void decodeIdat() { int nbitDepth = bitDepth; if (nbitDepth == 16) nbitDepth = 8; int size = -1; bytesPerPixel = (bitDepth == 16) ? 2 : 1; switch (colorType) { case 0: size = (nbitDepth * width + 7) / 8 * height; break; case 2: size = width * 3 * height; bytesPerPixel *= 3; break; case 3: if (interlaceMethod == 1) size = (nbitDepth * width + 7) / 8 * height; bytesPerPixel = 1; break; case 4: size = width * height; bytesPerPixel *= 2; break; case 6: size = width * 3 * height; bytesPerPixel *= 4; break; } if (size >= 0) image = new byte[size]; if (palShades) smask = new byte[width * height]; else if (genBWMask) smask = new byte[(width + 7) / 8 * height]; ByteArrayInputStream bai = new ByteArrayInputStream(idat.getBuf(), 0, idat.size()); InputStream infStream = new InflaterInputStream(bai, new Inflater()); dataStream = new DataInputStream(infStream); if (interlaceMethod != 1) { decodePass(0, 0, 1, 1, width, height); } else { decodePass(0, 0, 8, 8, (width + 7) / 8, (height + 7) / 8); decodePass(4, 0, 8, 8, (width + 3) / 8, (height + 7) / 8); decodePass(0, 4, 4, 8, (width + 3) / 4, (height + 3) / 8); decodePass(2, 0, 4, 4, (width + 1) / 4, (height + 3) / 4); decodePass(0, 2, 2, 4, (width + 1) / 2, (height + 1) / 4); decodePass(1, 0, 2, 2, width / 2, (height + 1) / 2); decodePass(0, 1, 1, 2, width, height / 2); } }
Image getImage() throws IOException { readPng(); try { int pal0 = 0; int palIdx = 0; palShades = false; if (trans != null) { for (int k = 0; k < trans.length; ++k) { int n = trans[k] & 0xff; if (n == 0) { ++pal0; palIdx = k; } if (n != 0 && n != 255) { palShades = true; break; } } } if ((colorType & 4) != 0) palShades = true; genBWMask = (!palShades && (pal0 > 1 || transRedGray >= 0)); if (!palShades && !genBWMask && pal0 == 1) { additional.put(PdfName.MASK, new PdfLiteral("[" + palIdx + " " + palIdx + "]")); } boolean needDecode = (interlaceMethod == 1) || (bitDepth == 16) || ((colorType & 4) != 0) || palShades || genBWMask; switch (colorType) { case 0: inputBands = 1; break; case 2: inputBands = 3; break; case 3: inputBands = 1; break; case 4: inputBands = 2; break; case 6: inputBands = 4; break; } if (needDecode) decodeIdat(); int components = inputBands; if ((colorType & 4) != 0) --components; int bpc = bitDepth; if (bpc == 16) bpc = 8; Image img; if (image != null) img = Image.getInstance(width, height, components, bpc, image); else { img = new ImgRaw(width, height, components, bpc, idat.toByteArray()); img.setDeflated(true); PdfDictionary decodeparms = new PdfDictionary(); decodeparms.put(PdfName.BITSPERCOMPONENT, new PdfNumber(bitDepth)); decodeparms.put(PdfName.PREDICTOR, new PdfNumber(15)); decodeparms.put(PdfName.COLUMNS, new PdfNumber(width)); decodeparms.put( PdfName.COLORS, new PdfNumber((colorType == 3 || (colorType & 2) == 0) ? 1 : 3)); additional.put(PdfName.DECODEPARMS, decodeparms); } if (additional.get(PdfName.COLORSPACE) == null) additional.put(PdfName.COLORSPACE, getColorspace()); if (intent != null) additional.put(PdfName.INTENT, intent); if (additional.size() > 0) img.setAdditional(additional); if (icc_profile != null) img.tagICC(icc_profile); if (palShades) { Image im2 = Image.getInstance(width, height, 1, 8, smask); im2.makeMask(); img.setImageMask(im2); } if (genBWMask) { Image im2 = Image.getInstance(width, height, 1, 1, smask); im2.makeMask(); img.setImageMask(im2); } img.setDpi(dpiX, dpiY); img.setXYRatio(XYRatio); img.setOriginalType(Image.ORIGINAL_PNG); return img; } catch (Exception e) { throw new ExceptionConverter(e); } }
