如何通过中心裁剪和适合宽度/高度来适应动态壁纸中的视频？
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【中文标题】如何通过中心裁剪和适合宽度/高度来适应动态壁纸中的视频？【英文标题】：How to fit video in Live wallpaper, by center-crop and by fitting to width/height? 【发布时间】：2018-10-10 00:56:26 【问题描述】：背景
我正在制作可以显示视频的动态壁纸。一开始我认为这会很困难，所以有人建议使用 OpenGL 解决方案或其他非常复杂的解决方案（例如this one）。
无论如何，为此，我找到了很多地方在谈论它，并且基于这个github library（它有一些错误），我终于让它工作了。
问题
虽然我已成功显示视频，但与屏幕分辨率相比，我找不到控制视频显示方式的方法。
目前它总是被拉伸到屏幕大小，这意味着这个（视频取自here）：
显示如下：
原因是宽高比不同：560x320（视频分辨率）与 1080x1920（设备分辨率）。
注意：我很清楚各种 Github 存储库（例如 here）上提供的缩放视频解决方案，但我问的是动态壁纸。因此，它没有视图，因此它对如何做事有更多的限制。更具体地说，解决方案不能有任何类型的布局，TextureView 或 SurfaceView，或任何其他类型的 View。
我尝试过的
我尝试使用 SurfaceHolder 的各种字段和功能，但到目前为止没有运气。例子：
setVideoScalingMode - 它要么崩溃，要么什么都不做。
更改surfaceFrame - 相同。
这是我当前编写的代码（完整项目可用here）：
class MovieLiveWallpaperService : WallpaperService()
override fun onCreateEngine(): WallpaperService.Engine
return VideoLiveWallpaperEngine()
private enum class PlayerState
NONE, PREPARING, READY, PLAYING
inner class VideoLiveWallpaperEngine : WallpaperService.Engine()
private var mp: MediaPlayer? = null
private var playerState: PlayerState = PlayerState.NONE
override fun onSurfaceCreated(holder: SurfaceHolder)
super.onSurfaceCreated(holder)
Log.d("AppLog", "onSurfaceCreated")
mp = MediaPlayer()
val mySurfaceHolder = MySurfaceHolder(holder)
mp!!.setDisplay(mySurfaceHolder)
mp!!.isLooping = true
mp!!.setVolume(0.0f, 0.0f)
mp!!.setOnPreparedListener mp ->
playerState = PlayerState.READY
setPlay(true)
try
//mp!!.setDataSource(this@MovieLiveWallpaperService, Uri.parse("http://techslides.com/demos/sample-videos/small.mp4"))
mp!!.setDataSource(this@MovieLiveWallpaperService, Uri.parse("android.resource://" + packageName + "/" + R.raw.small))
catch (e: Exception)
override fun onDestroy()
super.onDestroy()
Log.d("AppLog", "onDestroy")
if (mp == null)
return
mp!!.stop()
mp!!.release()
playerState = PlayerState.NONE
private fun setPlay(play: Boolean)
if (mp == null)
return
if (play == mp!!.isPlaying)
return
when
!play ->
mp!!.pause()
playerState = PlayerState.READY
mp!!.isPlaying -> return
playerState == PlayerState.READY ->
Log.d("AppLog", "ready, so starting to play")
mp!!.start()
playerState = PlayerState.PLAYING
playerState == PlayerState.NONE ->
Log.d("AppLog", "not ready, so preparing")
mp!!.prepareAsync()
playerState = PlayerState.PREPARING
override fun onVisibilityChanged(visible: Boolean)
super.onVisibilityChanged(visible)
Log.d("AppLog", "onVisibilityChanged:" + visible + " " + playerState)
if (mp == null)
return
setPlay(visible)
class MySurfaceHolder(private val surfaceHolder: SurfaceHolder) : SurfaceHolder
override fun addCallback(callback: SurfaceHolder.Callback) = surfaceHolder.addCallback(callback)
override fun getSurface() = surfaceHolder.surface!!
