modules/video_capture/windows/help_functions_ds.cc

/*
 *  Copyright (c) 2012 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.
 */

#include <initguid.h>  // Must come before the help_functions_ds.h include so
                       // that DEFINE_GUID() entries will be defined in this
                       // object file.

#include "modules/video_capture/windows/help_functions_ds.h"

#include <cguid.h>

namespace webrtc {
namespace videocapturemodule {
// This returns minimum :), which will give max frame rate...
LONGLONG GetMaxOfFrameArray(LONGLONG* maxFps, long size) {
  LONGLONG maxFPS = maxFps[0];
  for (int i = 0; i < size; i++) {
    if (maxFPS > maxFps[i])
      maxFPS = maxFps[i];
  }
  return maxFPS;
}

IPin* GetInputPin(IBaseFilter* filter) {
  HRESULT hr;
  IPin* pin = NULL;
  IEnumPins* pPinEnum = NULL;
  filter->EnumPins(&pPinEnum);
  if (pPinEnum == NULL) {
    return NULL;
  }

  // get first unconnected pin
  hr = pPinEnum->Reset();  // set to first pin

  while (S_OK == pPinEnum->Next(1, &pin, NULL)) {
    PIN_DIRECTION pPinDir;
    pin->QueryDirection(&pPinDir);
    if (PINDIR_INPUT == pPinDir)  // This is an input pin
    {
      IPin* tempPin = NULL;
      if (S_OK != pin->ConnectedTo(&tempPin))  // The pint is not connected
      {
        pPinEnum->Release();
        return pin;
      }
    }
    pin->Release();
  }
  pPinEnum->Release();
  return NULL;
}

IPin* GetOutputPin(IBaseFilter* filter, REFGUID Category) {
  HRESULT hr;
  IPin* pin = NULL;
  IEnumPins* pPinEnum = NULL;
  filter->EnumPins(&pPinEnum);
  if (pPinEnum == NULL) {
    return NULL;
  }
  // get first unconnected pin
  hr = pPinEnum->Reset();  // set to first pin
  while (S_OK == pPinEnum->Next(1, &pin, NULL)) {
    PIN_DIRECTION pPinDir;
    pin->QueryDirection(&pPinDir);
    if (PINDIR_OUTPUT == pPinDir)  // This is an output pin
    {
      if (Category == GUID_NULL || PinMatchesCategory(pin, Category)) {
        pPinEnum->Release();
        return pin;
      }
    }
    pin->Release();
    pin = NULL;
  }
  pPinEnum->Release();
  return NULL;
}

BOOL PinMatchesCategory(IPin* pPin, REFGUID Category) {
  BOOL bFound = FALSE;
  IKsPropertySet* pKs = NULL;
  HRESULT hr = pPin->QueryInterface(IID_PPV_ARGS(&pKs));
  if (SUCCEEDED(hr)) {
    GUID PinCategory;
    DWORD cbReturned;
    hr = pKs->Get(AMPROPSETID_Pin, AMPROPERTY_PIN_CATEGORY, NULL, 0,
                  &PinCategory, sizeof(GUID), &cbReturned);
    if (SUCCEEDED(hr) && (cbReturned == sizeof(GUID))) {
      bFound = (PinCategory == Category);
    }
    pKs->Release();
  }
  return bFound;
}
}  // namespace videocapturemodule
}  // namespace webrtc