Question

我搜索了这个问题，但没有找到任何解决方案。

所以，我的问题是，我正在使用GPUImage将视频过滤器应用于视频文件。同时，该视频的声音没有播放。我知道在应用过滤器时GPUImage不支持声音播放。

那么，我该怎么做呢？

Answer 1

您可以通过添加GPUImageMovie.h这样的支持来实现声音播放。

在@property(readwrite, nonatomic) BOOL playSound;，

GPUImageMovie.m
在@interface GPUImageMovie ()中，像这样更新@interface GPUImageMovie() <AVPlayerItemOutputPullDelegate> { // Add this BOOL hasAudioTrack; ......... ........ // Add all below three lines AVPlayer *theAudioPlayer; CFAbsoluteTime startActualFrameTime; CGFloat currentVideoTime; }。
```
-(void)startProcessing
```
之后，在- (void)startProcessing { // Add this currentVideoTime = 0.0f; ..... ..... // Add this if (self.playSound) { [self setupSound]; } GPUImageMovie __block *blockSelf = self; [inputAsset loadValuesAsynchronouslyForKeys:[NSArray arrayWithObject:@"tracks"] completionHandler: ^{ runSynchronouslyOnVideoProcessingQueue(^{ ......... ......... // Add this startActualFrameTime = CFAbsoluteTimeGetCurrent() - currentVideoTime; ....... ....... }); }]; }方法中添加以下行。
```
-(AVAssetReader*)createAssetReader
```
再次，在- (AVAssetReader*)createAssetReader { ....... ....... BOOL shouldRecordAudioTrack = (([audioTracks count] > 0) && (self.audioEncodingTarget != nil)); // Add this hasAudioTrack = ([audioTracks count] > 0); ......... }更新它，
```
-(void)processAsset
```
在-(void)processAsset { ....... ....... if ([reader startReading] == NO) { NSLog(@"Error reading from file at URL: %@", self.url); return; } // Add this if (self.playSound && hasAudioTrack) { [theAudioPlayer seekToTime:kCMTimeZero]; [theAudioPlayer play]; } ......... ......... }，
```
-(void)endProcessing
```
在-(void) endProcessing { ......... ......... if (self.playerItem && (displayLink != nil)) { [displayLink invalidate]; // remove from all run loops displayLink = nil; } // Add this if (theAudioPlayer != nil) { [theAudioPlayer pause]; [theAudioPlayer seekToTime:kCMTimeZero]; } ......... ......... }，
```
-(void) setupSound
```
最后添加新方法// Add this - (void) setupSound { if (theAudioPlayer != nil) { [theAudioPlayer pause]; [theAudioPlayer seekToTime:kCMTimeZero]; theAudioPlayer = nil; } theAudioPlayer = [[AVPlayer alloc] initWithURL:self.url]; }，
```
GPUImageMovie
```
最后，当您创建playSound对象时，不要忘记将YES.标记设置为movieFile.playSound = YES;

像这样：SELECT * FROM Table1 WHERE [name] IN (SELECT name, Count(name) FROM Table1 GROUP BY name HAVING COUNT(name)>1)

希望这会有所帮助。

Answer 2

如何在 GPUImage ？

应用的过滤器中暂停音频

就像我暂停电影写作时我们可以暂停movieWriter.paused = YES;的视频写作一样，我也需要暂停音频。

在GPUImage中应用视频过滤器时播放音频

2 个答案: