Revert "Add Animated PNG demuxer (#31098)" This reverts commit b3e9642c6b37943db65ea768e819662b45feb09f.
diff --git a/ci/licenses_golden/licenses_flutter b/ci/licenses_golden/licenses_flutter index d2468df..3f9b72a 100644 --- a/ci/licenses_golden/licenses_flutter +++ b/ci/licenses_golden/licenses_flutter
@@ -1789,8 +1789,6 @@ ORIGIN: ../../../flutter/lib/ui/painting/image_filter.h + ../../../flutter/LICENSE ORIGIN: ../../../flutter/lib/ui/painting/image_generator.cc + ../../../flutter/LICENSE ORIGIN: ../../../flutter/lib/ui/painting/image_generator.h + ../../../flutter/LICENSE -ORIGIN: ../../../flutter/lib/ui/painting/image_generator_apng.cc + ../../../flutter/LICENSE -ORIGIN: ../../../flutter/lib/ui/painting/image_generator_apng.h + ../../../flutter/LICENSE ORIGIN: ../../../flutter/lib/ui/painting/image_generator_registry.cc + ../../../flutter/LICENSE ORIGIN: ../../../flutter/lib/ui/painting/image_generator_registry.h + ../../../flutter/LICENSE ORIGIN: ../../../flutter/lib/ui/painting/image_shader.cc + ../../../flutter/LICENSE @@ -4268,8 +4266,6 @@ FILE: ../../../flutter/lib/ui/painting/image_filter.h FILE: ../../../flutter/lib/ui/painting/image_generator.cc FILE: ../../../flutter/lib/ui/painting/image_generator.h -FILE: ../../../flutter/lib/ui/painting/image_generator_apng.cc -FILE: ../../../flutter/lib/ui/painting/image_generator_apng.h FILE: ../../../flutter/lib/ui/painting/image_generator_registry.cc FILE: ../../../flutter/lib/ui/painting/image_generator_registry.h FILE: ../../../flutter/lib/ui/painting/image_shader.cc
diff --git a/fml/endianness.h b/fml/endianness.h index eff90f9..269b461 100644 --- a/fml/endianness.h +++ b/fml/endianness.h
@@ -26,17 +26,9 @@ namespace fml { -template <typename T> -struct IsByteSwappable - : public std:: - integral_constant<bool, std::is_integral_v<T> || std::is_enum_v<T>> { -}; -template <typename T> -constexpr bool IsByteSwappableV = IsByteSwappable<T>::value; - /// @brief Flips the endianness of the given value. /// The given value must be an integral type of size 1, 2, 4, or 8. -template <typename T, class = std::enable_if_t<IsByteSwappableV<T>>> +template <typename T, class = std::enable_if_t<std::is_integral_v<T>>> constexpr T ByteSwap(T n) { if constexpr (sizeof(T) == 1) { return n; @@ -55,7 +47,7 @@ /// current architecture. This is effectively a cross platform /// ntohl/ntohs (as network byte order is always Big Endian). /// The given value must be an integral type of size 1, 2, 4, or 8. -template <typename T, class = std::enable_if_t<IsByteSwappableV<T>>> +template <typename T, class = std::enable_if_t<std::is_integral_v<T>>> constexpr T BigEndianToArch(T n) { #if FML_ARCH_CPU_LITTLE_ENDIAN return ByteSwap<T>(n); @@ -67,7 +59,7 @@ /// @brief Convert a known little endian value to match the endianness of the /// current architecture. /// The given value must be an integral type of size 1, 2, 4, or 8. -template <typename T, class = std::enable_if_t<IsByteSwappableV<T>>> +template <typename T, class = std::enable_if_t<std::is_integral_v<T>>> constexpr T LittleEndianToArch(T n) { #if !FML_ARCH_CPU_LITTLE_ENDIAN return ByteSwap<T>(n);
diff --git a/lib/ui/BUILD.gn b/lib/ui/BUILD.gn index b0c3ce3..02a6fab 100644 --- a/lib/ui/BUILD.gn +++ b/lib/ui/BUILD.gn
@@ -59,8 +59,6 @@ "painting/image_filter.h", "painting/image_generator.cc", "painting/image_generator.h", - "painting/image_generator_apng.cc", - "painting/image_generator_apng.h", "painting/image_generator_registry.cc", "painting/image_generator_registry.h", "painting/image_shader.cc", @@ -163,7 +161,6 @@ "//third_party/dart/runtime/bin:dart_io_api", "//third_party/rapidjson", "//third_party/skia", - "//third_party/zlib:zlib", ] if (impeller_supports_rendering) {
diff --git a/lib/ui/painting/image_decoder_unittests.cc b/lib/ui/painting/image_decoder_unittests.cc index a9b09c5..2bf4a8b 100644 --- a/lib/ui/painting/image_decoder_unittests.cc +++ b/lib/ui/painting/image_decoder_unittests.cc
@@ -162,7 +162,7 @@ unsigned int GetPlayCount() const { return 1; } - const ImageGenerator::FrameInfo GetFrameInfo(unsigned int frame_index) { + const ImageGenerator::FrameInfo GetFrameInfo(unsigned int frame_index) const { return {std::nullopt, 0, SkCodecAnimation::DisposalMethod::kKeep}; }
diff --git a/lib/ui/painting/image_generator.cc b/lib/ui/painting/image_generator.cc index 3db7625..e5648fc 100644 --- a/lib/ui/painting/image_generator.cc +++ b/lib/ui/painting/image_generator.cc
@@ -51,7 +51,7 @@ } const ImageGenerator::FrameInfo BuiltinSkiaImageGenerator::GetFrameInfo( - unsigned int frame_index) { + unsigned int frame_index) const { return {.required_frame = std::nullopt, .duration = 0, .disposal_method = SkCodecAnimation::DisposalMethod::kKeep}; @@ -105,7 +105,7 @@ } const ImageGenerator::FrameInfo BuiltinSkiaCodecImageGenerator::GetFrameInfo( - unsigned int frame_index) { + unsigned int frame_index) const { SkCodec::FrameInfo info = {}; codec_generator_->getFrameInfo(frame_index, &info); return {
