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How to use writePngChunk method in wpt

Best JavaScript code snippet using wpt

pdfjs.js

Source:pdfjs.js

...205    const data = new Uint8Array(pngLength);206    let offset = 0;207    data.set(PNG_HEADER, offset);208    offset += PNG_HEADER.length;209    writePngChunk('IHDR', ihdr, data, offset);210    offset += CHUNK_WRAPPER_SIZE + ihdr.length;211    writePngChunk('IDATA', idat, data, offset);212    offset += CHUNK_WRAPPER_SIZE + idat.length;213    writePngChunk('IEND', new Uint8Array(0), data, offset);214    return data;215    // return util.createObjectURL(data, 'image/png', forceDataSchema);216  }217  return function convertImgDataToPng (imgData, forceDataSchema, isMask) {218    const kind = (imgData.kind === undefined ? ImageKind.GRAYSCALE_1BPP : imgData.kind);219    return encode(imgData, kind, forceDataSchema, isMask);220  };221})();222module.exports = {223  convertImgDataToPng,...

helper.ts

Source:helper.ts

...81      crc = (crc >>> 8) ^ b;82    }83    return crc ^ -1;84  }85  function writePngChunk(type, body, data, offset) {86    let p = offset;87    const len = body.length;88    data[p] = (len >> 24) & 0xff;89    data[p + 1] = (len >> 16) & 0xff;90    data[p + 2] = (len >> 8) & 0xff;91    data[p + 3] = len & 0xff;92    p += 4;93    data[p] = type.charCodeAt(0) & 0xff;94    data[p + 1] = type.charCodeAt(1) & 0xff;95    data[p + 2] = type.charCodeAt(2) & 0xff;96    data[p + 3] = type.charCodeAt(3) & 0xff;97    p += 4;98    data.set(body, p);99    p += body.length;100    const crc = crc32(data, offset + 4, p);101    data[p] = (crc >> 24) & 0xff;102    data[p + 1] = (crc >> 16) & 0xff;103    data[p + 2] = (crc >> 8) & 0xff;104    data[p + 3] = crc & 0xff;105  }106  function deflateSync(literals) {107    let input;108    if (parseInt(process.versions.node, 10) >= 8) {109      input = literals;110    } else {111      input = new Buffer(literals);112    }113    const output = require('zlib').deflateSync(input, {114      level: 9,115    });116    return output instanceof Uint8Array ? output : new Uint8Array(output);117  }118  function encode(imgData, kind, isMask) {119    const { width, height, data: bytes } = imgData;120    let bitDepth;121    let colorType;122    let lineSize;123    switch (kind) {124      case ImageKind.GRAYSCALE_1BPP:125        colorType = 0;126        bitDepth = 1;127        lineSize = (width + 7) >> 3;128        break;129      case ImageKind.RGB_24BPP:130        colorType = 2;131        bitDepth = 8;132        lineSize = width * 3;133        break;134      case ImageKind.RGBA_32BPP:135        colorType = 6;136        bitDepth = 8;137        lineSize = width * 4;138        break;139      default:140        throw new Error('invalid format');141    }142    const literals = new Uint8Array((1 + lineSize) * height);143    let offsetLiterals = 0;144    let offsetBytes = 0;145    for (let y = 0; y < height; ++y) {146      literals[offsetLiterals++] = 0;147      literals.set(bytes.subarray(offsetBytes, offsetBytes + lineSize), offsetLiterals);148      offsetBytes += lineSize;149      offsetLiterals += lineSize;150    }151    if (kind === ImageKind.GRAYSCALE_1BPP && isMask) {152      offsetLiterals = 0;153      for (let _y = 0; _y < height; _y++) {154        offsetLiterals++;155        for (let _i3 = 0; _i3 < lineSize; _i3++) {156          literals[offsetLiterals++] ^= 0xff;157        }158      }159    }160    const ihdr = new Uint8Array([161      (width >> 24) & 0xff,162      (width >> 16) & 0xff,163      (width >> 8) & 0xff,164      width & 0xff,165      (height >> 24) & 0xff,166      (height >> 16) & 0xff,167      (height >> 8) & 0xff,168      height & 0xff,169      bitDepth,170      colorType,171      0x00,172      0x00,173      0x00,174    ]);175    const idat = deflateSync(literals);176    const pngLength = PNG_HEADER.length + CHUNK_WRAPPER_SIZE * 3 + ihdr.length + idat.length;177    const data = new Uint8Array(pngLength);178    let offset = 0;179    data.set(PNG_HEADER, offset);180    offset += PNG_HEADER.length;181    writePngChunk('IHDR', ihdr, data, offset);182    offset += CHUNK_WRAPPER_SIZE + ihdr.length;183    writePngChunk('IDATA', idat, data, offset);184    offset += CHUNK_WRAPPER_SIZE + idat.length;185    writePngChunk('IEND', new Uint8Array(0), data, offset);186    return data;187  }188  const kind = imgData.kind === undefined ? ImageKind.GRAYSCALE_1BPP : imgData.kind;189  return encode(imgData, kind, isMask);190};191export {192  pf,193  matrixToCoords,194  convertImgDataToPng,195  IDENTITY_MATRIX,196  FONT_IDENTITY_MATRIX,197  LINE_CAP_STYLES,198  LINE_JOIN_STYLES,199};

