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TMessagesProj/jni/voip/webrtc/modules/desktop_capture/desktop_frame.h

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+/*
+ *  Copyright (c) 2013 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_DESKTOP_CAPTURE_DESKTOP_FRAME_H_
+#define MODULES_DESKTOP_CAPTURE_DESKTOP_FRAME_H_
+
+#include <stdint.h>
+
+#include <memory>
+#include <vector>
+
+#include "modules/desktop_capture/desktop_geometry.h"
+#include "modules/desktop_capture/desktop_region.h"
+#include "modules/desktop_capture/shared_memory.h"
+#include "rtc_base/system/rtc_export.h"
+
+namespace webrtc {
+
+const float kStandardDPI = 96.0f;
+
+// DesktopFrame represents a video frame captured from the screen.
+class RTC_EXPORT DesktopFrame {
+ public:
+  // DesktopFrame objects always hold BGRA data.
+  static const int kBytesPerPixel = 4;
+
+  virtual ~DesktopFrame();
+
+  DesktopFrame(const DesktopFrame&) = delete;
+  DesktopFrame& operator=(const DesktopFrame&) = delete;
+
+  // Returns the rectangle in full desktop coordinates to indicate it covers
+  // the area of top_left() to top_letf() + size() / scale_factor().
+  DesktopRect rect() const;
+
+  // Returns the scale factor from DIPs to physical pixels of the frame.
+  // Assumes same scale in both X and Y directions at present.
+  float scale_factor() const;
+
+  // Size of the frame. In physical coordinates, mapping directly from the
+  // underlying buffer.
+  const DesktopSize& size() const { return size_; }
+
+  // The top-left of the frame in full desktop coordinates. E.g. the top left
+  // monitor should start from (0, 0). The desktop coordinates may be scaled by
+  // OS, but this is always consistent with the MouseCursorMonitor.
+  const DesktopVector& top_left() const { return top_left_; }
+  void set_top_left(const DesktopVector& top_left) { top_left_ = top_left; }
+
+  // Distance in the buffer between two neighboring rows in bytes.
+  int stride() const { return stride_; }
+
+  // Data buffer used for the frame.
+  uint8_t* data() const { return data_; }
+
+  // SharedMemory used for the buffer or NULL if memory is allocated on the
+  // heap. The result is guaranteed to be deleted only after the frame is
+  // deleted (classes that inherit from DesktopFrame must ensure it).
+  SharedMemory* shared_memory() const { return shared_memory_; }
+
+  // Indicates region of the screen that has changed since the previous frame.
+  const DesktopRegion& updated_region() const { return updated_region_; }
+  DesktopRegion* mutable_updated_region() { return &updated_region_; }
+
+  // DPI of the screen being captured. May be set to zero, e.g. if DPI is
+  // unknown.
+  const DesktopVector& dpi() const { return dpi_; }
+  void set_dpi(const DesktopVector& dpi) { dpi_ = dpi; }
+
+  // Indicates if this frame may have the mouse cursor in it. Capturers that
+  // support cursor capture may set this to true. If the cursor was
+  // outside of the captured area, this may be true even though the cursor is
+  // not in the image.
+  bool may_contain_cursor() const { return may_contain_cursor_; }
+  void set_may_contain_cursor(bool may_contain_cursor) {
+    may_contain_cursor_ = may_contain_cursor;
+  }
+
+  // Time taken to capture the frame in milliseconds.
+  int64_t capture_time_ms() const { return capture_time_ms_; }
+  void set_capture_time_ms(int64_t time_ms) { capture_time_ms_ = time_ms; }
+
+  // Copies pixels from a buffer or another frame. `dest_rect` rect must lay
+  // within bounds of this frame.
+  void CopyPixelsFrom(const uint8_t* src_buffer,
+                      int src_stride,
+                      const DesktopRect& dest_rect);
+  void CopyPixelsFrom(const DesktopFrame& src_frame,
+                      const DesktopVector& src_pos,
+                      const DesktopRect& dest_rect);
+
+  // Copies pixels from another frame, with the copied & overwritten regions
+  // representing the intersection between the two frames. Returns true if
+  // pixels were copied, or false if there's no intersection. The scale factors
+  // represent the ratios between pixel space & offset coordinate space (e.g.
+  // 2.0 would indicate the frames are scaled down by 50% for display, so any
+  // offset between their origins should be doubled).
+  bool CopyIntersectingPixelsFrom(const DesktopFrame& src_frame,
+                                  double horizontal_scale,
+                                  double vertical_scale);
+
+  // A helper to return the data pointer of a frame at the specified position.
+  uint8_t* GetFrameDataAtPos(const DesktopVector& pos) const;
+
+  // The DesktopCapturer implementation which generates current DesktopFrame.
+  // Not all DesktopCapturer implementations set this field; it's set to
+  // kUnknown by default.
+  uint32_t capturer_id() const { return capturer_id_; }
+  void set_capturer_id(uint32_t capturer_id) { capturer_id_ = capturer_id; }
+
+  // Copies various information from `other`. Anything initialized in
+  // constructor are not copied.
