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755 lines
28 KiB
C++
755 lines
28 KiB
C++
/* vim:set tw=80 expandtab softtabstop=4 ts=4 sw=4: */
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/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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/* I got the format description from http://www.daubnet.com/formats/BMP.html */
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/* This is a Cross-Platform BMP Decoder, which should work everywhere, including
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* Big-Endian machines like the PowerPC. */
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#include <stdlib.h>
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#include "ImageLogging.h"
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#include "EndianMacros.h"
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#include "nsBMPDecoder.h"
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#include "nsIInputStream.h"
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#include "RasterImage.h"
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#include <algorithm>
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namespace mozilla {
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namespace image {
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#ifdef PR_LOGGING
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static PRLogModuleInfo *
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GetBMPLog()
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{
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static PRLogModuleInfo *sBMPLog;
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if (!sBMPLog)
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sBMPLog = PR_NewLogModule("BMPDecoder");
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return sBMPLog;
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}
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#endif
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// Convert from row (1..height) to absolute line (0..height-1)
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#define LINE(row) ((mBIH.height < 0) ? (-mBIH.height - (row)) : ((row) - 1))
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#define PIXEL_OFFSET(row, col) (LINE(row) * mBIH.width + col)
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nsBMPDecoder::nsBMPDecoder(RasterImage &aImage, imgDecoderObserver* aObserver)
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: Decoder(aImage, aObserver)
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{
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mColors = nullptr;
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mRow = nullptr;
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mImageData = nullptr;
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mCurPos = mPos = mNumColors = mRowBytes = 0;
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mOldLine = mCurLine = 1; // Otherwise decoder will never start
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mState = eRLEStateInitial;
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mStateData = 0;
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mLOH = WIN_V3_HEADER_LENGTH;
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mUseAlphaData = mHaveAlphaData = false;
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}
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nsBMPDecoder::~nsBMPDecoder()
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{
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delete[] mColors;
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if (mRow) {
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moz_free(mRow);
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}
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}
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// Sets whether or not the BMP will use alpha data
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void
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nsBMPDecoder::SetUseAlphaData(bool useAlphaData)
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{
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mUseAlphaData = useAlphaData;
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}
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// Obtains the bits per pixel from the internal BIH header
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int32_t
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nsBMPDecoder::GetBitsPerPixel() const
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{
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return mBIH.bpp;
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}
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// Obtains the width from the internal BIH header
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int32_t
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nsBMPDecoder::GetWidth() const
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{
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return mBIH.width;
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}
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// Obtains the abs-value of the height from the internal BIH header
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int32_t
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nsBMPDecoder::GetHeight() const
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{
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return abs(mBIH.height);
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}
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// Obtains the internal output image buffer
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uint32_t*
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nsBMPDecoder::GetImageData()
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{
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return mImageData;
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}
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// Obtains the size of the compressed image resource
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int32_t
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nsBMPDecoder::GetCompressedImageSize() const
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{
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// For everything except BI_RGB the header field must be defined
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if (mBIH.compression != BI_RGB) {
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return mBIH.image_size;
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}
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// mBIH.image_size isn't always filled for BI_RGB so calculate it manually
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// The pixel array size is calculated based on extra 4 byte boundary padding
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uint32_t rowSize = (mBIH.bpp * mBIH.width + 7) / 8; // + 7 to round up
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// Pad to DWORD Boundary
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if (rowSize % 4) {
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rowSize += (4 - (rowSize % 4));
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}
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// The height should be the absolute value of what the height is in the BIH.
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// If positive the bitmap is stored bottom to top, otherwise top to bottom
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int32_t pixelArraySize = rowSize * GetHeight();
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return pixelArraySize;
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}
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// Obtains whether or not a BMP file had alpha data in its 4th byte
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// for 32BPP bitmaps. Only use after the bitmap has been processed.
