Delete SkImageDecoder

src/images/SkImageDecoder_libwebp.cpp

Index: src/images/SkImageDecoder_libwebp.cpp
diff --git a/src/images/SkImageDecoder_libwebp.cpp b/src/images/SkImageDecoder_libwebp.cpp
index 2db08cee83dd5fd3ceb054a2e515ae12af8cd2cf..116608a253e2d1db65bc5b2d3e5258bf7c285435 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);