diff options
Diffstat (limited to 'media/libjxl/src/lib/extras/dec/apng.cc')
| -rw-r--r-- | media/libjxl/src/lib/extras/dec/apng.cc | 797 |
1 files changed, 797 insertions, 0 deletions
diff --git a/media/libjxl/src/lib/extras/dec/apng.cc b/media/libjxl/src/lib/extras/dec/apng.cc new file mode 100644 index 0000000000..566746665d --- /dev/null +++ b/media/libjxl/src/lib/extras/dec/apng.cc @@ -0,0 +1,797 @@ +// Copyright (c) the JPEG XL Project 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 "lib/extras/dec/apng.h" + +// Parts of this code are taken from apngdis, which has the following license: +/* APNG Disassembler 2.8 + * + * Deconstructs APNG files into individual frames. + * + * http://apngdis.sourceforge.net + * + * Copyright (c) 2010-2015 Max Stepin + * maxst at users.sourceforge.net + * + * zlib license + * ------------ + * + * This software is provided 'as-is', without any express or implied + * warranty. In no event will the authors be held liable for any damages + * arising from the use of this software. + * + * Permission is granted to anyone to use this software for any purpose, + * including commercial applications, and to alter it and redistribute it + * freely, subject to the following restrictions: + * + * 1. The origin of this software must not be misrepresented; you must not + * claim that you wrote the original software. If you use this software + * in a product, an acknowledgment in the product documentation would be + * appreciated but is not required. + * 2. Altered source versions must be plainly marked as such, and must not be + * misrepresented as being the original software. + * 3. This notice may not be removed or altered from any source distribution. + * + */ + +#include <stdio.h> +#include <string.h> + +#include <string> +#include <utility> +#include <vector> + +#include "jxl/codestream_header.h" +#include "jxl/encode.h" +#include "lib/jxl/base/compiler_specific.h" +#include "lib/jxl/base/printf_macros.h" +#include "lib/jxl/base/scope_guard.h" +#include "lib/jxl/common.h" +#include "lib/jxl/sanitizers.h" +#include "png.h" /* original (unpatched) libpng is ok */ + +namespace jxl { +namespace extras { + +namespace { + +/* hIST chunk tail is not proccesed properly; skip this chunk completely; + see https://github.com/glennrp/libpng/pull/413 */ +const png_byte kIgnoredPngChunks[] = { + 104, 73, 83, 84, '\0' /* hIST */ +}; + +// Returns floating-point value from the PNG encoding (times 10^5). +static double F64FromU32(const uint32_t x) { + return static_cast<int32_t>(x) * 1E-5; +} + +Status DecodeSRGB(const unsigned char* payload, const size_t payload_size, + JxlColorEncoding* color_encoding) { + if (payload_size != 1) return JXL_FAILURE("Wrong sRGB size"); + // (PNG uses the same values as ICC.) + if (payload[0] >= 4) return JXL_FAILURE("Invalid Rendering Intent"); + color_encoding->rendering_intent = + static_cast<JxlRenderingIntent>(payload[0]); + return true; +} + +Status DecodeGAMA(const unsigned char* payload, const size_t payload_size, + JxlColorEncoding* color_encoding) { + if (payload_size != 4) return JXL_FAILURE("Wrong gAMA size"); + color_encoding->transfer_function = JXL_TRANSFER_FUNCTION_GAMMA; + color_encoding->gamma = F64FromU32(LoadBE32(payload)); + return true; +} + +Status