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bool
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nsBMPDecoder::HasAlphaData() const
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{
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return mHaveAlphaData;
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}
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void
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nsBMPDecoder::FinishInternal()
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{
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// We shouldn't be called in error cases
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NS_ABORT_IF_FALSE(!HasError(), "Can't call FinishInternal on error!");
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// We should never make multiple frames
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NS_ABORT_IF_FALSE(GetFrameCount() <= 1, "Multiple BMP frames?");
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// Send notifications if appropriate
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if (!IsSizeDecode() && (GetFrameCount() == 1)) {
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// Invalidate
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nsIntRect r(0, 0, mBIH.width, GetHeight());
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PostInvalidation(r);
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PostFrameStop();
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PostDecodeDone();
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}
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}
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// ----------------------------------------
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// Actual Data Processing
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// ----------------------------------------
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static void calcBitmask(uint32_t aMask, uint8_t& aBegin, uint8_t& aLength)
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{
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// find the rightmost 1
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uint8_t pos;
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bool started = false;
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aBegin = aLength = 0;
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for (pos = 0; pos <= 31; pos++) {
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if (!started && (aMask & (1 << pos))) {
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aBegin = pos;
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started = true;
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}
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else if (started && !(aMask & (1 << pos))) {
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aLength = pos - aBegin;
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break;
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}
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}
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}
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NS_METHOD nsBMPDecoder::CalcBitShift()
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{
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uint8_t begin, length;
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// red
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calcBitmask(mBitFields.red, begin, length);
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mBitFields.redRightShift = begin;
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mBitFields.redLeftShift = 8 - length;
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// green
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calcBitmask(mBitFields.green, begin, length);
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mBitFields.greenRightShift = begin;
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mBitFields.greenLeftShift = 8 - length;
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// blue
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calcBitmask(mBitFields.blue, begin, length);
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mBitFields.blueRightShift = begin;
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mBitFields.blueLeftShift = 8 - length;
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return NS_OK;
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}
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void
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nsBMPDecoder::WriteInternal(const char* aBuffer, uint32_t aCount)
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{
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NS_ABORT_IF_FALSE(!HasError(), "Shouldn't call WriteInternal after error!");
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// aCount=0 means EOF, mCurLine=0 means we're past end of image
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if (!aCount || !mCurLine)
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return;
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nsresult rv;
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if (mPos < BFH_INTERNAL_LENGTH) { /* In BITMAPFILEHEADER */
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uint32_t toCopy = BFH_INTERNAL_LENGTH - mPos;
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if (toCopy > aCount)
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toCopy = aCount;
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memcpy(mRawBuf + mPos, aBuffer, toCopy);
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mPos += toCopy;
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aCount -= toCopy;
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aBuffer += toCopy;
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}
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if (mPos == BFH_INTERNAL_LENGTH) {
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ProcessFileHeader();
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if (mBFH.signature[0] != 'B' || mBFH.signature[1] != 'M') {
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PostDataError();
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return;
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}
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if (mBFH.bihsize == OS2_BIH_LENGTH)
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mLOH = OS2_HEADER_LENGTH;
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}
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if (mPos >= BFH_INTERNAL_LENGTH && mPos < mLOH) { /* In BITMAPINFOHEADER */
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uint32_t toCopy = mLOH - mPos;
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if (toCopy > aCount)
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toCopy = aCount;
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memcpy(mRawBuf + (mPos - BFH_INTERNAL_LENGTH), aBuffer, toCopy);
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mPos += toCopy;
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aCount -= toCopy;
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aBuffer += toCopy;
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}
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// GetNumFrames is called to ensure that if at this point mPos == mLOH but
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// we have no data left to process, the next time WriteInternal is called
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// we won't enter this condition again.
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if (mPos == mLOH && GetFrameCount() == 0) {
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ProcessInfoHeader();
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PR_LOG(GetBMPLog(), PR_LOG_DEBUG, ("BMP is %lix%lix%lu. compression=%lu\n",
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mBIH.width, mBIH.height, mBIH.bpp, mBIH.compression));
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// Verify we support this bit depth
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if (mBIH.bpp != 1 && mBIH.bpp != 4 && mBIH.bpp != 8 &&
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mBIH.bpp != 16 && mBIH.bpp != 24 && mBIH.bpp != 32) {
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PostDataError();
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return;
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}
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// BMPs with negative width are invalid
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// Reject extremely wide images to keep the math sane
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const int32_t k64KWidth = 0x0000FFFF;
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if (mBIH.width < 0 || mBIH.width > k64KWidth) {
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PostDataError();
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return;
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}
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uint32_t real_height = GetHeight();
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// Post our size to the superclass
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PostSize(mBIH.width, real_height);
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if (HasError()) {
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// Setting the size led to an error.
