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src/java.desktop/share/classes/com/sun/imageio/plugins/png/PNGImageReader.java

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*** 696,709 **** } readHeader(); /* ! * Optimization: We can skip the remaining metadata if the ! * ignoreMetadata flag is set, and only if this is not a palette ! * image (in that case, we need to read the metadata to get the ! * tRNS chunk, which is needed for the getImageTypes() method). */ int colorType = metadata.IHDR_colorType; if (ignoreMetadata && colorType != PNG_COLOR_PALETTE) { try { while (true) { --- 696,711 ---- } readHeader(); /* ! * Optimization: We can skip reading metadata if ignoreMetadata ! * flag is set and colorType is not PNG_COLOR_PALETTE. However, ! * we parse tRNS chunk to retrieve the transparent color from the ! * metadata. Doing so, helps PNGImageReader to appropriately ! * identify and set transparent pixels in the decoded image for ! * colorType PNG_COLOR_RGB and PNG_COLOR_GRAY. */ int colorType = metadata.IHDR_colorType; if (ignoreMetadata && colorType != PNG_COLOR_PALETTE) { try { while (true) {
*** 715,728 **** } int chunkType = stream.readInt(); if (chunkType == IDAT_TYPE) { ! // We've reached the image data stream.skipBytes(-8); imageStartPosition = stream.getStreamPosition(); break; } else { // Skip the chunk plus the 4 CRC bytes that follow stream.skipBytes(chunkLength + 4); } } --- 717,739 ---- } int chunkType = stream.readInt(); if (chunkType == IDAT_TYPE) { ! // We've reached the first IDAT chunk position stream.skipBytes(-8); imageStartPosition = stream.getStreamPosition(); + /* + * According to PNG specification tRNS chunk must + * precede the first IDAT chunk. So we can stop + * reading metadata. + */ break; + } else if (chunkType == tRNS_TYPE) { + parse_tRNS_chunk(chunkLength); + // After parsing tRNS chunk we will skip 4 CRC bytes + stream.skipBytes(4); } else { // Skip the chunk plus the 4 CRC bytes that follow stream.skipBytes(chunkLength + 4); } }
*** 1264,1274 **** } if (dstY > dstMaxY) { break; } ! if (useSetRect) { imRas.setRect(updateMinX, dstY, passRow); } else { int newSrcX = srcX; for (int dstX = updateMinX; --- 1275,1302 ---- } if (dstY > dstMaxY) { break; } ! /* ! * In case of colortype PNG_COLOR_RGB or PNG_COLOR_GRAY ! * if we have transparent pixel information from tRNS chunk ! * we need to consider that also and store proper information ! * in alpha channel. ! * ! * Also we create destination image with extra alpha channel ! * in getImageTypes() when we have tRNS chunk for colorType ! * PNG_COLOR_RGB or PNG_COLOR_GRAY. ! */ ! boolean tRNSTransparentPixelPresent = ! theImage.getSampleModel().getNumBands() == inputBands + 1 && ! metadata.tRNS_present && ! (metadata.tRNS_colorType == PNG_COLOR_RGB || ! metadata.tRNS_colorType == PNG_COLOR_GRAY); ! if (useSetRect && ! !tRNSTransparentPixelPresent) ! { imRas.setRect(updateMinX, dstY, passRow); } else { int newSrcX = srcX; for (int dstX = updateMinX;
*** 1279,1289 **** --- 1307,1357 ---- if (adjustBitDepths) { for (int b = 0; b < numBands; b++) { ps[b] = scale[b][ps[b]]; } } + if (tRNSTransparentPixelPresent) + { + /* + * Create intermediate array to fill the extra + * alpha channel for each pixel. + */ + int[] temp = new