Android：是不是可以显示视频缩略图？
Posted
技术标签:
【中文标题】Android：是不是可以显示视频缩略图？【英文标题】：Android: Is it possible to display video thumbnails?Android：是否可以显示视频缩略图？ 【发布时间】：2010-11-23 00:15:47 【问题描述】：我创建了一个带有库对话框的视频录制应用程序。库对话框显示录制的视频列表，其中每个项目由图标、视频标题、标签和位置信息组成，方式如下：
有谁知道是否可以用视频缩略图替换图标（单帧预览）？
谢谢！
【问题讨论】：
任何一个答案 [***.com/questions/16190374/… 【参考方案1】：如果您没有或不能通过光标，并且您只有路径或文件对象，则可以从 API 级别 8 (2.2) 开始使用 public static Bitmap createVideoThumbnail(String filePath, int kind)
android documentation
以下代码运行完美：
Bitmap bMap = ThumbnailUtils.createVideoThumbnail(file.getAbsolutePath(), MediaStore.Video.Thumbnails.MICRO_KIND);
【讨论】：
当我尝试创建缩略图时，我得到空值。我觉得我的路可能不太好？ myPath ="/external/video/media/14180" 它就像魔术一样工作。即使我不t have my video ID. For better quality use MediaStore.Video.Thumbnails.FULL_SCREEN_KIND`
奇怪，它也不起作用 ;-( 视频存在于数据库中，我可以检索名称/大小，但不能检索缩略图
haythem souussi 因为这不是路径这是 Uri，您需要将其转换为路径。
'createVideoThumbnail(java.lang.String, int)' 已弃用【参考方案2】：
如果您使用的是 API 2.0 或更新版本，这将起作用。
int id = **"The Video's ID"**
ImageView iv = (ImageView ) convertView.findViewById(R.id.imagePreview);
ContentResolver crThumb = getContentResolver();
BitmapFactory.Options options=new BitmapFactory.Options();
options.inSampleSize = 1;
Bitmap curThumb = MediaStore.Video.Thumbnails.getThumbnail(crThumb, id, MediaStore.Video.Thumbnails.MICRO_KIND, options);
iv.setImageBitmap(curThumb);
【讨论】：
那么id到底是什么？
您可以在手机上的MediaStore中查询视频。 “id”只是您查询的信息之一。在developer.android.com/reference/android/provider/… 上查看有关 MediaStore 的更多信息
很惊讶每个人似乎都可以正常工作。我试过了，但 curThumb 最终为空。
如果来自 URL 的视频呢？
使用 Glide，真的很简单【参考方案3】：
使用类：
import android.provider.MediaStore.Video.Thumbnails;
我们可以从视频中获得两种预览缩略图尺寸：
Thumbnails.MICRO_KIND 为 96 x 96
Thumbnails.MINI_KIND 为 512 x 384 像素
这是一个代码示例：
String filePath = "/sdcard/DCIM/Camera/my_video.mp4"; //change the location of your file!
ImageView imageview_mini = (ImageView)findViewById(R.id.thumbnail_mini);
ImageView imageview_micro = (ImageView)findViewById(R.id.thumbnail_micro);
Bitmap bmThumbnail;
//MICRO_KIND, size: 96 x 96 thumbnail
bmThumbnail = ThumbnailUtils.createVideoThumbnail(filePath, Thumbnails.MICRO_KIND);
imageview_micro.setImageBitmap(bmThumbnail);
// MINI_KIND, size: 512 x 384 thumbnail
bmThumbnail = ThumbnailUtils.createVideoThumbnail(filePath, Thumbnails.MINI_KIND);
imageview_mini.setImageBitmap(bmThumbnail);
【讨论】：
如果我有这样的文件路径链接，这将不起作用，因为我正在尝试将其设置为图像视图并且它没有显示任何内容......这是文件路径“http： //unknown.com/v3-1aox9d1 .mp4" 显然是一个真实的域，但是那个路径不能缩略图吗？ 要使用 ThumbnailUtils 类，您必须使用方法将文件保存到磁盘：ThumbnailUtils.createVideoThumbnail( ) 谢谢，我该如何获取创建拇指的新文件路径？ 为什么 Dose 不能在 Android 4 及更高版本上运行？ 嗨 Cris，我有 3 台设备 4.1 4.2.2 和 5.0，它可以正常工作，发布一个关于您的问题和一些代码的问题，我可以为您提供帮助。【参考方案4】：我真的建议您使用 Glide 库。这是为本地视频文件生成和显示视频缩略图的最有效方式之一。
只需将此行添加到您的 gradle 文件中：
compile 'com.github.bumptech.glide:glide:3.7.0'
它会变得如此简单：
String filePath = "/storage/emulated/0/Pictures/example_video.mp4";
Glide
.with( context )
.load( Uri.fromFile( new File( filePath ) ) )
.into( imageViewGifAsBitmap );
您可以在这里找到更多信息：https://futurestud.io/blog/glide-displaying-gifs-and-videos
干杯！
【讨论】：
Glide 仅适用于本地视频，不适用于 Url 视频，没有简单的方法 部分设备不显示本地视频缩略图【参考方案5】：目前我使用以下代码：
Bitmap bMap = ThumbnailUtils.createVideoThumbnail(file.getAbsolutePath(), MediaStore.Video.Thumbnails.MICRO_KIND);
但我发现Glide 库具有以下代码更好的解决方案（它还缓存您的图像并且比以前的方法具有更好的性能）
Glide.with(context)
.load(uri)
.placeholder(R.drawable.ic_video_place_holder)
.into(imageView);
【讨论】：
【参考方案6】：试试这个对我有用