diff --git a/lib/ui/painting/image_generator.h b/lib/ui/painting/image_generator.h index a5515c8..4792f3b 100644 --- a/lib/ui/painting/image_generator.h +++ b/lib/ui/painting/image_generator.h
@@ -37,15 +37,11 @@ /// blended with. std::optional<unsigned int> required_frame; - /// Number of milliseconds to show this frame. 0 means only show it for one - /// frame. + /// Number of milliseconds to show this frame. unsigned int duration; /// How this frame should be modified before decoding the next one. SkCodecAnimation::DisposalMethod disposal_method; - - /// How this frame should be blended with the previous frame. - SkCodecAnimation::Blend blend_mode; }; virtual ~ImageGenerator(); @@ -84,7 +80,7 @@ /// @return Information about the given frame. If the image is /// single-frame, a default result is returned. /// @see `GetFrameCount` - virtual const FrameInfo GetFrameInfo(unsigned int frame_index) = 0; + virtual const FrameInfo GetFrameInfo(unsigned int frame_index) const = 0; /// @brief Given a scale value, find the closest image size that can be /// used for efficiently decoding the image. If subpixel image @@ -156,7 +152,7 @@ // |ImageGenerator| const ImageGenerator::FrameInfo GetFrameInfo( - unsigned int frame_index) override; + unsigned int frame_index) const override; // |ImageGenerator| SkISize GetScaledDimensions(float desired_scale) override; @@ -196,7 +192,7 @@ // |ImageGenerator| const ImageGenerator::FrameInfo GetFrameInfo( - unsigned int frame_index) override; + unsigned int frame_index) const override; // |ImageGenerator| SkISize GetScaledDimensions(float desired_scale) override;
diff --git a/lib/ui/painting/image_generator_apng.cc b/lib/ui/painting/image_generator_apng.cc deleted file mode 100644 index 943d775..0000000 --- a/lib/ui/painting/image_generator_apng.cc +++ /dev/null
@@ -1,616 +0,0 @@ -// Copyright 2013 The Flutter Authors. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be -// found in the LICENSE file. - -#include "image_generator_apng.h" -#include <cstddef> -#include <cstring> - -#include "flutter/fml/logging.h" -#include "third_party/libpng/png.h" -#include "third_party/skia/include/codec/SkCodecAnimation.h" -#include "third_party/skia/include/core/SkAlphaType.h" -#include "third_party/skia/include/core/SkColorType.h" -#include "third_party/skia/include/core/SkStream.h" -#include "third_party/skia/src/codec/SkPngCodec.h" -#include "third_party/zlib/zlib.h" // For crc32 - -namespace flutter { - -APNGImageGenerator::~APNGImageGenerator() = default; - -APNGImageGenerator::APNGImageGenerator(sk_sp<SkData>& data, - SkImageInfo& image_info, - APNGImage&& default_image, - unsigned int frame_count, - unsigned int play_count, - const void* next_chunk_p, - const std::vector<uint8_t>& header) - : data_(data), - image_info_(image_info), - frame_count_(frame_count), - play_count_(play_count), - first_frame_index_(default_image.frame_info.has_value() ? 0 : 1), - next_chunk_p_(next_chunk_p), - header_(header) { - images_.push_back(std::move(default_image)); -} - -const SkImageInfo& APNGImageGenerator::GetInfo() { - return image_info_; -} - -unsigned int APNGImageGenerator::GetFrameCount() const { - return frame_count_; -} - -unsigned int APNGImageGenerator::GetPlayCount() const { - return frame_count_ > 1 ? play_count_ : 1; -} - -const ImageGenerator::FrameInfo APNGImageGenerator::GetFrameInfo( - unsigned int frame_index) { - unsigned int image_index = first_frame_index_ + frame_index; - if (!DemuxToImageIndex(image_index)) { - return {}; - } - - return images_[image_index].frame_info.value(); -} - -SkISize APNGImageGenerator::GetScaledDimensions(float desired_scale) { - return image_info_.dimensions(); -} - -bool APNGImageGenerator::GetPixels(const SkImageInfo& info, - void* pixels, - size_t row_bytes, - unsigned int frame_index, - std::optional<unsigned int> prior_frame) { - FML_DCHECK(images_.size() > 0); - unsigned int image_index = first_frame_index_ + frame_index; - - //---------------------------------------------------------------------------- - /// 1. Demux the frame from the APNG stream. - /// - - if (!DemuxToImageIndex(image_index)) { - FML_DLOG(ERROR) << "Couldn't demux image at index " << image_index - << " (frame index: " << frame_index - << ") from APNG stream."; - return RenderDefaultImage(info, pixels, row_bytes); - } - - //---------------------------------------------------------------------------- - /// 2. Decode the frame. - /// - - APNGImage& frame = images_[image_index]; - auto frame_info = frame.codec->getInfo(); - auto frame_row_bytes = frame_info.bytesPerPixel() * frame_info.width(); - - if (frame.pixels.empty()) { - frame.pixels.resize(frame_row_bytes * frame_info.height()); - SkCodec::Result result = frame.codec->getPixels( - frame.codec->getInfo(), frame.pixels.data(), frame_row_bytes); - if (result != SkCodec::kSuccess) { - FML_DLOG(ERROR) << "Failed to decode image at index " << image_index - << " (frame index: " << frame_index - << ") of APNG. SkCodec::Result: " << result; - return RenderDefaultImage(info, pixels, row_bytes); - } - } - - //---------------------------------------------------------------------------- - /// 3. Composite the frame onto the canvas. - /// - - if (info.colorType() != kN32_SkColorType) { - FML_DLOG(ERROR) << "Failed to composite image at index " << image_index - << " (frame index: " << frame_index - << ") of APNG due to the destination surface having an " - "unsupported color type."; - return false; - } - if (frame_info.colorType() != kN32_SkColorType) { - FML_DLOG(ERROR) - << "Failed to composite image at index " << image_index - << " (frame index: " << frame_index - << ") of APNG due to the frame having an unsupported color type."; - return false; - } - - // Regardless of the byte order (RGBA vs BGRA), the blending operations are - // the same. - struct Pixel { - uint8_t channel[4]; - - uint8_t GetAlpha() { return channel[3]; } - - void Premultiply() { - for (int i = 0; i < 3; i++) { - channel[i] = channel[i] * GetAlpha() / 0xFF; - } - } - - void Unpremultiply() { - if (GetAlpha() == 0) { - channel[0] = channel[1] = channel[2] = 0; - return; - } - for (int i = 0; i < 3; i++) { - channel[i] = channel[i] * 0xFF / GetAlpha(); - } - } - }; - - FML_DCHECK(frame_info.bytesPerPixel() == sizeof(Pixel)); - - for (int y = 0; y < frame_info.height(); y++) { - auto src_row = frame.pixels.data() + y * frame_row_bytes; - auto dst_row = static_cast<uint8_t*>(pixels) + - (y + frame.y_offset) * row_bytes + - frame.x_offset * frame_info.bytesPerPixel(); - - switch (frame.frame_info->blend_mode) { - case SkCodecAnimation::Blend::kSrcOver: { - for (int x = 0; x < frame_info.width(); x++) { - auto x_offset_bytes = x * frame_info.bytesPerPixel(); - - Pixel src = *reinterpret_cast<Pixel*>(src_row + x_offset_bytes); - Pixel* dst_p = reinterpret_cast<Pixel*>(dst_row + x_offset_bytes); - Pixel dst = *dst_p; - - // Ensure both colors are premultiplied for the blending operation. - if (info.alphaType() == kUnpremul_SkAlphaType) { - dst.Premultiply(); - } - if (frame_info.alphaType() == kUnpremul_SkAlphaType) { - src.Premultiply(); - } - - for (int i = 0; i < 4; i++) { - dst.channel[i] = src.channel[i] + - dst.channel[i] * (0xFF - src.GetAlpha()) / 0xFF; - } - - // The final color is premultiplied. Unpremultiply to match the - // backdrop surface if necessary. - if (info.alphaType() == kUnpremul_SkAlphaType) { - dst.Unpremultiply(); - } - - *dst_p = dst; - } - break; - } - case SkCodecAnimation::Blend::kSrc: - memcpy(dst_row, src_row, frame_row_bytes); - break; - } - } - - return true; -} - -std::unique_ptr<ImageGenerator> APNGImageGenerator::MakeFromData( - sk_sp<SkData> data) { - // Ensure the buffer is large enough to at least contain the PNG signature - // and a chunk header. - if (data->size() < sizeof(kPngSignature) + sizeof(ChunkHeader)) { - return nullptr; - } - // Validate the full PNG signature. - const uint8_t* data_p = static_cast<const uint8_t*>(data.get()->data()); - if (png_sig_cmp(static_cast<png_const_bytep>(data_p), 0, - sizeof(kPngSignature))) { - return nullptr; - } - - // Validate the header chunk. - const ChunkHeader* chunk = reinterpret_cast<const ChunkHeader*>(data_p + 8); - if (!IsValidChunkHeader(data_p, data->size(), chunk) || - chunk->get_data_length() != sizeof(ImageHeaderChunkData) || - chunk->get_type() != kImageHeaderChunkType) { - return nullptr; - } - - // Walk the chunks to find the "animation control" chunk. If an "image data" - // chunk is found first, this PNG is not animated. - while (true) { - chunk = GetNextChunk(data_p, data->size(), chunk); - - if (chunk == nullptr) { - return nullptr; - } - if (chunk->get_type() == kImageDataChunkType) { - return nullptr; - } - if (chunk->get_type() == kAnimationControlChunkType) { - break; - } - } - - const AnimationControlChunkData* animation_data = - CastChunkData<AnimationControlChunkData>(chunk); - - // Extract the header signature and chunks to prepend when demuxing images. - std::optional<std::vector<uint8_t>> header; - const void* first_chunk_p; - std::tie(header, first_chunk_p) = ExtractHeader(data_p, data->size()); - if (!header.has_value()) { - return nullptr; - } - - // Demux the first image in the APNG chunk stream in order to interpret - // extent and blending info immediately. - std::optional<APNGImage> default_image; - const void* next_chunk_p; - std::tie(default_image, next_chunk_p) = - DemuxNextImage(data_p, data->size(), header.value(), first_chunk_p); - if (!default_image.has_value()) { - return nullptr; - } - - unsigned int play_count = animation_data->get_num_plays(); - if (play_count == 0) { - play_count = kInfinitePlayCount; - } - - SkImageInfo image_info = default_image.value().codec->getInfo(); - return std::unique_ptr<APNGImageGenerator>( - new APNGImageGenerator(data, image_info, std::move(default_image.value()), - animation_data->get_num_frames(), play_count, - next_chunk_p, header.value())); -} - -bool APNGImageGenerator::IsValidChunkHeader(const void* buffer, - size_t size, - const ChunkHeader* chunk) { - // Ensure the chunk doesn't start before the beginning of the buffer. - if (reinterpret_cast<const uint8_t*>(chunk) < - static_cast<const uint8_t*>(buffer)) { - return false; - } - - // Ensure the buffer is large enough to contain at least the chunk header. - if (reinterpret_cast<const uint8_t*>(chunk) + sizeof(ChunkHeader) > - static_cast<const uint8_t*>(buffer) + size) { - return false; - } - - // Ensure the buffer is large enough to contain the chunk's given data size - // and CRC. - const uint8_t* chunk_end = - reinterpret_cast<const uint8_t*>(chunk) + GetChunkSize(chunk); - if (chunk_end > static_cast<const uint8_t*>(buffer) + size) { - return false; - } - - // Ensure the 4-byte type only contains ISO 646 letters. - uint32_t type = chunk->get_type(); - for (int i = 0; i < 4; i++) { - uint8_t c = type >> i * 8 & 0xFF; - if (!((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z'))) { - return false; - } - } - - return true; -} - -const APNGImageGenerator::ChunkHeader* APNGImageGenerator::GetNextChunk( - const void* buffer, - size_t size, - const ChunkHeader* current_chunk) { - FML_DCHECK((uint8_t*)current_chunk + sizeof(ChunkHeader) <= - (uint8_t*)buffer + size); - - const ChunkHeader* next_chunk = reinterpret_cast<const ChunkHeader*>( - reinterpret_cast<const uint8_t*>(current_chunk) + - GetChunkSize(current_chunk)); - if (!IsValidChunkHeader(buffer, size, next_chunk)) { - return nullptr; - } - - return next_chunk; -} - -std::pair<std::optional<std::vector<uint8_t>>, const void*> -APNGImageGenerator::ExtractHeader(const void* buffer_p, size_t buffer_size) { - std::vector<uint8_t> result(sizeof(kPngSignature)); - memcpy(result.data(), kPngSignature, sizeof(kPngSignature)); - - const ChunkHeader* chunk = reinterpret_cast<const ChunkHeader*>( - static_cast<const uint8_t*>(buffer_p) + sizeof(kPngSignature)); - // Validate the first chunk to ensure it's safe to read. - if (!IsValidChunkHeader(buffer_p, buffer_size, chunk)) { - return std::make_pair(std::nullopt, nullptr); - } - - // Walk the chunks and copy in the non-APNG chunks until we come across a - // frame or image chunk. - do { - if (chunk->get_type() != kAnimationControlChunkType) { - size_t chunk_size = GetChunkSize(chunk); - result.resize(result.size() + chunk_size); - memcpy(result.data() + result.size() - chunk_size, chunk, chunk_size); - } - - chunk = GetNextChunk(buffer_p, buffer_size, chunk); - } while (chunk != nullptr && chunk->get_type() != kFrameControlChunkType && - chunk->get_type() != kImageDataChunkType && - chunk->get_type() != kFrameDataChunkType); - - // nullptr means the end of the buffer was reached, which means there's no - // frame or image data, so just return nothing because the PNG isn't even - // valid. - if (chunk == nullptr) { - return std::make_pair(std::nullopt, nullptr); - } - - return std::make_pair(result, chunk); -} - -std::pair<std::optional<APNGImageGenerator::APNGImage>, const void*> -APNGImageGenerator::DemuxNextImage(const void* buffer_p, - size_t buffer_size, - const std::vector<uint8_t>& header, - const void* chunk_p) { - const ChunkHeader* chunk = reinterpret_cast<const ChunkHeader*>(chunk_p); - // Validate the given chunk to ensure it's safe to read. - if (!IsValidChunkHeader(buffer_p, buffer_size, chunk)) { - return std::make_pair(std::nullopt, nullptr); - } - - // Expect frame data to begin at fdAT or IDAT - if (chunk->get_type() != kFrameControlChunkType && - chunk->get_type() != kImageDataChunkType) { - return std::make_pair(std::nullopt, nullptr); - } - - APNGImage result; - const FrameControlChunkData* control_data = nullptr; - - // The presence of an fcTL chunk is optional for the first (default) image - // of a PNG. Both cases are handled in APNGImage. - if (chunk->get_type() == kFrameControlChunkType) { - control_data = CastChunkData<FrameControlChunkData>(chunk); - - ImageGenerator::FrameInfo frame_info; - switch (control_data->get_blend_op()) { - case 0: // APNG_BLEND_OP_SOURCE - frame_info.blend_mode = SkCodecAnimation::Blend::kSrc; - break; - case 1: // APNG_BLEND_OP_OVER - frame_info.blend_mode = SkCodecAnimation::Blend::kSrcOver; - break; - default: - return std::make_pair(std::nullopt, nullptr); - } - switch (control_data->get_dispose_op()) { - case 0: // APNG_DISPOSE_OP_NONE - frame_info.disposal_method = SkCodecAnimation::DisposalMethod::kKeep; - break; - case 1: // APNG_DISPOSE_OP_BACKGROUND - frame_info.disposal_method = - SkCodecAnimation::DisposalMethod::kRestoreBGColor; - break; - case 2: // APNG_DISPOSE_OP_PREVIOUS - frame_info.disposal_method = - SkCodecAnimation::DisposalMethod::kRestorePrevious; - break; - default: - return std::make_pair(std::nullopt, nullptr); - } - uint16_t denominator = control_data->get_delay_den() == 0 - ? 