media/base/android/webaudio_media_codec_bridge.h

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef MEDIA_BASE_ANDROID_WEBAUDIO_MEDIA_CODEC_BRIDGE_H_
   6 #define MEDIA_BASE_ANDROID_WEBAUDIO_MEDIA_CODEC_BRIDGE_H_
   7
   8 #include <jni.h>
   9
  10 #include "base/file_descriptor_posix.h"
  11 #include "base/memory/shared_memory.h"
  12 #include "media/base/media_export.h"
  13
  14 namespace media {
  15
  16 // This class serves as a bridge for native code to call Java
  17 // functions in the Android MediaCodec class. See
  18 // http://developer.android.com/reference/android/media/MediaCodec.html.
  19 class MEDIA_EXPORT WebAudioMediaCodecBridge {
  20  public:
  21   // Create the bridge with the given file descriptors. We read from
  22   // |encoded_audio_handle| to get the encoded audio data. Audio file
  23   // information and decoded PCM samples are written to |pcm_output|.
  24   // We also take ownership of |pcm_output|.
  25   WebAudioMediaCodecBridge(base::SharedMemoryHandle encoded_audio_handle,
  26                            base::FileDescriptor pcm_output,
  27                            uint32_t data_size);
  28   ~WebAudioMediaCodecBridge();
  29
  30   // Inform JNI about this bridge. Returns true if registration
  31   // succeeded.
  32   static bool RegisterWebAudioMediaCodecBridge(JNIEnv* env);
  33
  34   // Start MediaCodec to process the encoded data in
  35   // |encoded_audio_handle|. The PCM samples are sent to |pcm_output|.
  36   static void RunWebAudioMediaCodec(
  37       base::SharedMemoryHandle encoded_audio_handle,
  38       base::FileDescriptor pcm_output,
  39       uint32_t data_size);
  40
  41   void OnChunkDecoded(JNIEnv* env,
  42                       jobject /*java object*/,
  43                       jobject buf,
  44                       jint buf_size,
  45                       jint input_channel_count,
  46                       jint output_channel_count);
  47
  48   void InitializeDestination(JNIEnv* env,
  49                              jobject /*java object*/,
  50                              jint channel_count,
  51                              jint sample_rate,
  52                              jlong duration_us);
  53
  54  private:
  55   // Handles MediaCodec processing of the encoded data in
  56   // |encoded_audio_handle_| and sends the pcm data to |pcm_output_|.
  57   // Returns true if decoding was successful.
  58   bool DecodeInMemoryAudioFile();
  59
  60   // Save encoded audio data to a temporary file and return the file
  61   // descriptor to that file.  -1 is returned if the audio data could
  62   // not be saved for any reason.
  63   int SaveEncodedAudioToFile(JNIEnv*, jobject);
  64
  65   // The encoded audio data is read from this file descriptor for the
  66   // shared memory that holds the encoded data.
  67   base::SharedMemoryHandle encoded_audio_handle_;
  68
  69   // The audio file information and decoded pcm data are written to
  70   // this file descriptor. We take ownership of this descriptor.
  71   int pcm_output_;
  72
  73   // The length of the encoded data.
  74   uint32_t data_size_;
  75
  76   DISALLOW_COPY_AND_ASSIGN(WebAudioMediaCodecBridge);
  77 };
  78
  79 }  // namespace media
  80 #endif  // MEDIA_BASE_ANDROID_WEBAUDIO_MEDIA_CODEC_BRIDGE_H_