RequestOptions requestOptions = new RequestOptions();
Glide.with(getContext())
.load("video_url")
.apply(requestOptions)
.thumbnail(Glide.with(getContext()).load("video_url"))
.into("yourimageview");
【讨论】：
【参考方案7】：此解决方案适用于任何版本的 Android。它已被证明适用于 1.5 和 2.2 这不是另一个“适用于 Android 2.0+”的解决方案。我通过电子邮件留言板收集页面找到了这个，找不到原始链接。所有功劳归于原始海报。
在您的应用中，您可以通过调用来使用它：
Bitmap bm = getVideoFrame(VideoStringUri);
在它自己的函数中的某个地方（在 OnCreate 等之外），你需要：
private Bitmap getVideoFrame(String uri)
MediaMetadataRetriever retriever = new MediaMetadataRetriever();
try
retriever.setMode(MediaMetadataRetriever.MODE_CAPTURE_FRAME_ONLY);
retriever.setDataSource(uri);
return retriever.captureFrame();
catch (IllegalArgumentException ex)
ex.printStackTrace();
catch (RuntimeException ex)
ex.printStackTrace();
finally
try
retriever.release();
catch (RuntimeException ex)
return null;
在您的 src 文件夹中，您需要一个新的子目录 android/media 来存放允许您使用此功能的类（从 android 源代码本身复制）。这部分不应更改、重命名或放置在其他任何地方。 MediaMetadataRetriever.java 需要位于源文件夹中的 android.media 下才能使这一切正常工作。
/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.media;
import java.io.FileDescriptor;
import java.io.FileNotFoundException;
import java.io.IOException;
import android.content.ContentResolver;
import android.content.Context;
import android.content.res.AssetFileDescriptor;
import android.graphics.Bitmap;
import android.net.Uri;
/**
* MediaMetadataRetriever class provides a unified interface for retrieving
* frame and meta data from an input media file. @hide
*/
public class MediaMetadataRetriever
static
System.loadLibrary("media_jni");
native_init();
// The field below is accessed by native methods
private int mNativeContext;
public MediaMetadataRetriever()
native_setup();
/**
* Call this method before setDataSource() so that the mode becomes
* effective for subsequent operations. This method can be called only once
* at the beginning if the intended mode of operation for a
* MediaMetadataRetriever object remains the same for its whole lifetime,
* and thus it is unnecessary to call this method each time setDataSource()
* is called. If this is not never called (which is allowed), by default the
* intended mode of operation is to both capture frame and retrieve meta
* data (i.e., MODE_GET_METADATA_ONLY | MODE_CAPTURE_FRAME_ONLY). Often,
* this may not be what one wants, since doing this has negative performance
* impact on execution time of a call to setDataSource(), since both types
* of operations may be time consuming.
*
* @param mode
* The intended mode of operation. Can be any combination of
* MODE_GET_METADATA_ONLY and MODE_CAPTURE_FRAME_ONLY: 1.
* MODE_GET_METADATA_ONLY & MODE_CAPTURE_FRAME_ONLY: For neither
* frame capture nor meta data retrieval 2.
* MODE_GET_METADATA_ONLY: For meta data retrieval only 3.
* MODE_CAPTURE_FRAME_ONLY: For frame capture only 4.
* MODE_GET_METADATA_ONLY | MODE_CAPTURE_FRAME_ONLY: For both
* frame capture and meta data retrieval
*/
public native void setMode(int mode);
/**
* @return the current mode of operation. A negative return value indicates
* some runtime error has occurred.
*/
public native int getMode();
/**
* Sets the data source (file pathname) to use. Call this method before the
* rest of the methods in this class. This method may be time-consuming.
*
* @param path
* The path of the input media file.
* @throws IllegalArgumentException
* If the path is invalid.
