问题描述
我发送一个意图发动摄像机
I send an intent to launch the video camera
PackageManager pm = getPackageManager();
if(pm.hasSystemFeature(PackageManager.FEATURE_CAMERA)){
Intent video = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);
File tempDir= new File(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_PICTURES), "BCA");
if(!tempDir.exists())
{
if(!tempDir.mkdir()){
Toast.makeText(this, "Please check SD card! Image shot is impossible!", Toast.LENGTH_SHORT).show();
}
}
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss",Locale.US).format(new Date());
File mediaFile = new File(tempDir.getPath() + File.separator +
"VIDEO_"+ timeStamp + ".mp4");
Uri videoUri = Uri.fromFile(mediaFile);
video.putExtra(MediaStore.EXTRA_OUTPUT, videoUri);
video.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 1);
startActivityForResult(video, VIDEO_REQUEST);
}else{
Toast.makeText(this, "This device does not have a rear facing camera",Toast.LENGTH_SHORT).show();
}
我把一个视频,它得到正确地存储,当的onActivityResult
解雇我使用的意图,以获得 URI
其中,其存储创建位图
i take a video and it gets store correctly, When the onActivityResult
get fired I use the intent to get the uri
where its stored to create the bitmap
这是URI 的示例文件:///storage/emulated/0/Pictures/BCA/VIDEO_20131227_145043.mp4
Bitmap bitmap = ThumbnailUtils.createVideoThumbnail(intent.getDataString(), MediaStore.Video.Thumbnails.MICRO_KIND);
但位为空每次。如此以来,文档说可能返回null如果视频损坏或不支持的格式
我检查该目录中的视频,它起着罚款加上其在 .MP4
这是支持这样的文件我究竟做错了什么?
but the bitmap is null everytime. So since the docs say May return null if the video is corrupt or the format is not supported
I check the video in the directory and it plays fine plus its a .mp4
file which is supported so what am I doing wrong here?
推荐答案
我记得参数文件路径
从 createVideoThumbnail 应该是一个经典的文件路径,而不是 URI
。
As I remember, argument filePath
from createVideoThumbnail should be a classic filepath, not URI
.
...
Uri videoUri = intent.getData();
final String realFilePath = getRealPathFromUri();
Bitmap bitmap = ThumbnailUtils.createVideoThumbnail(realFilePath, MediaStore.Video.Thumbnails.MICRO_KIND);
...
public String getRealPathFromURI(final Uri contentURI) {
Cursor cursor = getContentResolver().query(contentURI, null, null, null, null);
if (cursor == null) { // Source is Dropbox or other similar local file path
return contentURI.getPath();
} else {
cursor.moveToFirst();
int idx = cursor.getColumnIndex(MediaStore.MediaColumns.DATA);
if ( idx == -1 ) {
return contentURI.getPath();
}
String rvalue = cursor.getString(idx);
cursor.close();
return rvalue;
}
}
编辑:
,我创造了另一个实现:
Based on the source code of createVideoThumbnail
, I created another implementation:
public static Bitmap createVideoThumbnail(Context context, Uri uri, int kind) {
Bitmap bitmap = null;
MediaMetadataRetriever retriever = new MediaMetadataRetriever();
try {
retriever.setMode(MediaMetadataRetriever.MODE_CAPTURE_FRAME_ONLY);
retriever.setDataSource(context, uri);
bitmap = retriever.captureFrame();
} catch (IllegalArgumentException ex) {
// Assume this is a corrupt video file
} catch (RuntimeException ex) {
// Assume this is a corrupt video file.
} finally {
try {
retriever.release();
} catch (RuntimeException ex) {
// Ignore failures while cleaning up.
}
}
if (kind == Images.Thumbnails.MICRO_KIND && bitmap != null) {
bitmap = ThumbnailUtils.extractThumbnail(bitmap,
ThumbnailUtils.TARGET_SIZE_MICRO_THUMBNAIL,
ThumbnailUtils.TARGET_SIZE_MICRO_THUMBNAIL,
ThumbnailUtils.OPTIONS_RECYCLE_INPUT);
}
return bitmap;
}
这篇关于从视频文件创建缩略图返回null位图的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!