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return;
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}
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// We have the size. If we're doing a size decode, we got what
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// we came for.
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if (IsSizeDecode())
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return;
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// We're doing a real decode.
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mOldLine = mCurLine = real_height;
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if (mBIH.bpp <= 8) {
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mNumColors = 1 << mBIH.bpp;
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if (mBIH.colors && mBIH.colors < mNumColors)
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mNumColors = mBIH.colors;
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// Always allocate 256 even though mNumColors might be smaller
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mColors = new colorTable[256];
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memset(mColors, 0, 256 * sizeof(colorTable));
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}
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else if (mBIH.compression != BI_BITFIELDS && mBIH.bpp == 16) {
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// Use default 5-5-5 format
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mBitFields.red = 0x7C00;
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mBitFields.green = 0x03E0;
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mBitFields.blue = 0x001F;
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CalcBitShift();
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}
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// Make sure we have a valid value for our supported compression modes
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// before adding the frame
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if (mBIH.compression != BI_RGB && mBIH.compression != BI_RLE8 &&
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mBIH.compression != BI_RLE4 && mBIH.compression != BI_BITFIELDS) {
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PostDataError();
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return;
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}
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// If we have RLE4 or RLE8 or BI_ALPHABITFIELDS, then ensure we
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// have valid BPP values before adding the frame
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if (mBIH.compression == BI_RLE8 && mBIH.bpp != 8) {
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PR_LOG(GetBMPLog(), PR_LOG_DEBUG,
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("BMP RLE8 compression only supports 8 bits per pixel\n"));
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PostDataError();
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return;
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}
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if (mBIH.compression == BI_RLE4 && mBIH.bpp != 4 && mBIH.bpp != 1) {
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PR_LOG(GetBMPLog(), PR_LOG_DEBUG,
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("BMP RLE4 compression only supports 4 bits per pixel\n"));
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PostDataError();
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return;
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}
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if (mBIH.compression == BI_ALPHABITFIELDS &&
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mBIH.bpp != 16 && mBIH.bpp != 32) {
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PR_LOG(GetBMPLog(), PR_LOG_DEBUG,
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("BMP ALPHABITFIELDS only supports 16 or 32 bits per pixel\n"));
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PostDataError();
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return;
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}
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uint32_t imageLength;
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if (mBIH.compression == BI_RLE8 || mBIH.compression == BI_RLE4 ||
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mBIH.compression == BI_ALPHABITFIELDS) {
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rv = mImage.EnsureFrame(0, 0, 0, mBIH.width, real_height,
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gfxASurface::ImageFormatARGB32,
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(uint8_t**)&mImageData, &imageLength);
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} else {
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// mRow is not used for RLE encoded images
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mRow = (uint8_t*)moz_malloc((mBIH.width * mBIH.bpp) / 8 + 4);
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// + 4 because the line is padded to a 4 bit boundary, but I don't want
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// to make exact calculations here, that's unnecessary.
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// Also, it compensates rounding error.
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if (!mRow) {
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PostDecoderError(NS_ERROR_OUT_OF_MEMORY);
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return;
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}
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if (mUseAlphaData) {
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rv = mImage.EnsureFrame(0, 0, 0, mBIH.width, real_height,
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gfxASurface::ImageFormatARGB32,
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(uint8_t**)&mImageData, &imageLength);
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} else {
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rv = mImage.EnsureFrame(0, 0, 0, mBIH.width, real_height,
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gfxASurface::ImageFormatRGB24,
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(uint8_t**)&mImageData, &imageLength);
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}
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}
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if (NS_FAILED(rv) || !mImageData) {
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PostDecoderError(NS_ERROR_FAILURE);
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return;
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}
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// Prepare for transparency
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if ((mBIH.compression == BI_RLE8) || (mBIH.compression == BI_RLE4)) {
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// Clear the image, as the RLE may jump over areas
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memset(mImageData, 0, imageLength);
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}
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// Tell the superclass we're starting a frame
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PostFrameStart();
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}
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if (mColors && mPos >= mLOH) {
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// OS/2 Bitmaps have no padding byte
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uint8_t bytesPerColor = (mBFH.bihsize == OS2_BIH_LENGTH) ? 3 : 4;
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if (mPos < (mLOH + mNumColors * bytesPerColor)) {
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// Number of bytes already received
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uint32_t colorBytes = mPos - mLOH;
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// Color which is currently received
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uint8_t colorNum = colorBytes / bytesPerColor;
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uint8_t at = colorBytes % bytesPerColor;
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while (aCount && (mPos < (mLOH + mNumColors * bytesPerColor))) {
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switch (at) {
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case 0:
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mColors[colorNum].blue = *aBuffer;
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break;
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case 1:
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mColors[colorNum].green = *aBuffer;
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break;
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case 2:
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mColors[colorNum].red = *aBuffer;
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// If there is no padding byte, increment the color index
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// since we're done with the current color.
