Add ArcGpuVideoDecodeAccelerator.

chrome/gpu/arc_video_accelerator.h

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_GPU_ARC_VIDEO_ACCELERATOR_H_
+#define CHROME_GPU_ARC_VIDEO_ACCELERATOR_H_
+
+namespace chromeos {
+namespace arc {
+
+enum HalPixelFormatExtension {
+  HAL_PIXEL_FORMAT_H264 = 0x34363248,
+  HAL_PIXEL_FORMAT_VP8 = 0x00385056,
+};
+
+enum PortType {
+  PORT_INPUT = 0,
+  PORT_OUTPUT = 1,
+  PORT_COUNT = 2,
+};
+
+enum BufferFlag {
+  BUFFER_FLAG_EOS = 1 << 0,
+};
+
+struct BufferMetadata {
+  int64_t timestamp = 0;  // in microseconds
+  uint32_t flags = 0;     // Flags defined in BufferFlag.
+  uint32_t bytes_used = 0;
+};
+
+struct VideoFormat {
+  uint32_t pixel_format = 0;
+  uint32_t buffer_size = 0;
+
+  // Minimal number of buffers required to decode/encode the stream.

[Pawel Osciak, 2016/03/25 08:38:45]

s/Minimal/Minimum/

[Owen Lin, 2016/03/29 07:10:41]

Done.

+  uint32_t min_num_buffers = 0;
+  uint32_t coded_width = 0;
+  uint32_t coded_height = 0;
+  uint32_t crop_left = 0;
+  uint32_t crop_width = 0;
+  uint32_t crop_top = 0;
+  uint32_t crop_height = 0;
+};
+
+class ArcVideoAccelerator {

[Pawel Osciak, 2016/03/25 08:38:45]

We should still have some comment what this class is...

[Owen Lin, 2016/03/29 07:10:42]

Done.

+ public:
+  enum Error {
+    ILLEGAL_STATE = 1,
+    INVALID_ARGUMENT = 2,
+    UNREADABLE_INPUT = 3,
+    PLATFORM_FAILURE = 4,
+  };
+
+  struct Config {
+    enum DeviceType {
+      DEVICE_ENCODER = 0,
+      DEVICE_DECODER = 1,
+    };
+
+    DeviceType device_type = DEVICE_DECODER;
+    size_t num_input_buffers = 0;
+    uint32_t input_pixel_format = 0;
+    // TODO(owenlin): Add output_pixel_format. For now only the native pixel
+    //                format of each VDA on Chromium is supported.
+  };
+
+  // The callbacks of the ArcVideoAccelerator. The user of this class should
+  // implement this interface.
+  class Client {
+   public:
+    virtual ~Client() {}
+
+    // Called when an asynchronous error happens. The errors in Initialize()
+    // will not be reported here, but will be indicated by a false return value
+    // there.
+    virtual void OnError(Error error) = 0;
+
+    // Called when a buffer with the specified |index| and |port| has been
+    // processed and is no longer used in the accelerator. For input buffers,
+    // the Client may fill them with new content. For output buffers, indicates
+    // they are ready to be consumed by the client.
+    virtual void OnBufferDone(PortType port,
+                              uint32_t index,
+                              const BufferMetadata& metadata) = 0;
+
+    // Called when the output format has changed or the output format
+    // becomes available at beginning of the stream after initial parsing.
+    virtual void OnOutputFormatChanged(const VideoFormat& format) = 0;
+
+    // Called as a completion notification for Reset().
+    virtual void OnResetDone() = 0;
+  };
+
+  // Initializes the ArcVideoAccelerator with specific configuration. This
+  // must be called before any other methods. This call is synchronous and
+  // returns true iff initialization is successful.
+  virtual bool Initialize(const Config& config, Client* client) = 0;
+
+  // Assigns a shared memory to be used for the accelerator at the specified
+  // port and index. A buffer must be successfully bound before it can be passed
+  // to the accelerator via UseBuffer(). Already bound buffers may be reused
+  // multiple times without additional bindings.
+  virtual void BindSharedMemory(PortType port,
+                                uint32_t index,
+                                int ashmem_fd,
+                                off_t offset,
+                                size_t length) = 0;
+
+  // Assigns a buffer to be used for the accelerator at the specified
+  // port and index. A buffer must be successfully bound before it can be
+  // passed to the accelerator via UseBuffer. Already bound buffers may be
+  // resued multiple times without additional bindings.
+  virtual void BindDmabuf(PortType port, uint32_t index, int dmabuf_fd) = 0;
+
+  // Passes a buffer to the accelerator. For input buffer, the accelerator
+  // will process it. For output buffer, the accelerator will output content
+  // to it.
+  virtual void UseBuffer(PortType port,
+                         uint32_t index,
+                         const BufferMetadata& metadata) = 0;
+
+  // Sets the number of output buffers. When it fails, Client::OnError() will
+  // be called.
+  virtual void SetNumberOfOutputBuffers(size_t number) = 0;
+
+  // Resets the accelerator. When it is done, Client::OnResetDone() will
+  // be called. Afterwords, all buffers won't be accessed by the accelerator

[Pawel Osciak, 2016/03/25 08:38:45]

s/Afterwords/Afterwards/

[Owen Lin, 2016/03/29 07:10:41]

Done.

+  // and there won't be more callbacks.
+  virtual void Reset() = 0;
+
+  virtual ~ArcVideoAccelerator() {}
+};
+
+}  // namespace arc
+}  // namespace chromeos
+
+#endif  // CHROME_GPU_ARC_VIDEO_ACCELERATOR_H_