*/
public native void setDataSource(String path)
throws IllegalArgumentException;
/**
* Sets the data source (FileDescriptor) to use. It is the caller's
* responsibility to close the file descriptor. It is safe to do so as soon
* as this call returns. Call this method before the rest of the methods in
* this class. This method may be time-consuming.
*
* @param fd
* the FileDescriptor for the file you want to play
* @param offset
* the offset into the file where the data to be played starts,
* in bytes. It must be non-negative
* @param length
* the length in bytes of the data to be played. It must be
* non-negative.
* @throws IllegalArgumentException
* if the arguments are invalid
*/
public native void setDataSource(FileDescriptor fd, long offset, long length)
throws IllegalArgumentException;
/**
* Sets the data source (FileDescriptor) to use. It is the caller's
* responsibility to close the file descriptor. It is safe to do so as soon
* as this call returns. Call this method before the rest of the methods in
* this class. This method may be time-consuming.
*
* @param fd
* the FileDescriptor for the file you want to play
* @throws IllegalArgumentException
* if the FileDescriptor is invalid
*/
public void setDataSource(FileDescriptor fd)
throws IllegalArgumentException
// intentionally less than LONG_MAX
setDataSource(fd, 0, 0x7ffffffffffffffL);
/**
* Sets the data source as a content Uri. Call this method before the rest
* of the methods in this class. This method may be time-consuming.
*
* @param context
* the Context to use when resolving the Uri
* @param uri
* the Content URI of the data you want to play
* @throws IllegalArgumentException
* if the Uri is invalid
* @throws SecurityException
* if the Uri cannot be used due to lack of permission.
*/
public void setDataSource(Context context, Uri uri)
throws IllegalArgumentException, SecurityException
if (uri == null)
throw new IllegalArgumentException();
String scheme = uri.getScheme();
if (scheme == null || scheme.equals("file"))
setDataSource(uri.getPath());
return;
AssetFileDescriptor fd = null;
try
ContentResolver resolver = context.getContentResolver();
try
fd = resolver.openAssetFileDescriptor(uri, "r");
catch (FileNotFoundException e)
throw new IllegalArgumentException();
if (fd == null)
throw new IllegalArgumentException();
FileDescriptor descriptor = fd.getFileDescriptor();
if (!descriptor.valid())
throw new IllegalArgumentException();
// Note: using getDeclaredLength so that our behavior is the same
// as previous versions when the content provider is returning
// a full file.
if (fd.getDeclaredLength() < 0)
setDataSource(descriptor);
else
setDataSource(descriptor, fd.getStartOffset(),
fd.getDeclaredLength());
return;
catch (SecurityException ex)
finally
try
if (fd != null)
fd.close();
catch (IOException ioEx)
setDataSource(uri.toString());
/**
* Call this method after setDataSource(). This method retrieves the meta
* data value associated with the keyCode.
*
* The keyCode currently supported is listed below as METADATA_XXX
* constants. With any other value, it returns a null pointer.
*
* @param keyCode
* One of the constants listed below at the end of the class.
* @return The meta data value associate with the given keyCode on success;
* null on failure.
*/
public native String extractMetadata(int keyCode);
/**
* Call this method after setDataSource(). This method finds a
* representative frame if successful and returns it as a bitmap. This is
* useful for generating a thumbnail for an input media source.
*
* @return A Bitmap containing a representative video frame, which can be
* null, if such a frame cannot be retrieved.
*/
public native Bitmap captureFrame();
/**
* Call this method after setDataSource(). This method finds the optional
* graphic or album art associated (embedded or external url linked) the
* related data source.
*
* @return null if no such graphic is found.
*/
public native byte[] extractAlbumArt();
/**
* Call it when one is done with the object. This method releases the memory
* allocated internally.
*/
public native void release();
private native void native_setup();
private static native void native_init();
private native final void native_finalize();
@Override
protected void finalize() throws Throwable
try
native_finalize();
finally
super.finalize();
public static final int MODE_GET_METADATA_ONLY = 0x01;
public static final int MODE_CAPTURE_FRAME_ONLY = 0x02;
/*
* Do not change these values without updating their counterparts in
* include/media/mediametadataretriever.h!