override fun getSurfaceFrame() = surfaceHolder.surfaceFrame
override fun isCreating(): Boolean = surfaceHolder.isCreating
override fun lockCanvas(): Canvas = surfaceHolder.lockCanvas()
override fun lockCanvas(dirty: Rect): Canvas = surfaceHolder.lockCanvas(dirty)
override fun removeCallback(callback: SurfaceHolder.Callback) = surfaceHolder.removeCallback(callback)
override fun setFixedSize(width: Int, height: Int) = surfaceHolder.setFixedSize(width, height)
override fun setFormat(format: Int) = surfaceHolder.setFormat(format)
override fun setKeepScreenOn(screenOn: Boolean)
override fun setSizeFromLayout() = surfaceHolder.setSizeFromLayout()
override fun setType(type: Int) = surfaceHolder.setType(type)
override fun unlockCanvasAndPost(canvas: Canvas) = surfaceHolder.unlockCanvasAndPost(canvas)
问题
我想知道如何根据我们拥有的 ImageView 调整内容的比例，同时保持纵横比：
-
center-crop - 适合 100% 的容器（在本例中为屏幕），在需要时在侧面（顶部和底部或左侧和右侧）进行裁剪。不拉伸任何东西。这意味着内容看起来不错，但可能不会全部显示。
fit-center - 拉伸以适应宽度/高度
center-inside - 设置为原始大小，居中，只有在太大时才拉伸以适应宽度/高度。
【问题讨论】：
您是否尝试过使用 setFixedSize 将视频尺寸设置为表面支架 @SuhaibRoomy 出于某种原因，它给了我UnsupportedOperationException: Wallpapers currently only support sizing from layout。另外，我不知道用什么值来设置它。
您有一个视频，因此除非您编辑实际文件，否则您必须将其设置为在大小布局内播放。我认为 WallpaperService 不可能做到这一点。您尝试过 Daydream 吗？
@ChVas 我说的是动态壁纸。不是白日梦。此外，这是可能的。我见过其他动态壁纸可以做到这一点。
好的，几个小时后，基本上我得到的是一个关于做 fit-top、fit-center 或 fit-bottom 有多难的详细解释。稍后我仍然会试一试，但我认为现在你基本上坚持使用 fit-xy 和 center-crop。明天我会发布我到目前为止的内容，如果我找到一种合理的方法来获得另一种模式，我会更新。
【参考方案1】：
您可以使用 TextureView 来实现这一点。 （surfaceView 也不起作用）。我找到了一些代码可以帮助您实现这一目标。 在此演示中，您可以将视频裁剪为三种类型中心、顶部和底部。
TextureVideoView.java
public class TextureVideoView extends TextureView implements TextureView.SurfaceTextureListener
// Indicate if logging is on
public static final boolean LOG_ON = true;
// Log tag
private static final String TAG = TextureVideoView.class.getName();
private MediaPlayer mMediaPlayer;
private float mVideoHeight;
private float mVideoWidth;
private boolean mIsDataSourceSet;
private boolean mIsViewAvailable;
private boolean mIsVideoPrepared;
private boolean mIsPlayCalled;
private ScaleType mScaleType;
private State mState;
public enum ScaleType
CENTER_CROP, TOP, BOTTOM
public enum State
UNINITIALIZED, PLAY, STOP, PAUSE, END
public TextureVideoView(Context context)
super(context);
initView();
public TextureVideoView(Context context, AttributeSet attrs)
super(context, attrs);
initView();
public TextureVideoView(Context context, AttributeSet attrs, int defStyle)
super(context, attrs, defStyle);
initView();
private void initView()
initPlayer();
setScaleType(ScaleType.CENTER_CROP);
setSurfaceTextureListener(this);
public void setScaleType(ScaleType scaleType)
mScaleType = scaleType;
private void updateTextureViewSize()
float viewWidth = getWidth();
float viewHeight = getHeight();
float scaleX = 1.0f;
float scaleY = 1.0f;
if (mVideoWidth > viewWidth && mVideoHeight > viewHeight)
scaleX = mVideoWidth / viewWidth;
scaleY = mVideoHeight / viewHeight;
else if (mVideoWidth < viewWidth && mVideoHeight < viewHeight)
scaleY = viewWidth / mVideoWidth;
scaleX = viewHeight / mVideoHeight;