helpers.js

Source:helpers.js

...46    str.charCodeAt(2),47    str.charCodeAt(3)48  );49}50function writePngChunk(type, body, data, offset) {51  let p = offset;52  const len = body.length;53  p = writeNumber(data, p, len);54  p = writeChars(data, p, type);55  data.set(body, p);56  p += body.length;57  const crc = crc32(data, offset + 4, p);58  p = writeNumber(data, p, crc);59}60function deflateSync(literals) {61  const output = zlib.deflateSync(literals, { level: 9 });62  return output instanceof Uint8Array ? output : new Uint8Array(output);63}64function getKindParams(kind, width) {65  switch (kind) {66    case 2:67      return { colorType: 2, bitDepth: 8, lineSize: width * 3 };68    case 3:69      return { colorType: 6, bitDepth: 8, lineSize: width * 4 };70    default:71      return { colorType: 0, bitDepth: 1, lineSize: (width + 7) >> 3 };72  }73}74function convertImgDataToPng(imgData, isMask) {75  const kind = imgData.kind || 1;76  const { width, height } = imgData;77  const bytes = imgData.data;78  const { bitDepth, colorType, lineSize } = getKindParams(kind, width);79  const literals = new Uint8Array((1 + lineSize) * height);80  let offsetLiterals = 0;81  let offsetBytes = 0;82  for (let y = 0; y < height; y += 1) {83    literals[offsetLiterals] = 0;84    offsetLiterals += 1;85    literals.set(86      bytes.subarray(offsetBytes, offsetBytes + lineSize),87      offsetLiterals88    );89    offsetBytes += lineSize;90    offsetLiterals += lineSize;91  }92  if (kind === 1 && isMask) {93    offsetLiterals = 0;94    for (let y = 0; y < height; y += 1) {95      offsetLiterals += 1;96      for (let i = 0; i < lineSize; i += 1) {97        literals[offsetLiterals] ^= 0xff;98        offsetLiterals += 1;99      }100    }101  }102  const ihdr = new Uint8Array(13);103  writeNumber(ihdr, 0, width);104  writeNumber(ihdr, 4, height);105  ihdr[8] = bitDepth;106  ihdr[9] = colorType;107  const idat = deflateSync(literals);108  const pngLength =109    PNG_HEADER.length + CHUNK_WRAPPER_SIZE * 3 + ihdr.length + idat.length;110  const data = new Uint8Array(pngLength);111  let offset = 0;112  data.set(PNG_HEADER, offset);113  offset += PNG_HEADER.length;114  writePngChunk('IHDR', ihdr, data, offset);115  offset += CHUNK_WRAPPER_SIZE + ihdr.length;116  writePngChunk('IDATA', idat, data, offset);117  offset += CHUNK_WRAPPER_SIZE + idat.length;118  writePngChunk('IEND', new Uint8Array(0), data, offset);119  return data;120}121module.exports = {122  convertImgDataToPng,...

Using AI Code Generation

1var wptools = require('wp-tools');2wptools.writePngChunk('test.png', 'test', 'test', function(err) {3    if (err) {4        console.log(err);5    } else {6        console.log('Chunk written');7    }8});9var wptools = require('wp-tools');10wptools.readPngChunk('test.png', 'test', function(err, data) {11    if (err) {12        console.log(err);13    } else {14        console.log(data);15    }16});17var wptools = require('wp-tools');18wptools.removePngChunk('test.png', 'test', function(err) {19    if (err) {20        console.log(err);21    } else {22        console.log('Chunk removed');23    }24});25var wptools = require('wp-tools');26wptools.getPngChunks('test.png', function(err, chunks) {27    if (err) {28        console.log(err);29    } else {30        console.log(chunks);31    }32});33var wptools = require('wp-tools');34wptools.isPngChunkPresent('test.png', 'test', function(err, isPresent) {35    if (err) {36        console.log(err);37    } else {38        console.log(isPresent);39    }40});41var wptools = require('wp-tools');42wptools.getPngChunk('test.png', 'test', function(err, chunk) {43    if (err) {44        console.log(err);45    } else {46        console.log(chunk);47    }48});49var wptools = require('wp-tools');50wptools.getPngChunkData('test.png', 'test', function(err, data) {51    if (err) {52        console.log(err);53    } else {54        console.log(data);55    }56});57var wptools = require('wp-tools');58wptools.getJpegChunks('test.jpg', function(err, chunks) {

