@tensorflow/tfjs-core
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Hardware-accelerated JavaScript library for machine intelligence
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JavaScript
;
/**
* @license
* Copyright 2018 Google LLC. All Rights Reserved.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* =============================================================================
*/
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
return new (P || (P = Promise))(function (resolve, reject) {
function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
function step(result) { result.done ? resolve(result.value) : new P(function (resolve) { resolve(result.value); }).then(fulfilled, rejected); }
step((generator = generator.apply(thisArg, _arguments || [])).next());
});
};
var __generator = (this && this.__generator) || function (thisArg, body) {
var _ = { label: 0, sent: function() { if (t[0] & 1) throw t[1]; return t[1]; }, trys: [], ops: [] }, f, y, t, g;
return g = { next: verb(0), "throw": verb(1), "return": verb(2) }, typeof Symbol === "function" && (g[Symbol.iterator] = function() { return this; }), g;
function verb(n) { return function (v) { return step([n, v]); }; }
function step(op) {
if (f) throw new TypeError("Generator is already executing.");
while (_) try {
if (f = 1, y && (t = op[0] & 2 ? y["return"] : op[0] ? y["throw"] || ((t = y["return"]) && t.call(y), 0) : y.next) && !(t = t.call(y, op[1])).done) return t;
if (y = 0, t) op = [op[0] & 2, t.value];
switch (op[0]) {
case 0: case 1: t = op; break;
case 4: _.label++; return { value: op[1], done: false };
case 5: _.label++; y = op[1]; op = [0]; continue;
case 7: op = _.ops.pop(); _.trys.pop(); continue;
default:
if (!(t = _.trys, t = t.length > 0 && t[t.length - 1]) && (op[0] === 6 || op[0] === 2)) { _ = 0; continue; }
if (op[0] === 3 && (!t || (op[1] > t[0] && op[1] < t[3]))) { _.label = op[1]; break; }
if (op[0] === 6 && _.label < t[1]) { _.label = t[1]; t = op; break; }
if (t && _.label < t[2]) { _.label = t[2]; _.ops.push(op); break; }
if (t[2]) _.ops.pop();
_.trys.pop(); continue;
}
op = body.call(thisArg, _);
} catch (e) { op = [6, e]; y = 0; } finally { f = t = 0; }
if (op[0] & 5) throw op[1]; return { value: op[0] ? op[1] : void 0, done: true };
}
};
Object.defineProperty(exports, "__esModule", { value: true });
var tensor_ops_1 = require("../ops/tensor_ops");
var util_1 = require("../util");
var types_1 = require("./types");
/** Number of bytes reserved for the length of the string. (32bit integer). */
var NUM_BYTES_STRING_LENGTH = 4;
/**
* Encode a map from names to weight values as an ArrayBuffer, along with an
* `Array` of `WeightsManifestEntry` as specification of the encoded weights.
*
* This function does not perform sharding.
*
* This function is the reverse of `decodeWeights`.
*
* @param tensors A map ("dict") from names to tensors.
* @param group Group to which the weights belong (optional).
* @returns A `Promise` of
* - A flat `ArrayBuffer` with all the binary values of the `Tensor`s
* concatenated.
* - An `Array` of `WeightManifestEntry`s, carrying information including
* tensor names, `dtype`s and shapes.
* @throws Error: on unsupported tensor `dtype`.
*/
function encodeWeights(tensors, group) {
return __awaiter(this, void 0, void 0, function () {
var specs, dataPromises, names, _loop_1, i, tensorValues;
var _this = this;
return __generator(this, function (_a) {
switch (_a.label) {
case 0:
specs = [];
dataPromises = [];
names = Array.isArray(tensors) ?
tensors.map(function (tensor) { return tensor.name; }) :
Object.keys(tensors);
_loop_1 = function (i) {
var name_1 = names[i];
var t = Array.isArray(tensors) ? tensors[i].tensor : tensors[name_1];
if (t.dtype !== 'float32' && t.dtype !== 'int32' && t.dtype !== 'bool' &&
t.dtype !== 'string') {
throw new Error("Unsupported dtype in weight '" + name_1 + "': " + t.dtype);
}
var spec = { name: name_1, shape: t.shape, dtype: t.dtype };
if (t.dtype === 'string') {
var utf8bytes = new Promise(function (resolve) { return __awaiter(_this, void 0, void 0, function () {
var vals, totalNumBytes, bytes, offset, i_1, val, bytesOfLength;
return __generator(this, function (_a) {
switch (_a.label) {
case 0: return [4 /*yield*/, t.bytes()];
case 1:
vals = _a.sent();
totalNumBytes = vals.reduce(function (p, c) { return p + c.length; }, 0) +
NUM_BYTES_STRING_LENGTH * vals.length;
bytes = new Uint8Array(totalNumBytes);
offset = 0;
for (i_1 = 0; i_1 < vals.length; i_1++) {
val = vals[i_1];
bytesOfLength = new Uint8Array(new Uint32Array([val.length]).buffer);
bytes.set(bytesOfLength, offset);
offset += NUM_BYTES_STRING_LENGTH;
bytes.set(val, offset);
offset += val.length;
}
resolve(bytes);
return [2 /*return*/];
}
});
}); });
dataPromises.push(utf8bytes);
}
else {
dataPromises.push(t.data());
}
if (group != null) {
spec.group = group;
}
specs.push(spec);
};
for (i = 0; i < names.length; ++i) {
_loop_1(i);
}
return [4 /*yield*/, Promise.all(dataPromises)];
case 1:
tensorValues = _a.sent();
return [2 /*return*/, { data: concatenateTypedArrays(tensorValues), specs: specs }];
}
});
});
}
exports.encodeWeights = encodeWeights;
/**
* Decode flat ArrayBuffer as weights.
