diff options
Diffstat (limited to 'src/images/SkImageDecoder_libwebp.cpp')
-rw-r--r-- | src/images/SkImageDecoder_libwebp.cpp | 314 |
1 files changed, 1 insertions, 313 deletions
diff --git a/src/images/SkImageDecoder_libwebp.cpp b/src/images/SkImageDecoder_libwebp.cpp index 2db08cee83..116608a253 100644 --- a/src/images/SkImageDecoder_libwebp.cpp +++ b/src/images/SkImageDecoder_libwebp.cpp @@ -14,10 +14,9 @@ * limitations under the License. */ -#include "SkImageDecoder.h" +#include "SkBitmap.h" #include "SkImageEncoder.h" #include "SkColorPriv.h" -#include "SkScaledBitmapSampler.h" #include "SkStream.h" #include "SkTemplates.h" #include "SkUtils.h" @@ -32,299 +31,9 @@ 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) { - SkASSERT(stream->isAtEnd()); - break; - } - 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. - { - int64_t size = sk_64_mul(*width, *height); - if (!sk_64_isS32(size)) { - return false; - } - // now check that if we are 4-bytes per pixel, we also don't overflow - if (sk_64_asS32(size) > (0x7FFFFFFF >> 2)) { - return false; - } - } - return true; -} - -class SkWEBPImageDecoder: public SkImageDecoder { -public: - SkWEBPImageDecoder() { - fOrigWidth = 0; - fOrigHeight = 0; - fHasAlpha = 0; - } - - Format getFormat() const override { - return kWEBP_Format; - } - -protected: - Result onDecode(SkStream* stream, SkBitmap* bm, Mode) 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); - - SkAutoTDelete<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 (nullptr == 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 void print_webp_error(const SkBitmap& bm, const char msg[]) { - SkDEBUGF(("libwebp error %s [%d %d]", msg, bm.width(), bm.height())); -} - -static SkImageDecoder::Result return_failure(const SkBitmap& bm, const char msg[]) { - print_webp_error(bm, msg); - return SkImageDecoder::kFailure; // must always return kFailure -} - -/////////////////////////////////////////////////////////////////////////////// - -static WEBP_CSP_MODE webp_decode_mode(const SkBitmap* decodedBitmap, bool premultiply) { - WEBP_CSP_MODE mode = MODE_LAST; - const SkColorType ct = decodedBitmap->colorType(); - - if (ct == kN32_SkColorType) { - #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 (ct == kARGB_4444_SkColorType) { - mode = premultiply ? MODE_rgbA_4444 : MODE_RGBA_4444; - } else if (ct == kRGB_565_SkColorType) { - 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(nullptr, 0, config); - if (nullptr == 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; - SkAutoTMalloc<unsigned char> srcStorage(readBufferSize); - unsigned char* input = srcStorage.get(); - if (nullptr == 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.reset(); - 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; -} - -bool SkWEBPImageDecoder::setDecodeConfig(SkBitmap* decodedBitmap, int width, int height) { - SkColorType colorType = this->getPrefColorType(k32Bit_SrcDepth, SkToBool(fHasAlpha)); - - // YUV converter supports output in RGB565, RGBA4444 and RGBA8888 formats. - if (fHasAlpha) { - if (colorType != kARGB_4444_SkColorType) { - colorType = kN32_SkColorType; - } - } else { - if (colorType != kRGB_565_SkColorType && colorType != kARGB_4444_SkColorType) { - colorType = kN32_SkColorType; - } - } - - SkAlphaType alphaType = kOpaque_SkAlphaType; - if (SkToBool(fHasAlpha)) { - if (this->getRequireUnpremultipliedColors()) { - alphaType = kUnpremul_SkAlphaType; - } else { - alphaType = kPremul_SkAlphaType; - } - } - return decodedBitmap->setInfo(SkImageInfo::Make(width, height, colorType, alphaType)); -} - -SkImageDecoder::Result 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 kFailure; - } - this->fHasAlpha = hasAlpha; - - const int sampleSize = this->getSampleSize(); - SkScaledBitmapSampler sampler(origWidth, origHeight, sampleSize); - if (!setDecodeConfig(decodedBitmap, sampler.scaledWidth(), - sampler.scaledHeight())) { - return kFailure; - } - - // If only bounds are requested, done - if (SkImageDecoder::kDecodeBounds_Mode == mode) { - return kSuccess; - } - - if (!this->allocPixelRef(decodedBitmap, nullptr)) { - return return_failure(*decodedBitmap, "allocPixelRef"); - } - - SkAutoLockPixels alp(*decodedBitmap); - - WebPDecoderConfig config; - if (!webp_get_config_resize(&config, decodedBitmap, origWidth, origHeight, - this->shouldPremultiply())) { - return kFailure; - } - - // Decode the WebP image data stream using WebP incremental decoding. - return webp_idecode(stream, &config) ? kSuccess : kFailure; -} - -/////////////////////////////////////////////////////////////////////////////// - #include "SkUnPreMultiply.h" typedef void (*ScanlineImporter)(const uint8_t* in, uint8_t* out, int width, @@ -528,32 +237,11 @@ bool SkWEBPImageEncoder::onEncode(SkWStream* stream, const SkBitmap& bm, /////////////////////////////////////////////////////////////////////////////// -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 nullptr; - } - - // Magic matches, call decoder - return new 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) ? new SkWEBPImageEncoder : nullptr; } -static SkImageDecoder_DecodeReg gDReg(sk_libwebp_dfactory); -static SkImageDecoder_FormatReg gFormatReg(get_format_webp); static SkImageEncoder_EncodeReg gEReg(sk_libwebp_efactory); |