| /* |
| * Copyright 2018 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "src/codec/SkWuffsCodec.h" |
| |
| #include "include/codec/SkCodecAnimation.h" |
| #include "include/core/SkAlphaType.h" |
| #include "include/core/SkBitmap.h" |
| #include "include/core/SkBlendMode.h" |
| #include "include/core/SkColorType.h" |
| #include "include/core/SkEncodedImageFormat.h" |
| #include "include/core/SkImageInfo.h" |
| #include "include/core/SkMatrix.h" |
| #include "include/core/SkPaint.h" |
| #include "include/core/SkPixmap.h" |
| #include "include/core/SkRect.h" |
| #include "include/core/SkSamplingOptions.h" |
| #include "include/core/SkSize.h" |
| #include "include/core/SkStream.h" |
| #include "include/core/SkTypes.h" |
| #include "include/private/SkEncodedInfo.h" |
| #include "include/private/base/SkMalloc.h" |
| #include "include/private/base/SkTo.h" |
| #include "modules/skcms/skcms.h" |
| #include "src/codec/SkCodecPriv.h" |
| #include "src/codec/SkFrameHolder.h" |
| #include "src/codec/SkSampler.h" |
| #include "src/codec/SkScalingCodec.h" |
| #include "src/core/SkDraw.h" |
| #include "src/core/SkMatrixProvider.h" |
| #include "src/core/SkRasterClip.h" |
| #include "src/core/SkStreamPriv.h" |
| |
| #include <climits> |
| #include <cstdint> |
| #include <cstring> |
| #include <utility> |
| #include <vector> |
| |
| // Documentation on the Wuffs language and standard library (in general) and |
| // its image decoding API (in particular) is at: |
| // |
| // - https://github.com/google/wuffs/tree/master/doc |
| // - https://github.com/google/wuffs/blob/master/doc/std/image-decoders.md |
| |
| // Wuffs ships as a "single file C library" or "header file library" as per |
| // https://github.com/nothings/stb/blob/master/docs/stb_howto.txt |
| // |
| // As we have not #define'd WUFFS_IMPLEMENTATION, the #include here is |
| // including a header file, even though that file name ends in ".c". |
| #if defined(WUFFS_IMPLEMENTATION) |
| #error "SkWuffsCodec should not #define WUFFS_IMPLEMENTATION" |
| #endif |
| #include "wuffs-v0.3.c" |
| // Commit count 2514 is Wuffs 0.3.0-alpha.4. |
| #if WUFFS_VERSION_BUILD_METADATA_COMMIT_COUNT < 2514 |
| #error "Wuffs version is too old. Upgrade to the latest version." |
| #endif |
| |
| #define SK_WUFFS_CODEC_BUFFER_SIZE 4096 |
| |
| // Configuring a Skia build with |
| // SK_WUFFS_FAVORS_PERFORMANCE_OVER_ADDITIONAL_MEMORY_SAFETY can improve decode |
| // performance by some fixed amount (independent of the image size), which can |
| // be a noticeable proportional improvement if the input is relatively small. |
| // |
| // The Wuffs library is still memory-safe either way, in that there are no |
| // out-of-bounds reads or writes, and the library endeavours not to read |
| // uninitialized memory. There are just fewer compiler-enforced guarantees |
| // against reading uninitialized memory. For more detail, see |
| // https://github.com/google/wuffs/blob/master/doc/note/initialization.md#partial-zero-initialization |
| #if defined(SK_WUFFS_FAVORS_PERFORMANCE_OVER_ADDITIONAL_MEMORY_SAFETY) |
| #define SK_WUFFS_INITIALIZE_FLAGS WUFFS_INITIALIZE__LEAVE_INTERNAL_BUFFERS_UNINITIALIZED |
| #else |
| #define SK_WUFFS_INITIALIZE_FLAGS WUFFS_INITIALIZE__DEFAULT_OPTIONS |
| #endif |
| |
| static bool fill_buffer(wuffs_base__io_buffer* b, SkStream* s) { |
| b->compact(); |
| size_t num_read = s->read(b->data.ptr + b->meta.wi, b->data.len - b->meta.wi); |
| b->meta.wi += num_read; |
| b->meta.closed = s->isAtEnd(); |
| return num_read > 0; |
| } |
| |
| static bool seek_buffer(wuffs_base__io_buffer* b, SkStream* s, uint64_t pos) { |
| // Try to re-position the io_buffer's meta.ri read-index first, which is |
| // cheaper than seeking in the backing SkStream. |
| if ((pos >= b->meta.pos) && (pos - b->meta.pos <= b->meta.wi)) { |
| b->meta.ri = pos - b->meta.pos; |
| return true; |
| } |
| // Seek in the backing SkStream. |
| if ((pos > SIZE_MAX) || (!s->seek(pos))) { |
| return false; |
| } |
| b->meta.wi = 0; |
| b->meta.ri = 0; |
| b->meta.pos = pos; |
| b->meta.closed = false; |
| return true; |
| } |
| |
| static SkCodecAnimation::DisposalMethod wuffs_disposal_to_skia_disposal( |
| wuffs_base__animation_disposal w) { |
| switch (w) { |
| case WUFFS_BASE__ANIMATION_DISPOSAL__RESTORE_BACKGROUND: |
| return SkCodecAnimation::DisposalMethod::kRestoreBGColor; |
| case WUFFS_BASE__ANIMATION_DISPOSAL__RESTORE_PREVIOUS: |
| return SkCodecAnimation::DisposalMethod::kRestorePrevious; |
| default: |
| return SkCodecAnimation::DisposalMethod::kKeep; |
| } |
| } |
| |
| static SkAlphaType to_alpha_type(bool opaque) { |
| return opaque ? kOpaque_SkAlphaType : kPremul_SkAlphaType; |
| } |
| |
| static SkCodec::Result reset_and_decode_image_config(wuffs_gif__decoder* decoder, |
| wuffs_base__image_config* imgcfg, |
| wuffs_base__io_buffer* b, |
| SkStream* s) { |
