最新做的一个功能涉及到了视频的录制、压缩及上传。根据网上诸多大神的经验，终于算是调通了，但也发现了一些问题，所以把我的经验分享一下。
首先，肯定是调用一下系统的相机或相册
代码很基本：
//选择本地视频
- (void)choosevideo
{
UIImagePickerController *ipc = [[UIImagePickerController alloc] init];
ipc.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;//sourcetype有三种分别是camera，photoLibrary和photoAlbum
NSArray *availableMedia = [UIImagePickerController availableMediaTypesForSourceType:UIImagePickerControllerSourceTypeCamera];//Camera所支持的Media格式都有哪些,共有两个分别是@"public.image",@"public.movie"
ipc.mediaTypes = [NSArray arrayWithObject:availableMedia[1]];//设置媒体类型为public.movie
[self presentViewController:ipc animated:YES completion:nil];
ipc.delegate = self;//设置委托
}
//录制视频
- (void)startvideo
{
UIImagePickerController *ipc = [[UIImagePickerController alloc] init];
ipc.sourceType = UIImagePickerControllerSourceTypeCamera;//sourcetype有三种分别是camera，photoLibrary和photoAlbum
NSArray *availableMedia = [UIImagePickerController availableMediaTypesForSourceType:UIImagePickerControllerSourceTypeCamera];//Camera所支持的Media格式都有哪些,共有两个分别是@"public.image",@"public.movie"
ipc.mediaTypes = [NSArray arrayWithObject:availableMedia[1]];//设置媒体类型为public.movie
[self presentViewController:ipc animated:YES completion:nil];
ipc.videoMaximumDuration = 30.0f;//30秒
ipc.delegate = self;//设置委托
}
iOS录制的视频格式是mov的，在Android和Pc上都不太好支持，所以要转换为MP4格式的，而且压缩一下，毕竟我们上传的都是小视频，不用特别清楚
为了反馈的清楚，先放两个小代码来获取视频的时长和大小，也是在网上找的，稍微改了一下。
- (CGFloat) getFileSize:(NSString *)path
{
NSLog(@"%@",path);
NSFileManager *fileManager = [NSFileManager defaultManager];
float filesize = -1.0;
if ([fileManager fileExistsAtPath:path]) {
NSDictionary *fileDic = [fileManager attributesOfItemAtPath:path error:nil];//获取文件的属性
unsigned long long size = [[fileDic objectForKey:NSFileSize] longLongValue];
filesize = 1.0*size/1024;
}else{
NSLog(@"找不到文件");
}
return filesize;
}//此方法可以获取文件的大小，返回的是单位是KB。
- (CGFloat) getVideoLength:(NSURL *)URL
{
AVURLAsset *avUrl = [AVURLAsset assetWithURL:URL];
CMTime time = [avUrl duration];
int second = ceil(time.value/time.timescale);
return second;
}//此方法可以获取视频文件的时长。
接收并压缩
//完成视频录制，并压缩后显示大小、时长
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
{
NSURL *sourceURL = [info objectForKey:UIImagePickerControllerMediaURL];
NSLog(@"%@",[NSString stringWithFormat:@"%f s", [self getVideoLength:sourceURL]]);
NSLog(@"%@", [NSString stringWithFormat:@"%.2f kb", [self getFileSize:[sourceURL path]]]);
NSURL *newVideoUrl ; //一般.mp4
NSDateFormatter *formater = [[NSDateFormatter alloc] init];//用时间给文件全名，以免重复，在测试的时候其实可以判断文件是否存在若存在，则删除，重新生成文件即可
[formater setDateFormat:@"yyyy-MM-dd-HH:mm:ss"];
newVideoUrl = [NSURL fileURLWithPath:[NSHomeDirectory() stringByAppendingFormat:@"/Documents/output-%@.mp4", [formater stringFromDate:[NSDate date]]]] ;//这个是保存在app自己的沙盒路径里，后面可以选择是否在上传后删除掉。我建议删除掉，免得占空间。
[picker dismissViewControllerAnimated:YES completion:nil];
[self convertVideoQuailtyWithInputURL:sourceURL outputURL:newVideoUrl completeHandler:nil];
}
- (void) convertVideoQuailtyWithInputURL:(NSURL*)inputURL
outputURL:(NSURL*)outputURL
completeHandler:(void (^)(AVAssetExportSession*))handler
{
AVURLAsset *avAsset = [AVURLAsset URLAssetWithURL:inputURL options:nil];
AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:avAsset presetName:AVAssetExportPresetMediumQuality];
// NSLog(resultPath);
exportSession.outputURL = outputURL;
exportSession.outputFileType = AVFileTypeMPEG4;
exportSession.shouldOptimizeForNetworkUse= YES;
[exportSession exportAsynchronouslyWithCompletionHandler:^(void)
{
switch (exportSession.status) {
case AVAssetExportSessionStatusCancelled:
NSLog(@"AVAssetExportSessionStatusCancelled");
break;
case AVAssetExportSessionStatusUnknown:
NSLog(@"AVAssetExportSessionStatusUnknown");
break;
case AVAssetExportSessionStatusWaiting:
NSLog(@"AVAssetExportSessionStatusWaiting");
break;
case AVAssetExportSessionStatusExporting:
NSLog(@"AVAssetExportSessionStatusExporting");
break;
case AVAssetExportSessionStatusCompleted:
NSLog(@"AVAssetExportSessionStatusCompleted");
NSLog(@"%@",[NSString stringWithFormat:@"%f s", [self getVideoLength:outputURL]]);
NSLog(@"%@", [NSString stringWithFormat:@"%.2f kb", [self getFileSize:[outputURL path]]]);
//UISaveVideoAtPathToSavedPhotosAlbum([outputURL path], self, nil, NULL);//这个是保存到手机相册
[self alertUploadVideo:outputURL];
break;
case AVAssetExportSessionStatusFailed:
NSLog(@"AVAssetExportSessionStatusFailed");
break;
}
}];
}