DecodeCHRM(const unsigned char* payload, const size_t payload_size, + JxlColorEncoding* color_encoding) { + if (payload_size != 32) return JXL_FAILURE("Wrong cHRM size"); + + color_encoding->white_point = JXL_WHITE_POINT_CUSTOM; + color_encoding->white_point_xy[0] = F64FromU32(LoadBE32(payload + 0)); + color_encoding->white_point_xy[1] = F64FromU32(LoadBE32(payload + 4)); + + color_encoding->primaries = JXL_PRIMARIES_CUSTOM; + color_encoding->primaries_red_xy[0] = F64FromU32(LoadBE32(payload + 8)); + color_encoding->primaries_red_xy[1] = F64FromU32(LoadBE32(payload + 12)); + color_encoding->primaries_green_xy[0] = F64FromU32(LoadBE32(payload + 16)); + color_encoding->primaries_green_xy[1] = F64FromU32(LoadBE32(payload + 20)); + color_encoding->primaries_blue_xy[0] = F64FromU32(LoadBE32(payload + 24)); + color_encoding->primaries_blue_xy[1] = F64FromU32(LoadBE32(payload + 28)); + return true; +} + +// Retrieves XMP and EXIF/IPTC from itext and text. +class BlobsReaderPNG { + public: + static Status Decode(const png_text_struct& info, PackedMetadata* metadata) { + // We trust these are properly null-terminated by libpng. + const char* key = info.key; + const char* value = info.text; + if (strstr(key, "XML:com.adobe.xmp")) { + metadata->xmp.resize(strlen(value)); // safe, see above + memcpy(metadata->xmp.data(), value, metadata->xmp.size()); + } + + std::string type; + std::vector<uint8_t> bytes; + + // Handle text chunks annotated with key "Raw profile type ####", with + // #### a type, which may contain metadata. + const char* kKey = "Raw profile type "; + if (strncmp(key, kKey, strlen(kKey)) != 0) return false; + + if (!MaybeDecodeBase16(key, value, &type, &bytes)) { + JXL_WARNING("Couldn't parse 'Raw format type' text chunk"); + return false; + } + if (type == "exif") { + if (!metadata->exif.empty()) { + JXL_WARNING("overwriting EXIF (%" PRIuS " bytes) with base16 (%" PRIuS + " bytes)", + metadata->exif.size(), bytes.size()); + } + metadata->exif = std::move(bytes); + } else if (type == "iptc") { + // TODO (jon): Deal with IPTC in some way + } else if (type == "8bim") { + // TODO (jon): Deal with 8bim in some way + } else if (type == "xmp") { + if (!metadata->xmp.empty()) { + JXL_WARNING("overwriting XMP (%" PRIuS " bytes) with base16 (%" PRIuS + " bytes)", + metadata->xmp.size(), bytes.size()); + } + metadata->xmp = std::move(bytes); + } else { + JXL_WARNING("Unknown type in 'Raw format type' text chunk: %s: %" PRIuS + " bytes", + type.c_str(), bytes.size()); + } + return true; + } + + private: + // Returns false if invalid. + static JXL_INLINE Status DecodeNibble(const char c, + uint32_t* JXL_RESTRICT nibble) { + if ('a' <= c && c <= 'f') { + *nibble = 10 + c - 'a'; + } else if ('0' <= c && c <= '9') { + *nibble = c - '0'; + } else { + *nibble = 0; + return JXL_FAILURE("Invalid metadata nibble"); + } + JXL_ASSERT(*nibble < 16); + return true; + } + + // Returns false if invalid. + static JXL_INLINE Status DecodeDecimal(const char** pos, const char* end, + uint32_t* JXL_RESTRICT value) { + size_t len = 0; + *value = 0; + while (*pos < end) { + char next = **pos; + if (next >= '0' && next <= '9') { + *value = (*value * 10) + static_cast<uint32_t>(next - '0'); + len++; + if (len > 8) { + break; + } + } else { + // Do not