| // Calling decoder->initialize will memset most or all of it to zero, |
| // depending on SK_WUFFS_INITIALIZE_FLAGS. |
| wuffs_base__status status = |
| decoder->initialize(sizeof__wuffs_gif__decoder(), WUFFS_VERSION, SK_WUFFS_INITIALIZE_FLAGS); |
| if (status.repr != nullptr) { |
| SkCodecPrintf("initialize: %s", status.message()); |
| return SkCodec::kInternalError; |
| } |
| |
| // See https://bugs.chromium.org/p/skia/issues/detail?id=12055 |
| decoder->set_quirk_enabled(WUFFS_GIF__QUIRK_IGNORE_TOO_MUCH_PIXEL_DATA, true); |
| |
| while (true) { |
| status = decoder->decode_image_config(imgcfg, b); |
| if (status.repr == nullptr) { |
| break; |
| } else if (status.repr != wuffs_base__suspension__short_read) { |
| SkCodecPrintf("decode_image_config: %s", status.message()); |
| return SkCodec::kErrorInInput; |
| } else if (!fill_buffer(b, s)) { |
| return SkCodec::kIncompleteInput; |
| } |
| } |
| |
| // A GIF image's natural color model is indexed color: 1 byte per pixel, |
| // indexing a 256-element palette. |
| // |
| // For Skia, we override that to decode to 4 bytes per pixel, BGRA or RGBA. |
| uint32_t pixfmt = WUFFS_BASE__PIXEL_FORMAT__INVALID; |
| switch (kN32_SkColorType) { |
| case kBGRA_8888_SkColorType: |
| pixfmt = WUFFS_BASE__PIXEL_FORMAT__BGRA_NONPREMUL; |
| break; |
| case kRGBA_8888_SkColorType: |
| pixfmt = WUFFS_BASE__PIXEL_FORMAT__RGBA_NONPREMUL; |
| break; |
| default: |
| return SkCodec::kInternalError; |
| } |
| if (imgcfg) { |
| imgcfg->pixcfg.set(pixfmt, WUFFS_BASE__PIXEL_SUBSAMPLING__NONE, imgcfg->pixcfg.width(), |
| imgcfg->pixcfg.height()); |
| } |
| |
| return SkCodec::kSuccess; |
| } |
| |
| // -------------------------------- Class definitions |
| |
| class SkWuffsCodec; |
| |
| class SkWuffsFrame final : public SkFrame { |
| public: |
| SkWuffsFrame(wuffs_base__frame_config* fc); |
| |
| uint64_t ioPosition() const; |
| |
| // SkFrame overrides. |
| SkEncodedInfo::Alpha onReportedAlpha() const override; |
| |
| private: |
| uint64_t fIOPosition; |
| SkEncodedInfo::Alpha fReportedAlpha; |
| |
| using INHERITED = SkFrame; |
| }; |
| |
| // SkWuffsFrameHolder is a trivial indirector that forwards its calls onto a |
| // SkWuffsCodec. It is a separate class as SkWuffsCodec would otherwise |
| // inherit from both SkCodec and SkFrameHolder, and Skia style discourages |
| // multiple inheritance (e.g. with its "typedef Foo INHERITED" convention). |
| class SkWuffsFrameHolder final : public SkFrameHolder { |
| public: |
| SkWuffsFrameHolder() : INHERITED() {} |
| |
| void init(SkWuffsCodec* codec, int width, int height); |
| |
| // SkFrameHolder overrides. |
| const SkFrame* onGetFrame(int i) const override; |
| |
| private: |
| const SkWuffsCodec* fCodec; |
| |
| using INHERITED = SkFrameHolder; |
| }; |
| |
| class SkWuffsCodec final : public SkScalingCodec { |
| public: |
| SkWuffsCodec(SkEncodedInfo&& encodedInfo, |
| std::unique_ptr<SkStream> stream, |
| std::unique_ptr<wuffs_gif__decoder, decltype(&sk_free)> dec, |
| std::unique_ptr<uint8_t, decltype(&sk_free)> workbuf_ptr, |
| size_t workbuf_len, |
| wuffs_base__image_config imgcfg, |
| wuffs_base__io_buffer iobuf); |
| |
| const SkWuffsFrame* frame(int i) const; |
| |
| private: |
| // SkCodec overrides. |
| SkEncodedImageFormat onGetEncodedFormat() const override; |
| Result onGetPixels(const SkImageInfo&, void*, size_t, const Options&, int*) override; |
| const SkFrameHolder* getFrameHolder() const override; |
| Result onStartIncrementalDecode(const SkImageInfo& dstInfo, |
| void* dst, |
| size_t rowBytes, |
| const SkCodec::Options& options) override; |
| Result onIncrementalDecode(int* rowsDecoded) override; |
| int onGetFrameCount() override; |
| bool onGetFrameInfo(int, FrameInfo*) const override; |
| int onGetRepetitionCount() override; |
| |
| // Two separate implementations of onStartIncrementalDecode and |
| // onIncrementalDecode, named "one pass" and "two pass" decoding. One pass |
| // decoding writes directly from the Wuffs image decoder to the dst buffer |
| // (the dst argument to onStartIncrementalDecode). Two pass decoding first |
| // writes into an intermediate buffer, and then composites and transforms |
| // the intermediate buffer into the dst buffer. |
| // |
| // In the general case, we need the two pass decoder, because of Skia API |
| // features that Wuffs doesn't support (e.g. color correction, scaling, |
| // RGB565). But as an optimization, we use one pass decoding (it's faster |
| // and uses less memory) if applicable (see the assignment to |
| // fIncrDecOnePass that calculates when we can do so). |
| Result onStartIncrementalDecodeOnePass(const SkImageInfo& dstInfo, |
| uint8_t* dst, |
| size_t rowBytes, |
| const SkCodec::Options& options, |
| uint32_t pixelFormat, |
| size_t bytesPerPixel); |
| Result onStartIncrementalDecodeTwoPass(); |
| Result onIncrementalDecodeOnePass(); |
