最近在重构自己写的代码，项目中需要将相册中的视频上传到云服务器。做个总结。
使用UIImagePickerController获取相册的视频，研究发现，获取后的视频是经过压缩的，经测试如果一个3M的视频经过压缩后会变成1.3M.如果你们服务器需要的正是经过压缩的，那么恭喜你，不用走那么多弯路了。我这边恰好需要的是不经过压缩的视频，然后网上找了很多方法，发现要获取相册中的视频是必须经过压缩的（如果你有获取相册原生视频的方法请在下方留言告诉我，万分感谢！），既然不让获取原生的，那么只能退而求其次, ipc.sourceType = UIImagePickerControllerSourceTypePhotoLibraryshi;（这个方法呢有个问题，就是如果视频的分辨率小于手机的分辨率，视频会变大，一般3M会变成10.3M,有多大自己体会~）设置视频的导出质量为高质量。
UIImagePickerController *ipc=[[UIImagePickerController alloc] init];
ipc=[[UIImagePickerController alloc] init];
ipc.delegate=self;
ipc.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
ipc.videoQuality = UIImagePickerControllerQualityTypeMedium;
ipc.mediaTypes = [NSArray arrayWithObjects:@"public.movie", nil];
一般呢，我们会在didFinishPickingMediaWithInfo代理方法中获取视频路径。
这个时候我们得出的是临时路径，不能是指作为视频路径直接上传，我再模拟器下截取了这个临时路径，如图：
temp.jpeg
我们需要把原视频导出到自己的APP内，而后根据这个路径进行上传即可。
导出的方法也有两种：
一是根据路径直接拷贝，二是进行视频导出，第二中方式可以对视频进行进一步压缩。可以根据自己的项目需求选择。
代码如下(ViewController页面全部代码)：
#import "ViewController.h"
#import <AVFoundation/AVFoundation.h>
@interface ViewController ()<UIImagePickerControllerDelegate,UINavigationControllerDelegate,UITextViewDelegate>
@property (weak, nonatomic) IBOutlet UIImageView *videoImageView;
@property (weak, nonatomic) IBOutlet UILabel *videoMessageLabel;
@property (nonatomic,assign)BOOL isImagePicker;
@property (nonatomic,strong)NSString *filePath;
@property (nonatomic,strong)NSString *imagePath;
@property (nonatomic,strong)NSString *pingUploadUrlString;
@property (nonatomic,assign)NSInteger timeSecond;
@end
@implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
NSLog(@"%@",NSHomeDirectory());
}
- (IBAction)getVideo:(UIButton *)sender
{
if ([UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypePhotoLibrary])
{
UIImagePickerController *ipc=[[UIImagePickerController alloc] init];
ipc=[[UIImagePickerController alloc] init];
ipc.delegate=self;
ipc.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
ipc.videoQuality = UIImagePickerControllerQualityTypeMedium;
ipc.mediaTypes = [NSArray arrayWithObjects:@"public.movie", nil];
[self presentViewController:ipc animated:YES completion:nil];
_isImagePicker = YES;
}
}
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
NSString *mediaType = [info objectForKey:UIImagePickerControllerMediaType];
if ([mediaType isEqualToString:@"public.movie"])
{
NSURL *videoUrl = [info objectForKey:UIImagePickerControllerMediaURL];
AVURLAsset *asset = [AVURLAsset assetWithURL:videoUrl];
NSString *videoPath = info[UIImagePickerControllerMediaURL];
NSLog(@"相册视频路径是：%@",videoPath);
//第一中方法，通过路径直接copy
// //删除原来的 防止重复选
// [[NSFileManager defaultManager] removeItemAtPath:_filePath error:nil];
// [[NSFileManager defaultManager] removeItemAtPath:_imagePath error:nil];
// NSDateFormatter *formater = [[NSDateFormatter alloc] init];
// [formater setDateFormat:@"yy-MM-dd-HH:mm:ss"];
//
// _filePath = [NSHomeDirectory() stringByAppendingFormat:@"/Documents/%@", [[formater stringFromDate:[NSDate date]] stringByAppendingString:@".mp4"]];
//
//
// NSString *videoPath = info[UIImagePickerControllerMediaURL];
//
// NSFileManager *fileManager = [NSFileManager defaultManager];
//
// NSError *error;
// [fileManager copyItemAtPath:videoPath toPath:_filePath error:&error];
// if (error)
// {
//
// NSLog(@"文件保存到缓存失败");
// }
//
// [self getSomeMessageWithFilePath:_filePath];
//第二种方法，进行视频导出
[self startExportVideoWithVideoAsset:asset completion:^(NSString *outputPath) {
[self getSomeMessageWithFilePath:_filePath];
}];;
}
_isImagePicker = NO;
[picker dismissViewControllerAnimated:YES completion:nil];
}
//获取视频第一帧
- (void)getSomeMessageWithFilePath:(NSString *)filePath
{
NSURL *fileUrl = [NSURL fileURLWithPath:filePath];
AVURLAsset *asset = [AVURLAsset assetWithURL:fileUrl];
NSString *duration = [NSString stringWithFormat:@"%0.0f", ceil(CMTimeGetSeconds(asset.duration))];
_videoImageView.image = [self getImageWithAsset:asset];
// _image = _imageView.image;
_timeSecond = duration.integerValue;
_videoMessageLabel.text = [NSString stringWithFormat:@"时长是:%ld",(long)_timeSecond];
NSLog(@"时长是：%@",duration);
}
- (UIImage *)getImageWithAsset:(AVAsset *)asset
{
AVURLAsset *assetUrl = (AVURLAsset *)asset;
NSParameterAssert(assetUrl);
AVAssetImageGenerator *assetImageGenerator =[[AVAssetImageGenerator alloc] initWithAsset:assetUrl];
assetImageGenerator.appliesPreferredTrackTransform = YES;
assetImageGenerator.apertureMode = AVAssetImageGeneratorApertureModeEncodedPixels;
CGImageRef thumbnailImageRef = NULL;
CFTimeInterval thumbnailImageTime = 0;
NSError *thumbnailImageGenerationError = nil;
thumbnailImageRef = [assetImageGenerator copyCGImageAtTime:CMTimeMake(thumbnailImageTime, 60)actualTime:NULL error:&thumbnailImageGenerationError];
if(!thumbnailImageRef)
NSLog(@"thumbnailImageGenerationError %@",thumbnailImageGenerationError);
UIImage *thumbnailImage = thumbnailImageRef ? [[UIImage alloc]initWithCGImage: thumbnailImageRef] : nil;
return thumbnailImage;
}
- (void)startExportVideoWithVideoAsset:(AVURLAsset *)videoAsset completion:(void (^)(NSString *outputPath))completion
{
// Find compatible presets by video asset.