100 - : control_data->get_delay_den(); - frame_info.duration = - static_cast<int>(control_data->get_delay_num() * 1000.f / denominator); - - result.frame_info = frame_info; - result.x_offset = control_data->get_x_offset(); - result.y_offset = control_data->get_y_offset(); - } - - std::vector<const ChunkHeader*> image_chunks; - size_t chunk_space = 0; - - // Walk the chunks until the next frame, end chunk, or an invalid chunk is - // reached, recording the chunks to copy along with their required space. - // TODO(bdero): Validate that IDAT/fdAT chunks are contiguous. - // TODO(bdero): Validate the acTL/fcTL/fdAT sequence number ordering. - do { - if (chunk->get_type() != kFrameControlChunkType) { - image_chunks.push_back(chunk); - chunk_space += GetChunkSize(chunk); - - // fdAT chunks are converted into IDAT chunks when demuxed. The only - // difference between these chunk types is that fdAT has a 4 byte - // sequence number prepended to its data, so subtract that space from - // the buffer. - if (chunk->get_type() == kFrameDataChunkType) { - chunk_space -= 4; - } - } - - chunk = GetNextChunk(buffer_p, buffer_size, chunk); - } while (chunk != nullptr && chunk->get_type() != kFrameControlChunkType && - chunk->get_type() != kImageTrailerChunkType); - - const uint8_t end_chunk[] = {0, 0, 0, 0, 'I', 'E', - 'N', 'D', 0xAE, 0x42, 0x60, 0x82}; - - // Form a buffer for the new encoded PNG and copy the chunks in. - sk_sp<SkData> new_png_buffer = SkData::MakeUninitialized( - header.size() + chunk_space + sizeof(end_chunk)); - - { - uint8_t* write_cursor = - static_cast<uint8_t*>(new_png_buffer->writable_data()); - - // Copy the signature/header chunks - memcpy(write_cursor, header.data(), header.size()); - // If this is a frame, override the width/height in the IHDR chunk. - if (control_data) { - ChunkHeader* ihdr_header = - reinterpret_cast<ChunkHeader*>(write_cursor + sizeof(kPngSignature)); - ImageHeaderChunkData* ihdr_data = const_cast<ImageHeaderChunkData*>( - CastChunkData<ImageHeaderChunkData>(ihdr_header)); - ihdr_data->set_width(control_data->get_width()); - ihdr_data->set_height(control_data->get_height()); - ihdr_header->UpdateChunkCrc32(); - } - write_cursor += header.size(); - - // Copy the image data/ancillary chunks. - for (const ChunkHeader* c : image_chunks) { - if (c->get_type() == kFrameDataChunkType) { - // Write a new IDAT chunk header. - ChunkHeader* write_header = - reinterpret_cast<ChunkHeader*>(write_cursor); - write_header->set_data_length(c->get_data_length() - 4); - write_header->set_type(kImageDataChunkType); - write_cursor += sizeof(ChunkHeader); - - // Copy all of the data except for the 4 byte sequence number at the - // beginning of the fdAT data. - memcpy(write_cursor, - reinterpret_cast<const uint8_t*>(c) + sizeof(ChunkHeader) + 4, - write_header->get_data_length()); - write_cursor += write_header->get_data_length(); - - // Recompute the chunk CRC. - write_header->UpdateChunkCrc32(); - write_cursor += 4; - } else { - size_t chunk_size = GetChunkSize(c); - memcpy(write_cursor, c, chunk_size); - write_cursor += chunk_size; - } - } - - // Copy the trailer chunk. - memcpy(write_cursor, &end_chunk, sizeof(end_chunk)); - } - - SkCodec::Result header_parse_result; - result.codec = SkPngCodec::MakeFromStream( - SkMemoryStream::Make(new_png_buffer), &header_parse_result); - if (header_parse_result != SkCodec::Result::kSuccess) { - FML_DLOG(ERROR) - << "Failed to parse image header during APNG demux. SkCodec::Result: " - << header_parse_result; - return std::make_pair(std::nullopt, nullptr); - } - - if (chunk->get_type() == kImageTrailerChunkType) { - chunk = nullptr; - } - - return std::make_pair(std::optional<APNGImage>{std::move(result)}, chunk); -} - -bool APNGImageGenerator::DemuxNextImageInternal() { - if (next_chunk_p_ == nullptr) { - return false; - } - - std::optional<APNGImage> image; - const void* data_p = const_cast<void*>(data_.get()->data()); - std::tie(image, next_chunk_p_) = - DemuxNextImage(data_p, data_->size(), header_, next_chunk_p_); - if (!image.has_value()) { - return false; - } - - if (images_.back().frame_info->disposal_method == - SkCodecAnimation::DisposalMethod::kRestorePrevious) { - FML_DLOG(INFO) - << "DisposalMethod::kRestorePrevious