| Result onIncrementalDecodeTwoPass(); |
| |
| void onGetFrameCountInternal(); |
| Result seekFrame(int frameIndex); |
| Result resetDecoder(); |
| const char* decodeFrameConfig(); |
| const char* decodeFrame(); |
| void updateNumFullyReceivedFrames(); |
| |
| SkWuffsFrameHolder fFrameHolder; |
| std::unique_ptr<SkStream> fStream; |
| std::unique_ptr<uint8_t, decltype(&sk_free)> fWorkbufPtr; |
| size_t fWorkbufLen; |
| |
| std::unique_ptr<wuffs_gif__decoder, decltype(&sk_free)> fDecoder; |
| |
| const uint64_t fFirstFrameIOPosition; |
| wuffs_base__frame_config fFrameConfig; |
| wuffs_base__pixel_config fPixelConfig; |
| wuffs_base__pixel_buffer fPixelBuffer; |
| wuffs_base__io_buffer fIOBuffer; |
| |
| // Incremental decoding state. |
| uint8_t* fIncrDecDst; |
| size_t fIncrDecRowBytes; |
| wuffs_base__pixel_blend fIncrDecPixelBlend; |
| bool fIncrDecOnePass; |
| bool fFirstCallToIncrementalDecode; |
| |
| // Lazily allocated intermediate pixel buffer, for two pass decoding. |
| std::unique_ptr<uint8_t, decltype(&sk_free)> fTwoPassPixbufPtr; |
| size_t fTwoPassPixbufLen; |
| |
| uint64_t fNumFullyReceivedFrames; |
| std::vector<SkWuffsFrame> fFrames; |
| bool fFramesComplete; |
| |
| // If calling an fDecoder method returns an incomplete status, then |
| // fDecoder is suspended in a coroutine (i.e. waiting on I/O or halted on a |
| // non-recoverable error). To keep its internal proof-of-safety invariants |
| // consistent, there's only two things you can safely do with a suspended |
| // Wuffs object: resume the coroutine, or reset all state (memset to zero |
| // and start again). |
| // |
| // If fDecoderIsSuspended, and we aren't sure that we're going to resume |
| // the coroutine, then we will need to call this->resetDecoder before |
| // calling other fDecoder methods. |
| bool fDecoderIsSuspended; |
| |
| uint8_t fBuffer[SK_WUFFS_CODEC_BUFFER_SIZE]; |
| |
| using INHERITED = SkScalingCodec; |
| }; |
| |
| // -------------------------------- SkWuffsFrame implementation |
| |
| SkWuffsFrame::SkWuffsFrame(wuffs_base__frame_config* fc) |
| : INHERITED(fc->index()), |
| fIOPosition(fc->io_position()), |
| fReportedAlpha(fc->opaque_within_bounds() ? SkEncodedInfo::kOpaque_Alpha |
| : SkEncodedInfo::kUnpremul_Alpha) { |
| wuffs_base__rect_ie_u32 r = fc->bounds(); |
| this->setXYWH(r.min_incl_x, r.min_incl_y, r.width(), r.height()); |
| this->setDisposalMethod(wuffs_disposal_to_skia_disposal(fc->disposal())); |
| this->setDuration(fc->duration() / WUFFS_BASE__FLICKS_PER_MILLISECOND); |
| this->setBlend(fc->overwrite_instead_of_blend() ? SkCodecAnimation::Blend::kSrc |
| : SkCodecAnimation::Blend::kSrcOver); |
| } |
| |
| uint64_t SkWuffsFrame::ioPosition() const { |
| return fIOPosition; |
| } |
| |
| SkEncodedInfo::Alpha SkWuffsFrame::onReportedAlpha() const { |
| return fReportedAlpha; |
| } |
| |
| // -------------------------------- SkWuffsFrameHolder implementation |
| |
| void SkWuffsFrameHolder::init(SkWuffsCodec* codec, int width, int height) { |
| fCodec = codec; |
| // Initialize SkFrameHolder's (the superclass) fields. |
| fScreenWidth = width; |
| fScreenHeight = height; |
| } |
| |
| const SkFrame* SkWuffsFrameHolder::onGetFrame(int i) const { |
| return fCodec->frame(i); |
| } |
| |
| // -------------------------------- SkWuffsCodec implementation |
| |
| SkWuffsCodec::SkWuffsCodec(SkEncodedInfo&& encodedInfo, |
| std::unique_ptr<SkStream> stream, |
| std::unique_ptr<wuffs_gif__decoder, decltype(&sk_free)> dec, |
| std::unique_ptr<uint8_t, decltype(&sk_free)> workbuf_ptr, |
| size_t workbuf_len, |
| wuffs_base__image_config imgcfg, |
| wuffs_base__io_buffer iobuf) |
| : INHERITED(std::move(encodedInfo), |
| skcms_PixelFormat_RGBA_8888, |
| // Pass a nullptr SkStream to the SkCodec constructor. We |
| // manage the stream ourselves, as the default SkCodec behavior |
| // is too trigger-happy on rewinding the stream. |
| nullptr), |
| fFrameHolder(), |
| fStream(std::move(stream)), |
| fWorkbufPtr(std::move(workbuf_ptr)), |
| fWorkbufLen(workbuf_len), |
| fDecoder(std::move(dec)), |
| fFirstFrameIOPosition(imgcfg.first_frame_io_position()), |
| fFrameConfig(wuffs_base__null_frame_config()), |
| fPixelConfig(imgcfg.pixcfg), |
| fPixelBuffer(wuffs_base__null_pixel_buffer()), |
| fIOBuffer(wuffs_base__empty_io_buffer()), |
| fIncrDecDst(nullptr), |
| fIncrDecRowBytes(0), |
| fIncrDecPixelBlend(WUFFS_BASE__PIXEL_BLEND__SRC), |
| fIncrDecOnePass(false), |
| fFirstCallToIncrementalDecode(false), |
| fTwoPassPixbufPtr(nullptr, &sk_free), |
| fTwoPassPixbufLen(0), |
| fNumFullyReceivedFrames(0), |
| fFramesComplete(false), |
| fDecoderIsSuspended(false) { |
| fFrameHolder.init(this, imgcfg.pixcfg.width(), imgcfg.pixcfg.height()); |
| |
| // Initialize fIOBuffer's fields, copying any outstanding data from iobuf to |
| // fIOBuffer, as iobuf's backing array may not be valid for the lifetime of |
