diff options
| author | Noel Grandin <noel.grandin@collabora.co.uk> | 2022-05-14 11:42:28 +0200 |
|---|---|---|
| committer | Noel Grandin <noel.grandin@collabora.co.uk> | 2022-05-16 08:08:09 +0200 |
| commit | 2fe18c214be06065a2966ffa3d4af5db6606b7ae (patch) | |
| tree | e8591fde99b6c665728a75e23a613a0f0249ee00 | |
| parent | fc2716740bd513154ae4ab5404d9c575678172e0 (diff) | |
optimise common case of reading a single-pass PNG
Change-Id: I5408f9d9b7c3e0d08c1bc6bafaca97f18898387f
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/134342
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
| -rw-r--r-- | vcl/source/filter/png/PngImageReader.cxx | 36 |
1 files changed, 29 insertions, 7 deletions
diff --git a/vcl/source/filter/png/PngImageReader.cxx b/vcl/source/filter/png/PngImageReader.cxx index 70ae63240227..6a3053a72e12 100644 --- a/vcl/source/filter/png/PngImageReader.cxx +++ b/vcl/source/filter/png/PngImageReader.cxx @@ -100,7 +100,6 @@ bool reader(SvStream& rStream, BitmapEx& rBitmapEx, Size prefSize; BitmapScopedWriteAccess pWriteAccessInstance; AlphaScopedWriteAccess pWriteAccessAlphaInstance; - std::vector<std::vector<png_byte>> aRows; const bool bFuzzing = utl::ConfigManager::IsFuzzing(); const bool bSupportsBitmap32 = bFuzzing || ImplGetSVData()->mpDefInst->supportsBitmap32(); const bool bOnlyCreateBitmap @@ -342,17 +341,15 @@ bool reader(SvStream& rStream, BitmapEx& rBitmapEx, if (eFormat == ScanlineFormat::N24BitTcBgr) png_set_bgr(pPng); - aRows = std::vector<std::vector<png_byte>>(height); - for (auto& rRow : aRows) - rRow.resize(aRowSizeBytes, 0); - - for (int pass = 0; pass < nNumberOfPasses; pass++) + if (nNumberOfPasses == 1) { + // optimise the common case, where we can use a buffer of only a single row + std::vector<png_byte> aRow(aRowSizeBytes, 0); for (png_uint_32 y = 0; y < height; y++) { Scanline pScanline = pWriteAccess->GetScanline(y); Scanline pScanAlpha = pWriteAccessAlpha->GetScanline(y); - png_bytep pRow = aRows[y].data(); + png_bytep pRow = aRow.data(); png_read_row(pPng, pRow, nullptr); size_t iAlpha = 0; size_t iColor = 0; @@ -365,6 +362,31 @@ bool reader(SvStream& rStream, BitmapEx& rBitmapEx, } } } + else + { + std::vector<std::vector<png_byte>> aRows(height); + for (auto& rRow : aRows) + rRow.resize(aRowSizeBytes, 0); + for (int pass = 0; pass < nNumberOfPasses; pass++) + { + for (png_uint_32 y = 0; y < height; y++) + { + Scanline pScanline = pWriteAccess->GetScanline(y); + Scanline pScanAlpha = pWriteAccessAlpha->GetScanline(y); + png_bytep pRow = aRows[y].data(); + png_read_row(pPng, pRow, nullptr); + size_t iAlpha = 0; + size_t iColor = 0; + for (size_t i = 0; i < aRowSizeBytes; i += 4) + { + pScanline[iColor++] = pRow[i + 0]; + pScanline[iColor++] = pRow[i + 1]; + pScanline[iColor++] = pRow[i + 2]; + pScanAlpha[iAlpha++] = 0xFF - pRow[i + 3]; + } + } + } + } } } else if (colorType == PNG_COLOR_TYPE_GRAY) |