else if (viewWidth > mVideoWidth)
scaleY = (viewWidth / mVideoWidth) / (viewHeight / mVideoHeight);
else if (viewHeight > mVideoHeight)
scaleX = (viewHeight / mVideoHeight) / (viewWidth / mVideoWidth);
// Calculate pivot points, in our case crop from center
int pivotPointX;
int pivotPointY;
switch (mScaleType)
case TOP:
pivotPointX = 0;
pivotPointY = 0;
break;
case BOTTOM:
pivotPointX = (int) (viewWidth);
pivotPointY = (int) (viewHeight);
break;
case CENTER_CROP:
pivotPointX = (int) (viewWidth / 2);
pivotPointY = (int) (viewHeight / 2);
break;
default:
pivotPointX = (int) (viewWidth / 2);
pivotPointY = (int) (viewHeight / 2);
break;
Matrix matrix = new Matrix();
matrix.setScale(scaleX, scaleY, pivotPointX, pivotPointY);
setTransform(matrix);
private void initPlayer()
if (mMediaPlayer == null)
mMediaPlayer = new MediaPlayer();
else
mMediaPlayer.reset();
mIsVideoPrepared = false;
mIsPlayCalled = false;
mState = State.UNINITIALIZED;
/**
* @see MediaPlayer#setDataSource(String)
*/
public void setDataSource(String path)
initPlayer();
try
mMediaPlayer.setDataSource(path);
mIsDataSourceSet = true;
prepare();
catch (IOException e)
Log.d(TAG, e.getMessage());
/**
* @see MediaPlayer#setDataSource(Context, Uri)
*/
public void setDataSource(Context context, Uri uri)
initPlayer();
try
mMediaPlayer.setDataSource(context, uri);
mIsDataSourceSet = true;
prepare();
catch (IOException e)
Log.d(TAG, e.getMessage());
/**
* @see MediaPlayer#setDataSource(java.io.FileDescriptor)
*/
public void setDataSource(AssetFileDescriptor afd)
initPlayer();
try
long startOffset = afd.getStartOffset();
long length = afd.getLength();
mMediaPlayer.setDataSource(afd.getFileDescriptor(), startOffset, length);
mIsDataSourceSet = true;
prepare();
catch (IOException e)
Log.d(TAG, e.getMessage());
private void prepare()
try
mMediaPlayer.setOnVideoSizeChangedListener(
new MediaPlayer.OnVideoSizeChangedListener()
@Override
public void onVideoSizeChanged(MediaPlayer mp, int width, int height)
mVideoWidth = width;
mVideoHeight = height;
updateTextureViewSize();
);
mMediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener()
@Override
public void onCompletion(MediaPlayer mp)
mState = State.END;
log("Video has ended.");
if (mListener != null)
mListener.onVideoEnd();
);
// don't forget to call MediaPlayer.prepareAsync() method when you use constructor for
// creating MediaPlayer
mMediaPlayer.prepareAsync();
// Play video when the media source is ready for playback.
mMediaPlayer.setOnPreparedListener(new MediaPlayer.OnPreparedListener()
@Override
public void onPrepared(MediaPlayer mediaPlayer)
mIsVideoPrepared = true;
if (mIsPlayCalled && mIsViewAvailable)
log("Player is prepared and play() was called.");
play();
if (mListener != null)
mListener.onVideoPrepared();
);
catch (IllegalArgumentException e)
Log.d(TAG, e.getMessage());
catch (SecurityException e)
Log.d(TAG, e.getMessage());
catch (IllegalStateException e)
Log.d(TAG, e.toString());
/**
* Play or resume video. Video will be played as soon as view is available and media player is
* prepared.