Using AI Code Generation

1const wptools = require('wp-tools');2const fs = require('fs');3const out = fs.createWriteStream('out.png');4const in = fs.createReadStream('in.png');5wptools.writePngChunk(in, out, 'test', 'test data', function(err) {6  if (err) {7    console.error(err);8    return;9  }10  console.log('done');11});

Using AI Code Generation

1var wptools = require('wp-tools');2var fs = require('fs');3var path = require('path');4var png = fs.readFileSync('test.png');5var chunk = {6};7var newPng = wptools.writePngChunk(png, chunk);8fs.writeFileSync('test2.png', newPng);9var wptools = require('wp-tools');10var fs = require('fs');11var path = require('path');12var png = fs.readFileSync('test2.png');13var chunk = wptools.readPngChunk(png, 'tEXt');14console.log(chunk);

Using AI Code Generation

1var wptools = require('wptools');2var fs = require('fs');3var png = fs.readFileSync('test.png');4var chunk = {5};6wptools.writePngChunk(png, chunk, function(err, newPng) {7    fs.writeFileSync('test-out.png', newPng);8});9var wptools = require('wptools');10var fs = require('fs');11var png = fs.readFileSync('test.png');12    {13    },14    {15    }16];17wptools.writePngChunks(png, chunks, function(err, newPng) {18    fs.writeFileSync('test-out.png', newPng);19});20var wptools = require('wptools');21var fs = require('fs');22var png = fs.readFileSync('test.png');23var chunk = {24};25wptools.writePngChunk(png, chunk, function(err, newPng) {26    fs.writeFileSync('test-out.png', newPng);27});28var wptools = require('wptools');29var fs = require('fs');30var png = fs.readFileSync('test.png');31    {32    },33    {34    }35];36wptools.writePngChunks(png, chunks,

Using AI Code Generation

1var wptools = require('wptools');2var png = new wptools.PNG();3png.readPngFile('test.png', function(err){4    if (err) {5        console.log('error reading file');6    }7    png.writePngChunk('tEXt', 'testchunk', 'testvalue', function(err){8        if (err) {9            console.log('error writing chunk');10        }11        png.writePngFile('test2.png', function(err){12            if (err) {13                console.log('error writing file');14            }15            console.log('done');16        });17    });18});19    function readPngChunk() {20        var png = new wptools.PNG();21        png.readPngFile('test.png', function(err){22            if (err) {23                console.log('error reading file');24            }25            png.readPngChunk('tEXt', 'testchunk', function(err, data){26                if (err) {27                    console.log('error reading chunk');28                }29                console.log('data = ' + data);30            });31        });32    }33<button onclick="readPngChunk()">Read chunk</button>34    function writePngChunk() {35        var png = new wptools.PNG();36        png.readPngFile('test.png', function(err){37            if (err) {38                console.log('error reading file');39            }40            png.writePngChunk('tEXt', 'testchunk', 'testvalue', function(err){41                if (err) {42                    console.log('error writing chunk');43                }44                png.writePngFile('test2.png', function(err){45                    if (err) {46                        console.log('error writing file');47                    }48                    console.log('done');

Using AI Code Generation

1var wptools = require('wp-tools');2var fs = require('fs');3var path = require('path');4var buffer = new Buffer(100);5buffer.write("Hello World",0,100);6var pngChunk = wptools.writePngChunk(buffer, "test");7fs.writeFileSync(path.join(__dirname, "test.png"), pngChunk);8var wptools = require('wp-tools');9var fs = require('fs');10var path = require('path');11var file = fs.readFileSync(path.join(__dirname, "test.png"));12var buffer = wptools.readPngChunk(file);13console.log(buffer.toString());14var wptools = require('wp-tools');15var fs = require('fs');16var path = require('path');17var buffer = new Buffer(100);18buffer.write("Hello World",0,100);19var pngChunk = wptools.writePngChunk(buffer, "test");20fs.writeFileSync(path.join(__dirname, "test.png"), pngChunk);21var wptools = require('wp-tools');22var fs = require('fs');23var path = require('path');24var file = fs.readFileSync(path.join(__dirname, "test.png"));25var buffer = wptools.readPngChunk(file);26console.log(buffer.toString());27var wptools = require('wp-tools');28var fs = require('fs');29var path = require('path');30var buffer = new Buffer(100);31buffer.write("Hello World",0,100);32var pngChunk = wptools.writePngChunk(buffer, "test");33fs.writeFileSync(path.join(__dirname, "test.png"), pngChunk);34var wptools = require('wp-tools');35var fs = require('fs');36var path = require('path');

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