NSArray *presets = [AVAssetExportSession exportPresetsCompatibleWithAsset:videoAsset];
NSString *pre = nil;
if ([presets containsObject:AVAssetExportPreset3840x2160])
{
pre = AVAssetExportPreset3840x2160;
}
else if([presets containsObject:AVAssetExportPreset1920x1080])
{
pre = AVAssetExportPreset1920x1080;
}
else if([presets containsObject:AVAssetExportPreset1280x720])
{
pre = AVAssetExportPreset1280x720;
}
else if([presets containsObject:AVAssetExportPreset960x540])
{
pre = AVAssetExportPreset1280x720;
}
else
{
pre = AVAssetExportPreset640x480;
}
// Begin to compress video
// Now we just compress to low resolution if it supports
// If you need to upload to the server, but server does't support to upload by streaming,
// You can compress the resolution to lower. Or you can support more higher resolution.
if ([presets containsObject:AVAssetExportPreset640x480]) {
// AVAssetExportSession *session = [[AVAssetExportSession alloc]initWithAsset:videoAsset presetName:AVAssetExportPreset640x480];
AVAssetExportSession *session = [[AVAssetExportSession alloc]initWithAsset:videoAsset presetName:AVAssetExportPreset640x480];
NSDateFormatter *formater = [[NSDateFormatter alloc] init];
[formater setDateFormat:@"yy-MM-dd-HH:mm:ss"];
NSString *outputPath = [NSHomeDirectory() stringByAppendingFormat:@"/Documents/%@", [[formater stringFromDate:[NSDate date]] stringByAppendingString:@".mov"]];
NSLog(@"video outputPath = %@",outputPath);
//删除原来的 防止重复选
_timeSecond = 0;
[[NSFileManager defaultManager] removeItemAtPath:_filePath error:nil];
[[NSFileManager defaultManager] removeItemAtPath:_imagePath error:nil];
_filePath = outputPath;
session.outputURL = [NSURL fileURLWithPath:outputPath];
// Optimize for network use.
session.shouldOptimizeForNetworkUse = true;
NSArray *supportedTypeArray = session.supportedFileTypes;
if ([supportedTypeArray containsObject:AVFileTypeMPEG4]) {
session.outputFileType = AVFileTypeMPEG4;
} else if (supportedTypeArray.count == 0) {
NSLog(@"No supported file types 视频类型暂不支持导出");
return;
} else {
session.outputFileType = [supportedTypeArray objectAtIndex:0];
}
if (![[NSFileManager defaultManager] fileExistsAtPath:[NSHomeDirectory() stringByAppendingFormat:@"/Documents"]]) {
[[NSFileManager defaultManager] createDirectoryAtPath:[NSHomeDirectory() stringByAppendingFormat:@"/Documents"] withIntermediateDirectories:YES attributes:nil error:nil];
}
if ([[NSFileManager defaultManager] fileExistsAtPath:outputPath]) {
[[NSFileManager defaultManager] removeItemAtPath:outputPath error:nil];
}
// Begin to export video to the output path asynchronously.
[session exportAsynchronouslyWithCompletionHandler:^(void) {
switch (session.status) {
case AVAssetExportSessionStatusUnknown:
NSLog(@"AVAssetExportSessionStatusUnknown"); break;
case AVAssetExportSessionStatusWaiting:
NSLog(@"AVAssetExportSessionStatusWaiting"); break;
case AVAssetExportSessionStatusExporting:
NSLog(@"AVAssetExportSessionStatusExporting"); break;
case AVAssetExportSessionStatusCompleted: {
NSLog(@"AVAssetExportSessionStatusCompleted");
dispatch_async(dispatch_get_main_queue(), ^{
if (completion) {
completion(outputPath);
}
// _videoArray = [VRVideoTool getAllFileNameFormDoucuments];
// [_tableView reloadData];
});
} break;
case AVAssetExportSessionStatusFailed:
NSLog(@"AVAssetExportSessionStatusFailed"); break;
default: break;
}
}];
}
}
@end
获取视频第一帧图片的原理是通过视频路径获取视频的AVURLAsset，通过对AVURLAsset进行处理可以获得视频的一些信息，例如时长，第一帧图片等。上面代码里面有，不再赘述。
如果你有更好的获取相册视频的方法，请在下方留言告知~~。
DEMO地址
