Camera (Windows): init support

2026-09-13 02:42:09 +02:00 · 2024-02-02 16:42:47 +08:00
parent 246ad6d288
commit cba22b7155
4 changed files with 122 additions and 17 deletions
@@ -0,0 +1,95 @@
+extern "C" {
+#include "camera.h"
+#include "common/library.h"
+}
+#include "util/windows/com.hpp"
+#include "util/windows/unicode.hpp"
+
+#include <initguid.h>
+#include <mfapi.h>
+#include <mfidl.h>
+
+template <typename Fn>
+struct on_scope_exit {
+    on_scope_exit(Fn &&fn): _fn(std::move(fn)) {}
+    ~on_scope_exit() { this->_fn(); }
+
+private:
+    Fn _fn;
+};
+
+extern "C"
+const char* ffDetectCamera(FF_MAYBE_UNUSED FFlist* result)
+{
+    // TODO: check if supported by Windows Server Core
+
+    const char* error = ffInitCom();
+    if (error)
+        return error;
+
+    IMFAttributes* FF_AUTO_RELEASE_COM_OBJECT attrs = nullptr;
+    if (FAILED(MFCreateAttributes(&attrs, 1)))
+        return "MFCreateAttributes() failed";
+
+    if (FAILED(attrs->SetGUID(
+        MF_DEVSOURCE_ATTRIBUTE_SOURCE_TYPE,
+        MF_DEVSOURCE_ATTRIBUTE_SOURCE_TYPE_VIDCAP_GUID
+    )))
+        return "SetGUID(MF_*) failed";
+
+    IMFActivate** devices = NULL;
+    uint32_t count;
+
+    if (FAILED(MFEnumDeviceSources(attrs, &devices, &count)))
+        return "MFEnumDeviceSources() failed";
+
+    for (uint32_t i = 0; i < count; i++)
+    {
+        IMFActivate* device = devices[i];
+
+        wchar_t buffer[256];
+        uint32_t length = 0;
+        if (FAILED(device->GetString(MF_DEVSOURCE_ATTRIBUTE_FRIENDLY_NAME, buffer, sizeof(buffer), &length)) || length == 0)
+            continue;
+
+        FFCameraResult* camera = (FFCameraResult*) ffListAdd(result);
+        ffStrbufInitNWS(&camera->name, length, buffer);
+        ffStrbufInit(&camera->vendor);
+        ffStrbufInit(&camera->id);
+        camera->width = 0;
+        camera->height = 0;
+
+        if (SUCCEEDED(device->GetString(MF_DEVSOURCE_ATTRIBUTE_SOURCE_TYPE_VIDCAP_SYMBOLIC_LINK, buffer, sizeof(buffer), &length)) && length > 0)
+            ffStrbufSetNWS(&camera->id, length, buffer);
+
+        IMFMediaSource* FF_AUTO_RELEASE_COM_OBJECT source = nullptr;
+        if (FAILED(device->ActivateObject(IID_PPV_ARGS(&source))))
+            continue;
+
+        on_scope_exit destroySource([&] { source->Shutdown(); });
+
+        IMFPresentationDescriptor* FF_AUTO_RELEASE_COM_OBJECT pd = nullptr;
+        if (FAILED(source->CreatePresentationDescriptor(&pd)))
+            continue;
+
+        IMFStreamDescriptor* FF_AUTO_RELEASE_COM_OBJECT sd = NULL;
+        BOOL selected;
+        if (FAILED(pd->GetStreamDescriptorByIndex(0, &selected, &sd)))
+            continue;
+
+        IMFMediaTypeHandler* FF_AUTO_RELEASE_COM_OBJECT handler = NULL;
+        if (FAILED(sd->GetMediaTypeHandler(&handler)))
+            continue;
+
+        // Assume first type is the maximum resolution
+        IMFMediaType* FF_AUTO_RELEASE_COM_OBJECT type = NULL;
+        if (FAILED(handler->GetMediaTypeByIndex(0, &type)))
+            continue;
+
+        MFGetAttributeSize(type, MF_MT_FRAME_SIZE, &camera->width, &camera->height);
+    }
+
+    CoTaskMemFree(devices);
+
+    return nullptr;
+}