is not supported by the " - "MultiFrameCodec. Falling back to DisposalMethod::kRestoreBGColor " - " behavior instead."; - } - - if (images_.size() > first_frame_index_ && - images_.back().frame_info->disposal_method == - SkCodecAnimation::DisposalMethod::kKeep) { - // Mark the required frame as the previous frame in all cases. - image->frame_info->required_frame = images_.size() - 1; - } - - // Calling SkCodec::getInfo at least once prior to decoding is mandatory. - SkImageInfo info = image.value().codec->getInfo(); - FML_DCHECK(info.colorInfo() == image_info_.colorInfo()); - - images_.push_back(std::move(image.value())); - - auto default_info = images_[0].codec->getInfo(); - if (info.colorType() != default_info.colorType()) { - return false; - } - return true; -} - -bool APNGImageGenerator::DemuxToImageIndex(unsigned int image_index) { - // If the requested image doesn't exist yet, demux more frames from the APNG - // stream. - if (image_index >= images_.size()) { - while (DemuxNextImageInternal() && image_index >= images_.size()) { - } - - if (image_index >= images_.size()) { - // The chunk stream was exhausted before the image was found. - return false; - } - } - - return true; -} - -void APNGImageGenerator::ChunkHeader::UpdateChunkCrc32() { - uint32_t* crc_p = - reinterpret_cast<uint32_t*>(reinterpret_cast<uint8_t*>(this) + - sizeof(ChunkHeader) + get_data_length()); - *crc_p = fml::BigEndianToArch(ComputeChunkCrc32()); -} - -uint32_t APNGImageGenerator::ChunkHeader::ComputeChunkCrc32() { - // Exclude the length field at the beginning of the chunk header. - size_t length = sizeof(ChunkHeader) - 4 + get_data_length(); - uint8_t* chunk_data_p = reinterpret_cast<uint8_t*>(this) + 4; - uint32_t crc = 0; - - // zlib's crc32 can only take 16 bits at a time for the length, but PNG - // supports a 32 bit chunk length, so looping is necessary here. - // Note that crc32 is always called at least once, even if the chunk has an - // empty data section. - do { - uint16_t length16 = length; - if (length16 == 0 && length > 0) { - length16 = std::numeric_limits<uint16_t>::max(); - } - - crc = crc32(crc, chunk_data_p, length16); - length -= length16; - chunk_data_p += length16; - } while (length > 0); - - return crc; -} - -bool APNGImageGenerator::RenderDefaultImage(const SkImageInfo& info, - void* pixels, - size_t row_bytes) { - SkCodec::Result result = images_[0].codec->getPixels(info, pixels, row_bytes); - if (result != SkCodec::kSuccess) { - FML_DLOG(ERROR) << "Failed to decode the APNG's default/fallback image. " - "SkCodec::Result: " - << result; - return false; - } - return true; -} - -} // namespace flutter
diff --git a/lib/ui/painting/image_generator_apng.h b/lib/ui/painting/image_generator_apng.h deleted file mode 100644 index a18ef58..0000000 --- a/lib/ui/painting/image_generator_apng.h +++ /dev/null
@@ -1,216 +0,0 @@ -// Copyright 2013 The Flutter Authors. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be -// found in the LICENSE file. - -#include "image_generator.h" - -#include "flutter/fml/endianness.h" -#include "flutter/fml/logging.h" - -#define PNG_FIELD(T, name) \ - private: \ - T name; \ - \ - public: \ - T get_##name() const { \ - return fml::BigEndianToArch<T>(name); \ - } \ - void set_##name(T n) { \ - name = fml::BigEndianToArch<T>(n); \ - } - -namespace flutter { - -class APNGImageGenerator : public ImageGenerator { - public: - ~APNGImageGenerator(); - - // |ImageGenerator| - const SkImageInfo& GetInfo() override; - - // |ImageGenerator| - unsigned int GetFrameCount() const override; - - // |ImageGenerator| - unsigned int GetPlayCount() const override; - - // |ImageGenerator| - const ImageGenerator::FrameInfo GetFrameInfo( - unsigned int frame_index) override; - - // |ImageGenerator| - SkISize GetScaledDimensions(float desired_scale) override; - - // |ImageGenerator| - bool GetPixels(const SkImageInfo& info, - void* pixels, - size_t row_bytes, - unsigned int frame_index, - std::optional<unsigned int> prior_frame) override; - - static std::unique_ptr<ImageGenerator> MakeFromData(sk_sp<SkData> data); - - private: - static constexpr uint8_t kPngSignature[8] = {137, 80, 78, 71, 13, 10, 26, 10}; - static constexpr size_t kChunkCrcSize = 4; - - enum ChunkType { - kImageHeaderChunkType = 'IHDR', - kAnimationControlChunkType = 'acTL', - kImageDataChunkType = 'IDAT', - kFrameControlChunkType = 'fcTL', - kFrameDataChunkType = 'fdAT', - kImageTrailerChunkType = 'IEND', - }; - - class __attribute__((packed, aligned(1))) ChunkHeader { - PNG_FIELD(uint32_t, data_length) - PNG_FIELD(ChunkType, type) - - public: - void UpdateChunkCrc32(); - - private: - uint32_t ComputeChunkCrc32(); - }; - - class __attribute__((packed, aligned(1))) ImageHeaderChunkData { - PNG_FIELD(uint32_t, width) - PNG_FIELD(uint32_t, height) - PNG_FIELD(uint8_t, bit_depth) - PNG_FIELD(uint8_t, color_type) - PNG_FIELD(uint8_t, compression_method) - PNG_FIELD(uint8_t, filter_method) - PNG_FIELD(uint8_t, interlace_method) - }; - - class __attribute__((packed, aligned(1))) AnimationControlChunkData { - PNG_FIELD(uint32_t, num_frames) - PNG_FIELD(uint32_t, num_plays) - }; - - class __attribute__((packed, aligned(1))) FrameControlChunkData { - PNG_FIELD(uint32_t, sequence_number) - PNG_FIELD(uint32_t, width) - PNG_FIELD(uint32_t, height) - PNG_FIELD(uint32_t, x_offset) - PNG_FIELD(uint32_t, y_offset) - PNG_FIELD(uint16_t, delay_num) - PNG_FIELD(uint16_t, delay_den) - PNG_FIELD(uint8_t, dispose_op) - PNG_FIELD(uint8_t, blend_op) - }; - - /// @brief The first PNG frame is always the "default" PNG frame. Absence of - /// `frame_info` is only possible on the "default" PNG frame. - /// Each frame goes through two decoding stages: - /// 1. Demuxing stage: An individual PNG codec is created for a frame - /// while walking through the APNG chunk stream -- this is placed - /// in the `codec` field. - /// 2. Decoding stage: When a frame is requested for the first time, - /// the decoded image is requested from the `SkCodec` and then - /// (depending on the `frame_info`) composited with a previous - /// frame. The final "canvas" frame is placed in the - /// `composited_image` field. At this point, the `codec` is freed - /// and the `composited_image` is handed to the caller for drawing. - struct APNGImage { - std::unique_ptr<SkCodec> codec; - - // The rendered frame pixels. - std::vector<uint8_t> pixels; - - // Absence of frame info is possible on the "default" image. - std::optional<ImageGenerator::FrameInfo> frame_info; - - // X offset of this image when composited. Only applicable to frames. - unsigned int x_offset; - - // X offset of this image when composited. Only applicable to frames. - unsigned int y_offset; - }; - - APNGImageGenerator(sk_sp<SkData>& data, - SkImageInfo& image_info, - APNGImage&& default_image, - unsigned int frame_count, - unsigned int play_count, - const void* next_chunk_p, - const std::vector<uint8_t>& header); - - static bool IsValidChunkHeader(const void* buffer, - size_t size, - const ChunkHeader* chunk); - - static const ChunkHeader* GetNextChunk(const void* buffer, - size_t size, - const ChunkHeader* current_chunk); - - /// @brief This is a utility template for casting a png buffer pointer to a - /// chunk header. Its primary purpose is to statically insert runtime - /// debug checks that detect invalid decoding behavior. - template <typename T> - static constexpr const T* CastChunkData(const ChunkHeader* chunk) { - if constexpr (std::is_same_v<T, ImageHeaderChunkData>) { - FML_DCHECK(chunk->get_type() == kImageHeaderChunkType); - } else if constexpr (std::is_same_v<T, AnimationControlChunkData>) { - FML_DCHECK(chunk->get_type() == kAnimationControlChunkType); - } else if constexpr (std::is_same_v<T, FrameControlChunkData>) { - FML_DCHECK(chunk->get_type() == kFrameControlChunkType); - } else { - static_assert(!sizeof(T), "Invalid chunk struct"); - } - - return reinterpret_cast<const T*>(reinterpret_cast<const uint8_t*>(chunk) + - sizeof(ChunkHeader)); - } - - static constexpr size_t GetChunkSize(const ChunkHeader* chunk) { - return sizeof(ChunkHeader) + chunk->get_data_length() + kChunkCrcSize; - } - - static constexpr bool IsChunkCopySafe(const ChunkHeader* chunk) { - // The safe-to-copy bit is the 5th bit of the chunk name's 4th byte. This is - // the same as checking that the 4th byte is lowercase. - return (chunk->get_type() & 0x20) != 0; - } - - /// @brief Extract a header that's safe to use for both the "default" image - /// and individual PNG frames. Strip the animation control chunk. - static std::pair<std::optional<std::vector<uint8_t>>, const void*> - ExtractHeader(const void* buffer_p, size_t buffer_size); - - /// @brief Takes a chunk pointer to a chunk and demuxes/interprets the next - /// image in the APNG sequence. It also provides the next `chunk_p` - /// to use. - /// @see `APNGImage` - static std::pair<std::optional<APNGImage>, const void*> DemuxNextImage( - const void* buffer_p, - size_t buffer_size, - const std::vector<uint8_t>& header, - const void* chunk_p); - - bool DemuxNextImageInternal(); - - bool DemuxToImageIndex(unsigned int image_index); - - bool RenderDefaultImage(const SkImageInfo& info, - void* pixels, - size_t row_bytes); - - FML_DISALLOW_COPY_ASSIGN_AND_MOVE(APNGImageGenerator); - sk_sp<SkData> data_; - SkImageInfo image_info_; - unsigned int frame_count_; - unsigned int play_count_; - - // The first image is always the default image, which may or may not be a - // frame. All subsequent images are guaranteed to have frame data. - std::vector<APNGImage> images_; - - unsigned int first_frame_index_; - - const void* next_chunk_p_; - std::vector<uint8_t> header_; -}; - -} // namespace flutter
