将视频文件压缩保存mp4格式
AVURLAsset *avAsset = [AVURLAsset URLAssetWithURL:movieUrl options:nil];
NSArray *compatiblePresets = [AVAssetExportSession exportPresetsCompatibleWithAsset:avAsset];
if ([compatiblePresets containsObject:AVAssetExportPresetHighestQuality]) {
AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:avAsset presetName:AVAssetExportPresetMediumQuality];
NSDateFormatter *formater = [[NSDateFormatter alloc] init];
[formater setDateFormat:@"yyyy-MM-dd-HH:mm:ss"];
NSString * resultPath = [NSHomeDirectory() stringByAppendingFormat:@"/Documents/output-%@.mp4", [formater stringFromDate:[NSDate date]]];
exportSession.outputURL = [NSURL fileURLWithPath:resultPath]; exportSession.outputFileType = AVFileTypeMPEG4; exportSession.shouldOptimizeForNetworkUse = YES;
[exportSession exportAsynchronouslyWithCompletionHandler:^(void) {
switch (exportSession.status) {
case AVAssetExportSessionStatusUnknown:
NSLog(@"AVAssetExportSessionStatusUnknown");
break;
case AVAssetExportSessionStatusWaiting:
NSLog(@"AVAssetExportSessionStatusWaiting");
break;
case AVAssetExportSessionStatusExporting:
NSLog(@"AVAssetExportSessionStatusExporting");
break;
case AVAssetExportSessionStatusCompleted: NSLog(@"AVAssetExportSessionStatusCompleted");
break;
case AVAssetExportSessionStatusFailed: NSLog(@"AVAssetExportSessionStatusFailed");
break;
}
}];
}
问题补充
发现某些机子输出会失败exportSession.status=4 这时候可以找个第三方的库代替系统的AVAssetExportSession
SCAssetExportSession为例
SCAssetExportSession *exportSession = [[SCAssetExportSession alloc] initWithAsset:avAsset];
NSDateFormatter *formater = [[NSDateFormatter alloc] init];
[formater setDateFormat:@"yyyy-MM-dd-HH:mm:ss"];
NSString * resultPath = [NSHomeDirectory() stringByAppendingFormat:@"/Documents/%@.mp4", [formater stringFromDate:[NSDate date]]];
exportSession.videoConfiguration.preset = SCPresetLowQuality;
exportSession.audioConfiguration.preset = SCPresetLowQuality;
exportSession.videoConfiguration.maxFrameRate = 15;
exportSession.outputUrl = [NSURL fileURLWithPath:resultPath];
exportSession.outputFileType = AVFileTypeMPEG4;
[exportSession exportAsynchronouslyWithCompletionHandler:^(void){
[self sandToTXWith:resultPath];
}];