| // this SkWuffsCodec object, but fIOBuffer's backing array (fBuffer) is. |
| SkASSERT(iobuf.data.len == SK_WUFFS_CODEC_BUFFER_SIZE); |
| memmove(fBuffer, iobuf.data.ptr, iobuf.meta.wi); |
| fIOBuffer.data = wuffs_base__make_slice_u8(fBuffer, SK_WUFFS_CODEC_BUFFER_SIZE); |
| fIOBuffer.meta = iobuf.meta; |
| } |
| |
| const SkWuffsFrame* SkWuffsCodec::frame(int i) const { |
| if ((0 <= i) && (static_cast<size_t>(i) < fFrames.size())) { |
| return &fFrames[i]; |
| } |
| return nullptr; |
| } |
| |
| SkEncodedImageFormat SkWuffsCodec::onGetEncodedFormat() const { |
| return SkEncodedImageFormat::kGIF; |
| } |
| |
| SkCodec::Result SkWuffsCodec::onGetPixels(const SkImageInfo& dstInfo, |
| void* dst, |
| size_t rowBytes, |
| const Options& options, |
| int* rowsDecoded) { |
| SkCodec::Result result = this->onStartIncrementalDecode(dstInfo, dst, rowBytes, options); |
| if (result != kSuccess) { |
| return result; |
| } |
| return this->onIncrementalDecode(rowsDecoded); |
| } |
| |
| const SkFrameHolder* SkWuffsCodec::getFrameHolder() const { |
| return &fFrameHolder; |
| } |
| |
| SkCodec::Result SkWuffsCodec::onStartIncrementalDecode(const SkImageInfo& dstInfo, |
| void* dst, |
| size_t rowBytes, |
| const SkCodec::Options& options) { |
| if (!dst) { |
| return SkCodec::kInvalidParameters; |
| } |
| if (options.fSubset) { |
| return SkCodec::kUnimplemented; |
| } |
| SkCodec::Result result = this->seekFrame(options.fFrameIndex); |
| if (result != SkCodec::kSuccess) { |
| return result; |
| } |
| |
| const char* status = this->decodeFrameConfig(); |
| if (status == wuffs_base__suspension__short_read) { |
| return SkCodec::kIncompleteInput; |
| } else if (status != nullptr) { |
| SkCodecPrintf("decodeFrameConfig: %s", status); |
| return SkCodec::kErrorInInput; |
| } |
| |
| uint32_t pixelFormat = WUFFS_BASE__PIXEL_FORMAT__INVALID; |
| size_t bytesPerPixel = 0; |
| |
| switch (dstInfo.colorType()) { |
| case kRGB_565_SkColorType: |
| pixelFormat = WUFFS_BASE__PIXEL_FORMAT__BGR_565; |
| bytesPerPixel = 2; |
| break; |
| case kBGRA_8888_SkColorType: |
| pixelFormat = WUFFS_BASE__PIXEL_FORMAT__BGRA_NONPREMUL; |
| bytesPerPixel = 4; |
| break; |
| case kRGBA_8888_SkColorType: |
| pixelFormat = WUFFS_BASE__PIXEL_FORMAT__RGBA_NONPREMUL; |
| bytesPerPixel = 4; |
| break; |
| default: |
| break; |
| } |
| |
| // We can use "one pass" decoding if we have a Skia pixel format that Wuffs |
| // supports... |
| fIncrDecOnePass = (pixelFormat != WUFFS_BASE__PIXEL_FORMAT__INVALID) && |
| // ...and no color profile (as Wuffs does not support them)... |
| (!getEncodedInfo().profile()) && |
| // ...and we use the identity transform (as Wuffs does |
| // not support scaling). |
| (this->dimensions() == dstInfo.dimensions()); |
| |
| result = fIncrDecOnePass ? this->onStartIncrementalDecodeOnePass( |
| dstInfo, static_cast<uint8_t*>(dst), rowBytes, options, |
| pixelFormat, bytesPerPixel) |
| : this->onStartIncrementalDecodeTwoPass(); |
| if (result != SkCodec::kSuccess) { |
| return result; |
| } |
| |
| fIncrDecDst = static_cast<uint8_t*>(dst); |
| fIncrDecRowBytes = rowBytes; |
| fFirstCallToIncrementalDecode = true; |
| return SkCodec::kSuccess; |
| } |
| |
| SkCodec::Result SkWuffsCodec::onStartIncrementalDecodeOnePass(const SkImageInfo& dstInfo, |
| uint8_t* dst, |
| size_t rowBytes, |
| const SkCodec::Options& options, |
| uint32_t pixelFormat, |
| size_t bytesPerPixel) { |
| wuffs_base__pixel_config pixelConfig; |
| pixelConfig.set(pixelFormat, WUFFS_BASE__PIXEL_SUBSAMPLING__NONE, dstInfo.width(), |
| dstInfo.height()); |
| |
| wuffs_base__table_u8 table; |
| table.ptr = dst; |
| table.width = static_cast<size_t>(dstInfo.width()) * bytesPerPixel; |
| table.height = dstInfo.height(); |
| table.stride = rowBytes; |
| |
| wuffs_base__status status = fPixelBuffer.set_from_table(&pixelConfig, table); |
| if (status.repr != nullptr) { |
| SkCodecPrintf("set_from_table: %s", status.message()); |
| return SkCodec::kInternalError; |
| } |
| |
| // SRC is usually faster than SRC_OVER, but for a dependent frame, dst is |
| // assumed to hold the previous frame's pixels (after processing the |
| // DisposalMethod). For one-pass decoding, we therefore use SRC_OVER. |
| if ((options.fFrameIndex != 0) && |
| (this->frame(options.fFrameIndex)->getRequiredFrame() != SkCodec::kNoFrame)) { |
| fIncrDecPixelBlend = WUFFS_BASE__PIXEL_BLEND__SRC_OVER; |
| } else { |
| SkSampler::Fill(dstInfo, dst, rowBytes, options.fZeroInitialized); |
| fIncrDecPixelBlend = WUFFS_BASE__PIXEL_BLEND__SRC; |
| } |
| |
| return SkCodec::kSuccess; |
| } |
| |
| SkCodec::Result SkWuffsCodec::onStartIncrementalDecodeTwoPass() { |
| // Either re-use the previously allocated "two pass" pixel buffer (and |
| // memset to zero), or allocate (and zero initialize) a new one. |
| bool already_zeroed = false; |
