Merge pull request rs#25 from hakanw/audio_only

Make audio-only exporting work
Ktoyta · Apr 17, 2015 · 088a9f0 · 088a9f0
2 parents 0694f73 + 05ac9ec
commit 088a9f0
Showing 1 changed file with 57 additions and 45 deletions.
diff --git a/SDAVAssetExportSession.m b/SDAVAssetExportSession.m
@@ -112,39 +112,41 @@ - (void)exportAsynchronouslyWithCompletionHandler:(void (^)())handler
     //
     // Video output
     //
-    self.videoOutput = [AVAssetReaderVideoCompositionOutput assetReaderVideoCompositionOutputWithVideoTracks:videoTracks videoSettings:nil];
-    self.videoOutput.alwaysCopiesSampleData = NO;
-    if (self.videoComposition)
-    {
-        self.videoOutput.videoComposition = self.videoComposition;
-    }
-    else
-    {
-        self.videoOutput.videoComposition = [self buildDefaultVideoComposition];
-    }
-    if ([self.reader canAddOutput:self.videoOutput])
-    {
-        [self.reader addOutput:self.videoOutput];
-    }
+    if (videoTracks.count > 0) {
+        self.videoOutput = [AVAssetReaderVideoCompositionOutput assetReaderVideoCompositionOutputWithVideoTracks:videoTracks videoSettings:nil];
+        self.videoOutput.alwaysCopiesSampleData = NO;
+        if (self.videoComposition)
+        {
+            self.videoOutput.videoComposition = self.videoComposition;
+        }
+        else
+        {
+            self.videoOutput.videoComposition = [self buildDefaultVideoComposition];
+        }
+        if ([self.reader canAddOutput:self.videoOutput])
+        {
+            [self.reader addOutput:self.videoOutput];
+        }
 
-    //
-    // Video input
-    //
-    self.videoInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:self.videoSettings];
-    self.videoInput.expectsMediaDataInRealTime = NO;
-    if ([self.writer canAddInput:self.videoInput])
-    {
-        [self.writer addInput:self.videoInput];
+        //
+        // Video input
+        //
+        self.videoInput = [AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeVideo outputSettings:self.videoSettings];
+        self.videoInput.expectsMediaDataInRealTime = NO;
+        if ([self.writer canAddInput:self.videoInput])
+        {
+            [self.writer addInput:self.videoInput];
+        }
+        NSDictionary *pixelBufferAttributes = @
+        {
+            (id)kCVPixelBufferPixelFormatTypeKey: @(kCVPixelFormatType_32BGRA),
+            (id)kCVPixelBufferWidthKey: @(renderSize.width),
+            (id)kCVPixelBufferHeightKey: @(renderSize.height),
+            @"IOSurfaceOpenGLESTextureCompatibility": @YES,
+            @"IOSurfaceOpenGLESFBOCompatibility": @YES,
+        };
+        self.videoPixelBufferAdaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput:self.videoInput sourcePixelBufferAttributes:pixelBufferAttributes];
     }
-    NSDictionary *pixelBufferAttributes = @
-    {
-        (id)kCVPixelBufferPixelFormatTypeKey: @(kCVPixelFormatType_32BGRA),
-        (id)kCVPixelBufferWidthKey: @(renderSize.width),
-        (id)kCVPixelBufferHeightKey: @(renderSize.height),
-        @"IOSurfaceOpenGLESTextureCompatibility": @YES,
-        @"IOSurfaceOpenGLESFBOCompatibility": @YES,
-    };
-    self.videoPixelBufferAdaptor = [AVAssetWriterInputPixelBufferAdaptor assetWriterInputPixelBufferAdaptorWithAssetWriterInput:self.videoInput sourcePixelBufferAttributes:pixelBufferAttributes];
 
     //
     //Audio output
@@ -177,26 +179,34 @@ - (void)exportAsynchronouslyWithCompletionHandler:(void (^)())handler
 
     [self.writer startWriting];
     [self.reader startReading];
-    [self.writer startSessionAtSourceTime:CMTimeMake(0, ((AVAssetTrack *)videoTracks[0]).naturalTimeScale)];
+    if (videoTracks.count > 0)
+        [self.writer startSessionAtSourceTime:CMTimeMake(0, ((AVAssetTrack *)videoTracks[0]).naturalTimeScale)];
+    else
+        [self.writer startSessionAtSourceTime:CMTimeMake(0, ((AVAssetTrack *)audioTracks[0]).naturalTimeScale)];        
 
-    self.inputQueue = dispatch_queue_create("VideoEncoderInputQueue", DISPATCH_QUEUE_SERIAL);
     __block BOOL videoCompleted = NO;
     __block BOOL audioCompleted = NO;
     __weak typeof(self) wself = self;
-    [self.videoInput requestMediaDataWhenReadyOnQueue:self.inputQueue usingBlock:^
-    {
-        if (![wself encodeReadySamplesFromOutput:wself.videoOutput toInput:wself.videoInput])
+    self.inputQueue = dispatch_queue_create("VideoEncoderInputQueue", DISPATCH_QUEUE_SERIAL);
+    if (videoTracks.count > 0) {
+        [self.videoInput requestMediaDataWhenReadyOnQueue:self.inputQueue usingBlock:^
         {
-            @synchronized(wself)
+            if (![wself encodeReadySamplesFromOutput:wself.videoOutput toInput:wself.videoInput])
             {
-                videoCompleted = YES;
-                if (audioCompleted)
+                @synchronized(wself)
                 {
-                    [wself finish];
+                    videoCompleted = YES;
+                    if (audioCompleted)
+                    {
+                        [wself finish];
+                    }
                 }
             }
-        }
-    }];
+        }];
+    }
+    else {
+        videoCompleted = YES;
+    }
 
     if (!self.audioOutput) {
         audioCompleted = YES;
@@ -233,12 +243,14 @@ - (BOOL)encodeReadySamplesFromOutput:(AVAssetReaderOutput *)output toInput:(AVAs
                 handled = YES;
                 error = YES;
             }
-
-            if (!handled && self.videoOutput == output)
-            {
+
+            if (!handled) {
                 lastSamplePresentationTime = CMSampleBufferGetPresentationTimeStamp(sampleBuffer);
                 self.progress = duration == 0 ? 1 : CMTimeGetSeconds(lastSamplePresentationTime) / duration;
+            }
 
+            if (!handled && self.videoOutput == output)
+            {
                 if ([self.delegate respondsToSelector:@selector(exportSession:renderFrame:withPresentationTime:toBuffer:)])
                 {
                     CVPixelBufferRef pixelBuffer = (CVPixelBufferRef)CMSampleBufferGetImageBuffer(sampleBuffer);