| <!DOCTYPE html> |
| <html> |
| |
| <head> |
| <script src="../resources/js-test.js"></script> |
| <script src="resources/compatibility.js"></script> |
| <script src="resources/audio-testing.js"></script> |
| <script src="resources/merger-testing.js"></script> |
| </head> |
| |
| <body> |
| <script> |
| description('Test input handling behavior of ChannelMergerNode.'); |
| window.jsTestIsAsync = true; |
| |
| var audit = Audit.createTaskRunner(); |
| |
| // Task: Check if an inactive input renders a silent mono channel in the |
| // output. |
| audit.defineTask('silent-channel', function (done) { |
| testMergerInput({ |
| numberOfChannels: 6, |
| |
| // Create a mono source buffer filled with '1'. |
| testBufferContent: [1], |
| |
| // Connect the output of source into the 4th input of merger. |
| mergerInputIndex: 3, |
| |
| // All channels should contain 0, except channel 4 which should be 1. |
| expected: [0, 0, 0, 1, 0, 0], |
| }, done); |
| }); |
| |
| |
| // Task: Check if a stereo input is being down-mixed to mono channel |
| // correctly based on the mixing rule. |
| audit.defineTask('stereo-down-mixing', function (done) { |
| testMergerInput({ |
| numberOfChannels: 6, |
| |
| // Create a stereo buffer filled with '1' and '2' for left and right |
| // channels respectively. |
| testBufferContent: [1, 2], |
| |
| // Connect the output of source into the 1st input of merger. |
| mergerInputIndex: undefined, |
| |
| // The result of summed and down-mixed stereo audio should be 1.5. |
| // (= 1 * 0.5 + 2 * 0.5) |
| expected: [1.5, 0, 0, 0, 0, 0], |
| }, done); |
| }); |
| |
| |
| // Task: Check if 3-channel input gets processed by the 'discrete' mixing |
| // rule. |
| audit.defineTask('undefined-channel-layout', function (done) { |
| testMergerInput({ |
| numberOfChannels: 6, |
| |
| // Create a 3-channel buffer filled with '1', '2', and '3' respectively. |
| testBufferContent: [1, 2, 3], |
| |
| // Connect the output of source into the 1st input of merger. |
| mergerInputIndex: undefined, |
| |
| // The result of summed stereo audio should be 1 because 3-channel is |
| // not a canonical layout, so the input channel 2 and 3 should be |
| // dropped by 'discrete' mixing rule. |
| expected: [1, 0, 0, 0, 0, 0], |
| }, done); |
| }); |
| |
| |
| // Task: Merging two inputs into a single stereo stream. |
| audit.defineTask('merging-to-stereo', function (done) { |
| |
| // For this test, the number of channel should be 2. |
| var context = new OfflineAudioContext(2, 128, 44100); |
| var merger = context.createChannelMerger(); |
| var source1 = context.createBufferSource(); |
| var source2 = context.createBufferSource(); |
| |
| // Create a DC offset buffer (mono) filled with 1 and assign it to BS |
| // nodes. |
| var positiveDCOffset = createConstantBuffer(context, 128, 1); |
| var negativeDCOffset = createConstantBuffer(context, 128, -1); |
| source1.buffer = positiveDCOffset; |
| source2.buffer = negativeDCOffset; |
| |
| // Connect: BS#1 => merger_input#0, BS#2 => Inverter => merger_input#1 |
| source1.connect(merger, 0, 0); |
| source2.connect(merger, 0, 1); |
| merger.connect(context.destination); |
| source1.start(); |
| source2.start(); |
| |
| context.startRendering().then(function (buffer) { |
| |
| // Channel#0 = 1, Channel#1 = -1 |
| Should('Channel #0', buffer.getChannelData(0)).beConstantValueOf(1); |
| Should('Channel #1', buffer.getChannelData(1)).beConstantValueOf(-1); |
| |
| done(); |
| }); |
| }); |
| |
| |
| audit.defineTask('finish', function (done) { |
| finishJSTest(); |
| done(); |
| }); |
| |
| audit.runTasks( |
| 'silent-channel', |
| 'stereo-down-mixing', |
| 'undefined-channel-layout', |
| 'merging-to-stereo', |
| 'finish' |
| ); |
| |
| successfullyParsed = true; |
| </script> |
| </body> |
| |
| </html> |
