我已经在Android上编译了FFmpeg (libffmpeg.so)。现在我必须构建一个应用程序，如RockPlayer或使用现有的Android多媒体框架来调用FFmpeg。
你有在Android / StageFright上集成FFmpeg的步骤/过程/代码/示例吗? 你能指导我如何使用这个库来播放多媒体吗? 我有一个需求，我已经有音频和视频传输流，我需要将其馈送到FFmpeg并将其解码/渲染。我怎么能在Android上做到这一点，因为IOMX api是基于OMX的，不能在这里插件FFmpeg ? 我也找不到FFmpeg api的文档，需要用于回放。
以下是我在让ffmpeg在Android上工作时所经历的步骤:
Build static libraries of ffmpeg for Android. This was achieved by building olvaffe's ffmpeg android port (libffmpeg) using the Android Build System. Simply place the sources under /external and make away. You'll need to extract bionic(libc) and zlib(libz) from the Android build as well, as ffmpeg libraries depend on them. Create a dynamic library wrapping ffmpeg functionality using the Android NDK. There's a lot of documentation out there on how to work with the NDK. Basically you'll need to write some C/C++ code to export the functionality you need out of ffmpeg into a library java can interact with through JNI. The NDK allows you to easily link against the static libraries you've generated in step 1, just add a line similar to this to Android.mk: LOCAL_STATIC_LIBRARIES := libavcodec libavformat libavutil libc libz Use the ffmpeg-wrapping dynamic library from your java sources. There's enough documentation on JNI out there, you should be fine.
关于使用ffmpeg进行回放，有很多例子(ffmpeg二进制本身就是一个很好的例子)，这里是一个基本教程。最好的文档可以在标题中找到。
祝你好运。
我做了一个小项目，使用Android NDK配置和构建X264和FFMPEG。主要缺少的是一个像样的JNI接口，可以通过Java访问它，但这是比较容易的部分(相对而言)。当我腾出时间使JNI接口适合我自己使用时，我将把它推进去。
与olvaffe的构建系统相比，它的优势在于不需要Android。Mk文件来构建库，它只使用常规的makefiles和工具链。这使得当你从FFMPEG或X264中做出新的改变时，它不太可能停止工作。
https://github.com/halfninja/android-ffmpeg-x264
由于各种原因，多媒体在不影响效率的情况下完成任务从来都不容易。Ffmpeg每天都在努力改进它。它支持不同格式的编解码器和容器。
现在要回答如何使用这个库的问题，我想说在这里编写它并不是那么简单。但我可以用以下方法指导你。
1)在源代码的ffmpeg目录中，有output_example.c或api_example.c。在这里，您可以看到编码/解码完成的代码。您将了解应该在ffmpeg中调用哪个API。这是你的第一步。
2) Dolphin player是一个面向Android的开源项目。目前它有bug，但开发人员正在持续工作。在该项目中，您已经准备好了整个设置，您可以使用它继续您的调查。这里有一个来自code.google.com的项目链接，或者在终端中运行命令“git clone https://code.google.com/p/dolphin-player/”。您可以看到两个名为P和P86的项目。你可以用它们中的任何一个。
我想提供的额外提示是，当您构建ffmpeg代码时，在build.sh中，您需要启用您想使用的格式的muxers/demuxers/编码器/解码器。否则相应的代码将不包含在库中。我花了很长时间才意识到这一点。所以我想和你分享。
基本要素: 当我们说一个视频文件，例如:avi，它是音频和视频的组合
视频文件=视频+音频
视频=编解码器+ Muxer + Demuxer
codec =编码器+解码器
=>视频=编码器+解码器+ Muxer + Demuxer(Mpeg4 + Mpeg4 +avi +avi - avi容器的示例)
音频=编解码器+ Muxer + Demuxer
codec =编码器+解码器
=>音频=编码器+解码器+ Muxer + Demuxer(mp2 + mp2 + avi + avi - avi容器示例)
编解码器(名称来源于en*co*der/*dec*oder的组合)只是格式的一部分，它定义了用于编码/解码帧的算法。AVI不是一个编解码器，它是一个使用Mpeg4的视频编解码器和mp2的音频编解码器的容器。
Muxer/demuxer用于在编码/解码时从文件中合并/分离帧。
所以如果你想使用avi格式，你需要启用视频组件+音频组件。
Ex，对于avi，您需要启用以下功能。 mpeg4编码器，mpeg4解码器，mp2编码器，mp2解码器，avi muxer, avi demuxer。
噗嗤...