int[inputBands + 1]; + if (metadata.tRNS_colorType == PNG_COLOR_RGB) { + temp[0] = ps[0]; + temp[1] = ps[1]; + temp[2] = ps[2]; + if (ps[0] == metadata.tRNS_red && + ps[1] == metadata.tRNS_green && + ps[2] == metadata.tRNS_blue) + { + temp[3] = 0; + } else { + if (bitDepth < 16) { + temp[3] = 255; + } else { + temp[3] = 65535; + } + } + } else { + // when tRNS_colorType is PNG_COLOR_GRAY + temp[0] = ps[0]; + if (ps[0] == metadata.tRNS_gray) + { + temp[1] = 0; + } else { + if (bitDepth < 16) { + temp[1] = 255; + } else { + temp[1] = 65535; + } + } + } + imRas.setPixel(dstX, dstY, temp); + } else { imRas.setPixel(dstX, dstY, ps); + } newSrcX += srcXStep; } } processImageUpdate(theImage,
*** 1420,1432 **** --- 1488,1511 ---- // At this point the header has been read and we know // how many bands are in the image, so perform checking // of the read param. int colorType = metadata.IHDR_colorType; + if (theImage.getSampleModel().getNumBands() == + inputBandsForColorType[colorType] + 1 && + metadata.tRNS_present && + (metadata.tRNS_colorType == PNG_COLOR_RGB || + metadata.tRNS_colorType == PNG_COLOR_GRAY)) + { + checkReadParamBandSettings(param, + inputBandsForColorType[colorType] + 1, + theImage.getSampleModel().getNumBands()); + } else { checkReadParamBandSettings(param, inputBandsForColorType[colorType], theImage.getSampleModel().getNumBands()); + } clearAbortRequest(); processImageStarted(0); if (abortRequested()) { processReadAborted();
*** 1504,1522 **** --- 1583,1629 ---- } else { dataType = DataBuffer.TYPE_USHORT; } switch (colorType) { + /* + * In case of PNG_COLOR_RGB or PNG_COLOR_GRAY, if we + * have transparent pixel information in tRNS chunk + * we create destination image having alpha channel. + */ case PNG_COLOR_GRAY: + readMetadata(); // Need tRNS chunk + + if (metadata.tRNS_present && + metadata.tRNS_colorType == PNG_COLOR_GRAY) + { + gray = ColorSpace.getInstance(ColorSpace.CS_GRAY); + bandOffsets = new int[2]; + bandOffsets[0] = 0; + bandOffsets[1] = 1; + l.add(ImageTypeSpecifier.createInterleaved(gray, + bandOffsets, + dataType, + true, + false)); + } // Packed grayscale l.add(ImageTypeSpecifier.createGrayscale(bitDepth, dataType, false)); break; case PNG_COLOR_RGB: + readMetadata(); // Need tRNS chunk + if (bitDepth == 8) { + if (metadata.tRNS_present && + metadata.tRNS_colorType == PNG_COLOR_RGB) + { + l.add(ImageTypeSpecifier.createFromBufferedImageType( + BufferedImage.TYPE_4BYTE_ABGR)); + } // some standard types of buffered images // which can be used as destination l.add(ImageTypeSpecifier.createFromBufferedImageType( BufferedImage.TYPE_3BYTE_BGR));
*** 1525,1534 **** --- 1632,1655 ---- l.add(ImageTypeSpecifier.createFromBufferedImageType( BufferedImage.TYPE_INT_BGR)); } + if (metadata.tRNS_present && + metadata.tRNS_colorType == PNG_COLOR_RGB) + { + rgb = ColorSpace.getInstance(ColorSpace.CS_sRGB); + bandOffsets = new int[4]; + bandOffsets[0] = 0; + bandOffsets[1] = 1; + bandOffsets[2] = 2; + bandOffsets[3] = 3; + + l.add(ImageTypeSpecifier. + createInterleaved(rgb, bandOffsets, + dataType, true, false)); + } // Component R, G, B rgb = ColorSpace.getInstance(ColorSpace.CS_sRGB); bandOffsets = new int[3]; bandOffsets[0] = 0; bandOffsets[1] = 1;
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