+  // This function is usually used when sharing a source DesktopFrame with
+  // several clients: the original DesktopFrame should be kept unchanged. For
+  // example, BasicDesktopFrame::CopyOf() and SharedDesktopFrame::Share().
+  void CopyFrameInfoFrom(const DesktopFrame& other);
+
+  // Copies various information from `other`. Anything initialized in
+  // constructor are not copied. Not like CopyFrameInfoFrom() function, this
+  // function uses swap or move constructor to avoid data copy. It won't break
+  // the `other`, but some of its information may be missing after this
+  // operation. E.g. other->updated_region_;
+  // This function is usually used when wrapping a DesktopFrame: the wrapper
+  // instance takes the ownership of `other`, so other components cannot access
+  // `other` anymore. For example, CroppedDesktopFrame and
+  // DesktopFrameWithCursor.
+  void MoveFrameInfoFrom(DesktopFrame* other);
+
+  // Set and get the ICC profile of the frame data pixels. Useful to build the
+  // a ColorSpace object from clients of webrtc library like chromium. The
+  // format of an ICC profile is defined in the following specification
+  // http://www.color.org/specification/ICC1v43_2010-12.pdf.
+  const std::vector<uint8_t>& icc_profile() const { return icc_profile_; }
+  void set_icc_profile(const std::vector<uint8_t>& icc_profile) {
+    icc_profile_ = icc_profile;
+  }
+
+  // Sets all pixel values in the data buffer to zero.
+  void SetFrameDataToBlack();
+
+  // Returns true if all pixel values in the data buffer are zero or false
+  // otherwise. Also returns false if the frame is empty.
+  bool FrameDataIsBlack() const;
+
+ protected:
+  DesktopFrame(DesktopSize size,
+               int stride,
+               uint8_t* data,
+               SharedMemory* shared_memory);
+
+  // Ownership of the buffers is defined by the classes that inherit from this
+  // class. They must guarantee that the buffer is not deleted before the frame
+  // is deleted.
+  uint8_t* const data_;
+  SharedMemory* const shared_memory_;
+
+ private:
+  const DesktopSize size_;
+  const int stride_;
+
+  DesktopRegion updated_region_;
+  DesktopVector top_left_;
+  DesktopVector dpi_;
+  bool may_contain_cursor_ = false;
+  int64_t capture_time_ms_;
+  uint32_t capturer_id_;
+  std::vector<uint8_t> icc_profile_;
+};
+
+// A DesktopFrame that stores data in the heap.
+class RTC_EXPORT BasicDesktopFrame : public DesktopFrame {
+ public:
+  // The entire data buffer used for the frame is initialized with zeros.
+  explicit BasicDesktopFrame(DesktopSize size);
+
+  ~BasicDesktopFrame() override;
+
+  BasicDesktopFrame(const BasicDesktopFrame&) = delete;
+  BasicDesktopFrame& operator=(const BasicDesktopFrame&) = delete;
+
+  // Creates a BasicDesktopFrame that contains copy of `frame`.
+  // TODO(zijiehe): Return std::unique_ptr<DesktopFrame>
+  static DesktopFrame* CopyOf(const DesktopFrame& frame);
+};
+
+// A DesktopFrame that stores data in shared memory.
+class RTC_EXPORT SharedMemoryDesktopFrame : public DesktopFrame {
+ public:
+  // May return nullptr if `shared_memory_factory` failed to create a
+  // SharedMemory instance.
+  // `shared_memory_factory` should not be nullptr.
+  static std::unique_ptr<DesktopFrame> Create(
+      DesktopSize size,
+      SharedMemoryFactory* shared_memory_factory);
+
+  // Takes ownership of `shared_memory`.
+  // Deprecated, use the next constructor.
+  SharedMemoryDesktopFrame(DesktopSize size,
+                           int stride,
+                           SharedMemory* shared_memory);
+
+  // Preferred.
+  SharedMemoryDesktopFrame(DesktopSize size,
+                           int stride,
+                           std::unique_ptr<SharedMemory> shared_memory);
+
+  ~SharedMemoryDesktopFrame() override;
+
+  SharedMemoryDesktopFrame(const SharedMemoryDesktopFrame&) = delete;
+  SharedMemoryDesktopFrame& operator=(const SharedMemoryDesktopFrame&) = delete;
+
+ private:
+  // Avoid unexpected order of parameter evaluation.
+  // Executing both std::unique_ptr<T>::operator->() and
+  // std::unique_ptr<T>::release() in the member initializer list is not safe.
+  // Depends on the order of parameter evaluation,
+  // std::unique_ptr<T>::operator->() may trigger assertion failure if it has
+  // been evaluated after std::unique_ptr<T>::release(). By using this
+  // constructor, std::unique_ptr<T>::operator->() won't be involved anymore.
+  SharedMemoryDesktopFrame(DesktopRect rect,
+                           int stride,
+                           SharedMemory* shared_memory);
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_DESKTOP_CAPTURE_DESKTOP_FRAME_H_