annotate perf-test-node.js @ 36:34480328bf5c

Instead of using separate values and b64values entries in JSON serialisations, allow numeric arrays to be replaced by b64 variants wherever they appear (discriminating by type). Also rename values to featureValues in feature throughout, as values turns out to be a hazardous name in a JS context. Finally use Array instead of Text for array encoding (seems clearer).

"use strict";

var VampExamplePlugins = require("./VampExamplePlugins");
var base64 = require("./base64");
var exampleModule = VampExamplePlugins();

// It is possible to declare both parameters and return values as
// "string", in which case Emscripten will take care of
// conversions. But it's not clear how one would manage memory for
// newly-constructed returned C strings -- the returned pointer from
// vampipeRequestJson would appear (?) to be thrown away by the
// Emscripten string converter if we declare it as returning a string,
// so we have no opportunity to pass it to vampipeFreeJson, which
// suggests this would leak memory if the string isn't static. Not
// wholly sure though. Anyway, passing and returning pointers (as
// numbers) means we can manage the Emscripten heap memory however we
// want in our request wrapper function below.

var vampipeRequestJson = exampleModule.cwrap(
    'vampipeRequestJson', 'number', ['number']
);

var vampipeProcessRaw = exampleModule.cwrap(
    "vampipeProcessRaw", "number", ["number", "number", "number", "number"]
);

var vampipeFreeJson = exampleModule.cwrap(
    'vampipeFreeJson', 'void', ['number']
);

function note(blah) {
    console.log(blah);
}

function comment(blah) {
    console.log(blah);
}

function processRaw(request) {
    
    const nChannels = request.processInput.inputBuffers.length;
    const nFrames = request.processInput.inputBuffers[0].length;

    const buffersPtr = exampleModule._malloc(nChannels * 4);
    const buffers = new Uint32Array(
        exampleModule.HEAPU8.buffer, buffersPtr, nChannels);

    for (let i = 0; i < nChannels; ++i) {
        const framesPtr = exampleModule._malloc(nFrames * 4);
        const frames = new Float32Array(
            exampleModule.HEAPU8.buffer, framesPtr, nFrames);
        frames.set(request.processInput.inputBuffers[i]);
        buffers[i] = framesPtr;
    }
    
    const responseJson = vampipeProcessRaw(
        request.pluginHandle,
        buffersPtr,
        request.processInput.timestamp.s,
        request.processInput.timestamp.n);
    
    for (let i = 0; i < nChannels; ++i) {
        exampleModule._free(buffers[i]);
    }
    exampleModule._free(buffersPtr);

    const responseJstr = exampleModule.Pointer_stringify(responseJson);
    const response = JSON.parse(responseJstr);
    
    vampipeFreeJson(responseJson);
    
    return response;
}

function makeTimestamp(seconds) {
    if (seconds >= 0.0) {
        return {
            s: Math.floor(seconds),
            n: Math.floor((seconds - Math.floor(seconds)) * 1e9 + 0.5)
        };
    } else {
        const { s, n } = makeTimestamp(-seconds);
        return { s: -s, n: -n };
    }
}

function frame2timestamp(frame, rate) {
    return makeTimestamp(frame / rate);
}

function request(jsonStr) {
    note("Request JSON = " + jsonStr);
    var m = exampleModule;
    // Inspection reveals that intArrayFromString converts the string
    // from utf16 to utf8, which is what we want (though the docs
    // don't mention this). Note the *Cstr values are Emscripten heap
    // pointers
    var inCstr = m.allocate(m.intArrayFromString(jsonStr), 'i8', m.ALLOC_NORMAL);
    var outCstr = vampipeRequestJson(inCstr);
    m._free(inCstr);
    var result = m.Pointer_stringify(outCstr);
    vampipeFreeJson(outCstr);
    note("Returned JSON = " + result);
    return result;
}

function myFromBase64(b64) {
    while (b64.length % 4 > 0) { b64 += "="; }
    let conv = new Float32Array(base64.toByteArray(b64).buffer);
    return conv;
}

function convertWireFeature(wfeature) {
    let out = {};
    if (wfeature.timestamp != null) {
        out.timestamp = wfeature.timestamp;
    }
    if (wfeature.duration != null) {
        out.duration = wfeature.duration;
    }
    if (wfeature.label != null) {
        out.label = wfeature.label;
    }
    const vv = wfeature.featureValues;
    if (vv != null) {
        if (typeof vv === "string") {
            out.featureValues = myFromBase64(vv);
        } else {
            out.featureValues = new Float32Array(vv);
        }
    }
    return out;
}

function convertWireFeatureList(wfeatures) {
    return wfeatures.map(convertWireFeature);
}

function responseToFeatureSet(response) {
    const features = new Map();
    const processResponse = response.content;
    const wireFeatures = processResponse.features;
    Object.keys(wireFeatures).forEach(key => {
        return features.set(key, convertWireFeatureList(wireFeatures[key]));
    });
    return features;
}

function test() {

    const rate = 44100;
    
    comment("Loading zero crossings plugin...");
    let result = request('{"type":"load","content": {"pluginKey":"vamp-example-plugins:zerocrossing","inputSampleRate":' + rate + ',"adapterFlags":["AdaptAllSafe"]}}');

    const blockSize = 1024;

    result = request('{"type":"configure","content":{"pluginHandle":1,"configuration":{"blockSize": ' + blockSize + ', "channelCount": 1, "stepSize": ' + blockSize + '}}}');

    const nblocks = 1000;

    const makeBlock = (n => { 
        return {
            timestamp : frame2timestamp(n * blockSize, rate),
            inputBuffers : [
                new Float32Array(Array.from(Array(blockSize).keys(),
                                            n => n / blockSize))
            ],
        }
    });
    
    const blocks = Array.from(Array(nblocks).keys(), makeBlock);
    
    comment("Now processing " + nblocks + " blocks of 1024 samples each...");

    let total = 0;
    
    let start = (new Date()).getTime();
    comment("Start at " + start);
    
    for (let i = 0; i < nblocks; ++i) {
	result = processRaw({
	    "pluginHandle": 1,
	    "processInput": blocks[i]
	});
        let features = responseToFeatureSet(result);
        let count = features.get("counts")[0].featureValues[0];
        total += count;
    }

    let finish = (new Date()).getTime();
    comment("Finish at " + finish + " for a time of " + (finish - start) + " ms");

    comment("Total = " + total);

    comment("Again...");

    total = 0;
    
    start = (new Date()).getTime();
    comment("Start at " + start);
    
    for (let i = 0; i < nblocks; ++i) {
	result = processRaw({
	    "pluginHandle": 1,
	    "processInput": blocks[i]
	});
        let features = responseToFeatureSet(result);
        let count = features.get("counts")[0].featureValues[0];
        total += count;
    }

    finish = (new Date()).getTime();
    comment("Finish at " + finish + " for a time of " + (finish - start) + " ms");
    
    comment("Total = " + total);
    
    comment("Cleaning up the plugin and getting any remaining features...");
    result = request('{"type":"finish","content":{"pluginHandle":1}}');
}

test();