consume terminator (non-decimal digit). + break; + } + (*pos)++; + } + if (len == 0 || len > 8) { + return JXL_FAILURE("Failed to parse decimal"); + } + return true; + } + + // Parses a PNG text chunk with key of the form "Raw profile type ####", with + // #### a type. + // Returns whether it could successfully parse the content. + // We trust key and encoded are null-terminated because they come from + // libpng. + static Status MaybeDecodeBase16(const char* key, const char* encoded, + std::string* type, + std::vector<uint8_t>* bytes) { + const char* encoded_end = encoded + strlen(encoded); + + const char* kKey = "Raw profile type "; + if (strncmp(key, kKey, strlen(kKey)) != 0) return false; + *type = key + strlen(kKey); + const size_t kMaxTypeLen = 20; + if (type->length() > kMaxTypeLen) return false; // Type too long + + // Header: freeform string and number of bytes + // Expected format is: + // \n + // profile name/description\n + // 40\n (the number of bytes after hex-decoding) + // 01234566789abcdef....\n (72 bytes per line max). + // 012345667\n (last line) + const char* pos = encoded; + + if (*(pos++) != '\n') return false; + while (pos < encoded_end && *pos != '\n') { + pos++; + } + if (pos == encoded_end) return false; + // We parsed so far a \n, some number of non \n characters and are now + // pointing at a \n. + if (*(pos++) != '\n') return false; + uint32_t bytes_to_decode = 0; + JXL_RETURN_IF_ERROR(DecodeDecimal(&pos, encoded_end, &bytes_to_decode)); + + // We need 2*bytes for the hex values plus 1 byte every 36 values, + // plus terminal \n for length. + const unsigned long needed_bytes = + bytes_to_decode * 2 + 1 + DivCeil(bytes_to_decode, 36); + if (needed_bytes != static_cast<size_t>(encoded_end - pos)) { + return JXL_FAILURE("Not enough bytes to parse %d bytes in hex", + bytes_to_decode); + } + JXL_ASSERT(bytes->empty()); + bytes->reserve(bytes_to_decode); + + // Encoding: base16 with newline after 72 chars. + // pos points to the \n before the first line of hex values. + for (size_t i = 0; i < bytes_to_decode; ++i) { + if (i % 36 == 0) { + if (pos + 1 >= encoded_end) return false; // Truncated base16 1 + if (*pos != '\n') return false; // Expected newline + ++pos; + } + + if (pos + 2 >= encoded_end) return false; // Truncated base16 2; + uint32_t nibble0, nibble1; + JXL_RETURN_IF_ERROR(DecodeNibble(pos[0], &nibble0)); + JXL_RETURN_IF_ERROR(DecodeNibble(pos[1], &nibble1)); + bytes->push_back(static_cast<uint8_t>((nibble0 << 4) + nibble1)); + pos += 2; + } + if (pos + 1 != encoded_end) return false; // Too many encoded bytes + if (pos[0] != '\n') return false; // Incorrect metadata terminator + return true; + } +}; + +constexpr bool isAbc(char c) { + return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z'); +} + +constexpr uint32_t kId_IHDR = 0x52444849; +constexpr uint32_t kId_acTL = 0x4C546361; +constexpr uint32_t kId_fcTL = 0x4C546366; +constexpr uint32_t kId_IDAT = 0x54414449; +constexpr uint32_t kId_fdAT = 0x54416466; +constexpr uint32_t kId_IEND = 0x444E4549; +constexpr uint32_t kId_iCCP = 0x50434369; +constexpr uint32_t kId_sRGB = 0x42475273; +constexpr uint32_t kId_gAMA = 0x414D4167; +constexpr uint32_t kId_cHRM = 0x4D524863; +constexpr uint32_t kId_eXIf = 0x66495865; + +struct APNGFrame { + std::vector<uint8_t> pixels; + std::vector<uint8_t*> rows; + unsigned int w, h, delay_num, delay_den; +}; + +struct Reader { + const uint8_t* next; + const uint8_t* last; + bool Read(void* data, size_t len) { + size_t cap = last - next; + size_t to_copy = std::min(cap, len); + memcpy(data, next, to_copy); + next += to_copy; + return (len == to_copy); + } + bool Eof() { return next == last; } +}; + +const unsigned long cMaxPNGSize = 1000000UL; +const size_t kMaxPNGChunkSize = 1lu << 30; // 1 GB + +void info_fn(png_structp png_ptr, png_infop info_ptr) { + png_set_expand(png_ptr); + png_set_palette_to_rgb(png_ptr); + png_set_tRNS_to_alpha(png_ptr); + (void)png_set_interlace_handling(png_ptr); + png_read_update_info(png_ptr, info_ptr); +} + +void row_fn(png_structp png_ptr, png_bytep new_row, png_uint_32 row_num, + int pass) { + APNGFrame* frame = (APNGFrame*)png_get_progressive_ptr(png_ptr); + JXL_CHECK(frame); + JXL_CHECK(row_num < frame->rows.size()); + JXL_CHECK(frame->rows[row_num] < frame->pixels.data() + frame->pixels.size()); + png_progressive_combine_row(png_ptr, frame->rows[row_num], new_row); +} + +inline unsigned int read_chunk(Reader* r, std::vector<uint8_t>* pChunk) { + unsigned char len[4]; + if (r->Read(&len, 4)) { + const auto size = png_get_uint_32(len); + // Check first, to avoid overflow. + if (size > kMaxPNGChunkSize) { + JXL_WARNING("APNG chunk size is too big"); + return 0; + } + pChunk->resize(size + 12); + memcpy(pChunk->data(), len, 4); + if (r->Read(pChunk->data() + 4, pChunk->size() - 4)) { + return LoadLE32(pChunk->data() + 4); + } + } + return 0; +} + +int processing_start(png_structp& png_ptr, png_infop& info_ptr, void* frame_ptr, + bool hasInfo, std::vector<uint8_t>& chunkIHDR, + std::vector<std::vector<uint8_t>>& chunksInfo) { + unsigned char header[8] = {137, 80, 78, 71, 13, 10, 26, 10}; + + png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); + info_ptr = png_create_info_struct(png_ptr); + if (!png_ptr || !info_ptr) return 1; + + if (setjmp(png_jmpbuf(png_ptr))) { + return 1; + } + + png_set_keep_unknown_chunks(png_ptr, 1, kIgnoredPngChunks, + (int)sizeof(kIgnoredPngChunks) / 5); + + png_set_crc_action(png_ptr, PNG_CRC_QUIET_USE, PNG_CRC_QUIET_USE); + png_set_progressive_read_fn(png_ptr, frame_ptr, info_fn, row_fn, NULL); + + png_process_data(png_ptr, info_ptr, header, 8); + png_process_data(png_ptr, info_ptr, chunkIHDR.data(), chunkIHDR.size()); + + if (hasInfo) { + for (unsigned int i = 0; i < chunksInfo.size(); i++) { + png_process_data(png_ptr, info_ptr, chunksInfo[i].data(), + chunksInfo[i].size()); + } + } + return 0; +} + +int processing_data(png_structp png_ptr, png_infop info_ptr, unsigned char* p, + unsigned int size) { + if (!png_ptr || !info_ptr) return 1; + + if (setjmp(png_jmpbuf(png_ptr))) { + return 1; + } + + png_process_data(png_ptr, info_ptr, p, size); + return 0; +} + +int processing_finish(png_structp png_ptr, png_infop info_ptr, + PackedMetadata* metadata) { + unsigned char footer[12] = {0, 0, 0, 0, 73, 69, 78, 68, 174, 66, 96, 130}; + + if (!png_ptr || !info_ptr) return 1; + + if (setjmp(png_jmpbuf(png_ptr))) { + return 1; + } + + png_process_data(png_ptr, info_ptr, footer, 12); + // before destroying: check if we encountered any metadata chunks + png_textp