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if (bytesPerColor == 3)
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colorNum++;
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break;
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case 3:
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// This is a padding byte only in Windows BMPs. Increment
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// the color index since we're done with the current color.
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colorNum++;
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break;
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}
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mPos++; aBuffer++; aCount--;
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at = (at + 1) % bytesPerColor;
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}
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}
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}
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else if (aCount && mBIH.compression == BI_BITFIELDS && mPos < (WIN_V3_HEADER_LENGTH + BITFIELD_LENGTH)) {
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// If compression is used, this is a windows bitmap, hence we can
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// use WIN_HEADER_LENGTH instead of mLOH
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uint32_t toCopy = (WIN_V3_HEADER_LENGTH + BITFIELD_LENGTH) - mPos;
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if (toCopy > aCount)
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toCopy = aCount;
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memcpy(mRawBuf + (mPos - WIN_V3_HEADER_LENGTH), aBuffer, toCopy);
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mPos += toCopy;
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aBuffer += toCopy;
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aCount -= toCopy;
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}
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if (mPos == WIN_V3_HEADER_LENGTH + BITFIELD_LENGTH &&
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mBIH.compression == BI_BITFIELDS) {
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mBitFields.red = LITTLE_TO_NATIVE32(*(uint32_t*)mRawBuf);
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mBitFields.green = LITTLE_TO_NATIVE32(*(uint32_t*)(mRawBuf + 4));
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mBitFields.blue = LITTLE_TO_NATIVE32(*(uint32_t*)(mRawBuf + 8));
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CalcBitShift();
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}
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while (aCount && (mPos < mBFH.dataoffset)) { // Skip whatever is between header and data
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mPos++; aBuffer++; aCount--;
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}
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if (aCount && ++mPos >= mBFH.dataoffset) {
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// Need to increment mPos, else we might get to mPos==mLOH again
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// From now on, mPos is irrelevant
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if (!mBIH.compression || mBIH.compression == BI_BITFIELDS) {
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uint32_t rowSize = (mBIH.bpp * mBIH.width + 7) / 8; // + 7 to round up
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if (rowSize % 4) {
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rowSize += (4 - (rowSize % 4)); // Pad to DWORD Boundary
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}
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uint32_t toCopy;
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do {
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toCopy = rowSize - mRowBytes;
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if (toCopy) {
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if (toCopy > aCount)
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toCopy = aCount;
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memcpy(mRow + mRowBytes, aBuffer, toCopy);
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aCount -= toCopy;
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aBuffer += toCopy;
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mRowBytes += toCopy;
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}
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if (rowSize == mRowBytes) {
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// Collected a whole row into mRow, process it
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uint8_t* p = mRow;
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uint32_t* d = mImageData + PIXEL_OFFSET(mCurLine, 0);
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uint32_t lpos = mBIH.width;
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switch (mBIH.bpp) {
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case 1:
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while (lpos > 0) {
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int8_t bit;
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uint8_t idx;
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for (bit = 7; bit >= 0 && lpos > 0; bit--) {
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idx = (*p >> bit) & 1;
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SetPixel(d, idx, mColors);
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--lpos;
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}
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++p;
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}
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break;
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case 4:
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while (lpos > 0) {
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Set4BitPixel(d, *p, lpos, mColors);
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++p;
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}
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break;
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case 8:
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while (lpos > 0) {
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SetPixel(d, *p, mColors);
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--lpos;
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++p;
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}
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break;
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case 16:
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while (lpos > 0) {
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uint16_t val = LITTLE_TO_NATIVE16(*(uint16_t*)p);
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SetPixel(d,
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(val & mBitFields.red) >> mBitFields.redRightShift << mBitFields.redLeftShift,
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(val & mBitFields.green) >> mBitFields.greenRightShift << mBitFields.greenLeftShift,
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(val & mBitFields.blue) >> mBitFields.blueRightShift << mBitFields.blueLeftShift);
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--lpos;
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p+=2;
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}
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break;
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case 24:
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while (lpos > 0) {
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SetPixel(d, p[2], p[1], p[0]);
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p += 2;
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--lpos;
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++p;
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}
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break;
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case 32:
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while (lpos > 0) {
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if (mUseAlphaData) {
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if (!mHaveAlphaData && p[3]) {
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// Non-zero alpha byte detected! Clear previous
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// pixels that we have already processed.
