# FFmpegForAndroid

**Repository Path**: RandB/FFmpegForAndroid

## Basic Information

- **Project Name**: FFmpegForAndroid
- **Description**: ffmpeg 的熟悉
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2020-12-23
- **Last Updated**: 2021-03-16

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

## FFMPEG Android 练习项目

>此项目目的在于练习FFMEG，借鉴 [字节流动/博客](https://blog.csdn.net/Kennethdroid/article/details/107103315)
 跟着博主的思路和流程来慢慢熟悉ffmpeg在音视频处理的流程和相应的API,在此表示感谢！

1.本项目 Kotlin 和 C++ 实现对FFmpeg 的调用


>记录问题
注意事项 c++ 调用kotlin 的函数， 函数签名与java 中的函数签名不一致，导致函数找不到问题。 
进入 app\build\tmp\kotlin-classess\debug\包名 运行javap -s xxx 命令查看类中的所有签名

举例：
```
Compiled from "NatureMediaPlayer.kt"
public final class com.nature.ffmpegforandroid.NatureMediaPlayer {
  public static final int VIDEO_GL_RENDER;
    descriptor: I
  public static final int AUDIO_GL_RENDER;
    descriptor: I
  public static final int VR_3D_GL_RENDER;
    descriptor: I
  public static final int MSG_DECODER_INIT_ERROR;
    descriptor: I
  public static final int MSG_DECODER_READY;
    descriptor: I
  public static final int MSG_DECODER_DONE;
    descriptor: I
  public static final int MSG_REQUEST_RENDER;
    descriptor: I
  public static final int MSG_DECODING_TIME;
    descriptor: I
  public static final int MEDIA_PARAM_VIDEO_WIDTH;
    descriptor: I
  public static final int MEDIA_PARAM_VIDEO_HEIGHT;
    descriptor: I
  public static final int MEDIA_PARAM_VIDEO_DURATION;
    descriptor: I
  public static final int VIDEO_RENDER_OPENGL;
    descriptor: I
  public static final int VIDEO_RENDER_ANWINDOW;
    descriptor: I
  public static final int VIDEO_RENDER_3D_VR;
    descriptor: I
  public static final com.nature.ffmpegforandroid.NatureMediaPlayer$Companion Companion;
    descriptor: Lcom/nature/ffmpegforandroid/NatureMediaPlayer$Companion;
  public final com.nature.ffmpegforandroid.NatureMediaPlayer$EventCallback getMEventCallback();
    descriptor: ()Lcom/nature/ffmpegforandroid/NatureMediaPlayer$EventCallback;

  public final void setMEventCallback(com.nature.ffmpegforandroid.NatureMediaPlayer$EventCallback);
    descriptor: (Lcom/nature/ffmpegforandroid/NatureMediaPlayer$EventCallback;)V

  public final void natureMediaPlayerInit(java.lang.String, int, android.view.Surface);
    descriptor: (Ljava/lang/String;ILandroid/view/Surface;)V

  public final void play();
    descriptor: ()V

  public final void pause();
    descriptor: ()V

  public final void seekToPosition(float);
    descriptor: (F)V

  public final void stop();
    descriptor: ()V

  public final void unInit();
    descriptor: ()V

  public final long getMediaParams(int);
    descriptor: (I)J

  public final kotlin.Unit playerEventCallback(int, float);
    descriptor: (IF)Lkotlin/Unit;

  public final native long native_get_media_param(long, int);
    descriptor: (JI)J

  public final native void native_un_init(long);
    descriptor: (J)V

  public final native void native_stop(long);
    descriptor: (J)V

  public final native void native_seek2_position(long, float);
    descriptor: (JF)V

  public final native void native_pause(long);
    descriptor: (J)V

  public final native long native_init(java.lang.String, int, android.view.Surface);
    descriptor: (Ljava/lang/String;ILandroid/view/Surface;)J

  public final native void native_play(long);
    descriptor: (J)V

  public final native void native_onsurface_created(int);
    descriptor: (I)V

  public final native void native_ondraw_frame(int);
    descriptor: (I)V

  public final native void native_onsurface_onchanged(int, int, int);
    descriptor: (III)V

  public com.nature.ffmpegforandroid.NatureMediaPlayer();
    descriptor: ()V

  static {};
    descriptor: ()V
}

```