retrospective-test.js (1073B)
1 // Create an audio graph on an offline context that consists of a 2 // constant source and two gain nodes. One of the nodes is the node te 3 // be tested and the other is the reference node. The output from the 4 // test node is in channel 0 of the offline context; the reference 5 // node is in channel 1. 6 // 7 // Returns a dictionary with the context, source node, the test node, 8 // and the reference node. 9 function setupRetrospectiveGraph() { 10 // Use a sample rate that is a power of two to eliminate round-off 11 // in computing the currentTime. 12 let context = new OfflineAudioContext(2, 16384, 16384); 13 let source = new ConstantSourceNode(context); 14 15 let test = new GainNode(context); 16 let reference = new GainNode(context); 17 18 source.connect(test); 19 source.connect(reference); 20 21 let merger = new ChannelMergerNode( 22 context, {numberOfInputs: context.destination.channelCount}); 23 test.connect(merger, 0, 0); 24 reference.connect(merger, 0, 1); 25 26 merger.connect(context.destination); 27 28 return {context: context, source: source, test: test, reference: reference}; 29 }