| /* |
| * Copyright 2010, The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "SkImageDecoder.h" |
| #include "SkImageEncoder.h" |
| #include "SkColorPriv.h" |
| #include "SkScaledBitmapSampler.h" |
| #include "SkStream.h" |
| #include "SkTemplates.h" |
| #include "SkUtils.h" |
| |
| // A WebP decoder only, on top of (subset of) libwebp |
| // For more information on WebP image format, and libwebp library, see: |
| // http://code.google.com/speed/webp/ |
| // http://www.webmproject.org/code/#libwebp_webp_image_decoder_library |
| // http://review.webmproject.org/gitweb?p=libwebp.git |
| |
| #include <stdio.h> |
| extern "C" { |
| // If moving libwebp out of skia source tree, path for webp headers must be |
| // updated accordingly. Here, we enforce using local copy in webp sub-directory. |
| #include "webp/decode.h" |
| #include "webp/encode.h" |
| } |
| |
| // this enables timing code to report milliseconds for a decode |
| //#define TIME_DECODE |
| |
| ////////////////////////////////////////////////////////////////////////// |
| ////////////////////////////////////////////////////////////////////////// |
| |
| // Define VP8 I/O on top of Skia stream |
| |
| ////////////////////////////////////////////////////////////////////////// |
| ////////////////////////////////////////////////////////////////////////// |
| |
| static const size_t WEBP_VP8_HEADER_SIZE = 64; |
| static const size_t WEBP_IDECODE_BUFFER_SZ = (1 << 16); |
| |
| // Parse headers of RIFF container, and check for valid Webp (VP8) content. |
| static bool webp_parse_header(SkStream* stream, int* width, int* height, int* alpha) { |
| unsigned char buffer[WEBP_VP8_HEADER_SIZE]; |
| size_t bytesToRead = WEBP_VP8_HEADER_SIZE; |
| size_t totalBytesRead = 0; |
| do { |
| unsigned char* dst = buffer + totalBytesRead; |
| const size_t bytesRead = stream->read(dst, bytesToRead); |
| if (0 == bytesRead) { |
| // Could not read any bytes. Check to see if we are at the end (exit |
| // condition), and continue reading if not. Important for streams |
| // that do not have all the data ready. |
| continue; |
| } |
| bytesToRead -= bytesRead; |
| totalBytesRead += bytesRead; |
| SkASSERT(bytesToRead + totalBytesRead == WEBP_VP8_HEADER_SIZE); |
| } while (!stream->isAtEnd() && bytesToRead > 0); |
| |
| WebPBitstreamFeatures features; |
| VP8StatusCode status = WebPGetFeatures(buffer, totalBytesRead, &features); |
| if (VP8_STATUS_OK != status) { |
| return false; // Invalid WebP file. |
| } |
| *width = features.width; |
| *height = features.height; |
| *alpha = features.has_alpha; |
| |
| // sanity check for image size that's about to be decoded. |
| { |
| Sk64 size; |
| size.setMul(*width, *height); |
| if (size.isNeg() || !size.is32()) { |
| return false; |
| } |
| // now check that if we are 4-bytes per pixel, we also don't overflow |
| if (size.get32() > (0x7FFFFFFF >> 2)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| class SkWEBPImageDecoder: public SkImageDecoder { |
| public: |
| SkWEBPImageDecoder() { |
| fInputStream = NULL; |
| fOrigWidth = 0; |
| fOrigHeight = 0; |
| fHasAlpha = 0; |
| } |
| virtual ~SkWEBPImageDecoder() { |
| SkSafeUnref(fInputStream); |
| } |
| |
| virtual Format getFormat() const SK_OVERRIDE { |
| return kWEBP_Format; |
| } |
| |
| protected: |
| virtual bool onBuildTileIndex(SkStreamRewindable *stream, int *width, int *height) SK_OVERRIDE; |
| virtual bool onDecodeSubset(SkBitmap* bitmap, const SkIRect& rect) SK_OVERRIDE; |
| virtual bool onDecode(SkStream* stream, SkBitmap* bm, Mode) SK_OVERRIDE; |
| |
| private: |
| /** |
| * Called when determining the output config to request to webp. |
| * If the image does not have alpha, there is no need to premultiply. |