void readPng() throws IOException { for (int i = 0; i < PNGID.length; i++) { if (PNGID[i] != is.read()) { throw new IOException("File is not a valid PNG."); } } byte buffer[] = new byte[TRANSFERSIZE]; while (true) { int len = getInt(is); String marker = getString(is); if (len < 0 || !checkMarker(marker)) throw new IOException("Corrupted PNG file."); if (IDAT.equals(marker)) { int size; while (len != 0) { size = is.read(buffer, 0, Math.min(len, TRANSFERSIZE)); if (size < 0) return; idat.write(buffer, 0, size); len -= size; } } else if (tRNS.equals(marker)) { switch (colorType) { case 0: if (len >= 2) { len -= 2; int gray = getWord(is); if (bitDepth == 16) transRedGray = gray; else additional.put(PdfName.MASK, new PdfLiteral("[" + gray + " " + gray + "]")); } break; case 2: if (len >= 6) { len -= 6; int red = getWord(is); int green = getWord(is); int blue = getWord(is); if (bitDepth == 16) { transRedGray = red; transGreen = green; transBlue = blue; } else additional.put( PdfName.MASK, new PdfLiteral( "[" + red + " " + red + " " + green + " " + green + " " + blue + " " + blue + "]")); } break; case 3: if (len > 0) { trans = new byte[len]; for (int k = 0; k < len; ++k) trans[k] = (byte) is.read(); len = 0; } break; } Utilities.skip(is, len); } else if (IHDR.equals(marker)) { width = getInt(is); height = getInt(is); bitDepth = is.read(); colorType = is.read(); compressionMethod = is.read(); filterMethod = is.read(); interlaceMethod = is.read(); } else if (PLTE.equals(marker)) { if (colorType == 3) { PdfArray colorspace = new PdfArray(); colorspace.add(PdfName.INDEXED); colorspace.add(getColorspace()); colorspace.add(new PdfNumber(len / 3 - 1)); ByteBuffer colortable = new ByteBuffer(); while ((len--) > 0) { colortable.append_i(is.read()); } colorspace.add(new PdfString(colorTable = colortable.toByteArray())); additional.put(PdfName.COLORSPACE, colorspace); } else { Utilities.skip(is, len); } } else if (pHYs.equals(marker)) { int dx = getInt(is); int dy = getInt(is); int unit = is.read(); if (unit == 1) { dpiX = (int) ((float) dx * 0.0254f + 0.5f); dpiY = (int) ((float) dy * 0.0254f + 0.5f); } else { if (dy != 0) XYRatio = (float) dx / (float) dy; } } else if (cHRM.equals(marker)) { xW = (float) getInt(is) / 100000f; yW = (float) getInt(is) / 100000f; xR = (float) getInt(is) / 100000f; yR = (float) getInt(is) / 100000f; xG = (float) getInt(is) / 100000f; yG = (float) getInt(is) / 100000f; xB = (float) getInt(is) / 100000f; yB = (float) getInt(is) / 100000f; hasCHRM = !(Math.abs(xW) < 0.0001f || Math.abs(yW) < 0.0001f || Math.abs(xR) < 0.0001f || Math.abs(yR) < 0.0001f || Math.abs(xG) < 0.0001f || Math.abs(yG) < 0.0001f || Math.abs(xB) < 0.0001f || Math.abs(yB) < 0.0001f); } else if (sRGB.equals(marker)) { int ri = is.read(); intent = intents[ri]; gamma = 2.2f; xW = 0.3127f; yW = 0.329f; xR = 0.64f; yR = 0.33f; xG = 0.3f; yG = 0.6f; xB = 0.15f; yB = 0.06f; hasCHRM = true; } else if (gAMA.equals(marker)) { int gm = getInt(is); if (gm != 0) { gamma = 100000f / (float) gm; if (!hasCHRM) { xW = 0.3127f; yW = 0.329f; xR = 0.64f; yR = 0.33f; xG = 0.3f; yG = 0.6f; xB = 0.15f; yB = 0.06f; hasCHRM = true; } } } else if (iCCP.equals(marker)) { do { --len; } while (is.read() != 0); is.read(); --len; byte icccom[] = new byte[len]; int p = 0; while (len > 0) { int r = is.read(icccom, p, len); if (r < 0) throw new IOException("Premature end of file."); p += r; len -= r; } byte iccp[] = PdfReader.FlateDecode(icccom, true); icccom = null; // try { // icc_profile = ICC_Profile.getInstance(iccp); // } // catch (Exception e) { icc_profile = null; // } } else if (IEND.equals(marker)) { break; } else { Utilities.skip(is, len); } Utilities.skip(is, 4); } }