| |
| if (!fTwoPassPixbufPtr) { |
| uint64_t pixbuf_len = fPixelConfig.pixbuf_len(); |
| void* pixbuf_ptr_raw = (pixbuf_len <= SIZE_MAX) |
| ? sk_malloc_flags(pixbuf_len, SK_MALLOC_ZERO_INITIALIZE) |
| : nullptr; |
| if (!pixbuf_ptr_raw) { |
| return SkCodec::kInternalError; |
| } |
| fTwoPassPixbufPtr.reset(reinterpret_cast<uint8_t*>(pixbuf_ptr_raw)); |
| fTwoPassPixbufLen = SkToSizeT(pixbuf_len); |
| already_zeroed = true; |
| } |
| |
| wuffs_base__status status = fPixelBuffer.set_from_slice( |
| &fPixelConfig, wuffs_base__make_slice_u8(fTwoPassPixbufPtr.get(), fTwoPassPixbufLen)); |
| if (status.repr != nullptr) { |
| SkCodecPrintf("set_from_slice: %s", status.message()); |
| return SkCodec::kInternalError; |
| } |
| |
| if (!already_zeroed) { |
| uint32_t src_bits_per_pixel = fPixelConfig.pixel_format().bits_per_pixel(); |
| if ((src_bits_per_pixel == 0) || (src_bits_per_pixel % 8 != 0)) { |
| return SkCodec::kInternalError; |
| } |
| size_t src_bytes_per_pixel = src_bits_per_pixel / 8; |
| |
| wuffs_base__rect_ie_u32 frame_rect = fFrameConfig.bounds(); |
| wuffs_base__table_u8 pixels = fPixelBuffer.plane(0); |
| |
| uint8_t* ptr = pixels.ptr + (frame_rect.min_incl_y * pixels.stride) + |
| (frame_rect.min_incl_x * src_bytes_per_pixel); |
| size_t len = frame_rect.width() * src_bytes_per_pixel; |
| |
| // As an optimization, issue a single sk_bzero call, if possible. |
| // Otherwise, zero out each row separately. |
| if ((len == pixels.stride) && (frame_rect.min_incl_y < frame_rect.max_excl_y)) { |
| sk_bzero(ptr, len * (frame_rect.max_excl_y - frame_rect.min_incl_y)); |
| } else { |
| for (uint32_t y = frame_rect.min_incl_y; y < frame_rect.max_excl_y; y++) { |
| sk_bzero(ptr, len); |
| ptr += pixels.stride; |
| } |
| } |
| } |
| |
| fIncrDecPixelBlend = WUFFS_BASE__PIXEL_BLEND__SRC; |
| return SkCodec::kSuccess; |
| } |
| |
| SkCodec::Result SkWuffsCodec::onIncrementalDecode(int* rowsDecoded) { |
| if (!fIncrDecDst) { |
| return SkCodec::kInternalError; |
| } |
| |
| if (rowsDecoded) { |
| *rowsDecoded = dstInfo().height(); |
| } |
| |
| SkCodec::Result result = |
| fIncrDecOnePass ? this->onIncrementalDecodeOnePass() : this->onIncrementalDecodeTwoPass(); |
| if (result == SkCodec::kSuccess) { |
| fIncrDecDst = nullptr; |
| fIncrDecRowBytes = 0; |
| fIncrDecPixelBlend = WUFFS_BASE__PIXEL_BLEND__SRC; |
| fIncrDecOnePass = false; |
| } |
| return result; |
| } |
| |
| SkCodec::Result SkWuffsCodec::onIncrementalDecodeOnePass() { |
| const char* status = this->decodeFrame(); |
| if (status != nullptr) { |
| if (status == wuffs_base__suspension__short_read) { |
| return SkCodec::kIncompleteInput; |
| } else { |
| SkCodecPrintf("decodeFrame: %s", status); |
| return SkCodec::kErrorInInput; |
| } |
| } |
| return SkCodec::kSuccess; |
| } |
| |
| SkCodec::Result SkWuffsCodec::onIncrementalDecodeTwoPass() { |
| SkCodec::Result result = SkCodec::kSuccess; |
| const char* status = this->decodeFrame(); |
| bool independent; |
| SkAlphaType alphaType; |
| const int index = options().fFrameIndex; |
| if (index == 0) { |
| independent = true; |
| alphaType = to_alpha_type(getEncodedInfo().opaque()); |
| } else { |
| const SkWuffsFrame* f = this->frame(index); |
| independent = f->getRequiredFrame() == SkCodec::kNoFrame; |
| alphaType = to_alpha_type(f->reportedAlpha() == SkEncodedInfo::kOpaque_Alpha); |
| } |
| if (status != nullptr) { |
| if (status == wuffs_base__suspension__short_read) { |
| result = SkCodec::kIncompleteInput; |
| } else { |
| SkCodecPrintf("decodeFrame: %s", status); |
| result = SkCodec::kErrorInInput; |
| } |
| |
| if (!independent) { |
| // For a dependent frame, we cannot blend the partial result, since |
| // that will overwrite the contribution from prior frames. |
| return result; |
| } |
| } |
| |
| uint32_t src_bits_per_pixel = fPixelBuffer.pixcfg.pixel_format().bits_per_pixel(); |
| if ((src_bits_per_pixel == 0) || (src_bits_per_pixel % 8 != 0)) { |
| return SkCodec::kInternalError; |
| } |
| size_t src_bytes_per_pixel = src_bits_per_pixel / 8; |
| |
| wuffs_base__rect_ie_u32 frame_rect = fFrameConfig.bounds(); |
| if (fFirstCallToIncrementalDecode) { |
| if (frame_rect.width() > (SIZE_MAX / src_bytes_per_pixel)) { |
| return SkCodec::kInternalError; |
| } |
| |
| auto bounds = SkIRect::MakeLTRB(frame_rect.min_incl_x, frame_rect.min_incl_y, |
| frame_rect.max_excl_x, frame_rect.max_excl_y); |
| |
| // If the frame rect does not fill the output, ensure that those pixels are not |
| // left uninitialized. |
| if (independent && (bounds != this->bounds() || result != kSuccess)) { |
| SkSampler::Fill(dstInfo(), fIncrDecDst, fIncrDecRowBytes, options().fZeroInitialized); |
| } |
| fFirstCallToIncrementalDecode = false; |
| } else { |
| // Existing clients intend to only show frames beyond the first if they |
| // are complete (based on FrameInfo::fFullyReceived), since it might |
