src/third_party/WebKit/Source/platform/image-encoders/skia/WEBPImageEncoder.cpp

   1 /*
   2  * Copyright (c) 2011, Google Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions are
   6  * met:
   7  *
   8  *     * Redistributions of source code must retain the above copyright
   9  * notice, this list of conditions and the following disclaimer.
  10  *     * Redistributions in binary form must reproduce the above
  11  * copyright notice, this list of conditions and the following disclaimer
  12  * in the documentation and/or other materials provided with the
  13  * distribution.
  14  *     * Neither the name of Google Inc. nor the names of its
  15  * contributors may be used to endorse or promote products derived from
  16  * this software without specific prior written permission.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  22  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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  24  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include "config.h"
  32 #include "platform/image-encoders/skia/WEBPImageEncoder.h"
  33
  34 #include "SkBitmap.h"
  35 #include "platform/geometry/IntSize.h"
  36 #include "platform/graphics/ImageBuffer.h"
  37 #include "webp/encode.h"
  38
  39 typedef int (*WebPImporter)(WebPPicture* const, const uint8_t* const data, int rowStride);
  40
  41 namespace blink {
  42
  43 static int writeOutput(const uint8_t* data, size_t size, const WebPPicture* const picture)
  44 {
  45     static_cast<Vector<unsigned char>*>(picture->custom_ptr)->append(data, size);
  46     return 1;
  47 }
  48
  49 static bool rgbPictureImport(const unsigned char* pixels, bool premultiplied, WebPImporter importRGBX, WebPImporter importRGB, WebPPicture* picture)
  50 {
  51     if (premultiplied)
  52         return importRGBX(picture, pixels, picture->width * 4);
  53
  54     // Write the RGB pixels to an rgb data buffer, alpha premultiplied, then import the rgb data.
  55
  56     Vector<unsigned char> rgb;
  57     size_t pixelCount = picture->height * picture->width;
  58     rgb.reserveInitialCapacity(pixelCount * 3);
  59
  60     for (unsigned char* data = rgb.data(); pixelCount-- > 0; pixels += 4) {
  61         unsigned char alpha = pixels[3];
  62         if (alpha != 255) {
  63             *data++ = SkMulDiv255Round(pixels[0], alpha);
  64             *data++ = SkMulDiv255Round(pixels[1], alpha);
  65             *data++ = SkMulDiv255Round(pixels[2], alpha);
  66         } else {
  67             *data++ = pixels[0];
  68             *data++ = pixels[1];
  69             *data++ = pixels[2];
  70         }
  71     }
  72
  73     return importRGB(picture, rgb.data(), picture->width * 3);
  74 }
  75
  76 template <bool Premultiplied> inline bool importPictureBGRX(const unsigned char* pixels, WebPPicture* picture)
  77 {
  78     return rgbPictureImport(pixels, Premultiplied, &WebPPictureImportBGRX, &WebPPictureImportBGR, picture);
  79 }
  80
  81 template <bool Premultiplied> inline bool importPictureRGBX(const unsigned char* pixels, WebPPicture* picture)
  82 {
  83     return rgbPictureImport(pixels, Premultiplied, &WebPPictureImportRGBX, &WebPPictureImportRGB, picture);
  84 }
  85
  86 static bool platformPremultipliedImportPicture(const unsigned char* pixels, WebPPicture* picture)
  87 {
  88     if (SK_B32_SHIFT) // Android
  89         return importPictureRGBX<true>(pixels, picture);
  90
  91     return importPictureBGRX<true>(pixels, picture);
  92 }
  93
  94 static bool encodePixels(IntSize imageSize, const unsigned char* pixels, bool premultiplied, int quality, Vector<unsigned char>* output)
  95 {
  96     WebPConfig config;
  97     if (!WebPConfigInit(&config))
  98         return false;
  99     WebPPicture picture;
 100     if (!WebPPictureInit(&picture))
 101         return false;
 102
 103     imageSize.clampNegativeToZero();
 104     if (!imageSize.width() || imageSize.width() > WEBP_MAX_DIMENSION)
 105         return false;
 106     picture.width = imageSize.width();
 107     if (!imageSize.height() || imageSize.height() > WEBP_MAX_DIMENSION)
 108         return false;
 109     picture.height = imageSize.height();
 110
 111     if (premultiplied && !platformPremultipliedImportPicture(pixels, &picture))
 112         return false;
 113     if (!premultiplied && !importPictureRGBX<false>(pixels, &picture))
 114         return false;
 115
 116     picture.custom_ptr = output;
 117     picture.writer = &writeOutput;
 118     config.quality = quality;
 119     config.method = 3;
 120
 121     bool success = WebPEncode(&config, &picture);
 122     WebPPictureFree(&picture);
 123     return success;
 124 }
 125
 126 bool WEBPImageEncoder::encode(const SkBitmap& bitmap, int quality, Vector<unsigned char>* output)
 127 {
 128     SkAutoLockPixels bitmapLock(bitmap);
 129
 130     if (bitmap.colorType() != kN32_SkColorType || !bitmap.getPixels())
 131         return false; // Only support 32 bit/pixel skia bitmaps.
 132
 133     return encodePixels(IntSize(bitmap.width(), bitmap.height()), static_cast<unsigned char *>(bitmap.getPixels()), true, quality, output);
 134 }
 135
 136 bool WEBPImageEncoder::encode(const ImageDataBuffer& imageData, int quality, Vector<unsigned char>* output)
 137 {
 138     return encodePixels(imageData.size(), imageData.data(), false, quality, output);
 139 }
 140
 141 } // namespace blink