嗨，我正在处理视频，我想从库中获取视频文件列表以显示并在我的应用程序中播放视频。谁能帮我。
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10814 次
7 回答
11
allVideos = [[NSMutableArray alloc] init];
ALAssetsLibrary *assetLibrary = [[ALAssetsLibrary alloc] init];
[assetLibrary enumerateGroupsWithTypes:ALAssetsGroupAll usingBlock:^(ALAssetsGroup *group, BOOL *stop)
{
if (group)
{
[group setAssetsFilter:[ALAssetsFilter allVideos]];
[group enumerateAssetsUsingBlock:^(ALAsset *asset, NSUInteger index, BOOL *stop)
{
if (asset)
{
dic = [[NSMutableDictionary alloc] init];
ALAssetRepresentation *defaultRepresentation = [asset defaultRepresentation];
NSString *uti = [defaultRepresentation UTI];
NSURL *videoURL = [[asset valueForProperty:ALAssetPropertyURLs] valueForKey:uti];
NSString *title = [NSString stringWithFormat:@"video %d", arc4random()%100];
UIImage *image = [self imageFromVideoURL:videoURL];
[dic setValue:image forKey:@"image"];
[dic setValue:title forKey:@"name"];
[dic setValue:videoURL forKey:@"url"];
[allVideos addObject:dic];
}
}];
else
{
}
}
failureBlock:^(NSError *error)
{
NSLog(@"error enumerating AssetLibrary groups %@\n", error);
}];
于 2013-07-15T12:45:12.213 回答
3
它将打开照片库并仅显示电影类型的内容。
#import <MobileCoreServices/MobileCoreServices.h>
UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
imagePicker.delegate = self;
imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
imagePicker.mediaTypes = [[NSArray alloc] initWithObjects:(NSString *)kUTTypeMovie, nil];
[self presentModalViewController:imagePicker animated:YES];
于 2013-07-11T06:00:24.283 回答
3
获取所有视频和缩略图的列表
感谢@Nikhil，他在这里分享了信息，它帮助了我，但仍然需要几个小时才能使代码可执行，因为他在回答中遗漏了一些东西
所以我想分享我的完整工作代码
1.只需添加框架AssetsLibrary、AVFoundation和MediaPlayer。
2. AssetBrowserItem.h和AssetBrowserItem.m 这里
3.使用下面的代码从ios设备库中获取所有视频的列表
4.运行应用程序并查看日志以获取视频详细信息
#import "HomeViewController.h"
#import <AssetsLibrary/AssetsLibrary.h>
#import <MediaPlayer/MediaPlayer.h>
#import <AVFoundation/AVFoundation.h>
#import "AssetBrowserItem.h"
@interface HomeViewController ()
@property (nonatomic, strong) ALAssetsLibrary *assetsLibrary;
@property (nonatomic, strong) NSURL *videoURL;
@property (nonatomic, strong) MPMoviePlayerController *mpVideoPlayer;
@property (nonatomic, strong) NSMutableArray *videoURLArray;
@property (nonatomic, strong) NSMutableArray *assetItems;
@property (nonatomic, strong) NSMutableDictionary *dic;
@end
@implementation HomeViewController
@synthesize assetsLibrary, assetItems,dic;
@synthesize videoURL,videoURLArray, mpVideoPlayer;
- (void)viewDidLoad
{
[super viewDidLoad];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
}
#pragma mark - Show Video List Methods
- (IBAction)showVideoList:(id)sender
{
[self buildAssetsLibrary];
}
- (void)buildAssetsLibrary
{
assetsLibrary = [[ALAssetsLibrary alloc] init];
ALAssetsLibrary *notificationSender = nil;
videoURLArray = [[NSMutableArray alloc] init];
NSString *minimumSystemVersion = @"4.1";
NSString *systemVersion = [[UIDevice currentDevice] systemVersion];
if ([systemVersion compare:minimumSystemVersion options:NSNumericSearch] != NSOrderedAscending)
notificationSender = assetsLibrary;
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(assetsLibraryDidChange:) name:ALAssetsLibraryChangedNotification object:notificationSender];
[self updateAssetsLibrary];
}
- (void)assetsLibraryDidChange:(NSNotification*)changeNotification
{
[self updateAssetsLibrary];
}
- (void)updateAssetsLibrary
{
assetItems = [NSMutableArray arrayWithCapacity:0];
ALAssetsLibrary *assetLibrary = assetsLibrary;
[assetLibrary enumerateGroupsWithTypes:ALAssetsGroupAll usingBlock:^(ALAssetsGroup *group, BOOL *stop)
{
if (group)
{
[group setAssetsFilter:[ALAssetsFilter allVideos]];
[group enumerateAssetsUsingBlock:^(ALAsset *asset, NSUInteger index, BOOL *stop)
{
if (asset)
{
dic = [[NSMutableDictionary alloc] init];
ALAssetRepresentation *defaultRepresentation = [asset defaultRepresentation];
NSString *uti = [defaultRepresentation UTI];
videoURL = [[asset valueForProperty:ALAssetPropertyURLs] valueForKey:uti];
mpVideoPlayer = [[MPMoviePlayerController alloc] initWithContentURL:videoURL];
NSString *title = [NSString stringWithFormat:@"%@ %lu", NSLocalizedString(@"Video", nil), [assetItems count]+1];
[self performSelector:@selector(imageFromVideoURL)];
[dic setValue:title forKey:@"VideoTitle"];//kName
[dic setValue:videoURL forKey:@"VideoUrl"];//kURL
AssetBrowserItem *item = [[AssetBrowserItem alloc] initWithURL:videoURL title:title];
[assetItems addObject:item];
[videoURLArray addObject:dic];
NSLog(@"Video has info:%@",videoURLArray);
}
NSLog(@"Values of dictonary==>%@", dic);
//NSLog(@"assetItems:%@",assetItems);
NSLog(@"Videos Are:%@",videoURLArray);
} ];
}
// group == nil signals we are done iterating.