| // look jarring to draw a partial frame over an existing frame. If they |
| // changed their behavior and expected to continue decoding a partial |
| // frame after the first one, we'll need to update our blending code. |
| // Otherwise, if the frame were interlaced and not independent, the |
| // second pass may have an overlapping dirty_rect with the first, |
| // resulting in blending with the first pass. |
| SkASSERT(index == 0); |
| } |
| |
| // If the frame's dirty rect is empty, no need to swizzle. |
| wuffs_base__rect_ie_u32 dirty_rect = fDecoder->frame_dirty_rect(); |
| if (!dirty_rect.is_empty()) { |
| wuffs_base__table_u8 pixels = fPixelBuffer.plane(0); |
| |
| // The Wuffs model is that the dst buffer is the image, not the frame. |
| // The expectation is that you allocate the buffer once, but re-use it |
| // for the N frames, regardless of each frame's top-left co-ordinate. |
| // |
| // To get from the start (in the X-direction) of the image to the start |
| // of the dirty_rect, we adjust s by (dirty_rect.min_incl_x * src_bytes_per_pixel). |
| uint8_t* s = pixels.ptr + (dirty_rect.min_incl_y * pixels.stride) + |
| (dirty_rect.min_incl_x * src_bytes_per_pixel); |
| |
| // Currently, this is only used for GIF, which will never have an ICC profile. When it is |
| // used for other formats that might have one, we will need to transform from profiles that |
| // do not have corresponding SkColorSpaces. |
| SkASSERT(!getEncodedInfo().profile()); |
| |
| auto srcInfo = |
| getInfo().makeWH(dirty_rect.width(), dirty_rect.height()).makeAlphaType(alphaType); |
| SkBitmap src; |
| src.installPixels(srcInfo, s, pixels.stride); |
| SkPaint paint; |
| if (independent) { |
| paint.setBlendMode(SkBlendMode::kSrc); |
| } |
| |
| SkDraw draw; |
| draw.fDst.reset(dstInfo(), fIncrDecDst, fIncrDecRowBytes); |
| SkMatrix matrix = SkMatrix::RectToRect(SkRect::Make(this->dimensions()), |
| SkRect::Make(this->dstInfo().dimensions())); |
| SkMatrixProvider matrixProvider(matrix); |
| draw.fMatrixProvider = &matrixProvider; |
| SkRasterClip rc(SkIRect::MakeSize(this->dstInfo().dimensions())); |
| draw.fRC = &rc; |
| |
| SkMatrix translate = SkMatrix::Translate(dirty_rect.min_incl_x, dirty_rect.min_incl_y); |
| draw.drawBitmap(src, translate, nullptr, SkSamplingOptions(), paint); |
| } |
| |
| if (result == SkCodec::kSuccess) { |
| // On success, we are done using the "two pass" pixel buffer for this |
| // frame. We have the option of releasing its memory, but there is a |
| // trade-off. If decoding a subsequent frame will also need "two pass" |
| // decoding, it would have to re-allocate the buffer instead of just |
| // re-using it. On the other hand, if there is no subsequent frame, and |
| // the SkWuffsCodec object isn't deleted soon, then we are holding |
| // megabytes of memory longer than we need to. |
| // |
| // For example, when the Chromium web browser decodes the <img> tags in |
| // a HTML page, the SkCodec object can live until navigating away from |
| // the page, which can be much longer than when the pixels are fully |
| // decoded, especially for a still (non-animated) image. Even for |
| // looping animations, caching the decoded frames (at the higher HTML |
| // renderer layer) may mean that each frame is only decoded once (at |
| // the lower SkCodec layer), in sequence. |
| // |
| // The heuristic we use here is to free the memory if we have decoded |
| // the last frame of the animation (or, for still images, the only |
| // frame). The output of the next decode request (if any) should be the |
| // same either way, but the steady state memory use should hopefully be |
| // lower than always keeping the fTwoPassPixbufPtr buffer up until the |
| // SkWuffsCodec destructor runs. |
| // |
| // This only applies to "two pass" decoding. "One pass" decoding does |
| // not allocate, free or otherwise use fTwoPassPixbufPtr. |
| if (fFramesComplete && (static_cast<size_t>(options().fFrameIndex) == fFrames.size() - 1)) { |
| fTwoPassPixbufPtr.reset(nullptr); |
| fTwoPassPixbufLen = 0; |
| } |
| } |
| |
| return result; |
| } |
| |
| int SkWuffsCodec::onGetFrameCount() { |
| // It is valid, in terms of the SkCodec API, to call SkCodec::getFrameCount |
| // while in an incremental decode (after onStartIncrementalDecode returns |
| // and before onIncrementalDecode returns kSuccess). |
| // |
| // We should not advance the SkWuffsCodec' stream while doing so, even |
| // though other SkCodec implementations can return increasing values from |
| // onGetFrameCount when given more data. If we tried to do so, the |
| // subsequent resume of the incremental decode would continue reading from |
| // a different position in the I/O stream, leading to an incorrect error. |
| // |
| // Other SkCodec implementations can move the stream forward during |