以编程方式build.sh应该包含以下代码:
--enable-muxer=avi --enable-demuxer=avi (Generic for both audio/video. generally Specific to a container)
--enable-encoder=mpeg4 --enable-decoder=mpeg4(For video support)
--enable-encoder=mp2 --enable-decoder=mp2 (For Audio support)
希望在这之后我没有让你更困惑…
谢谢，需要任何帮助，请告诉我。
我发现最容易构建、最容易使用的实现是由guardianproject团队制作的:https://github.com/guardianproject/android-ffmpeg
受到Android上其他FFmpeg实现(主要是guadianproject)的启发，我找到了一个解决方案(也有Lame支持)。
(lame和FFmpeg: https://github.com/intervigilium/liblame和http://bambuser.com/opensource)
调用FFmpeg:
new Thread(new Runnable() {
@Override
public void run() {
Looper.prepare();
FfmpegController ffmpeg = null;
try {
ffmpeg = new FfmpegController(context);
} catch (IOException ioe) {
Log.e(DEBUG_TAG, "Error loading ffmpeg. " + ioe.getMessage());
}
ShellDummy shell = new ShellDummy();
String mp3BitRate = "192";
try {
ffmpeg.extractAudio(in, out, audio, mp3BitRate, shell);
} catch (IOException e) {
Log.e(DEBUG_TAG, "IOException running ffmpeg" + e.getMessage());
} catch (InterruptedException e) {
Log.e(DEBUG_TAG, "InterruptedException running ffmpeg" + e.getMessage());
}
Looper.loop();
}
}).start();
并处理控制台输出:
private class ShellDummy implements ShellCallback {
@Override
public void shellOut(String shellLine) {
if (someCondition) {
doSomething(shellLine);
}
Utils.logger("d", shellLine, DEBUG_TAG);
}
@Override
public void processComplete(int exitValue) {
if (exitValue == 0) {
// Audio job OK, do your stuff:
// i.e.
// write id3 tags,
// calls the media scanner,
// etc.
}
}
@Override
public void processNotStartedCheck(boolean started) {
if (!started) {
// Audio job error, as above.
}
}
}
为了使我的FFMPEG应用程序，我使用了这个项目(https://github.com/hiteshsondhi88/ffmpeg-android-java)，所以，我不需要编译任何东西。我认为这是在我们的Android应用程序中使用FFMPEG的简单方法。
更多信息http://hiteshsondhi88.github.io/ffmpeg-android-java/
我也有同样的问题，我发现这里的大多数答案都过时了。 我最终在FFMPEG上编写了一个包装器，用一行代码从Android访问。
https://github.com/madhavanmalolan/ffmpegandroidlibrary
经过大量的研究，现在这是我发现的最新的Android编译库:
https://github.com/bravobit/FFmpeg-Android
目前使用的是FFmpeg版本n4.0-39-gda39990 包括FFmpeg和FFProbe 包含用于启动命令的Java接口 FFprobe或FFmpeg可以从APK中删除，检查维基https://github.com/bravobit/FFmpeg-Android/wiki
首先，添加FFmpeg库的依赖项
implementation 'com.writingminds:FFmpegAndroid:0.3.2'
然后载入活动
FFmpeg ffmpeg;
private void trimVideo(ProgressDialog progressDialog) {
outputAudioMux = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MOVIES).getAbsolutePath()
+ "/VidEffectsFilter" + "/" + new SimpleDateFormat("ddMMyyyy_HHmmss").format(new Date())
+ "filter_apply.mp4";
if (startTrim.equals("")) {
startTrim = "00:00:00";
}
if (endTrim.equals("")) {
endTrim = timeTrim(player.getDuration());
}
String[] cmd = new String[]{"-ss", startTrim + ".00", "-t", endTrim + ".00", "-noaccurate_seek", "-i", videoPath, "-codec", "copy", "-avoid_negative_ts", "1", outputAudioMux};
execFFmpegBinary1(cmd, progressDialog);
}
private void execFFmpegBinary1(final String[] command, ProgressDialog prpg) {
ProgressDialog progressDialog = prpg;
try {
ffmpeg.execute(command, new ExecuteBinaryResponseHandler() {
@Override
public void onFailure(String s) {
progressDialog.dismiss();
Toast.makeText(PlayerTestActivity.this, "Fail to generate video", Toast.LENGTH_SHORT).show();
Log.d(TAG, "FAILED with output : " + s);
}
@Override
public void onSuccess(String s) {
Log.d(TAG, "SUCCESS wgith output : " + s);
// pathVideo = outputAudioMux;
String finalPath = outputAudioMux;
videoPath = outputAudioMux;
Toast.makeText(PlayerTestActivity.this, "Storage Path =" + finalPath, Toast.LENGTH_SHORT).show();
Intent intent = new Intent(PlayerTestActivity.this, ShareVideoActivity.class);
intent.putExtra("pathGPU", finalPath);
startActivity(intent);
finish();
MediaScannerConnection.scanFile(PlayerTestActivity.this, new String[]{finalPath}, new String[]{"mp4"}, null);
}
@Override
public void onProgress(String s) {
Log.d(TAG, "Started gcommand : ffmpeg " + command);
progressDialog.setMessage("Please Wait video triming...");
}
@Override
public void onStart() {
Log.d(TAG, "Startedf command : ffmpeg " + command);
}
@Override
public void onFinish() {
Log.d(TAG, "Finished f command : ffmpeg " + command);
progressDialog.dismiss();
}
});