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// This works because we know that if we
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// are reaching here then the alpha data in byte
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// 4 has been right all along. And we know it
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// has been set to 0 the whole time, so that
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// means that everything is transparent so far.
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|
uint32_t* start = mImageData + GetWidth() * (mCurLine - 1);
|
|
uint32_t heightDifference = GetHeight() - mCurLine + 1;
|
|
uint32_t pixelCount = GetWidth() * heightDifference;
|
|
|
|
memset(start, 0, pixelCount * sizeof(uint32_t));
|
|
|
|
mHaveAlphaData = true;
|
|
}
|
|
SetPixel(d, p[2], p[1], p[0], mHaveAlphaData ? p[3] : 0xFF);
|
|
} else {
|
|
SetPixel(d, p[2], p[1], p[0]);
|
|
}
|
|
p += 4;
|
|
--lpos;
|
|
}
|
|
break;
|
|
default:
|
|
NS_NOTREACHED("Unsupported color depth, but earlier check didn't catch it");
|
|
}
|
|
mCurLine --;
|
|
if (mCurLine == 0) { // Finished last line
|
|
break;
|
|
}
|
|
mRowBytes = 0;
|
|
|
|
}
|
|
} while (aCount > 0);
|
|
}
|
|
else if ((mBIH.compression == BI_RLE8) || (mBIH.compression == BI_RLE4)) {
|
|
if (((mBIH.compression == BI_RLE8) && (mBIH.bpp != 8)) ||
|
|
((mBIH.compression == BI_RLE4) && (mBIH.bpp != 4) && (mBIH.bpp != 1))) {
|
|
PR_LOG(GetBMPLog(), PR_LOG_DEBUG, ("BMP RLE8/RLE4 compression only supports 8/4 bits per pixel\n"));
|
|
PostDataError();
|
|
return;
|
|
}
|
|
|
|
while (aCount > 0) {
|
|
uint8_t byte;
|
|
|
|
switch(mState) {
|
|
case eRLEStateInitial:
|
|
mStateData = (uint8_t)*aBuffer++;
|
|
aCount--;
|
|
|
|
mState = eRLEStateNeedSecondEscapeByte;
|
|
continue;
|
|
|
|
case eRLEStateNeedSecondEscapeByte:
|
|
byte = *aBuffer++;
|
|
aCount--;
|
|
if (mStateData != RLE_ESCAPE) { // encoded mode
|
|
// Encoded mode consists of two bytes:
|
|
// the first byte (mStateData) specifies the
|
|
// number of consecutive pixels to be drawn
|
|
// using the color index contained in
|
|
// the second byte
|
|
// Work around bitmaps that specify too many pixels
|
|
mState = eRLEStateInitial;
|
|
uint32_t pixelsNeeded = std::min<uint32_t>(mBIH.width - mCurPos, mStateData);
|
|
if (pixelsNeeded) {
|
|
uint32_t* d = mImageData + PIXEL_OFFSET(mCurLine, mCurPos);
|
|
mCurPos += pixelsNeeded;
|
|
if (mBIH.compression == BI_RLE8) {
|
|
do {
|
|
SetPixel(d, byte, mColors);
|
|
pixelsNeeded --;
|
|
} while (pixelsNeeded);
|
|
} else {
|
|
do {
|
|
Set4BitPixel(d, byte, pixelsNeeded, mColors);
|
|
} while (pixelsNeeded);
|
|
}
|
|
}
|
|
continue;
|
|
}
|
|
|
|
switch(byte) {
|
|
case RLE_ESCAPE_EOL:
|
|
// End of Line: Go to next row
|
|
mCurLine --;
|
|
mCurPos = 0;
|
|
mState = eRLEStateInitial;
|
|
break;
|
|
|
|
case RLE_ESCAPE_EOF: // EndOfFile
|
|
mCurPos = mCurLine = 0;
|
|
break;
|
|
|
|
case RLE_ESCAPE_DELTA:
|
|
mState = eRLEStateNeedXDelta;
|
|
continue;
|
|
|
|
default : // absolute mode
|
|
// Save the number of pixels to read
|
|
mStateData = byte;
|
|
if (mCurPos + mStateData > (uint32_t)mBIH.width) {
|
|
// We can work around bitmaps that specify one
|
|
// pixel too many, but only if their width is odd.
