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/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef MODULES_VIDEO_CAPTURE_MAIN_SOURCE_WINDOWS_HELP_FUNCTIONS_DS_H_
#define MODULES_VIDEO_CAPTURE_MAIN_SOURCE_WINDOWS_HELP_FUNCTIONS_DS_H_
#include <dshow.h>
#include <type_traits>
#include <utility>
#include "api/scoped_refptr.h"
#include "rtc_base/ref_counter.h"
DEFINE_GUID(MEDIASUBTYPE_I420,
0x30323449,
0x0000,
0x0010,
0x80,
0x00,
0x00,
0xAA,
0x00,
0x38,
0x9B,
0x71);
DEFINE_GUID(MEDIASUBTYPE_HDYC,
0x43594448,
0x0000,
0x0010,
0x80,
0x00,
0x00,
0xAA,
0x00,
0x38,
0x9B,
0x71);
#define RELEASE_AND_CLEAR(p) \
if (p) { \
(p)->Release(); \
(p) = NULL; \
}
namespace webrtc {
namespace videocapturemodule {
LONGLONG GetMaxOfFrameArray(LONGLONG* maxFps, long size);
IPin* GetInputPin(IBaseFilter* filter);
IPin* GetOutputPin(IBaseFilter* filter, REFGUID Category);
BOOL PinMatchesCategory(IPin* pPin, REFGUID Category);
void ResetMediaType(AM_MEDIA_TYPE* media_type);
void FreeMediaType(AM_MEDIA_TYPE* media_type);
HRESULT CopyMediaType(AM_MEDIA_TYPE* target, const AM_MEDIA_TYPE* source);
// Helper function to make using scoped_refptr with COM interface pointers
// a little less awkward. rtc::scoped_refptr doesn't support the & operator
// or a way to receive values via an out ptr.
// The function is intentionally not called QueryInterface to make things less
// confusing for the compiler to figure out what the caller wants to do when
// called from within the context of a class that also implements COM
// interfaces.
template <class T>
HRESULT GetComInterface(IUnknown* object, rtc::scoped_refptr<T>* ptr) {
// This helper function is not meant to magically free ptr. If we do that
// we add code bloat to most places where it's not needed and make the code
// less readable since it's not clear at the call site that the pointer
// would get freed even inf QI() fails.
RTC_DCHECK(!ptr->get());
void* new_ptr = nullptr;
HRESULT hr = object->QueryInterface(__uuidof(T), &new_ptr);
if (SUCCEEDED(hr))
ptr->swap(reinterpret_cast<T**>(&new_ptr));
return hr;
}
// Provides a reference count implementation for COM (IUnknown derived) classes.
// The implementation uses atomics for managing the ref count.
template <class T>
class ComRefCount : public T {
public:
ComRefCount() {}
template <class P0>
explicit ComRefCount(P0&& p0) : T(std::forward<P0>(p0)) {}
STDMETHOD_(ULONG, AddRef)() override {
ref_count_.IncRef();
return 1;
}
STDMETHOD_(ULONG, Release)() override {
const auto status = ref_count_.DecRef();
if (status == RefCountReleaseStatus::kDroppedLastRef) {
delete this;
return 0;
}
return 1;
}
protected:
~ComRefCount() {}
private:
webrtc::webrtc_impl::RefCounter ref_count_{0};
};
} // namespace videocapturemodule
} // namespace webrtc
#endif // MODULES_VIDEO_CAPTURE_MAIN_SOURCE_WINDOWS_HELP_FUNCTIONS_DS_H_