*/
public static final int METADATA_KEY_CD_TRACK_NUMBER = 0;
public static final int METADATA_KEY_ALBUM = 1;
public static final int METADATA_KEY_ARTIST = 2;
public static final int METADATA_KEY_AUTHOR = 3;
public static final int METADATA_KEY_COMPOSER = 4;
public static final int METADATA_KEY_DATE = 5;
public static final int METADATA_KEY_GENRE = 6;
public static final int METADATA_KEY_TITLE = 7;
public static final int METADATA_KEY_YEAR = 8;
public static final int METADATA_KEY_DURATION = 9;
public static final int METADATA_KEY_NUM_TRACKS = 10;
public static final int METADATA_KEY_IS_DRM_CRIPPLED = 11;
public static final int METADATA_KEY_CODEC = 12;
public static final int METADATA_KEY_RATING = 13;
public static final int METADATA_KEY_COMMENT = 14;
public static final int METADATA_KEY_COPYRIGHT = 15;
public static final int METADATA_KEY_BIT_RATE = 16;
public static final int METADATA_KEY_FRAME_RATE = 17;
public static final int METADATA_KEY_VIDEO_FORMAT = 18;
public static final int METADATA_KEY_VIDEO_HEIGHT = 19;
public static final int METADATA_KEY_VIDEO_WIDTH = 20;
public static final int METADATA_KEY_WRITER = 21;
public static final int METADATA_KEY_MIMETYPE = 22;
public static final int METADATA_KEY_DISCNUMBER = 23;
public static final int METADATA_KEY_ALBUMARTIST = 24;
// Add more here...
【讨论】：
这对我不起作用.. System.loadLibrary("media_jni"); 中的错误； 我可以确认这不起作用。我也需要这种能力。它不会工作，因为它使用常规应用程序无权使用的本机系统调用。MediaMetadataRetriever 从 API 级别 10 开始支持
MediaMetadataRetriever 是第二个代码块。它的存在是为了允许 10 之前的 API（在撰写本文时不可用）从应用程序而不是系统访问代码。本地系统调用是可能的，但您需要对系统有一个粗略的了解才能使用它们。听起来很多问题都在不正确地实现所提供的源代码。
@LoungeKatt 是否可以让它多次捕获同一视频的多个图像？【参考方案8】：
Android 1.5 和 1.6 不提供此缩略图，但 2.0 提供，如 the official release notes 所示：
媒体
MediaScanner 现在会在将所有图像插入 MediaStore 时为其生成缩略图。 新的 Thumbnail API 用于按需检索图像和视频缩略图。
【讨论】：
【参考方案9】：我回答这个问题较晚，但希望它能帮助其他面临同样问题的候选人。
我使用了两种方法来加载视频列表的缩略图，第一种是
Bitmap bmThumbnail;
bmThumbnail = ThumbnailUtils.createVideoThumbnail(FILE_PATH
+ videoList.get(position),
MediaStore.Video.Thumbnails.MINI_KIND);
if (bmThumbnail != null)
Log.d("VideoAdapter","video thumbnail found");
holder.imgVideo.setImageBitmap(bmThumbnail);
else
Log.d("VideoAdapter","video thumbnail not found");
它看起来不错，但这个解决方案存在问题，因为当我滚动视频列表时，由于处理量大，它会冻结一段时间。
所以在此之后我找到了另一个使用 Glide Library 完美运行的解决方案。
Glide
.with( mContext )
.load( Uri.fromFile( new File( FILE_PATH+videoList.get(position) ) ) )
.into( holder.imgVideo );
我推荐后一种解决方案来显示带有视频列表的缩略图。 谢谢
【讨论】：
嗨@AllanRibas 很高兴听到这个解决方案对您有用。【参考方案10】：这是实时视频缩略图的代码。
public class LoadVideoThumbnail extends AsyncTask<Object, Object, Bitmap>
@Override
protected Bitmap doInBackground(Object... params) try
String mMediaPath = "http://commonsware.com/misc/test2.3gp";
Log.e("TEST Chirag","<< thumbnail doInBackground"+ mMediaPath);
FileOutputStream out;
File land=new File(Environment.getExternalStorageDirectory().getAbsoluteFile()
+"/portland.jpg");
Bitmap bitmap = ThumbnailUtils.createVideoThumbnail(mMediaPath, MediaStore.Video.Thumbnails.MICRO_KIND);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, stream);
byte[] byteArray = stream.toByteArray();
out=new FileOutputStream(land.getPath());
out.write(byteArray);
out.close();
return bitmap;
catch (FileNotFoundException e)
// TODO Auto-generated catch block
e.printStackTrace();
catch (IOException e)
// TODO Auto-generated catch block
e.printStackTrace();
return null;
@Override
protected void onPostExecute(Bitmap result)
// TODO Auto-generated method stub
super.onPostExecute(result);
if(result != null)
((ImageView)findViewById(R.id.imageView1)).setImageBitmap(result);
Log.e("TEST Chirag","====> End");
【讨论】：
我在Bitmap bitmap = ThumbnailUtils.createVideoThumbnail(mMediaPath, MediaStore.Video.Thumbnails.MICRO_KIND); 得到 null 请注意，所有参数都已设置
位图位图的空值 = ThumbnailUtils.createVideoThumbnail(mMediaPath, MediaStore.Video.Thumbnails.MICRO_KIND);以上是关于Android：是不是可以显示视频缩略图？的主要内容，如果未能解决你的问题，请参考以下文章