| * If the caller wants unpremultiplied colors, that is respected. |
| */ |
| bool shouldPremultiply() const { |
| return SkToBool(fHasAlpha) && !this->getRequireUnpremultipliedColors(); |
| } |
| |
| bool setDecodeConfig(SkBitmap* decodedBitmap, int width, int height); |
| |
| SkStream* fInputStream; |
| int fOrigWidth; |
| int fOrigHeight; |
| int fHasAlpha; |
| |
| typedef SkImageDecoder INHERITED; |
| }; |
| |
| ////////////////////////////////////////////////////////////////////////// |
| |
| #ifdef TIME_DECODE |
| |
| #include "SkTime.h" |
| |
| class AutoTimeMillis { |
| public: |
| AutoTimeMillis(const char label[]) : |
| fLabel(label) { |
| if (NULL == fLabel) { |
| fLabel = ""; |
| } |
| fNow = SkTime::GetMSecs(); |
| } |
| ~AutoTimeMillis() { |
| SkDebugf("---- Time (ms): %s %d\n", fLabel, SkTime::GetMSecs() - fNow); |
| } |
| private: |
| const char* fLabel; |
| SkMSec fNow; |
| }; |
| |
| #endif |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| // This guy exists just to aid in debugging, as it allows debuggers to just |
| // set a break-point in one place to see all error exists. |
| static bool return_false(const SkBitmap& bm, const char msg[]) { |
| SkDEBUGF(("libwebp error %s [%d %d]", msg, bm.width(), bm.height())); |
| return false; // must always return false |
| } |
| |
| static WEBP_CSP_MODE webp_decode_mode(const SkBitmap* decodedBitmap, bool premultiply) { |
| WEBP_CSP_MODE mode = MODE_LAST; |
| SkBitmap::Config config = decodedBitmap->config(); |
| |
| if (config == SkBitmap::kARGB_8888_Config) { |
| #if SK_PMCOLOR_BYTE_ORDER(B,G,R,A) |
| mode = premultiply ? MODE_bgrA : MODE_BGRA; |
| #elif SK_PMCOLOR_BYTE_ORDER(R,G,B,A) |
| mode = premultiply ? MODE_rgbA : MODE_RGBA; |
| #else |
| #error "Skia uses BGRA or RGBA byte order" |
| #endif |
| } else if (config == SkBitmap::kARGB_4444_Config) { |
| mode = premultiply ? MODE_rgbA_4444 : MODE_RGBA_4444; |
| } else if (config == SkBitmap::kRGB_565_Config) { |
| mode = MODE_RGB_565; |
| } |
| SkASSERT(MODE_LAST != mode); |
| return mode; |
| } |
| |
| // Incremental WebP image decoding. Reads input buffer of 64K size iteratively |
| // and decodes this block to appropriate color-space as per config object. |
| static bool webp_idecode(SkStream* stream, WebPDecoderConfig* config) { |
| WebPIDecoder* idec = WebPIDecode(NULL, 0, config); |
| if (NULL == idec) { |
| WebPFreeDecBuffer(&config->output); |
| return false; |
| } |
| |
| if (!stream->rewind()) { |
| SkDebugf("Failed to rewind webp stream!"); |
| return false; |
| } |
| const size_t readBufferSize = stream->hasLength() ? |
| SkTMin(stream->getLength(), WEBP_IDECODE_BUFFER_SZ) : WEBP_IDECODE_BUFFER_SZ; |
| SkAutoMalloc srcStorage(readBufferSize); |
| unsigned char* input = (uint8_t*)srcStorage.get(); |
| if (NULL == input) { |
| WebPIDelete(idec); |
| WebPFreeDecBuffer(&config->output); |
| return false; |
| } |
| |
| bool success = true; |
| VP8StatusCode status = VP8_STATUS_SUSPENDED; |
| do { |
| const size_t bytesRead = stream->read(input, readBufferSize); |
| if (0 == bytesRead) { |
| success = false; |
| break; |
| } |
| |
| status = WebPIAppend(idec, input, bytesRead); |
| if (VP8_STATUS_OK != status && VP8_STATUS_SUSPENDED != status) { |
| success = false; |
| break; |
| } |
| } while (VP8_STATUS_OK != status); |
| srcStorage.free(); |
| WebPIDelete(idec); |
| WebPFreeDecBuffer(&config->output); |
| |
| return success; |
| } |
| |
| static bool webp_get_config_resize(WebPDecoderConfig* config, |
| SkBitmap* decodedBitmap, |
| int width, int height, bool premultiply) { |
| WEBP_CSP_MODE mode = webp_decode_mode(decodedBitmap, premultiply); |
| if (MODE_LAST == mode) { |
| return false; |
| } |
| |
| if (0 == WebPInitDecoderConfig(config)) { |