*
* If video is stopped or ended and play() method was called, video will start over.
*/
public void play()
if (!mIsDataSourceSet)
log("play() was called but data source was not set.");
return;
mIsPlayCalled = true;
if (!mIsVideoPrepared)
log("play() was called but video is not prepared yet, waiting.");
return;
if (!mIsViewAvailable)
log("play() was called but view is not available yet, waiting.");
return;
if (mState == State.PLAY)
log("play() was called but video is already playing.");
return;
if (mState == State.PAUSE)
log("play() was called but video is paused, resuming.");
mState = State.PLAY;
mMediaPlayer.start();
return;
if (mState == State.END || mState == State.STOP)
log("play() was called but video already ended, starting over.");
mState = State.PLAY;
mMediaPlayer.seekTo(0);
mMediaPlayer.start();
return;
mState = State.PLAY;
mMediaPlayer.start();
/**
* Pause video. If video is already paused, stopped or ended nothing will happen.
*/
public void pause()
if (mState == State.PAUSE)
log("pause() was called but video already paused.");
return;
if (mState == State.STOP)
log("pause() was called but video already stopped.");
return;
if (mState == State.END)
log("pause() was called but video already ended.");
return;
mState = State.PAUSE;
if (mMediaPlayer.isPlaying())
mMediaPlayer.pause();
/**
* Stop video (pause and seek to beginning). If video is already stopped or ended nothing will
* happen.
*/
public void stop()
if (mState == State.STOP)
log("stop() was called but video already stopped.");
return;
if (mState == State.END)
log("stop() was called but video already ended.");
return;
mState = State.STOP;
if (mMediaPlayer.isPlaying())
mMediaPlayer.pause();
mMediaPlayer.seekTo(0);
/**
* @see MediaPlayer#setLooping(boolean)
*/
public void setLooping(boolean looping)
mMediaPlayer.setLooping(looping);
/**
* @see MediaPlayer#seekTo(int)
*/
public void seekTo(int milliseconds)
mMediaPlayer.seekTo(milliseconds);
/**
* @see MediaPlayer#getDuration()
*/
public int getDuration()
return mMediaPlayer.getDuration();
static void log(String message)
if (LOG_ON)
Log.d(TAG, message);
private MediaPlayerListener mListener;
/**
* Listener trigger 'onVideoPrepared' and `onVideoEnd` events
*/
public void setListener(MediaPlayerListener listener)
mListener = listener;
public interface MediaPlayerListener
public void onVideoPrepared();
public void onVideoEnd();
@Override
public void onSurfaceTextureAvailable(SurfaceTexture surfaceTexture, int width, int height)
Surface surface = new Surface(surfaceTexture);
mMediaPlayer.setSurface(surface);
mIsViewAvailable = true;
if (mIsDataSourceSet && mIsPlayCalled && mIsVideoPrepared)
log("View is available and play() was called.");
play();
@Override
public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width, int height)
@Override
public boolean onSurfaceTextureDestroyed(SurfaceTexture surface)
return false;
@Override
public void onSurfaceTextureUpdated(SurfaceTexture surface)
之后在 MainActivity.java
中使用这个类，就像下面的代码一样public class MainActivity extends AppCompatActivity implements View.OnClickListener,
ActionBar.OnNavigationListener
// Video file url
private static final String FILE_URL = "http://techslides.com/demos/sample-videos/small.mp4";
