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Question

我正在尝试在 Android 上使用 ffmpeg.so 我得到 Working Directory: null Environment: null error。

try {
    Process p = Runtime.getRuntime().exec("/data/data/com.example.foo/files/ffmpeg -f image2 -i "
+ Environment.getExternalStorageDirectory().getAbsolutePath() + "/img/b%d.jpg " 
+ Environment.getExternalStorageDirectory().getAbsolutePath() + "/DCIM/Camera/a444.mp4");   
} catch (IOException e) {
    e.printStackTrace();
}

错误日志

04-09 01:50:45.683: I/Adreno-EGL(18393): <qeglDrvAPI_eglInitialize:320>: EGL 1.4 QUALCOMM Build: I0404c4692afb8623f95c43aeb6d5e13ed4b30ddbDate: 11/06/13
04-09 01:50:45.713: D/OpenGLRenderer(18393): Enabling debug mode 0
04-09 01:53:56.487: D/dalvikvm(18551): Trying to load lib /data/app-lib/com.example.sodeneme-1/libffmpeg.so 0x423d7d00
04-09 01:53:56.487: D/dalvikvm(18551): Added shared lib /data/app-lib/com.example.sodeneme-1/libffmpeg.so 0x423d7d00
04-09 01:53:56.487: D/dalvikvm(18551): No JNI_OnLoad found in /data/app-lib/com.example.sodeneme-1/libffmpeg.so 0x423d7d00, skipping init
04-09 01:53:56.537: W/System.err(18551): java.io.IOException: Error running exec(). Command: [/data/data/com.example.sodeneme/files/ffmpeg, -f, image2, -i, /storage/emulated/0/img/b%d.jpg, /storage/emulated/0/DCIM/Camera/a444.mp4] Working Directory: null Environment: null
04-09 01:53:56.537: W/System.err(18551):    at java.lang.ProcessManager.exec(ProcessManager.java:211)
04-09 01:53:56.537: W/System.err(18551):    at java.lang.Runtime.exec(Runtime.java:173)
04-09 01:53:56.537: W/System.err(18551):    at java.lang.Runtime.exec(Runtime.java:246)
04-09 01:53:56.537: W/System.err(18551):    at java.lang.Runtime.exec(Runtime.java:189)
04-09 01:53:56.537: W/System.err(18551):    at com.example.sodeneme.MainActivity.onCreate(MainActivity.java:40)
04-09 01:53:56.537: W/System.err(18551):    at android.app.Activity.performCreate(Activity.java:5231)
04-09 01:53:56.537: W/System.err(18551):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
04-09 01:53:56.537: W/System.err(18551):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
04-09 01:53:56.537: W/System.err(18551):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
04-09 01:53:56.537: W/System.err(18551):    at android.app.ActivityThread.access$800(ActivityThread.java:135)
04-09 01:53:56.537: W/System.err(18551):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
04-09 01:53:56.537: W/System.err(18551):    at android.os.Handler.dispatchMessage(Handler.java:102)
04-09 01:53:56.537: W/System.err(18551):    at android.os.Looper.loop(Looper.java:136)
04-09 01:53:56.537: W/System.err(18551):    at android.app.ActivityThread.main(ActivityThread.java:5017)
04-09 01:53:56.537: W/System.err(18551):    at java.lang.reflect.Method.invokeNative(Native Method)
04-09 01:53:56.537: W/System.err(18551):    at java.lang.reflect.Method.invoke(Method.java:515)
04-09 01:53:56.537: W/System.err(18551):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
04-09 01:53:56.537: W/System.err(18551):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
04-09 01:53:56.537: W/System.err(18551):    at dalvik.system.NativeStart.main(Native Method)
04-09 01:53:56.547: W/System.err(18551): Caused by: java.io.IOException: No such file or directory
04-09 01:53:56.547: W/System.err(18551):    at java.lang.ProcessManager.exec(Native Method)
04-09 01:53:56.547: W/System.err(18551):    at java.lang.ProcessManager.exec(ProcessManager.java:209)
04-09 01:53:56.547: W/System.err(18551):    ... 18 more
04-09 01:53:56.577: I/Adreno-EGL(18551): <qeglDrvAPI_eglInitialize:320>: EGL 1.4 QUALCOMM Build: I0404c4692afb8623f95c43aeb6d5e13ed4b30ddbDate: 11/06/13
04-09 01:53:56.607: D/OpenGLRenderer(18551): Enabling debug mode 0

权限

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_INTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_INTERNAL_STORAGE" />
<uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />

Answer 1

也许您需要将此权限添加到您的 AndroidManifest.xml 文件：

android.permission.WRITE_EXTERNAL_STORAGE

Answer 2

您需要确保/data/data/com.example.foo/files/ffmpeg 文件具有正确的文件权限。

您可以使用以下命令检查文件权限：

String[] command = new String[]{"/system/bin/ls", "-l",
                                "/data/data/com.example.foo/files/ffmpeg" };
Process process = Runtime.getRuntime().exec(command);
BufferedReader reader = new BufferedReader(
                    new InputStreamReader(process.getInputStream()));
int read;

String output = "";

String line;
while ((line = reader.readLine()) != null) {
    output.concat(line + "\n");
    Log.w("myApp", "[[output]]:" + line);
}  
reader.close();
process.waitFor(); 

输出将是这样的（取决于实际权限，在这种情况下权限为 777）：

[[output]]:-rwxrwxrwx u0_a67   u0_a67     254460 2015-03-02 17:12 ffmpeg

您可以使用以下命令将权限设置为 744 ：

String[] command = new String[]{"/system/bin/chmod", "744",
                                "/data/data/com.example.foo/files/ffmpeg" };

如果您是从外部活动（比如说从服务）执行此命令，您的权限必须是 777（而不是 744）

Answer 3

我在使用 ffmpeg-android 项目时自发地遇到了同样的问题。我已经拥有了其他人提到的所有权限集，而且我过去没有遇到过这个问题。

我恢复到旧版本，它运行良好，然后重建最新版本，它再次正常 - 所以在我的情况下，解决方案是一个简单的 清理和重建..

如果你感到绝望，试试吧！

Answer 4

在我的情况下，您需要添加“sh -c”，如下例所示：

sh -c shellcommand  

希望对你有帮助。

大卫

Answer 5

你在执行命令之前缺少这个：

try {
            ffmpeg.loadBinary(new LoadBinaryResponseHandler() {

                @Override
                public void onStart() {}

                @Override
                public void onFailure() {}

                @Override
                public void onSuccess() {}

                @Override
                public void onFinish() {}
            });
        } catch (FFmpegNotSupportedException e) {
            // Handle if FFmpeg is not supported by device
        }

参考：http://writingminds.github.io/ffmpeg-android-java/