text_ptr; + int num_text; + png_get_text(png_ptr, info_ptr, &text_ptr, &num_text); + for (int i = 0; i < num_text; i++) { + (void)BlobsReaderPNG::Decode(text_ptr[i], metadata); + } + + return 0; +} + +} // namespace + +Status DecodeImageAPNG(const Span<const uint8_t> bytes, + const ColorHints& color_hints, + const SizeConstraints& constraints, + PackedPixelFile* ppf) { + Reader r; + unsigned int id, j, w, h, w0, h0, x0, y0; + unsigned int delay_num, delay_den, dop, bop, rowbytes, imagesize; + unsigned char sig[8]; + png_structp png_ptr = nullptr; + png_infop info_ptr = nullptr; + std::vector<uint8_t> chunk; + std::vector<uint8_t> chunkIHDR; + std::vector<std::vector<uint8_t>> chunksInfo; + bool isAnimated = false; + bool hasInfo = false; + APNGFrame frameRaw = {}; + uint32_t num_channels; + JxlPixelFormat format; + unsigned int bytes_per_pixel = 0; + + struct FrameInfo { + PackedImage data; + uint32_t duration; + size_t x0, xsize; + size_t y0, ysize; + uint32_t dispose_op; + uint32_t blend_op; + }; + + std::vector<FrameInfo> frames; + + // Make sure png memory is released in any case. + auto scope_guard = MakeScopeGuard([&]() { + png_destroy_read_struct(&png_ptr, &info_ptr, 0); + // Just in case. Not all versions on libpng wipe-out the pointers. + png_ptr = nullptr; + info_ptr = nullptr; + }); + + r = {bytes.data(), bytes.data() + bytes.size()}; + // Not a PNG => not an error + unsigned char png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10}; + if (!r.Read(sig, 8) || memcmp(sig, png_signature, 8) != 0) { + return false; + } + id = read_chunk(&r, &chunkIHDR); + + ppf->info.exponent_bits_per_sample = 0; + ppf->info.alpha_exponent_bits = 0; + ppf->info.orientation = JXL_ORIENT_IDENTITY; + + ppf->frames.clear(); + + bool have_color = false, have_srgb = false; + bool errorstate = true; + if (id == kId_IHDR && chunkIHDR.size() == 25) { + x0 = 0; + y0 = 0; + delay_num = 1; + delay_den = 10; + dop = 0; + bop = 0; + + w0 = w = png_get_uint_32(chunkIHDR.data() + 8); + h0 = h = png_get_uint_32(chunkIHDR.data() + 12); + if (w > cMaxPNGSize || h > cMaxPNGSize) { + return false; + } + + // default settings in case e.g. only gAMA is given + ppf->color_encoding.color_space = JXL_COLOR_SPACE_RGB; + ppf->color_encoding.white_point = JXL_WHITE_POINT_D65; + ppf->color_encoding.primaries = JXL_PRIMARIES_SRGB; + ppf->color_encoding.transfer_function = JXL_TRANSFER_FUNCTION_SRGB; + + if (!processing_start(png_ptr, info_ptr, (void*)&frameRaw, hasInfo, + chunkIHDR, chunksInfo)) { + while (!r.Eof()) { + id = read_chunk(&r, &chunk); + if (!id) break; + + if (id == kId_acTL && !hasInfo && !isAnimated) { + isAnimated = true; + ppf->info.have_animation = true; + ppf->info.animation.tps_numerator = 1000; + ppf->info.animation.tps_denominator = 1; + } else if (id == kId_IEND || + (id == kId_fcTL && (!hasInfo || isAnimated))) { + if (hasInfo) { + if (!processing_finish(png_ptr, info_ptr, &ppf->metadata)) { + // Allocates the frame buffer. + uint32_t duration = delay_num * 1000 / delay_den; + frames.push_back(FrameInfo{PackedImage(w0, h0, format), duration, + x0, w0, y0, h0, dop, bop}); + auto& frame = frames.back().data; + for (size_t y = 0; y < h0; ++y) { + memcpy(static_cast<uint8_t*>(frame.pixels()) + frame.stride * y, + frameRaw.rows[y], bytes_per_pixel * w0); + } + } else { + break; + } + } + + if (id == kId_IEND) { + errorstate = false; + break; + } + if (chunk.size() < 34) { + return JXL_FAILURE("Received a chunk that is too small (%" PRIuS + "B)", + chunk.size()); + } + // At this point the old frame is done. Let's start a new one. + w0 = png_get_uint_32(chunk.data() + 12); + h0 = png_get_uint_32(chunk.data() + 16); + x0 = png_get_uint_32(chunk.data() + 20); + y0 = png_get_uint_32(chunk.data() + 24); + delay_num = png_get_uint_16(chunk.data() + 28); + delay_den = png_get_uint_16(chunk.data() + 30); + dop = chunk[32]; + bop = chunk[33]; + + if (!delay_den) delay_den = 100; + + if (w0 > cMaxPNGSize || h0 > cMaxPNGSize || x0 > cMaxPNGSize || + y0 > cMaxPNGSize || x0 + w0 > w || y0 + h0 > h || dop > 2 || + bop > 1) { + break; + } + + if (hasInfo) { + memcpy(chunkIHDR.data() + 8, chunk.data() + 12, 8); + if (processing_start(png_ptr, info_ptr, (void*)&frameRaw, hasInfo, + chunkIHDR, chunksInfo)) { + break; + } + } + } else if (id == kId_IDAT) { + // First IDAT chunk means we now have all header info + hasInfo = true; + JXL_CHECK(w == png_get_image_width(png_ptr, info_ptr)); + JXL_CHECK(h == png_get_image_height(png_ptr, info_ptr)); + int colortype = png_get_color_type(png_ptr, info_ptr); + ppf->info.bits_per_sample = png_get_bit_depth(png_ptr, info_ptr); + png_color_8p sigbits = NULL; + png_get_sBIT(png_ptr, info_ptr, &sigbits); + if (colortype & 1) { + // palette will actually be 8-bit regardless of the index bitdepth + ppf->info.bits_per_sample = 8; + } + if (colortype & 2) { + ppf->info.num_color_channels = 3; + ppf->color_encoding.color_space = JXL_COLOR_SPACE_RGB; + if (sigbits && sigbits->red == sigbits->green && + sigbits->green == sigbits->blue) + ppf->info.bits_per_sample = sigbits->red; + } else { + ppf->info.num_color_channels = 1; + ppf->color_encoding.color_space = JXL_COLOR_SPACE_GRAY; + if (sigbits) ppf->info.bits_per_sample = sigbits->gray; + } + if (colortype & 4 || + png_get_valid(png_ptr, info_ptr, PNG_INFO_tRNS)) { + ppf->info.alpha_bits = ppf->info.bits_per_sample; + if (sigbits) { + if (sigbits->alpha && + sigbits->alpha != ppf->info.bits_per_sample) { + return JXL_FAILURE("Unsupported alpha bit-depth"); + } + ppf->info.alpha_bits = sigbits->alpha; + } + } else { + ppf->info.alpha_bits = 0; + } + ppf->color_encoding.color_space = + (ppf->info.num_color_channels == 1 ? JXL_COLOR_SPACE_GRAY + : JXL_COLOR_SPACE_RGB); + ppf->info.xsize = w; + ppf->info.ysize = h; + JXL_RETURN_IF_ERROR(VerifyDimensions(&constraints, w, h)); + num_channels = + ppf->info.num_color_channels + (ppf->info.alpha_bits ? 1 : 0); + format = { + /*num_channels=*/num_channels, + /*data_type=*/ppf->info.bits_per_sample > 8 ? JXL_TYPE_UINT16 + : JXL_TYPE_UINT8, + /*endianness=*/JXL_BIG_ENDIAN, + /*align=*/0, + }; + bytes_per_pixel = + num_channels * (format.data_type == JXL_TYPE_UINT16 ? 