} catch (FFmpegCommandAlreadyRunningException e) {
// do nothing for now
}
}
private void loadFFMpegBinary() {
try {
if (ffmpeg == null) {
ffmpeg = FFmpeg.getInstance(this);
}
ffmpeg.loadBinary(new LoadBinaryResponseHandler() {
@Override
public void onFailure() {
showUnsupportedExceptionDialog();
}
@Override
public void onSuccess() {
Log.d("dd", "ffmpeg : correct Loaded");
}
});
} catch (FFmpegNotSupportedException e) {
showUnsupportedExceptionDialog();
} catch (Exception e) {
Log.d("dd", "EXception no controlada : " + e);
}
}
private void showUnsupportedExceptionDialog() {
new AlertDialog.Builder(this)
.setIcon(android.R.drawable.ic_dialog_alert)
.setTitle("Not Supported")
.setMessage("Device Not Supported")
.setCancelable(false)
.setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
finish();
}
})
.create()
.show();
}
public String timeTrim(long milliseconds) {
String finalTimerString = "";
String minutString = "";
String secondsString = "";
// Convert total duration into time
int hours = (int) (milliseconds / (1000 * 60 * 60));
int minutes = (int) (milliseconds % (1000 * 60 * 60)) / (1000 * 60);
int seconds = (int) ((milliseconds % (1000 * 60 * 60)) % (1000 * 60) / 1000);
// Add hours if there
if (hours < 10) {
finalTimerString = "0" + hours + ":";
} else {
finalTimerString = hours + ":";
}
if (minutes < 10) {
minutString = "0" + minutes;
} else {
minutString = "" + minutes;
}
// Prepending 0 to seconds if it is one digit
if (seconds < 10) {
secondsString = "0" + seconds;
} else {
secondsString = "" + seconds;
}
finalTimerString = finalTimerString + minutString + ":" + secondsString;
// return timer string
return finalTimerString;
}
也可以使用FFmpeg的另一个特性
===> merge audio to video
String[] cmd = new String[]{"-i", yourRealPath, "-i", arrayList.get(posmusic).getPath(), "-map", "1:a", "-map", "0:v", "-codec", "copy", "-shortest", outputcrop};
===> Flip vertical :
String[] cm = new String[]{"-i", yourRealPath, "-vf", "vflip", "-codec:v", "libx264", "-preset", "ultrafast", "-codec:a", "copy", outputcrop1};
===> Flip horizontally :
String[] cm = new String[]{"-i", yourRealPath, "-vf", "hflip", "-codec:v", "libx264", "-preset", "ultrafast", "-codec:a", "copy", outputcrop1};
===> Rotate 90 degrees clockwise:
String[] cm=new String[]{"-i", yourRealPath, "-c", "copy", "-metadata:s:v:0", "rotate=90", outputcrop1};
===> Compress Video
String[] complexCommand = {"-y", "-i", yourRealPath, "-strict", "experimental", "-vcodec", "libx264", "-preset", "ultrafast", "-crf", "24", "-acodec", "aac", "-ar", "22050", "-ac", "2", "-b", "360k", "-s", "1280x720", outputcrop1};
===> Speed up down video
String[] complexCommand = {"-y", "-i", yourRealPath, "-filter_complex", "[0:v]setpts=2.0*PTS[v];[0:a]atempo=0.5[a]", "-map", "[v]", "-map", "[a]", "-b:v", "2097k", "-r", "60", "-vcodec", "mpeg4", outputcrop1};
String[] complexCommand = {"-y", "-i", yourRealPath, "-filter_complex", "[0:v]setpts=1.0*PTS[v];[0:a]atempo=1.0[a]", "-map", "[v]", "-map", "[a]", "-b:v", "2097k", "-r", "60", "-vcodec", "mpeg4", outputcrop1};
String[] complexCommand = {"-y", "-i", yourRealPath, "-filter_complex", "[0:v]setpts=0.75*PTS[v];[0:a]atempo=1.5[a]", "-map", "[v]", "-map", "[a]", "-b:v", "2097k", "-r", "60", "-vcodec", "mpeg4", outputcrop1};
String[] complexCommand = {"-y", "-i", yourRealPath, "-filter_complex", "[0:v]setpts=0.5*PTS[v];[0:a]atempo=2.0[a]", "-map", "[v]", "-map", "[a]", "-b:v", "2097k", "-r", "60", "-vcodec", "mpeg4", outputcrop1};
===> Add two mp3 files
StringBuilder sb = new StringBuilder();
sb.append("-i ");
sb.append(textSngname);
sb.append(" -i ");
sb.append(mAudioFilename);
sb.append(" -filter_complex [0:0][1:0]concat=n=2:v=0:a=1[out] -map [out] ");
sb.append(finalfile);
---> ffmpeg.execute(sb.toString().split(" "), new ExecuteBinaryResponseHandler()
===> Add three mp3 files
StringBuilder sb = new StringBuilder();
sb.append("-i ");
sb.append(firstSngname);
sb.append(" -i ");
sb.append(textSngname);
sb.append(" -i ");
sb.append(mAudioFilename);
sb.append(" -filter_complex [0:0][1:0][2:0]concat=n=3:v=0:a=1[out] -map [out] ");
sb.append(finalfile);
---> ffmpeg.execute(sb.toString().split(" "), new ExecuteBinaryResponseHandler()