else
{
dispatch_async(dispatch_get_main_queue(), ^{
//[self updateBrowserItemsAndSignalDelegate:assetItems];
// loadImgView.hidden = NO;
// [spinner stopAnimating];
// [loadImgView removeFromSuperview];
//selectVideoBtn .userInteractionEnabled = YES;
});
}
}
failureBlock:^(NSError *error)
{
NSLog(@"error enumerating AssetLibrary groups %@\n", error);
}];
}
- (UIImage *)imageFromVideoURL
{
UIImage *image = nil;
AVAsset *asset = [[AVURLAsset alloc] initWithURL:videoURL options:nil];;
AVAssetImageGenerator *imageGenerator = [[AVAssetImageGenerator alloc] initWithAsset:asset];
imageGenerator.appliesPreferredTrackTransform = YES;
// calc midpoint time of video
Float64 durationSeconds = CMTimeGetSeconds([asset duration]);
CMTime midpoint = CMTimeMakeWithSeconds(durationSeconds/2.0, 600);
// get the image from
NSError *error = nil;
CMTime actualTime;
CGImageRef halfWayImage = [imageGenerator copyCGImageAtTime:midpoint actualTime:&actualTime error:&error];
if (halfWayImage != NULL)
{
// cgimage to uiimage
image = [[UIImage alloc] initWithCGImage:halfWayImage];
[dic setValue:image forKey:@"ImageThumbnail"];//kImage
NSLog(@"Values of dictonary==>%@", dic);
NSLog(@"Videos Are:%@",videoURLArray);
CGImageRelease(halfWayImage);
}
return image;
}
@end
于 2015-02-05T12:06:30.070 回答
3
在swift 4.0中，这就是我使用照片框架中的 fetchAsset() 方法从照片库中获取所有视频的方式。
您还可以使用谓词从特定文件夹中获取视频。
func fetchAllVideos()
{
//let albumName = "blah"
let fetchOptions = PHFetchOptions()
// fetchOptions.predicate = NSPredicate(format: "title = %@", albumName)
//uncomment this if you want video from custom folder
fetchOptions.predicate = NSPredicate(format: "mediaType = %d ", PHAssetMediaType.video.rawValue )
let allVideo = PHAsset.fetchAssets(with: .video, options: fetchOptions)
allVideo.enumerateObjects { (asset, index, bool) in
// videoAssets.append(asset)
let imageManager = PHCachingImageManager()
imageManager.requestAVAsset(forVideo: asset, options: nil, resultHandler: { (asset, audioMix, info) in
if asset != nil {
let avasset = asset as! AVURLAsset
let urlVideo = avasset.url
print(urlVideo)
}
})
}
}
于 2019-11-22T14:13:19.530 回答
1
查看博客文章以使用照片框架获取所有视频资产 http://iavinashkashyap.blogspot.in/2016/11/get-list-of-all-videos.html
代码：
-（无效）getAllVideoAssets{
NSMutableArray *assets = [[NSMutableArray alloc] init];
//Fetch all video assets from Photos
PHFetchResult *assetResults = [PHAsset fetchAssetsWithMediaType:PHAssetMediaTypeVideo options:nil];
//get all assets
for (PHAsset *asset in assetResults){
NSLog(@"asset type = %zd", asset.mediaType);
[assets addObject:asset];
}
self.allVideoslistArray = [[NSMutableArray alloc] init];
//create an instance of PHImageManager
PHImageManager *manager = [PHImageManager defaultManager];
for(PHAsset *asset in assets){
//block of code for represent video assets
[manager requestAVAssetForVideo:asset options:nil resultHandler:^(AVAsset * _Nullable asset, AVAudioMix * _Nullable audioMix, NSDictionary * _Nullable info) {
if ([asset isKindOfClass:[AVURLAsset class]]) {
NSURL *url = (NSURL *)[[(AVURLAsset *)asset URL] fileReferenceURL];
UIImage *thumbnail = [self createThunbnailImage:url];
[self.allVideoslistArray addObject:@{@"VideoUrl":url,@"ThumbnailImage":thumbnail, @"VideoAsset":asset}];
}
}];
}//end for loop
}
于 2016-11-28T09:06:26.800 回答
0
请参考以下链接。可能对你有帮助
http://www.raywenderlich.com/13418/how-to-play-record-edit-videos-in-ios
祝你好运！！！
于 2013-07-11T06:02:42.830 回答
0
使用此方法从库中选择视频。
//Call this method.
[self startMediaBrowserFromViewController: self usingDelegate: self];
- (BOOL) startMediaBrowserFromViewController: (UIViewController*) controller usingDelegate: (id <UIImagePickerControllerDelegate, UINavigationControllerDelegate>) delegate{
if (([UIImagePickerController isSourceTypeAvailable: UIImagePickerControllerSourceTypeSavedPhotosAlbum] == NO) || (delegate == nil) || (controller == nil))
return NO;
UIImagePickerController *mediaUI = [[UIImagePickerController alloc] init];
mediaUI.sourceType = UIImagePickerControllerSourceTypeSavedPhotosAlbum;
mediaUI.mediaTypes = [[[NSArray alloc] initWithObjects: (NSString *) kUTTypeMovie, nil] autorelease];
mediaUI.allowsEditing = YES;
mediaUI.delegate = self;
mediaUI.videoMaximumDuration = 60.0;
//mediaUI.videoQuality = UIImagePickerControllerQualityTypeLow;
[controller presentModalViewController: mediaUI animated: YES];
return YES;
}
于 2013-07-11T06:13:31.640 回答