| return false; |
| } |
| |
| config->output.colorspace = mode; |
| config->output.u.RGBA.rgba = (uint8_t*)decodedBitmap->getPixels(); |
| config->output.u.RGBA.stride = (int) decodedBitmap->rowBytes(); |
| config->output.u.RGBA.size = decodedBitmap->getSize(); |
| config->output.is_external_memory = 1; |
| |
| if (width != decodedBitmap->width() || height != decodedBitmap->height()) { |
| config->options.use_scaling = 1; |
| config->options.scaled_width = decodedBitmap->width(); |
| config->options.scaled_height = decodedBitmap->height(); |
| } |
| |
| return true; |
| } |
| |
| static bool webp_get_config_resize_crop(WebPDecoderConfig* config, |
| SkBitmap* decodedBitmap, |
| const SkIRect& region, bool premultiply) { |
| |
| if (!webp_get_config_resize(config, decodedBitmap, region.width(), |
| region.height(), premultiply)) { |
| return false; |
| } |
| |
| config->options.use_cropping = 1; |
| config->options.crop_left = region.fLeft; |
| config->options.crop_top = region.fTop; |
| config->options.crop_width = region.width(); |
| config->options.crop_height = region.height(); |
| |
| return true; |
| } |
| |
| bool SkWEBPImageDecoder::setDecodeConfig(SkBitmap* decodedBitmap, |
| int width, int height) { |
| SkBitmap::Config config = this->getPrefConfig(k32Bit_SrcDepth, SkToBool(fHasAlpha)); |
| |
| // YUV converter supports output in RGB565, RGBA4444 and RGBA8888 formats. |
| if (fHasAlpha) { |
| if (config != SkBitmap::kARGB_4444_Config) { |
| config = SkBitmap::kARGB_8888_Config; |
| } |
| } else { |
| if (config != SkBitmap::kRGB_565_Config && |
| config != SkBitmap::kARGB_4444_Config) { |
| config = SkBitmap::kARGB_8888_Config; |
| } |
| } |
| |
| if (!this->chooseFromOneChoice(config, width, height)) { |
| return false; |
| } |
| |
| return decodedBitmap->setConfig(config, width, height, 0, |
| fHasAlpha ? kPremul_SkAlphaType : kOpaque_SkAlphaType); |
| } |
| |
| bool SkWEBPImageDecoder::onBuildTileIndex(SkStreamRewindable* stream, |
| int *width, int *height) { |
| int origWidth, origHeight, hasAlpha; |
| if (!webp_parse_header(stream, &origWidth, &origHeight, &hasAlpha)) { |
| return false; |
| } |
| |
| if (!stream->rewind()) { |
| SkDebugf("Failed to rewind webp stream!"); |
| return false; |
| } |
| |
| *width = origWidth; |
| *height = origHeight; |
| |
| SkRefCnt_SafeAssign(this->fInputStream, stream); |
| this->fOrigWidth = origWidth; |
| this->fOrigHeight = origHeight; |
| this->fHasAlpha = hasAlpha; |
| |
| return true; |
| } |
| |
| static bool is_config_compatible(const SkBitmap& bitmap) { |
| SkBitmap::Config config = bitmap.config(); |
| return config == SkBitmap::kARGB_4444_Config || |
| config == SkBitmap::kRGB_565_Config || |
| config == SkBitmap::kARGB_8888_Config; |
| } |
| |
| bool SkWEBPImageDecoder::onDecodeSubset(SkBitmap* decodedBitmap, |
| const SkIRect& region) { |
| SkIRect rect = SkIRect::MakeWH(fOrigWidth, fOrigHeight); |
| |
| if (!rect.intersect(region)) { |
| // If the requested region is entirely outsides the image, return false |
| return false; |
| } |
| |
| const int sampleSize = this->getSampleSize(); |
| SkScaledBitmapSampler sampler(rect.width(), rect.height(), sampleSize); |
| const int width = sampler.scaledWidth(); |
| const int height = sampler.scaledHeight(); |
| |
| // The image can be decoded directly to decodedBitmap if |
| // 1. the region is within the image range |
| // 2. bitmap's config is compatible |
| // 3. bitmap's size is same as the required region (after sampled) |
| bool directDecode = (rect == region) && |
| (decodedBitmap->isNull() || |
| (is_config_compatible(*decodedBitmap) && |
| (decodedBitmap->width() == width) && |
| (decodedBitmap->height() == height))); |
| |
| SkBitmap tmpBitmap; |