| // onGetFrameCount because they assume that the stream is rewindable / |
| // seekable. For example, an alternative GIF implementation may choose to |
| // store, for each frame walked past when merely counting the number of |
| // frames, the I/O position of each of the frame's GIF data blocks. (A GIF |
| // frame's compressed data can have multiple data blocks, each at most 255 |
| // bytes in length). Obviously, this can require O(numberOfFrames) extra |
| // memory to store these I/O positions. The constant factor is small, but |
| // it's still O(N), not O(1). |
| // |
| // Wuffs and SkWuffsCodec try to minimize relying on the rewindable / |
| // seekable assumption. By design, Wuffs per se aims for O(1) memory use |
| // (after any pixel buffers are allocated) instead of O(N), and its I/O |
| // type, wuffs_base__io_buffer, is not necessarily rewindable or seekable. |
| // |
| // The Wuffs API provides a limited, optional form of seeking, to the start |
| // of an animation frame's data, but does not provide arbitrary save and |
| // load of its internal state whilst in the middle of an animation frame. |
| bool incrementalDecodeIsInProgress = fIncrDecDst != nullptr; |
| |
| if (!fFramesComplete && !incrementalDecodeIsInProgress) { |
| this->onGetFrameCountInternal(); |
| this->updateNumFullyReceivedFrames(); |
| } |
| return fFrames.size(); |
| } |
| |
| void SkWuffsCodec::onGetFrameCountInternal() { |
| size_t n = fFrames.size(); |
| int i = n ? n - 1 : 0; |
| if (this->seekFrame(i) != SkCodec::kSuccess) { |
| return; |
| } |
| |
| // Iterate through the frames, converting from Wuffs' |
| // wuffs_base__frame_config type to Skia's SkWuffsFrame type. |
| for (; i < INT_MAX; i++) { |
| const char* status = this->decodeFrameConfig(); |
| if (status == nullptr) { |
| // No-op. |
| } else if (status == wuffs_base__note__end_of_data) { |
| break; |
| } else { |
| return; |
| } |
| |
| if (static_cast<size_t>(i) < fFrames.size()) { |
| continue; |
| } |
| fFrames.emplace_back(&fFrameConfig); |
| SkWuffsFrame* f = &fFrames[fFrames.size() - 1]; |
| fFrameHolder.setAlphaAndRequiredFrame(f); |
| } |
| |
| fFramesComplete = true; |
| } |
| |
| bool SkWuffsCodec::onGetFrameInfo(int i, SkCodec::FrameInfo* frameInfo) const { |
| const SkWuffsFrame* f = this->frame(i); |
| if (!f) { |
| return false; |
| } |
| if (frameInfo) { |
| f->fillIn(frameInfo, static_cast<uint64_t>(i) < this->fNumFullyReceivedFrames); |
| } |
| return true; |
| } |
| |
| int SkWuffsCodec::onGetRepetitionCount() { |
| // Convert from Wuffs's loop count to Skia's repeat count. Wuffs' uint32_t |
| // number is how many times to play the loop. Skia's int number is how many |
| // times to play the loop *after the first play*. Wuffs and Skia use 0 and |
| // kRepetitionCountInfinite respectively to mean loop forever. |
| uint32_t n = fDecoder->num_animation_loops(); |
| if (n == 0) { |
| return SkCodec::kRepetitionCountInfinite; |
| } |
| n--; |
| return n < INT_MAX ? n : INT_MAX; |
| } |
| |
| SkCodec::Result SkWuffsCodec::seekFrame(int frameIndex) { |
| if (fDecoderIsSuspended) { |
| SkCodec::Result res = this->resetDecoder(); |
| if (res != SkCodec::kSuccess) { |
| return res; |
| } |
| } |
| |
| uint64_t pos = 0; |
| if (frameIndex < 0) { |
| return SkCodec::kInternalError; |
| } else if (frameIndex == 0) { |
| pos = fFirstFrameIOPosition; |
| } else if (static_cast<size_t>(frameIndex) < fFrames.size()) { |
| pos = fFrames[frameIndex].ioPosition(); |
| } else { |
| return SkCodec::kInternalError; |
| } |
| |
| if (!seek_buffer(&fIOBuffer, fStream.get(), pos)) { |
| return SkCodec::kInternalError; |
| } |
| wuffs_base__status status = |
| fDecoder->restart_frame(frameIndex, fIOBuffer.reader_io_position()); |
| if (status.repr != nullptr) { |
| return SkCodec::kInternalError; |
| } |
| return SkCodec::kSuccess; |
| } |
| |
| SkCodec::Result SkWuffsCodec::resetDecoder() { |
| if (!fStream->rewind()) { |
| return SkCodec::kInternalError; |
| } |
| fIOBuffer.meta = wuffs_base__empty_io_buffer_meta(); |
| |
| SkCodec::Result result = |
| reset_and_decode_image_config(fDecoder.get(), nullptr, &fIOBuffer, fStream.get()); |
| if (result == SkCodec::kIncompleteInput) { |
| return SkCodec::kInternalError; |
| } else if (result != SkCodec::kSuccess) { |
| return result; |
| } |
| |
| fDecoderIsSuspended = false; |
| return SkCodec::kSuccess; |
| } |
| |
| const char* SkWuffsCodec::decodeFrameConfig() { |
| while (true) { |
| wuffs_base__status status = |
| fDecoder->decode_frame_config(&fFrameConfig, &fIOBuffer); |
| if ((status.repr == wuffs_base__suspension__short_read) && |
| fill_buffer(&fIOBuffer, fStream.get())) { |
| continue; |
| } |
| fDecoderIsSuspended = !status.is_complete(); |
| this->updateNumFullyReceivedFrames(); |
| return status.repr; |
| } |
| } |
| |
| const char* SkWuffsCodec::decodeFrame() { |
| while (true) { |