|
|
mStateData -= mBIH.width & 1;
|
|
if (mCurPos + mStateData > (uint32_t)mBIH.width) {
|
|
PostDataError();
|
|
return;
|
|
}
|
|
}
|
|
|
|
// See if we will need to skip a byte
|
|
// to word align the pixel data
|
|
// mStateData is a number of pixels
|
|
// so allow for the RLE compression type
|
|
// Pixels RLE8=1 RLE4=2
|
|
// 1 Pad Pad
|
|
// 2 No Pad
|
|
// 3 Pad No
|
|
// 4 No No
|
|
if (((mStateData - 1) & mBIH.compression) != 0)
|
|
mState = eRLEStateAbsoluteMode;
|
|
else
|
|
mState = eRLEStateAbsoluteModePadded;
|
|
continue;
|
|
}
|
|
break;
|
|
|
|
case eRLEStateNeedXDelta:
|
|
// Handle the XDelta and proceed to get Y Delta
|
|
byte = *aBuffer++;
|
|
aCount--;
|
|
mCurPos += byte;
|
|
if (mCurPos > mBIH.width)
|
|
mCurPos = mBIH.width;
|
|
|
|
mState = eRLEStateNeedYDelta;
|
|
continue;
|
|
|
|
case eRLEStateNeedYDelta:
|
|
// Get the Y Delta and then "handle" the move
|
|
byte = *aBuffer++;
|
|
aCount--;
|
|
mState = eRLEStateInitial;
|
|
mCurLine -= std::min<int32_t>(byte, mCurLine);
|
|
break;
|
|
|
|
case eRLEStateAbsoluteMode: // Absolute Mode
|
|
case eRLEStateAbsoluteModePadded:
|
|
if (mStateData) {
|
|
// In absolute mode, the second byte (mStateData)
|
|
// represents the number of pixels
|
|
// that follow, each of which contains
|
|
// the color index of a single pixel.
|
|
uint32_t* d = mImageData + PIXEL_OFFSET(mCurLine, mCurPos);
|
|
uint32_t* oldPos = d;
|
|
if (mBIH.compression == BI_RLE8) {
|
|
while (aCount > 0 && mStateData > 0) {
|
|
byte = *aBuffer++;
|
|
aCount--;
|
|
SetPixel(d, byte, mColors);
|
|
mStateData--;
|
|
}
|
|
} else {
|
|
while (aCount > 0 && mStateData > 0) {
|
|
byte = *aBuffer++;
|
|
aCount--;
|
|
Set4BitPixel(d, byte, mStateData, mColors);
|
|
}
|
|
}
|
|
mCurPos += d - oldPos;
|
|
}
|
|
|
|
if (mStateData == 0) {
|
|
// In absolute mode, each run must
|
|
// be aligned on a word boundary
|
|
|
|
if (mState == eRLEStateAbsoluteMode) { // Word Aligned
|
|
mState = eRLEStateInitial;
|
|
} else if (aCount > 0) { // Not word Aligned
|
|
// "next" byte is just a padding byte
|
|
// so "move" past it and we can continue
|
|
aBuffer++;
|
|
aCount--;
|
|
mState = eRLEStateInitial;
|
|
}
|
|
}
|
|
// else state is still eRLEStateAbsoluteMode
|
|
continue;
|
|
|
|
default :
|
|
NS_ABORT_IF_FALSE(0, "BMP RLE decompression: unknown state!");
|
|
PostDecoderError(NS_ERROR_UNEXPECTED);
|
|
return;
|
|
}
|
|
// Because of the use of the continue statement
|
|
// we only get here for eol, eof or y delta
|
|
if (mCurLine == 0) { // Finished last line
