ACBAVPlayerExtension

是 AVPlayer 的一个扩展，将其转换为具有所有的 AVAudioPlayer 使用功能，并且支持流式传输。还添加了支持从 AVPlayer 流式传输的音频可视化的额外方法。这个扩展向 AVPlayer 添加了一些缺失的功能。

这个项目展示了一个简单的用法示例。ViewController 有一个 UIProgressView，它显示 averagePower 作为音量表，同时在 AVPlayer 中流式传输音频。这与我们通常使用 AVAudioPlayer 的方式非常相似，但添加了一些额外的功能，这使得显示 averagePower 更加容易。audioPCMBufferFetchedWithCallbackBlock 可以用来获取 AVAudioPCMBuffer，这可以用于音频可视化。添加了 stop 方法来停止播放器。

示例

设置

可以使用 Carthage 或 Cocoapods 将其集成到项目中。

Carthage

github "akhilcb/ACBAVPlayerExtension" ~> 2.1

Cocoapods

pod 'ACBAVPlayer'

AVPlayer 扩展接口

    @property (nonatomic, readonly, assign) int numberOfChannels;
    //stop video
    - (void)stop;
    
    /* metering */
    @property (nonatomic, getter=isMeteringEnabled) BOOL meteringEnabled; /* turns level metering on or off. default is off. */

    - (void)updateMeters; /* call to refresh meter values */
    - (float)peakPowerForChannel:(NSUInteger)channelNumber; /* for peak power in decibels for a given channel. returns average power for now */
    - (float)averagePowerForChannel:(NSUInteger)channelNumber; /* returns average power in decibels for a given channel */
    //use this to repeatedly fetch average power list(in decibels) for all channels in iMeteringCallbackBlock. This block will be executed each time a value is fetched. Index of array is channel number
    - (void)averagePowerListWithCallbackBlock:(ACBAVPlayerMeteringBlock)iMeteringCallbackBlock;
    - (float)averagePowerInLinearFormForChannel:(NSUInteger)channelNumber; //returns in average power in linear form. Value is in between 0 to 1.
    //fetch average power list in linear form(values in between 0 and 1)
    - (void)averagePowerListInLinearFormWithCallbackBlock:(ACBAVPlayerMeteringBlock)iMeteringCallbackBlock;
    //fetch AVAudioPCMBuffer. it has useful methods to manipuate buffers or to display a visualizer
    - (void)audioPCMBufferFetchedWithCallbackBlock:(ACBAVPlayerBufferFetchedBlock)iAudioBufferFetchedBlock;
    - (void)replaceCurrentItemAndUpdateMeteringForPlayerItem:(AVPlayerItem *)item; //use this instead of "replaceCurrentItemWithPlayerItem" for metering to work.

注意：这是一个测试版。可能会有一些问题（希望是次要的）。风险自负。

使用说明

    self.player = [[AVPlayer alloc] initWithURL:remoteURL];
    self.player.meteringEnabled = true;
    
    [self.player averagePowerListInLinearFormWithCallbackBlock:^(NSArray *iAvgPowerList, BOOL iSuccess) {
        if (iAvgPowerList.count > 0) {
            double power = [iAvgPowerList[0] doubleValue];
            if (iAvgPowerList.count > 1) {
                double secondPower = [iAvgPowerList[1] doubleValue];
                power = (power + secondPower) / 2;
            }
            dispatch_async(dispatch_get_main_queue(), ^{
                [self.progressBar setProgress:(power * 10)];
            });
        }
    }];

屏幕截图

许可证

MIT 许可协议

版权所有 (c) 2017, Akhil C Balan(https://github.com/akhilcb)

保留所有权利。