| SkBitmap *bitmap = decodedBitmap; |
| |
| if (!directDecode) { |
| bitmap = &tmpBitmap; |
| } |
| |
| if (bitmap->isNull()) { |
| if (!setDecodeConfig(bitmap, width, height)) { |
| return false; |
| } |
| // alloc from native heap if it is a temp bitmap. (prevent GC) |
| bool allocResult = (bitmap == decodedBitmap) |
| ? allocPixelRef(bitmap, NULL) |
| : bitmap->allocPixels(); |
| if (!allocResult) { |
| return return_false(*decodedBitmap, "allocPixelRef"); |
| } |
| } else { |
| // This is also called in setDecodeConfig in above block. |
| // i.e., when bitmap->isNull() is true. |
| if (!chooseFromOneChoice(bitmap->config(), width, height)) { |
| return false; |
| } |
| } |
| |
| SkAutoLockPixels alp(*bitmap); |
| WebPDecoderConfig config; |
| if (!webp_get_config_resize_crop(&config, bitmap, rect, |
| this->shouldPremultiply())) { |
| return false; |
| } |
| |
| // Decode the WebP image data stream using WebP incremental decoding for |
| // the specified cropped image-region. |
| if (!webp_idecode(this->fInputStream, &config)) { |
| return false; |
| } |
| |
| if (!directDecode) { |
| cropBitmap(decodedBitmap, bitmap, sampleSize, region.x(), region.y(), |
| region.width(), region.height(), rect.x(), rect.y()); |
| } |
| return true; |
| } |
| |
| bool SkWEBPImageDecoder::onDecode(SkStream* stream, SkBitmap* decodedBitmap, |
| Mode mode) { |
| #ifdef TIME_DECODE |
| AutoTimeMillis atm("WEBP Decode"); |
| #endif |
| |
| int origWidth, origHeight, hasAlpha; |
| if (!webp_parse_header(stream, &origWidth, &origHeight, &hasAlpha)) { |
| return false; |
| } |
| this->fHasAlpha = hasAlpha; |
| |
| const int sampleSize = this->getSampleSize(); |
| SkScaledBitmapSampler sampler(origWidth, origHeight, sampleSize); |
| if (!setDecodeConfig(decodedBitmap, sampler.scaledWidth(), |
| sampler.scaledHeight())) { |
| return false; |
| } |
| |
| // If only bounds are requested, done |
| if (SkImageDecoder::kDecodeBounds_Mode == mode) { |
| return true; |
| } |
| |
| if (!this->allocPixelRef(decodedBitmap, NULL)) { |
| return return_false(*decodedBitmap, "allocPixelRef"); |
| } |
| |
| SkAutoLockPixels alp(*decodedBitmap); |
| |
| WebPDecoderConfig config; |
| if (!webp_get_config_resize(&config, decodedBitmap, origWidth, origHeight, |
| this->shouldPremultiply())) { |
| return false; |
| } |
| |
| // Decode the WebP image data stream using WebP incremental decoding. |
| return webp_idecode(stream, &config); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| typedef void (*ScanlineImporter)(const uint8_t* in, uint8_t* out, int width, |
| const SkPMColor* SK_RESTRICT ctable); |
| |
| static void ARGB_8888_To_RGB(const uint8_t* in, uint8_t* rgb, int width, |
| const SkPMColor*) { |
| const uint32_t* SK_RESTRICT src = (const uint32_t*)in; |
| for (int i = 0; i < width; ++i) { |
| const uint32_t c = *src++; |
| rgb[0] = SkGetPackedR32(c); |
| rgb[1] = SkGetPackedG32(c); |
| rgb[2] = SkGetPackedB32(c); |
| rgb += 3; |
| } |
| } |
| |
| static void RGB_565_To_RGB(const uint8_t* in, uint8_t* rgb, int width, |
| const SkPMColor*) { |
| const uint16_t* SK_RESTRICT src = (const uint16_t*)in; |
| for (int i = 0; i < width; ++i) { |
| const uint16_t c = *src++; |
| rgb[0] = SkPacked16ToR32(c); |
| rgb[1] = SkPacked16ToG32(c); |
| rgb[2] = SkPacked16ToB32(c); |
| rgb += 3; |
| } |
| } |
| |
| static void ARGB_4444_To_RGB(const uint8_t* in, uint8_t* rgb, int width, |
| const SkPMColor*) { |
| const SkPMColor16* SK_RESTRICT src = (const SkPMColor16*)in; |
| for (int i = 0; i < width; ++i) { |
| const SkPMColor16 c = *src++; |
| rgb[0] = SkPacked4444ToR32(c); |
| rgb[1] = SkPacked4444ToG32(c); |
| rgb[2] = SkPacked4444ToB32(c); |
| rgb += 3; |
| } |
| } |
| |