*
* This function does not handle sharding.
*
* This function is the reverse of `encodeWeights`.
*
* @param buffer A flat ArrayBuffer carrying the binary values of the tensors
* concatenated in the order specified in `specs`.
* @param specs Specifications of the names, dtypes and shapes of the tensors
* whose value are encoded by `buffer`.
* @return A map from tensor name to tensor value, with the names corresponding
* to names in `specs`.
* @throws Error, if any of the tensors has unsupported dtype.
*/
function decodeWeights(buffer, specs) {
// TODO(adarob, cais): Support quantization.
var out = {};
var offset = 0;
var _loop_2 = function (spec) {
var name_2 = spec.name;
var dtype = spec.dtype;
var shape = spec.shape;
var size = util_1.sizeFromShape(shape);
var values = void 0;
if ('quantization' in spec) {
var quantization_1 = spec.quantization;
if (quantization_1.dtype !== 'uint8' && quantization_1.dtype !== 'uint16') {
throw new Error("Weight " + spec.name + " has unknown " +
("quantization dtype " + quantization_1.dtype + ". ") +
"Supported quantization dtypes are: 'uint8' and 'uint16'.");
}
var quantizationSizeFactor = types_1.DTYPE_VALUE_SIZE_MAP[quantization_1.dtype];
var byteBuffer = buffer.slice(offset, offset + size * quantizationSizeFactor);
var quantizedArray = (quantization_1.dtype === 'uint8') ?
new Uint8Array(byteBuffer) :
new Uint16Array(byteBuffer);
if (dtype === 'float32') {
values = Float32Array.from(quantizedArray, function (v) { return v * quantization_1.scale + quantization_1.min; });
}
else if (dtype === 'int32') {
values = Int32Array.from(quantizedArray, function (v) { return Math.round(v * quantization_1.scale + quantization_1.min); });
}
else {
throw new Error("Unsupported dtype in weight '" + name_2 + "': " + dtype);
}
offset += size * quantizationSizeFactor;
}
else if (dtype === 'string') {
var size_1 = util_1.sizeFromShape(spec.shape);
values = [];
for (var i = 0; i < size_1; i++) {
var byteLength = new Uint32Array(buffer.slice(offset, offset + NUM_BYTES_STRING_LENGTH))[0];
offset += NUM_BYTES_STRING_LENGTH;
var bytes = new Uint8Array(buffer.slice(offset, offset + byteLength));
values.push(bytes);
offset += byteLength;
}
}
else {
var dtypeFactor = types_1.DTYPE_VALUE_SIZE_MAP[dtype];
var byteBuffer = buffer.slice(offset, offset + size * dtypeFactor);
if (dtype === 'float32') {
values = new Float32Array(byteBuffer);
}
else if (dtype === 'int32') {
values = new Int32Array(byteBuffer);
}
else if (dtype === 'bool') {
values = new Uint8Array(byteBuffer);
}
else {
throw new Error("Unsupported dtype in weight '" + name_2 + "': " + dtype);
}
offset += size * dtypeFactor;
}
out[name_2] = tensor_ops_1.tensor(values, shape, dtype);
};
for (var _i = 0, specs_1 = specs; _i < specs_1.length; _i++) {
var spec = specs_1[_i];
_loop_2(spec);
}
return out;
}
exports.decodeWeights = decodeWeights;
/**
* Concatenate TypedArrays into an ArrayBuffer.