diff --git a/lib/ui/painting/image_generator_registry.cc b/lib/ui/painting/image_generator_registry.cc index ca5d83a..4460182 100644 --- a/lib/ui/painting/image_generator_registry.cc +++ b/lib/ui/painting/image_generator_registry.cc
@@ -14,19 +14,11 @@ #include "third_party/skia/include/ports/SkImageGeneratorWIC.h" #endif -#include "image_generator_apng.h" - namespace flutter { ImageGeneratorRegistry::ImageGeneratorRegistry() : weak_factory_(this) { AddFactory( [](sk_sp<SkData> buffer) { - return APNGImageGenerator::MakeFromData(std::move(buffer)); - }, - 0); - - AddFactory( - [](sk_sp<SkData> buffer) { return BuiltinSkiaCodecImageGenerator::MakeFromData(std::move(buffer)); }, 0);
diff --git a/lib/ui/painting/image_generator_registry_unittests.cc b/lib/ui/painting/image_generator_registry_unittests.cc index 54eb453..3051e42 100644 --- a/lib/ui/painting/image_generator_registry_unittests.cc +++ b/lib/ui/painting/image_generator_registry_unittests.cc
@@ -62,7 +62,7 @@ unsigned int GetPlayCount() const { return 1; } - const ImageGenerator::FrameInfo GetFrameInfo(unsigned int frame_index) { + const ImageGenerator::FrameInfo GetFrameInfo(unsigned int frame_index) const { return {std::nullopt, 0, SkCodecAnimation::DisposalMethod::kKeep}; }
diff --git a/lib/ui/painting/multi_frame_codec.cc b/lib/ui/painting/multi_frame_codec.cc index a380656..76af13b 100644 --- a/lib/ui/painting/multi_frame_codec.cc +++ b/lib/ui/painting/multi_frame_codec.cc
@@ -107,30 +107,24 @@ std::optional<unsigned int> prior_frame_index = std::nullopt; if (requiredFrameIndex != SkCodec::kNoFrame) { - // We currently assume that frames can only ever depend on the immediately - // previous frame, if any. This means that - // `DisposalMethod::kRestorePrevious` is not supported. if (lastRequiredFrame_ == nullptr) { - FML_DLOG(INFO) - << "Frame " << nextFrameIndex_ << " depends on frame " - << requiredFrameIndex - << " and no required frames are cached. Using blank slate instead."; + FML_LOG(ERROR) << "Frame " << nextFrameIndex_ << " depends on frame " + << requiredFrameIndex + << " and no required frames are cached."; + return nullptr; } else if (lastRequiredFrameIndex_ != requiredFrameIndex) { FML_DLOG(INFO) << "Required frame " << requiredFrameIndex - << " is not cached. Using blank slate instead."; - } else { - // Copy the previous frame's output buffer into the current frame as the - // starting point. - if (lastRequiredFrame_->getPixels() && - CopyToBitmap(&bitmap, lastRequiredFrame_->colorType(), - *lastRequiredFrame_)) { - prior_frame_index = requiredFrameIndex; - } + << " is not cached. Using " << lastRequiredFrameIndex_ + << " instead"; + } + + if (lastRequiredFrame_->getPixels() && + CopyToBitmap(&bitmap, lastRequiredFrame_->colorType(), + *lastRequiredFrame_)) { + prior_frame_index = requiredFrameIndex; } } - // Write the new frame to the output buffer. The bitmap pixels as supplied - // are already set in accordance with the previous frame's disposal policy. if (!generator_->GetPixels(info, bitmap.getPixels(), bitmap.rowBytes(), nextFrameIndex_, requiredFrameIndex)) { FML_LOG(ERROR) << "Could not getPixels for frame " << nextFrameIndex_;
diff --git a/shell/common/shell_unittests.cc b/shell/common/shell_unittests.cc index 0bd2d9e..6f3418f 100644 --- a/shell/common/shell_unittests.cc +++ b/shell/common/shell_unittests.cc
@@ -2249,7 +2249,7 @@ unsigned int GetPlayCount() const { return 1; } - const ImageGenerator::FrameInfo GetFrameInfo(unsigned int frame_index) { + const ImageGenerator::FrameInfo GetFrameInfo(unsigned int frame_index) const { return {std::nullopt, 0, SkCodecAnimation::DisposalMethod::kKeep}; }
diff --git a/shell/platform/android/android_image_generator.cc b/shell/platform/android/android_image_generator.cc index 9ba4c05..714eef9 100644 --- a/shell/platform/android/android_image_generator.cc +++ b/shell/platform/android/android_image_generator.cc
@@ -38,7 +38,7 @@ } const ImageGenerator::FrameInfo AndroidImageGenerator::GetFrameInfo( - unsigned int frame_index) { + unsigned int frame_index) const { return {.required_frame = std::nullopt, .duration = 0, .disposal_method = SkCodecAnimation::DisposalMethod::kKeep};
diff --git a/shell/platform/android/android_image_generator.h b/shell/platform/android/android_image_generator.h index 53cbadd..6d13c94 100644 --- a/shell/platform/android/android_image_generator.h +++ b/shell/platform/android/android_image_generator.h
@@ -32,7 +32,7 @@ // |ImageGenerator| const ImageGenerator::FrameInfo GetFrameInfo( - unsigned int frame_index) override; + unsigned int frame_index) const override; // |ImageGenerator| SkISize GetScaledDimensions(float desired_scale) override;