| static void Index8_To_RGB(const uint8_t* in, uint8_t* rgb, int width, |
| const SkPMColor* SK_RESTRICT ctable) { |
| const uint8_t* SK_RESTRICT src = (const uint8_t*)in; |
| for (int i = 0; i < width; ++i) { |
| const uint32_t c = ctable[*src++]; |
| rgb[0] = SkGetPackedR32(c); |
| rgb[1] = SkGetPackedG32(c); |
| rgb[2] = SkGetPackedB32(c); |
| rgb += 3; |
| } |
| } |
| |
| static ScanlineImporter ChooseImporter(const SkBitmap::Config& config) { |
| switch (config) { |
| case SkBitmap::kARGB_8888_Config: |
| return ARGB_8888_To_RGB; |
| case SkBitmap::kRGB_565_Config: |
| return RGB_565_To_RGB; |
| case SkBitmap::kARGB_4444_Config: |
| return ARGB_4444_To_RGB; |
| case SkBitmap::kIndex8_Config: |
| return Index8_To_RGB; |
| default: |
| return NULL; |
| } |
| } |
| |
| static int stream_writer(const uint8_t* data, size_t data_size, |
| const WebPPicture* const picture) { |
| SkWStream* const stream = (SkWStream*)picture->custom_ptr; |
| return stream->write(data, data_size) ? 1 : 0; |
| } |
| |
| class SkWEBPImageEncoder : public SkImageEncoder { |
| protected: |
| virtual bool onEncode(SkWStream* stream, const SkBitmap& bm, int quality) SK_OVERRIDE; |
| |
| private: |
| typedef SkImageEncoder INHERITED; |
| }; |
| |
| bool SkWEBPImageEncoder::onEncode(SkWStream* stream, const SkBitmap& bm, |
| int quality) { |
| const SkBitmap::Config config = bm.config(); |
| const ScanlineImporter scanline_import = ChooseImporter(config); |
| if (NULL == scanline_import) { |
| return false; |
| } |
| |
| SkAutoLockPixels alp(bm); |
| SkAutoLockColors ctLocker; |
| if (NULL == bm.getPixels()) { |
| return false; |
| } |
| |
| WebPConfig webp_config; |
| if (!WebPConfigPreset(&webp_config, WEBP_PRESET_DEFAULT, (float) quality)) { |
| return false; |
| } |
| |
| WebPPicture pic; |
| WebPPictureInit(&pic); |
| pic.width = bm.width(); |
| pic.height = bm.height(); |
| pic.writer = stream_writer; |
| pic.custom_ptr = (void*)stream; |
| |
| const SkPMColor* colors = ctLocker.lockColors(bm); |
| const uint8_t* src = (uint8_t*)bm.getPixels(); |
| const int rgbStride = pic.width * 3; |
| |
| // Import (for each scanline) the bit-map image (in appropriate color-space) |
| // to RGB color space. |
| uint8_t* rgb = new uint8_t[rgbStride * pic.height]; |
| for (int y = 0; y < pic.height; ++y) { |
| scanline_import(src + y * bm.rowBytes(), rgb + y * rgbStride, |
| pic.width, colors); |
| } |
| |
| bool ok = SkToBool(WebPPictureImportRGB(&pic, rgb, rgbStride)); |
| delete[] rgb; |
| |
| ok = ok && WebPEncode(&webp_config, &pic); |
| WebPPictureFree(&pic); |
| |
| return ok; |
| } |
| |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| DEFINE_DECODER_CREATOR(WEBPImageDecoder); |
| DEFINE_ENCODER_CREATOR(WEBPImageEncoder); |
| /////////////////////////////////////////////////////////////////////////////// |
| |
| static SkImageDecoder* sk_libwebp_dfactory(SkStreamRewindable* stream) { |
| int width, height, hasAlpha; |
| if (!webp_parse_header(stream, &width, &height, &hasAlpha)) { |
| return NULL; |
| } |
| |
| // Magic matches, call decoder |
| return SkNEW(SkWEBPImageDecoder); |
| } |
| |
| static SkImageDecoder::Format get_format_webp(SkStreamRewindable* stream) { |
| int width, height, hasAlpha; |
| if (webp_parse_header(stream, &width, &height, &hasAlpha)) { |
| return SkImageDecoder::kWEBP_Format; |
| } |
| return SkImageDecoder::kUnknown_Format; |
| } |
| |
| static SkImageEncoder* sk_libwebp_efactory(SkImageEncoder::Type t) { |
| return (SkImageEncoder::kWEBP_Type == t) ? SkNEW(SkWEBPImageEncoder) : NULL; |
| } |
| |
| static SkImageDecoder_DecodeReg gDReg(sk_libwebp_dfactory); |
| static SkImageDecoder_FormatReg gFormatReg(get_format_webp); |
| static SkImageEncoder_EncodeReg gEReg(sk_libwebp_efactory); |