private TextureVideoView mTextureVideoView;
@Override
public void onCreate(Bundle savedInstanceState)
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
initActionBar();
if (!isWIFIOn(getBaseContext()))
Toast.makeText(getBaseContext(), "You need internet connection to stream video",
Toast.LENGTH_LONG).show();
private void initActionBar()
ActionBar actionBar = getSupportActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_LIST);
actionBar.setDisplayShowTitleEnabled(false);
SpinnerAdapter mSpinnerAdapter = ArrayAdapter.createFromResource(this, R.array.action_list,
android.R.layout.simple_spinner_dropdown_item);
actionBar.setListNavigationCallbacks(mSpinnerAdapter, this);
private void initView()
mTextureVideoView = (TextureVideoView) findViewById(R.id.cropTextureView);
findViewById(R.id.btnPlay).setOnClickListener(this);
findViewById(R.id.btnPause).setOnClickListener(this);
findViewById(R.id.btnStop).setOnClickListener(this);
@Override
public void onClick(View v)
switch (v.getId())
case R.id.btnPlay:
mTextureVideoView.play();
break;
case R.id.btnPause:
mTextureVideoView.pause();
break;
case R.id.btnStop:
mTextureVideoView.stop();
break;
final int indexCropCenter = 0;
final int indexCropTop = 1;
final int indexCropBottom = 2;
@Override
public boolean onNavigationItemSelected(int itemPosition, long itemId)
switch (itemPosition)
case indexCropCenter:
mTextureVideoView.stop();
mTextureVideoView.setScaleType(TextureVideoView.ScaleType.CENTER_CROP);
mTextureVideoView.setDataSource(FILE_URL);
mTextureVideoView.play();
break;
case indexCropTop:
mTextureVideoView.stop();
mTextureVideoView.setScaleType(TextureVideoView.ScaleType.TOP);
mTextureVideoView.setDataSource(FILE_URL);
mTextureVideoView.play();
break;
case indexCropBottom:
mTextureVideoView.stop();
mTextureVideoView.setScaleType(TextureVideoView.ScaleType.BOTTOM);
mTextureVideoView.setDataSource(FILE_URL);
mTextureVideoView.play();
break;
return true;
public static boolean isWIFIOn(Context context)
ConnectivityManager connMgr =
(ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo networkInfo = connMgr.getNetworkInfo(ConnectivityManager.TYPE_WIFI);
return (networkInfo != null && networkInfo.isConnected());
和布局 activity_main.xml 文件在下面
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_
android:layout_>
<com.example.videocropdemo.crop.TextureVideoView
android:id="@+id/cropTextureView"
android:layout_
android:layout_
android:layout_centerInParent="true" />
<LinearLayout
android:layout_
android:layout_
android:layout_alignParentBottom="true"
android:layout_margin="16dp"
android:orientation="horizontal">
<Button
android:id="@+id/btnPlay"
android:layout_
android:layout_
android:text="Play" />
<Button
android:id="@+id/btnPause"
android:layout_
android:layout_
android:text="Pause" />
<Button
android:id="@+id/btnStop"
android:layout_
android:layout_
android:text="Stop" />
</LinearLayout>
</RelativeLayout>
输出中心裁剪的代码看起来像
【讨论】：
这很好，但我在标题和描述中都特别写了，我对如何为动态壁纸做这件事很感兴趣。它没有任何视图。它甚至没有布局文件。【参考方案2】：所以我还不能得到你所要求的所有比例类型，但我已经能够使用 exo 播放器相当轻松地让 fit-xy 和 center-crop 工作。完整的代码可以在https://github.com/yperess/***/tree/50091878 看到，我会在我得到更多的时候更新它。最后，我还将填充 MainActivity 以允许您选择缩放类型作为设置（我将使用简单的 PreferenceActivity 执行此操作）并读取服务端的共享首选项值。
