Mercurial > projects > dwt-win
view dwt/internal/image/PngEncoder.d @ 2:57151e2793a2
More common modules from dwt-linux
author | Frank Benoit <benoit@tionex.de> |
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date | Wed, 23 Jan 2008 12:01:46 +0100 |
parents | |
children | 36f5cb12e1a2 |
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/******************************************************************************* * Copyright (c) 2000, 2006 IBM Corporation and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * Contributors: * IBM Corporation - initial API and implementation * Port to the D programming language: * Frank Benoit <benoit@tionex.de> *******************************************************************************/ module dwt.internal.image.PngEncoder; import dwt.internal.image.LEDataOutputStream; import dwt.internal.image.PngDeflater; import dwt.dwthelper.ByteArrayOutputStream; import dwt.DWT; import dwt.graphics.ImageData; import dwt.graphics.ImageLoader; import dwt.graphics.RGB; import dwt.internal.image.PngChunk; import tango.core.Exception; final class PngEncoder { static const byte SIGNATURE[] = [cast(byte) '\211', cast(byte) 'P', cast(byte) 'N', cast(byte) 'G', cast(byte) '\r', cast(byte) '\n', cast(byte) '\032', cast(byte) '\n']; static const byte TAG_IHDR[] = [cast(byte) 'I', cast(byte) 'H', cast(byte) 'D', cast(byte) 'R']; static const byte TAG_PLTE[] = [cast(byte) 'P', cast(byte) 'L', cast(byte) 'T', cast(byte) 'E']; static const byte TAG_TRNS[] = [cast(byte) 't', cast(byte) 'R', cast(byte) 'N', cast(byte) 'S']; static const byte TAG_IDAT[] = [cast(byte) 'I', cast(byte) 'D', cast(byte) 'A', cast(byte) 'T']; static const byte TAG_IEND[] = [cast(byte) 'I', cast(byte) 'E', cast(byte) 'N', cast(byte) 'D']; ByteArrayOutputStream bytes; PngChunk chunk; ImageLoader loader; ImageData data; int transparencyType; int width, height, bitDepth, colorType; int compressionMethod = 0; int filterMethod = 0; int interlaceMethod = 0; public this(ImageLoader loader) { this.bytes = new ByteArrayOutputStream(1024); this.loader = loader; this.data = loader.data[0]; this.transparencyType = data.getTransparencyType(); this.width = data.width; this.height = data.height; this.bitDepth = 8; this.colorType = 2; if (data.palette.isDirect) { if (transparencyType is DWT.TRANSPARENCY_ALPHA) { this.colorType = 6; } } else { this.colorType = 3; } if (!(colorType is 2 || colorType is 3 || colorType is 6)) DWT.error(DWT.ERROR_INVALID_IMAGE); } void writeShort(ByteArrayOutputStream baos, int theShort) { byte byte1 = cast(byte) ((theShort >> 8) & 0xff); byte byte2 = cast(byte) (theShort & 0xff); byte[] temp = [byte1, byte2]; baos.write(temp, 0, 2); } void writeInt(ByteArrayOutputStream baos, int theInt) { byte byte1 = cast(byte) ((theInt >> 24) & 0xff); byte byte2 = cast(byte) ((theInt >> 16) & 0xff); byte byte3 = cast(byte) ((theInt >> 8) & 0xff); byte byte4 = cast(byte) (theInt & 0xff); byte[] temp = [byte1, byte2, byte3, byte4]; baos.write(temp, 0, 4); } void writeChunk(byte[] tag, byte[] buffer) { int bufferLength = (buffer !is null) ? buffer.length : 0; chunk = new PngChunk(bufferLength); writeInt(bytes, bufferLength); bytes.write(tag, 0, 4); chunk.setType(tag); if (bufferLength !is 0) { bytes.write(buffer, 0, bufferLength); chunk.setData(buffer); } else { chunk.setCRC(chunk.computeCRC()); } writeInt(bytes, chunk.getCRC()); } void writeSignature() { bytes.write(SIGNATURE, 0, 8); } void writeHeader() { ByteArrayOutputStream baos = new ByteArrayOutputStream(13); writeInt(baos, width); writeInt(baos, height); baos.write(bitDepth); baos.write(colorType); baos.write(compressionMethod); baos.write(filterMethod); baos.write(interlaceMethod); writeChunk(TAG_IHDR, baos.toByteArray()); } void writePalette() { RGB[] RGBs = data.palette.getRGBs(); if (RGBs.length > 256) DWT.error(DWT.ERROR_INVALID_IMAGE); ByteArrayOutputStream baos = new ByteArrayOutputStream(RGBs.length); for (int i = 0; i < RGBs.length; i++) { baos.write(cast(byte) RGBs[i].red); baos.write(cast(byte) RGBs[i].green); baos.write(cast(byte) RGBs[i].blue); } writeChunk(TAG_PLTE, baos.toByteArray()); } void writeTransparency() { ByteArrayOutputStream baos = new ByteArrayOutputStream(); switch (transparencyType) { case DWT.TRANSPARENCY_ALPHA: int pixelValue, alphaValue; byte[] alphas = new byte[data.palette.getRGBs().length]; for (int y = 0; y < height; y++) { for (int x = 0; x < width; x++) { pixelValue = data.getPixel(x, y); alphaValue = data.getAlpha(x, y); alphas[pixelValue] = cast(byte) alphaValue; } } baos.write(alphas, 0, alphas.length); break; case DWT.TRANSPARENCY_PIXEL: int pixel = data.transparentPixel; if (colorType is 2) { int redMask = data.palette.redMask; int redShift = data.palette.redShift; int greenMask = data.palette.greenMask; int greenShift = data.palette.greenShift; int blueShift = data.palette.blueShift; int blueMask = data.palette.blueMask; int r = pixel & redMask; r = (redShift < 0) ? r >>> -redShift : r << redShift; int g = pixel & greenMask; g = (greenShift < 0) ? g >>> -greenShift : g << greenShift; int b = pixel & blueMask; b = (blueShift < 0) ? b >>> -blueShift : b << blueShift; writeShort(baos, r); writeShort(baos, g); writeShort(baos, b); } if (colorType is 3) { byte[] padding = new byte[pixel + 1]; for (int i = 0; i < pixel; i++) { padding[i] = cast(byte) 255; } padding[pixel] = cast(byte) 0; baos.write(padding, 0, padding.length); } break; default: } writeChunk(TAG_TRNS, baos.toByteArray()); } void writeImageData() { ByteArrayOutputStream baos = new ByteArrayOutputStream(1024); if (colorType is 3) { int[] lineData = new int[width]; for (int y = 0; y < height; y++) { byte filter[] = [0]; baos.write(filter, 0, 1); data.getPixels(0, y, width, lineData, 0); for (int x = 0; x < lineData.length; x++) { baos.write(cast(byte) lineData[x]); } } } else { int[] lineData = new int[width]; byte[] alphaData = new byte[width]; int redMask = data.palette.redMask; int redShift = data.palette.redShift; int greenMask = data.palette.greenMask; int greenShift = data.palette.greenShift; int blueShift = data.palette.blueShift; int blueMask = data.palette.blueMask; for (int y = 0; y < height; y++) { byte filter[] = [0]; baos.write(filter, 0, 1); data.getPixels(0, y, width, lineData, 0); if (colorType is 6) { data.getAlphas(0, y, width, alphaData, 0); } for (int x = 0; x < lineData.length; x++) { int pixel = lineData[x]; int r = pixel & redMask; r = (redShift < 0) ? r >>> -redShift : r << redShift; int g = pixel & greenMask; g = (greenShift < 0) ? g >>> -greenShift : g << greenShift; int b = pixel & blueMask; b = (blueShift < 0) ? b >>> -blueShift : b << blueShift; byte pixels[] = [cast(byte) r, cast(byte) g, cast(byte) b]; baos.write(pixels, 0, 3); if (colorType is 6) { byte alpha[] = [alphaData[x]]; baos.write(alpha, 0, 1); } } } } PngDeflater deflater = new PngDeflater(); byte[] compressed = deflater.deflate(baos.toByteArray()); writeChunk(TAG_IDAT, compressed); } void writeEnd() { writeChunk(TAG_IEND, null); } public void encode(LEDataOutputStream outputStream) { try { writeSignature(); writeHeader(); if (colorType is 3) { writePalette(); } bool transparencyAlpha = (transparencyType is DWT.TRANSPARENCY_ALPHA); bool transparencyPixel = (transparencyType is DWT.TRANSPARENCY_PIXEL); bool type2Transparency = (colorType is 2 && transparencyPixel); bool type3Transparency = (colorType is 3 && (transparencyAlpha || transparencyPixel)); if (type2Transparency || type3Transparency) { writeTransparency(); } writeImageData(); writeEnd(); outputStream.write(bytes.toByteArray()); } catch (IOException e) { DWT.error(DWT.ERROR_IO, e); } } }