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| author | fcolin | 2011-11-18 12:14:12 +0000 |
|---|---|---|
| committer | fcolin | 2011-11-18 12:14:12 +0000 |
| commit | 6bcf419d2e8f739b432d4790d1ba9d48ab65365b (patch) | |
| tree | 92815e16f189c8e328dff4fcfa38ebe1d0217fdd /ARMFCaptureD3D/BufferLock.h | |
| parent | 487e963b081d7ffe2ddf489e11d927982c9101a6 (diff) | |
| download | amilis-6bcf419d2e8f739b432d4790d1ba9d48ab65365b.zip amilis-6bcf419d2e8f739b432d4790d1ba9d48ab65365b.tar.gz amilis-6bcf419d2e8f739b432d4790d1ba9d48ab65365b.tar.bz2 amilis-6bcf419d2e8f739b432d4790d1ba9d48ab65365b.tar.xz | |
Diffstat (limited to 'ARMFCaptureD3D/BufferLock.h')
| -rw-r--r-- | ARMFCaptureD3D/BufferLock.h | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/ARMFCaptureD3D/BufferLock.h b/ARMFCaptureD3D/BufferLock.h new file mode 100644 index 0000000..d566d5b --- /dev/null +++ b/ARMFCaptureD3D/BufferLock.h @@ -0,0 +1,125 @@ +//////////////////////////////////////////////////////////////////////////
+//
+// THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF
+// ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
+// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
+// PARTICULAR PURPOSE.
+//
+// Copyright (c) Microsoft Corporation. All rights reserved.
+//
+//////////////////////////////////////////////////////////////////////////
+
+
+
+#pragma once
+
+
+//-------------------------------------------------------------------
+// VideoBufferLock class
+//
+// Locks a video buffer that might or might not support IMF2DBuffer.
+//
+//-------------------------------------------------------------------
+
+class VideoBufferLock
+{
+public:
+ VideoBufferLock(IMFMediaBuffer *pBuffer) : m_p2DBuffer(NULL), m_bLocked(FALSE)
+ {
+ m_pBuffer = pBuffer;
+ m_pBuffer->AddRef();
+
+ // Query for the 2-D buffer interface. OK if this fails.
+ (void)m_pBuffer->QueryInterface(IID_PPV_ARGS(&m_p2DBuffer));
+ }
+
+ ~VideoBufferLock()
+ {
+ UnlockBuffer();
+ SafeRelease(&m_pBuffer);
+ SafeRelease(&m_p2DBuffer);
+ }
+
+ //-------------------------------------------------------------------
+ // LockBuffer
+ //
+ // Locks the buffer. Returns a pointer to scan line 0 and returns the stride.
+ //
+ // The caller must provide the default stride as an input parameter, in case
+ // the buffer does not expose IMF2DBuffer. You can calculate the default stride
+ // from the media type.
+ //-------------------------------------------------------------------
+
+ HRESULT LockBuffer(
+ LONG lDefaultStride, // Minimum stride (with no padding).
+ DWORD dwHeightInPixels, // Height of the image, in pixels.
+ BYTE **ppbScanLine0, // Receives a pointer to the start of scan line 0.
+ LONG *plStride // Receives the actual stride.
+ )
+ {
+ HRESULT hr = S_OK;
+ DWORD cbMaxLength;
+ DWORD cbCurrentLength;
+
+ // Use the 2-D version if available.
+ if (m_p2DBuffer)
+ {
+ hr = m_p2DBuffer->Lock2D(ppbScanLine0, plStride);
+ }
+ else
+ {
+ // Use non-2D version.
+ BYTE *pData = NULL;
+
+ hr = m_pBuffer->Lock(&pData, &cbMaxLength, &cbCurrentLength);
+ if (SUCCEEDED(hr))
+ {
+ *plStride = lDefaultStride;
+ if (lDefaultStride < 0)
+ {
+ // Bottom-up orientation. Return a pointer to the start of the
+ // last row *in memory* which is the top row of the image.
+ *ppbScanLine0 = pData + abs(lDefaultStride) * (dwHeightInPixels - 1);
+ }
+ else
+ {
+ // Top-down orientation. Return a pointer to the start of the
+ // buffer.
+ *ppbScanLine0 = pData;
+ }
+ }
+ }
+
+ m_bLocked = (SUCCEEDED(hr));
+
+ return hr;
+ }
+
+ //-------------------------------------------------------------------
+ // UnlockBuffer
+ //
+ // Unlocks the buffer. Called automatically by the destructor.
+ //-------------------------------------------------------------------
+
+ void UnlockBuffer()
+ {
+ if (m_bLocked)
+ {
+ if (m_p2DBuffer)
+ {
+ (void)m_p2DBuffer->Unlock2D();
+ }
+ else
+ {
+ (void)m_pBuffer->Unlock();
+ }
+ m_bLocked = FALSE;
+ }
+ }
+
+private:
+ IMFMediaBuffer *m_pBuffer;
+ IMF2DBuffer *m_p2DBuffer;
+
+ BOOL m_bLocked;
+};
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