总体思路是，MediaCodec 已经实现了 fit-xy 和 center-crop，如果您可以访问视图层次结构，这实际上是您需要的仅有的两种模式。之所以如此，是因为 fit-center、fit-top、fit-bottom 都只是 fit-xy ，其中表面具有重力并被缩放以匹配视频大小 * 最小缩放。为了让这些工作我认为需要发生的是我们需要创建一个 OpenGL 上下文并提供一个 SurfaceTexture。这个 SurfaceTexture 可以用一个存根 Surface 包裹，可以传递给 exo 播放器。加载视频后，我们可以设置它们的大小，因为我们创建了它们。我们还在 SurfaceTexture 上有一个回调，让我们知道帧何时准备好。此时我们应该能够修改框架（希望只使用简单的矩阵缩放和变换）。
这里的关键组件是创建 exo 播放器：
private fun initExoMediaPlayer(): SimpleExoPlayer
val videoTrackSelectionFactory = AdaptiveTrackSelection.Factory(bandwidthMeter)
val trackSelector = DefaultTrackSelector(videoTrackSelectionFactory)
val player = ExoPlayerFactory.newSimpleInstance(this@MovieLiveWallpaperService,
trackSelector)
player.playWhenReady = true
player.repeatMode = Player.REPEAT_MODE_ONE
player.volume = 0f
if (mode == Mode.CENTER_CROP)
player.videoScalingMode = C.VIDEO_SCALING_MODE_SCALE_TO_FIT_WITH_CROPPING
else
player.videoScalingMode = C.VIDEO_SCALING_MODE_SCALE_TO_FIT
if (mode == Mode.FIT_CENTER)
player.addVideoListener(this)
return player
然后加载视频：
override fun onSurfaceCreated(holder: SurfaceHolder)
super.onSurfaceCreated(holder)
if (mode == Mode.FIT_CENTER)
// We need to somehow wrap the surface or set some scale factor on exo player here.
// Most likely this will require creating a SurfaceTexture and attaching it to an
// OpenGL context. Then for each frame, writing it to the original surface but with
// an offset
exoMediaPlayer.setVideoSurface(holder.surface)
else
exoMediaPlayer.setVideoSurfaceHolder(holder)
val videoUri = RawResourceDataSource.buildRawResourceUri(R.raw.small)
val dataSourceFactory = DataSource.Factory RawResourceDataSource(context)
val mediaSourceFactory = ExtractorMediaSource.Factory(dataSourceFactory)
exoMediaPlayer.prepare(mediaSourceFactory.createMediaSource(videoUri))
更新：
得到它的工作，我需要明天在发布代码之前清理它，但这里有一个预览......
我最终所做的基本上是采用 GLSurfaceView 并将其撕开。如果您查看它的源代码，那么唯一无法在墙纸中使用的是它仅在附加到窗口时才启动 GLThread 的事实。因此，如果您复制相同的代码但允许手动启动 GLThread，您可以继续。之后，您只需在缩放到适合的最小比例并将您绘制到的四边形移动到之后，跟踪您的屏幕与视频的大小。
代码的已知问题：
1. GLThread 有个小bug，一直没能解决。似乎有一个简单的时间问题，当线程暂停时，我接到了对 signallAll() 的调用，实际上并没有在等待任何东西。
2.我没有费心在渲染器中动态修改模式。应该不会太难。在创建引擎时添加首选项监听器，然后在 scale_type 更改时更新渲染器。
更新：
所有问题都已解决。 signallAll() 正在抛出，因为我错过了检查我们是否确实拥有锁。我还添加了一个监听器来动态更新比例类型，所以现在所有比例类型都使用 GlEngine。
尽情享受吧！
【讨论】：
是的，这也是我在 ExoPlayer 的 Github 上与他们交谈时得到的：github.com/google/ExoPlayer/issues/4457。但是为什么一些应用程序成功地以其他方式显示视频缩放？ 是的，在 open gl 中都是手动的。我正在研究那部分，只是还没有真正做到。准备好后我会提交并更新答案 等等，你得到了哪些缩放类型？ 目前实现的是中心裁剪（保持纵横比，两个边缘 >= 到屏幕）和适合 XY（两个边缘 == 屏幕，失去纵横比），我仍在研究 fit-center这将保持纵横比，但填充高度/宽度并使视频居中，这应该与我可能会实现 fit-bottom 和 fit-top 的地方足够相似。我会努力完成它，但我明天早上要去带我女儿徒步旅行 5 天，所以我们会看看我是否能按时完成。无论如何，我会解决这个问题的:) 但是 fixXY 是我得到的，几乎从来没有真正使用过......你将如何做 fit-center？【参考方案3】：我找到这篇文章：How to set video as live wallpaper and keep video aspect ratio(width and height)
以上文章来源简单，只需点击“设置壁纸”按钮，如果您想要全功能应用，请参阅https://github.com/AlynxZhou/alynx-live-wallpaper
关键是用glsurfaceview代替wallpaperservice默认surfaceview，制作自定义glsurfaceview渲染器，glsurfaceview可以用opengl显示，所以问题变成“如何使用glsurfaceview播放视频”或“如何使用opengl播放视频”
如何使用glsurfaceview代替wallpaperservice默认surfaceview：
public class GLWallpaperService extends WallpaperService
...