2 : 1); + rowbytes = w * bytes_per_pixel; + imagesize = h * rowbytes; + frameRaw.pixels.resize(imagesize); + frameRaw.rows.resize(h); + for (j = 0; j < h; j++) + frameRaw.rows[j] = frameRaw.pixels.data() + j * rowbytes; + + if (processing_data(png_ptr, info_ptr, chunk.data(), chunk.size())) { + break; + } + } else if (id == kId_fdAT && isAnimated) { + png_save_uint_32(chunk.data() + 4, chunk.size() - 16); + memcpy(chunk.data() + 8, "IDAT", 4); + if (processing_data(png_ptr, info_ptr, chunk.data() + 4, + chunk.size() - 4)) { + break; + } + } else if (id == kId_iCCP) { + if (processing_data(png_ptr, info_ptr, chunk.data(), chunk.size())) { + JXL_WARNING("Corrupt iCCP chunk"); + break; + } + + // TODO(jon): catch special case of PQ and synthesize color encoding + // in that case + int compression_type; + png_bytep profile; + png_charp name; + png_uint_32 proflen = 0; + auto ok = png_get_iCCP(png_ptr, info_ptr, &name, &compression_type, + &profile, &proflen); + if (ok && proflen) { + ppf->icc.assign(profile, profile + proflen); + have_color = true; + } else { + // TODO(eustas): JXL_WARNING? + } + } else if (id == kId_sRGB) { + JXL_RETURN_IF_ERROR(DecodeSRGB(chunk.data() + 8, chunk.size() - 12, + &ppf->color_encoding)); + have_srgb = true; + have_color = true; + } else if (id == kId_gAMA) { + JXL_RETURN_IF_ERROR(DecodeGAMA(chunk.data() + 8, chunk.size() - 12, + &ppf->color_encoding)); + have_color = true; + } else if (id == kId_cHRM) { + JXL_RETURN_IF_ERROR(DecodeCHRM(chunk.data() + 8, chunk.size() - 12, + &ppf->color_encoding)); + have_color = true; + } else if (id == kId_eXIf) { + ppf->metadata.exif.resize(chunk.size() - 12); + memcpy(ppf->metadata.exif.data(), chunk.data() + 8, + chunk.size() - 12); + } else if (!isAbc(chunk[4]) || !isAbc(chunk[5]) || !isAbc(chunk[6]) || + !isAbc(chunk[7])) { + break; + } else { + if (processing_data(png_ptr, info_ptr, chunk.data(), chunk.size())) { + break; + } + if (!hasInfo) { + chunksInfo.push_back(chunk); + continue; + } + } + } + } + + if (have_srgb) { + ppf->color_encoding.white_point = JXL_WHITE_POINT_D65; + ppf->color_encoding.primaries = JXL_PRIMARIES_SRGB; + ppf->color_encoding.transfer_function = JXL_TRANSFER_FUNCTION_SRGB; + ppf->color_encoding.rendering_intent = JXL_RENDERING_INTENT_PERCEPTUAL; + } + JXL_RETURN_IF_ERROR(ApplyColorHints( + color_hints, have_color, ppf->info.num_color_channels == 1, ppf)); + } + + if (errorstate) return false; + + bool has_nontrivial_background = false; + bool previous_frame_should_be_cleared = false; + enum { + DISPOSE_OP_NONE = 0, + DISPOSE_OP_BACKGROUND = 1, + DISPOSE_OP_PREVIOUS = 2, + }; + enum { + BLEND_OP_SOURCE = 0, + BLEND_OP_OVER = 1, + }; + for (size_t i = 0; i < frames.size(); i++) { + auto& frame = frames[i]; + JXL_ASSERT(frame.data.xsize == frame.xsize); + JXL_ASSERT(frame.data.ysize == frame.ysize); + + // Before encountering a DISPOSE_OP_NONE frame, the canvas is filled with 0, + // so DISPOSE_OP_BACKGROUND and DISPOSE_OP_PREVIOUS are equivalent. + if (frame.dispose_op == DISPOSE_OP_NONE) { + has_nontrivial_background = true; + } + bool should_blend = frame.blend_op == BLEND_OP_OVER; + bool use_for_next_frame = + has_nontrivial_background && frame.dispose_op != DISPOSE_OP_PREVIOUS; + size_t x0 = frame.x0; + size_t y0 = frame.y0; + size_t xsize = frame.data.xsize; + size_t ysize = frame.data.ysize; + if (previous_frame_should_be_cleared) { + size_t xs = frame.data.xsize; + size_t ys = frame.data.ysize; + size_t px0 = frames[i - 1].x0; + size_t py0 = frames[i - 1].y0; + size_t pxs = frames[i - 1].xsize; + size_t pys = frames[i - 1].ysize; + if (px0 >= x0 && py0 >= y0 && px0 + pxs <= x0 + xs && + py0 + pys <= y0 + ys && frame.blend_op == BLEND_OP_SOURCE && + use_for_next_frame) { + // If the previous frame is entirely contained in the current frame and + // we are using BLEND_OP_SOURCE, nothing special needs to be done. + ppf->frames.emplace_back(std::move(frame.data)); + } else if (px0 == x0 && py0 == y0 && px0 + pxs == x0 + xs && + py0 + pys == y0 + ys && use_for_next_frame) { + // If the new frame has the same size as the old one, but we are + // blending, we can instead just not blend. + should_blend = false; + ppf->frames.emplace_back(std::move(frame.data)); + } else if (px0 <= x0 && py0 <= y0 && px0 + pxs >= x0 + xs && + py0 + pys >= y0 + ys && use_for_next_frame) { + // If the new frame is contained within the old frame, we can pad the + // new frame with zeros and not blend. + PackedImage new_data(pxs, pys, frame.data.format); + memset(new_data.pixels(), 0, new_data.pixels_size); + for (size_t y = 0; y < ys; y++) { + size_t bytes_per_pixel = + PackedImage::BitsPerChannel(new_data.format.data_type) * + new_data.format.num_channels / 8; + memcpy(static_cast<uint8_t*>(new_data.pixels()) + + new_data.stride * (y + y0 - py0) + + bytes_per_pixel * (x0 - px0), + static_cast<const uint8_t*>(frame.data.pixels()) + + frame.data.stride * y, + xs * bytes_per_pixel); + } + + x0 = px0; + y0 = py0; + xsize = pxs; + ysize = pys; + should_blend = false; + ppf->frames.emplace_back(std::move(new_data)); + } else { + // If all else fails, insert a dummy blank frame with kReplace. + PackedImage blank(pxs, pys, frame.data.format); + memset(blank.pixels(), 0, blank.pixels_size); + ppf->frames.emplace_back(std::move(blank)); + auto& pframe = ppf->frames.back(); + pframe.frame_info.layer_info.crop_x0 = px0; + pframe.frame_info.layer_info.crop_y0 = py0; + pframe.frame_info.layer_info.xsize = frame.xsize; + pframe.frame_info.layer_info.ysize = frame.ysize; + pframe.frame_info.duration = 0; + pframe.frame_info.layer_info.have_crop = 0; + pframe.frame_info.layer_info.blend_info.blendmode = JXL_BLEND_REPLACE; + pframe.frame_info.layer_info.blend_info.source = 0; + pframe.frame_info.layer_info.save_as_reference = 1; + ppf->frames.emplace_back(std::move(frame.data)); + } + } else { + ppf->frames.emplace_back(std::move(frame.data)); + } + + auto& pframe = ppf->frames.back(); + pframe.frame_info.layer_info.crop_x0 = x0; + pframe.frame_info.layer_info.crop_y0 = y0; + pframe.frame_info.layer_info.xsize = xsize; + pframe.frame_info.layer_info.ysize = ysize; + pframe.frame_info.duration = frame.duration; + pframe.frame_info.layer_info.blend_info.blendmode = + should_blend ? JXL_BLEND_BLEND : JXL_BLEND_REPLACE; + bool is_full_size = x0 == 0 && y0 == 0 && xsize == ppf->info.xsize && + ysize == ppf->info.ysize; + pframe.frame_info.layer_info.have_crop = is_full_size ? 0 : 1; + pframe.frame_info.layer_info.blend_info.source = should_blend ? 1 : 0; + pframe.frame_info.layer_info.blend_info.alpha = 0; + pframe.frame_info.layer_info.save_as_reference = use_for_next_frame ? 1 : 0; + + previous_frame_should_be_cleared = + has_nontrivial_background && frame.dispose_op == DISPOSE_OP_BACKGROUND; + } + if (ppf->frames.empty()) return JXL_FAILURE("No frames decoded"); + ppf->frames.back().frame_info.is_last = true; + + return true; +} + +} // namespace extras +} // namespace jxl |