| wuffs_base__status status = fDecoder->decode_frame( |
| &fPixelBuffer, &fIOBuffer, fIncrDecPixelBlend, |
| wuffs_base__make_slice_u8(fWorkbufPtr.get(), fWorkbufLen), nullptr); |
| if ((status.repr == wuffs_base__suspension__short_read) && |
| fill_buffer(&fIOBuffer, fStream.get())) { |
| continue; |
| } |
| fDecoderIsSuspended = !status.is_complete(); |
| this->updateNumFullyReceivedFrames(); |
| return status.repr; |
| } |
| } |
| |
| void SkWuffsCodec::updateNumFullyReceivedFrames() { |
| // num_decoded_frames's return value, n, can change over time, both up and |
| // down, as we seek back and forth in the underlying stream. |
| // fNumFullyReceivedFrames is the highest n we've seen. |
| uint64_t n = fDecoder->num_decoded_frames(); |
| if (fNumFullyReceivedFrames < n) { |
| fNumFullyReceivedFrames = n; |
| } |
| } |
| |
| // -------------------------------- SkWuffsCodec.h functions |
| |
| bool SkWuffsCodec_IsFormat(const void* buf, size_t bytesRead) { |
| constexpr const char* gif_ptr = "GIF8"; |
| constexpr size_t gif_len = 4; |
| return (bytesRead >= gif_len) && (memcmp(buf, gif_ptr, gif_len) == 0); |
| } |
| |
| std::unique_ptr<SkCodec> SkWuffsCodec_MakeFromStream(std::unique_ptr<SkStream> stream, |
| SkCodec::Result* result) { |
| // Some clients (e.g. Android) need to be able to seek the stream, but may |
| // not provide a seekable stream. Copy the stream to one that can seek. |
| if (!stream->hasPosition() || !stream->hasLength()) { |
| auto data = SkCopyStreamToData(stream.get()); |
| stream = std::make_unique<SkMemoryStream>(std::move(data)); |
| } |
| |
| uint8_t buffer[SK_WUFFS_CODEC_BUFFER_SIZE]; |
| wuffs_base__io_buffer iobuf = |
| wuffs_base__make_io_buffer(wuffs_base__make_slice_u8(buffer, SK_WUFFS_CODEC_BUFFER_SIZE), |
| wuffs_base__empty_io_buffer_meta()); |
| wuffs_base__image_config imgcfg = wuffs_base__null_image_config(); |
| |
| // Wuffs is primarily a C library, not a C++ one. Furthermore, outside of |
| // the wuffs_base__etc types, the sizeof a file format specific type like |
| // GIF's wuffs_gif__decoder can vary between Wuffs versions. If p is of |
| // type wuffs_gif__decoder*, then the supported API treats p as a pointer |
| // to an opaque type: a private implementation detail. The API is always |
| // "set_foo(p, etc)" and not "p->foo = etc". |
| // |
| // See https://en.wikipedia.org/wiki/Opaque_pointer#C |
| // |
| // Thus, we don't use C++'s new operator (which requires knowing the sizeof |
| // the struct at compile time). Instead, we use sk_malloc_canfail, with |
| // sizeof__wuffs_gif__decoder returning the appropriate value for the |
| // (statically or dynamically) linked version of the Wuffs library. |
| // |
| // As a C (not C++) library, none of the Wuffs types have constructors or |
| // destructors. |
| // |
| // In RAII style, we can still use std::unique_ptr with these pointers, but |
| // we pair the pointer with sk_free instead of C++'s delete. |
| void* decoder_raw = sk_malloc_canfail(sizeof__wuffs_gif__decoder()); |
| if (!decoder_raw) { |
| *result = SkCodec::kInternalError; |
| return nullptr; |
| } |
| std::unique_ptr<wuffs_gif__decoder, decltype(&sk_free)> decoder( |
| reinterpret_cast<wuffs_gif__decoder*>(decoder_raw), &sk_free); |
| |
| SkCodec::Result reset_result = |
| reset_and_decode_image_config(decoder.get(), &imgcfg, &iobuf, stream.get()); |
| if (reset_result != SkCodec::kSuccess) { |
| *result = reset_result; |
| return nullptr; |
| } |
| |
| uint32_t width = imgcfg.pixcfg.width(); |
| uint32_t height = imgcfg.pixcfg.height(); |
| if ((width == 0) || (width > INT_MAX) || (height == 0) || (height > INT_MAX)) { |
| *result = SkCodec::kInvalidInput; |
| return nullptr; |
| } |
| |
| uint64_t workbuf_len = decoder->workbuf_len().max_incl; |
| void* workbuf_ptr_raw = nullptr; |
| if (workbuf_len) { |
| workbuf_ptr_raw = workbuf_len <= SIZE_MAX ? sk_malloc_canfail(workbuf_len) : nullptr; |
| if (!workbuf_ptr_raw) { |
| *result = SkCodec::kInternalError; |
| return nullptr; |
| } |
| } |
| std::unique_ptr<uint8_t, decltype(&sk_free)> workbuf_ptr( |
| reinterpret_cast<uint8_t*>(workbuf_ptr_raw), &sk_free); |
| |
| SkEncodedInfo::Color color = |
| (imgcfg.pixcfg.pixel_format().repr == WUFFS_BASE__PIXEL_FORMAT__BGRA_NONPREMUL) |
| ? SkEncodedInfo::kBGRA_Color |
| : SkEncodedInfo::kRGBA_Color; |
| |
| // In Skia's API, the alpha we calculate here and return is only for the |
| // first frame. |
| SkEncodedInfo::Alpha alpha = imgcfg.first_frame_is_opaque() ? SkEncodedInfo::kOpaque_Alpha |
| : SkEncodedInfo::kBinary_Alpha; |
| |
| SkEncodedInfo encodedInfo = SkEncodedInfo::Make(width, height, color, alpha, 8); |
| |
| *result = SkCodec::kSuccess; |
| return std::unique_ptr<SkCodec>(new SkWuffsCodec(std::move(encodedInfo), std::move(stream), |
| std::move(decoder), std::move(workbuf_ptr), |
| workbuf_len, imgcfg, iobuf)); |
| } |