MPMoviePlayerController慢速前进和后退运动

Bow*_*was 4 iphone video xcode mpmovieplayercontroller ios

可能重复:
以2x 3x 4x速度播放/转发视频 - iPhone SDK

我目前正在开发基于视频的应用程序.我正在MPMoviePlayerController播放我在应用中录制的视频.我的问题是我需要做什么才能在慢速前进和后退运动中播放视频MPMoviePlayerController

Dhr*_*ruv 5

-(IBAction) playSlow:(UIButton *)sender{

    if (frameRate > 1) 
        frameRate -= 0.5;
    else
        frameRate -= 0.25;

    if (frameRate < 0) {
        frameRate=0;
    }

    queuePlayer.rate = frameRate;
}

-(IBAction) playFast:(UIButton *)sender{

    if (frameRate < 1) 
        frameRate += 0.25;
    else
        frameRate += 0.50;

    if(frameRate > 4)
        frameRate = 4;
    queuePlayer.rate = frameRate;
}
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