class GLWallpaperEngine extends Engine
...
private class GLWallpaperSurfaceView extends GLSurfaceView
@SuppressWarnings("unused")
private static final String TAG = "GLWallpaperSurface";
public GLWallpaperSurfaceView(Context context)
super(context);
/**
* This is a hack. Because Android Live Wallpaper only has a Surface.
* So we create a GLSurfaceView, and when drawing to its Surface,
* we replace it with WallpaperEngine's Surface.
*/
@Override
public SurfaceHolder getHolder()
return getSurfaceHolder();
void onDestroy()
super.onDetachedFromWindow();
【讨论】：
你能分享一下它的完整代码吗？由于某种原因我无法到达它 @androiddeveloper 见github.com/AlynxZhou/alynx-live-wallpaper 这很好，但似乎比我问的要多得多。我只是问了一个具体的事情。你能至少指出我应该看的部分吗？或者编写一个最小的应用程序来演示它并在这里发布？对不起，如果这听起来很粗鲁。我已经给你+1了。希望没事。 @androiddeveloper 看到这个文件：github.com/AlynxZhou/alynx-live-wallpaper/blob/master/app/src/…，这是壁纸服务，它使用exoplayer，将exoplayer的视频源更改为你的视频，并将这个壁纸服务设置为动态壁纸，抱歉我不知道如何使用opengl 但我确信这个 repo 有效 是的，我知道它有效。只是希望有一个更简单的解决方案。总有一天我会检查的。对不起，谢谢。【参考方案4】：我的解决方案是在动态壁纸中使用 gif（大小和 fps 与视频相同）而不是视频
看我的回答：https://***.com/a/60425717/6011193，WallpaperService 最适合 gif
使用 ffmpeg 将计算机中的视频转换为 gif
或者在android中，视频可以在android代码中转成gif：见https://***.com/a/16749143/6011193
【讨论】：
GIF 在性能和大小上都被认为效率较低。动画 WEBP 也是如此【参考方案5】：您可以使用Glide 进行 GIF 和图像加载，并根据需要提供缩放选项。基于文档https://bumptech.github.io/glide/doc/targets.html#sizes-and-dimensions 和https://futurestud.io/tutorials/glide-image-resizing-scaling 这个。
Glide v4 需要 Android Ice Cream Sandwich（API 级别 14）或更高版本。
点赞：
public static void loadCircularImageGlide(String imagePath, ImageView view)
Glide.with(view.getContext())
.load(imagePath)
.asGif()
.override(600, 200) // resizes the image to these dimensions (in pixel). resize does not respect aspect ratio
.error(R.drawable.create_timeline_placeholder)
.fitCenter() // scaling options
.transform(new CircularTransformation(view.getContext())) // Even you can Give image tranformation too
.into(view);
【讨论】：
我已经意识到了这一点，但是这一次，这里没有视图。这是一个动态壁纸。请展示如何为动态壁纸执行此操作。请提供完整的代码，正如我所展示的那样。 @androiddeveloper 如果您需要完整代码，那么您需要与我分享您的代码。 完整的代码从一开始就一直可用。请检查链接。从昨天开始，它甚至在 Github 上。 另外，问题是关于视频，而不是 GIF以上是关于如何通过中心裁剪和适合宽度/高度来适应动态壁纸中的视频？的主要内容，如果未能解决你的问题，请参考以下文章