gfx/2d/Scale.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "Scale.h"
   8
   9 #ifdef USE_SKIA
  10 #  include "HelpersSkia.h"
  11 #  include "skia/src/core/SkBitmapScaler.h"
  12 #endif
  13
  14 namespace mozilla {
  15 namespace gfx {
  16
  17 bool Scale(uint8_t* srcData, int32_t srcWidth, int32_t srcHeight,
  18            int32_t srcStride, uint8_t* dstData, int32_t dstWidth,
  19            int32_t dstHeight, int32_t dstStride, SurfaceFormat format) {
  20 #ifdef USE_SKIA
  21   SkPixmap srcPixmap(MakeSkiaImageInfo(IntSize(srcWidth, srcHeight), format),
  22                      srcData, srcStride);
  23
  24   // Rescaler is compatible with N32 only. Convert to N32 if needed.
  25   SkBitmap tmpBitmap;
  26   if (srcPixmap.colorType() != kN32_SkColorType) {
  27     if (!tmpBitmap.tryAllocPixels(
  28             SkImageInfo::MakeN32Premul(srcWidth, srcHeight)) ||
  29         !tmpBitmap.writePixels(srcPixmap) ||
  30         !tmpBitmap.peekPixels(&srcPixmap)) {
  31       return false;
  32     }
  33   }
  34
  35   SkPixmap dstPixmap(SkImageInfo::MakeN32Premul(dstWidth, dstHeight), dstData,
  36                      dstStride);
  37   return SkBitmapScaler::Resize(dstPixmap, srcPixmap,
  38                                 SkBitmapScaler::RESIZE_LANCZOS3);
  39 #else
  40   return false;
  41 #endif
  42 }
  43
  44 }  // namespace gfx
  45 }  // namespace mozilla