*/
function concatenateTypedArrays(xs) {
// TODO(adarob, cais): Support quantization.
if (xs === null) {
throw new Error("Invalid input value: " + JSON.stringify(xs));
}
var totalByteLength = 0;
// `normalizedXs` is here for this reason: a `TypedArray`'s `buffer'
// can have a different byte length from that of the `TypedArray` itself,
// for example, when the `TypedArray` is created from an offset in an
// `ArrayBuffer`. `normliazedXs` holds `TypedArray`s whose `buffer`s match
// the `TypedArray` in byte length. If an element of `xs` does not show
// this property, a new `TypedArray` that satisfy this property will be
// constructed and pushed into `normalizedXs`.
var normalizedXs = [];
xs.forEach(function (x) {
totalByteLength += x.byteLength;
// tslint:disable:no-any
normalizedXs.push(x.byteLength === x.buffer.byteLength ? x :
new x.constructor(x));
if (!(x instanceof Float32Array || x instanceof Int32Array ||
x instanceof Uint8Array)) {
throw new Error("Unsupported TypedArray subtype: " + x.constructor.name);
}
// tslint:enable:no-any
});
var y = new Uint8Array(totalByteLength);
var offset = 0;
normalizedXs.forEach(function (x) {
y.set(new Uint8Array(x.buffer), offset);
offset += x.byteLength;
});
return y.buffer;
}
exports.concatenateTypedArrays = concatenateTypedArrays;
// Use Buffer on Node.js instead of Blob/atob/btoa
var useNodeBuffer = typeof Buffer !== 'undefined' &&
(typeof Blob === 'undefined' || typeof atob === 'undefined' ||
typeof btoa === 'undefined');
/**
* Calculate the byte length of a JavaScript string.
*
* Note that a JavaScript string can contain wide characters, therefore the
* length of the string is not necessarily equal to the byte length.
*
* @param str Input string.
* @returns Byte length.
*/
function stringByteLength(str) {
if (useNodeBuffer) {
return Buffer.byteLength(str);
}
return new Blob([str]).size;
}
exports.stringByteLength = stringByteLength;
/**
* Encode an ArrayBuffer as a base64 encoded string.
*
* @param buffer `ArrayBuffer` to be converted.
* @returns A string that base64-encodes `buffer`.
*/
function arrayBufferToBase64String(buffer) {
if (useNodeBuffer) {
return Buffer.from(buffer).toString('base64');
}
var buf = new Uint8Array(buffer);
var s = '';
for (var i = 0, l = buf.length; i < l; i++) {
s += String.fromCharCode(buf[i]);
}
return btoa(s);
}
exports.arrayBufferToBase64String = arrayBufferToBase64String;
/**
* Decode a base64 string as an ArrayBuffer.
*
* @param str Base64 string.
* @returns Decoded `ArrayBuffer`.
*/
function base64StringToArrayBuffer(str) {
if (useNodeBuffer) {
var buf = Buffer.from(str, 'base64');
return buf.buffer.slice(buf.byteOffset, buf.byteOffset + buf.byteLength);
}
var s = atob(str);
var buffer = new Uint8Array(s.length);
for (var i = 0; i < s.length; ++i) {
buffer.set([s.charCodeAt(i)], i);
}
return buffer.buffer;
}
exports.base64StringToArrayBuffer = base64StringToArrayBuffer;
/**
* Concatenate a number of ArrayBuffers into one.
*
* @param buffers A number of array buffers to concatenate.
* @returns Result of concatenating `buffers` in order.
*/
function concatenateArrayBuffers(buffers) {
var totalByteLength = 0;
buffers.forEach(function (buffer) {
totalByteLength += buffer.byteLength;
});
var temp = new Uint8Array(totalByteLength);
var offset = 0;
buffers.forEach(function (buffer) {
temp.set(new Uint8Array(buffer), offset);
offset += buffer.byteLength;
});
return temp.buffer;
}
exports.concatenateArrayBuffers = concatenateArrayBuffers;
/**
* Get the basename of a path.
*
* Behaves in a way analogous to Linux's basename command.
*
* @param path
*/
function basename(path) {
var SEPARATOR = '/';
path = path.trim();
while (path.endsWith(SEPARATOR)) {
path = path.slice(0, path.length - 1);
}
var items = path.split(SEPARATOR);
return items[items.length - 1];
}
exports.basename = basename;
/**
* Populate ModelArtifactsInfo fields for a model with JSON topology.
* @param modelArtifacts
* @returns A ModelArtifactsInfo object.
*/
function getModelArtifactsInfoForJSON(modelArtifacts) {
if (modelArtifacts.modelTopology instanceof ArrayBuffer) {
throw new Error('Expected JSON model topology, received ArrayBuffer.');
}
return {
dateSaved: new Date(),
modelTopologyType: 'JSON',
modelTopologyBytes: modelArtifacts.modelTopology == null ?
0 :
stringByteLength(JSON.stringify(modelArtifacts.modelTopology)),
weightSpecsBytes: modelArtifacts.weightSpecs == null ?
0 :
stringByteLength(JSON.stringify(modelArtifacts.weightSpecs)),
weightDataBytes: modelArtifacts.weightData == null ?
0 :
modelArtifacts.weightData.byteLength,
};
}
exports.getModelArtifactsInfoForJSON = getModelArtifactsInfoForJSON;
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