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
const uint32_t rows = mOldLine - mCurLine;
|
|
if (rows) {
|
|
|
|
// Invalidate
|
|
nsIntRect r(0, mBIH.height < 0 ? -mBIH.height - mOldLine : mCurLine,
|
|
mBIH.width, rows);
|
|
PostInvalidation(r);
|
|
|
|
mOldLine = mCurLine;
|
|
}
|
|
|
|
return;
|
|
}
|
|
|
|
void nsBMPDecoder::ProcessFileHeader()
|
|
{
|
|
memset(&mBFH, 0, sizeof(mBFH));
|
|
memcpy(&mBFH.signature, mRawBuf, sizeof(mBFH.signature));
|
|
memcpy(&mBFH.filesize, mRawBuf + 2, sizeof(mBFH.filesize));
|
|
memcpy(&mBFH.reserved, mRawBuf + 6, sizeof(mBFH.reserved));
|
|
memcpy(&mBFH.dataoffset, mRawBuf + 10, sizeof(mBFH.dataoffset));
|
|
memcpy(&mBFH.bihsize, mRawBuf + 14, sizeof(mBFH.bihsize));
|
|
|
|
// Now correct the endianness of the header
|
|
mBFH.filesize = LITTLE_TO_NATIVE32(mBFH.filesize);
|
|
mBFH.dataoffset = LITTLE_TO_NATIVE32(mBFH.dataoffset);
|
|
mBFH.bihsize = LITTLE_TO_NATIVE32(mBFH.bihsize);
|
|
}
|
|
|
|
void nsBMPDecoder::ProcessInfoHeader()
|
|
{
|
|
memset(&mBIH, 0, sizeof(mBIH));
|
|
if (mBFH.bihsize == 12) { // OS/2 Bitmap
|
|
memcpy(&mBIH.width, mRawBuf, 2);
|
|
memcpy(&mBIH.height, mRawBuf + 2, 2);
|
|
memcpy(&mBIH.planes, mRawBuf + 4, sizeof(mBIH.planes));
|
|
memcpy(&mBIH.bpp, mRawBuf + 6, sizeof(mBIH.bpp));
|
|
}
|
|
else {
|
|
memcpy(&mBIH.width, mRawBuf, sizeof(mBIH.width));
|
|
memcpy(&mBIH.height, mRawBuf + 4, sizeof(mBIH.height));
|
|
memcpy(&mBIH.planes, mRawBuf + 8, sizeof(mBIH.planes));
|
|
memcpy(&mBIH.bpp, mRawBuf + 10, sizeof(mBIH.bpp));
|
|
memcpy(&mBIH.compression, mRawBuf + 12, sizeof(mBIH.compression));
|
|
memcpy(&mBIH.image_size, mRawBuf + 16, sizeof(mBIH.image_size));
|
|
memcpy(&mBIH.xppm, mRawBuf + 20, sizeof(mBIH.xppm));
|
|
memcpy(&mBIH.yppm, mRawBuf + 24, sizeof(mBIH.yppm));
|
|
memcpy(&mBIH.colors, mRawBuf + 28, sizeof(mBIH.colors));
|
|
memcpy(&mBIH.important_colors, mRawBuf + 32, sizeof(mBIH.important_colors));
|
|
}
|
|
|
|
// Convert endianness
|
|
mBIH.width = LITTLE_TO_NATIVE32(mBIH.width);
|
|
mBIH.height = LITTLE_TO_NATIVE32(mBIH.height);
|
|
mBIH.planes = LITTLE_TO_NATIVE16(mBIH.planes);
|
|
mBIH.bpp = LITTLE_TO_NATIVE16(mBIH.bpp);
|
|
|
|
mBIH.compression = LITTLE_TO_NATIVE32(mBIH.compression);
|
|
mBIH.image_size = LITTLE_TO_NATIVE32(mBIH.image_size);
|
|
mBIH.xppm = LITTLE_TO_NATIVE32(mBIH.xppm);
|
|
mBIH.yppm = LITTLE_TO_NATIVE32(mBIH.yppm);
|
|
mBIH.colors = LITTLE_TO_NATIVE32(mBIH.colors);
|
|
mBIH.important_colors = LITTLE_TO_NATIVE32(mBIH.important_colors);
|
|
}
|
|
|
|
} // namespace image
|
|
} // namespace mozilla
|