfaces; (*i) != NULL; ++i) {
+        if (strcmp((*i)->name, name) == 0) { return (*i); }
+    }
+
+    return NULL;
+}

src/backends/api/video_backend.h → src/backends/api/video_capture_backend.h

@@ -1,5 +1,5 @@
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
- *   Mupen64plus - video_backend.h                                         *
+ *   Mupen64plus - video_capture_backend.h                                 *
  *   Mupen64Plus homepage: https://mupen64plus.org/                        *
  *   Copyright (C) 2017 Bobby Smiles                                       *
  *                                                                         *
@@ -19,13 +19,43 @@
  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.          *
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-#ifndef M64P_BACKENDS_API_VIDEO_BACKEND_H
-#define M64P_BACKENDS_API_VIDEO_BACKEND_H
+#ifndef M64P_BACKENDS_API_VIDEO_CAPTURE_BACKEND_H
+#define M64P_BACKENDS_API_VIDEO_CAPTURE_BACKEND_H
 
 #include "api/m64p_types.h"
 
-struct video_input_backend_interface
+/* Define default video capture backend
+ * if not defined by Makefile/msvc
+ */
+#if !defined(DEFAULT_VIDEO_CAPTURE_BACKEND)
+#if defined(M64P_OPENCV)
+#define DEFAULT_VIDEO_CAPTURE_BACKEND "opencv"
+#else
+#define DEFAULT_VIDEO_CAPTURE_BACKEND ""
+#endif
+#endif
+
+
+struct video_capture_backend_interface
 {
+    /* Backend class name.
+     * Must be unique.
+     */
+    const char* name;
+
+    /* Initialize backend instance (*vin)
+     * using (when provided) parameters from config section.
+     *
+     * Returns M64ERR_SUCCESS on success.
+     *
+     * You must call corresponding release method to release any allocated resources.
+     */
+    m64p_error (*init)(void** vin, const char* section);
+
+    /* Release backend instance and any associated resouces.
+     */
+    void (*release)(void* vin);
+
     /* Open a video stream with following properties (width, height)
      * Returns M64ERR_SUCCESS on success.
      */
@@ -41,4 +71,10 @@ struct video_input_backend_interface
     m64p_error (*grab_image)(void* vin, void* data);
 };
 
+/* collection of available video capture backends */
+extern const struct video_capture_backend_interface* g_video_capture_backend_interfaces[];
+
+/* helper function which find backend by name (or dummy when NULL/empty) */
+const struct video_capture_backend_interface* get_video_capture_backend(const char* name);
+
 #endif

src/backends/opencv_video_backend.h → src/backends/dummy_video_capture.c

@@ -1,5 +1,5 @@
 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
- *   Mupen64plus - opencv_video_backend.h                                  *
+ *   Mupen64plus - dummy_video_capture.c                                   *
  *   Mupen64Plus homepage: https://mupen64plus.org/                        *
  *   Copyright (C) 2017 Bobby Smiles                                       *
  *                                                                         *
@@ -19,33 +19,66 @@
  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.          *
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-#ifndef M64P_BACKENDS_OPENCV_VIDEO_BACKEND_H
-#define M64P_BACKENDS_OPENCV_VIDEO_BACKEND_H
+#include "backends/api/video_capture_backend.h"
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+#include <stdlib.h>
+#include <string.h>
 
-#include "backends/api/video_backend.h"
+/* Dummy video capture backend
+ *
+ * Returns a black frame
+ */
+struct dummy_video_capture
+{
+    /* BGR frame size (no stride) */
+    size_t size;
+};
 
-struct opencv_video_backend
+static m64p_error dummy_init(void** vcap, const char* config)
 {
-    char* device;
-    unsigned int width;
-    unsigned int height;
+    struct dummy_video_capture* dummy = malloc(sizeof(*dummy));
+    if (dummy == NULL) {
+        *vcap = NULL;
+        return M64ERR_NO_MEMORY;
+    }
 
-    /* using void* to avoid leaking C++ stuff in this header */
-    void* cap;
-};
+    memset(dummy, 0, sizeof(*dummy));
 
-#if 0
-void cv_imshow(const char* name, unsigned int width, unsigned int height, int channels, void* data);
-#endif
+    *vcap = dummy;
+    return M64ERR_SUCCESS;
+}
 
-extern const struct video_input_backend_interface g_iopencv_video_input_backend;
+static void dummy_release(void* vcap)
+{
+    free(vcap);
+}
 
-#ifdef __cplusplus
+static m64p_error dummy_open(void* vcap, unsigned int width, unsigned int height)
+{
+    struct dummy_video_capture* dummy = (struct dummy_video_capture*)vcap;
+    dummy->size = 3 * width * height;
+    return M64ERR_SUCCESS;
 }
-#endif
 
-#endif
+static void dummy_close(void* vcap)
+{
+    struct dummy_video_capture* dummy = (struct dummy_video_capture*)vcap;
+    dummy->size = 0;
+}
+
+static m64p_error dummy_grab_image(void* vcap, void* data)
+{
+    struct dummy_video_capture* dummy = (struct dummy_video_capture*)vcap;
+    memset(data, 0, dummy->size);
+    return M64ERR_SUCCESS;
+}
+
+const struct video_capture_backend_interface g_idummy_video_capture_backend =
+{
+    "dummy",
+    dummy_init,
+    dummy_release,
+    dummy_open,
+    dummy_close,
+    dummy_grab_image
+};