如何录制视频
我们使用UIImagePickerController类设置媒体类型为视频
凡是涉及到与硬件交互,保险的做法是先判断是否可用.
我们使用UIImagePickerController的类方法来判断相机是否可用:判断可用的方法如下:
-(BOOL)isCramaAvialable{
//相机是否可用
return [UIImagePickerController isSourceTypeAvailable:UIImagePickerControllerSourceTypeCamera];
// //后置相机是否可用
// [UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceRear];
// //前置相机是否可用
// [UIImagePickerController isCameraDeviceAvailable:UIImagePickerControllerCameraDeviceFront];
// //后置闪光灯是否可用
// [UIImagePickerController isFlashAvailableForCameraDevice:UIImagePickerControllerCameraDeviceRear];
// //前置闪光灯是否可用
// [UIImagePickerController isFlashAvailableForCameraDevice:UIImagePickerControllerCameraDeviceFront];
}
判断指定资源类型下的媒体类型是否可用
这里的资源类型是指 相机还是图库等
媒体类型是指 是图片还是视频 视频选用movie 而不是video 请注意
-(BOOL)isAvalableMediaType:(CFStringRef)mediaType sourcType:(UIImagePickerControllerSourceType)soureType{
NSArray *array = [UIImagePickerController availableMediaTypesForSourceType:soureType];
NSLog(@"%@",array);
return [array containsObject:(__bridge NSString *)mediaType];
}
第一步我们配置的代码这一这么写:
//1.判断相机是否可用 视频是否可用
if (![self isCramaAvialable]) {
UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"相机不可用" message:nil preferredStyle:UIAlertControllerStyleAlert];
[alert addAction:[UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleDefault handler:nil]];
[self presentViewController:alert animated:YES completion:nil];
return;
}
配置UIImagePickerController 并present出来
我们需要在这里配置PickerController的资源类型/媒体类型等,闪光灯,录制时间,视频质量,都可以在这里设置.
-(void)configPicker{
self.pickerContr = [[UIImagePickerController alloc]init];
//设置资源类型
[self.pickerContr setSourceType:UIImagePickerControllerSourceTypeCamera];
if ([self isAvalableMediaType:kUTTypeMovie sourcType:UIImagePickerControllerSourceTypeCamera]) {
//配置媒体类型
[self.pickerContr setMediaTypes:@[(__bridge NSString *)kUTTypeMovie]];
//配置视频质量
[self.pickerContr setVideoQuality:UIImagePickerControllerQualityTypeHigh];
//设置最大录制时间
[self.pickerContr setVideoMaximumDuration:10];
//设置代理
self.pickerContr.delegate = self;
[self presentViewController:self.pickerContr animated:YES completion:nil];
}else{
UIAlertController *alert = [UIAlertController alertControllerWithTitle:@"视频不可用" message:nil preferredStyle:UIAlertControllerStyleAlert];
[alert addAction:[UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleDefault handler:nil]];
[self presentViewController:alert animated:YES completion:nil];
}
}
保存视频
这一步已经可以进行视频录制了,但是还没对拿到的视频数据尽心处理.刚才我们设置代理,视频的处理需要在代理的回调方法里进行;除了取消的代理方法,我们还是实现下面的代理方法
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info;
在这里可以获取视频的相关信息,我们主要是拿到视频路径并保存.
保存视频在ios8之后,需要用到PHPhotoLibrary类,需要引入这个头文件#import <Photos/Photos.h>
需要调用PHAssetChangeRequest 的类方法creationRequestForAssetFromVideoAtFileURL
保存视频,注意这个方法只能在performChanges方法中调用,否则会崩溃
将视频保存到图库的代码如下:
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info{
UIVideoEditorController *videoEditor = nil;
if ([info[UIImagePickerControllerMediaType] isEqualToString:(__bridge NSString *)kUTTypeMovie]) {
NSURL *URL = info[UIImagePickerControllerMediaURL];
//ios 9.0废弃
// ALAssetsLibrary *lib = [[ALAssetsLibrary alloc]init];
// [lib writeVideoAtPathToSavedPhotosAlbum:URL completionBlock:nil];
// "Use creationRequestForAssetFromVideoAtFilePath: on PHAssetChangeRequest from the Photos framework to create a new asset instead"
//ios 8.0+ 调用另外一个方法也可以,error也可以要传NULL
NSError *error;
[[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
[PHAssetChangeRequest creationRequestForAssetFromVideoAtFileURL:URL];
NSLog(@"%@",error);
} error:&error];
[picker dismissViewControllerAnimated:YES completion:^{
[self presentViewController:videoEditor animated:YES completion:nil];
}];
}
编辑并保存视频
截止到上一步我们已经完成了视频的录制和保存.保存视频需要用到UIVideoEditorController类,给他视频的路径,并present就可以出现编辑界面了,如果要保存结果,同样要给他设置结果.我们在上一个代理方法中继续编辑,代码如下:
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary<NSString *,id> *)info{
UIVideoEditorController *videoEditor = nil;
if ([info[UIImagePickerControllerMediaType] isEqualToString:(__bridge NSString *)kUTTypeMovie]) {
NSURL *URL = info[UIImagePickerControllerMediaURL];
//ios 9.0废弃
// ALAssetsLibrary *lib = [[ALAssetsLibrary alloc]init];
// [lib writeVideoAtPathToSavedPhotosAlbum:URL completionBlock:nil];
// "Use creationRequestForAssetFromVideoAtFilePath: on PHAssetChangeRequest from the Photos framework to create a new asset instead"
//ios 8.0+
NSError *error;
[[PHPhotoLibrary sharedPhotoLibrary] performChangesAndWait:^{
[PHAssetChangeRequest creationRequestForAssetFromVideoAtFileURL:URL];
NSLog(@"%@",error);
} error:&error];
if([UIVideoEditorController canEditVideoAtPath:URL.path]){
videoEditor = [[UIVideoEditorController alloc]init];
videoEditor.videoPath = URL.path;
videoEditor.delegate = self;
}
}
[picker dismissViewControllerAnimated:YES completion:^{
[self presentViewController:videoEditor animated:YES completion:nil];
}];
}
//下面这个是视频编辑控制器的代理方法
- (void)videoEditorController:(UIVideoEditorController *)editor didSaveEditedVideoToPath:(NSString *)editedVideoPath{
NSLog(@"%@",editedVideoPath);
[[PHPhotoLibrary sharedPhotoLibrary] performChanges:^{
[PHAssetChangeRequest creationRequestForAssetFromVideoAtFileURL:[NSURL fileURLWithPath:editedVideoPath]];
} completionHandler:^(BOOL success, NSError * _Nullable error) {
if (success) {
NSLog(@"保存成功");
}
if (error) {
NSLog(@"%@",error);
}
}];
[editor dismissViewControllerAnimated:YES completion:nil];
}
到这里,你已经学会了如果进行视频的录制保存和编辑了.
