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-rw-r--r--third_party/jpeg-xl/lib/jxl/fields.cc642
1 files changed, 642 insertions, 0 deletions
diff --git a/third_party/jpeg-xl/lib/jxl/fields.cc b/third_party/jpeg-xl/lib/jxl/fields.cc
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index 0000000000..cd1e72bd94
--- /dev/null
+++ b/third_party/jpeg-xl/lib/jxl/fields.cc
@@ -0,0 +1,642 @@
+// 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/jxl/fields.h"
+
+#include <stddef.h>
+
+#include <algorithm>
+#include <cmath>
+#include <hwy/base.h>
+
+#include "lib/jxl/base/bits.h"
+#include "lib/jxl/base/printf_macros.h"
+
+namespace jxl {
+
+namespace {
+
+using ::jxl::fields_internal::VisitorBase;
+
+struct InitVisitor : public VisitorBase {
+ Status Bits(const size_t /*unused*/, const uint32_t default_value,
+ uint32_t* JXL_RESTRICT value) override {
+ *value = default_value;
+ return true;
+ }
+
+ Status U32(const U32Enc /*unused*/, const uint32_t default_value,
+ uint32_t* JXL_RESTRICT value) override {
+ *value = default_value;
+ return true;
+ }
+
+ Status U64(const uint64_t default_value,
+ uint64_t* JXL_RESTRICT value) override {
+ *value = default_value;
+ return true;
+ }
+
+ Status Bool(bool default_value, bool* JXL_RESTRICT value) override {
+ *value = default_value;
+ return true;
+ }
+
+ Status F16(const float default_value, float* JXL_RESTRICT value) override {
+ *value = default_value;
+ return true;
+ }
+
+ // Always visit conditional fields to ensure they are initialized.
+ Status Conditional(bool /*condition*/) override { return true; }
+
+ Status AllDefault(const Fields& /*fields*/,
+ bool* JXL_RESTRICT all_default) override {
+ // Just initialize this field and don't skip initializing others.
+ JXL_RETURN_IF_ERROR(Bool(true, all_default));
+ return false;
+ }
+
+ Status VisitNested(Fields* /*fields*/) override {
+ // Avoid re-initializing nested bundles (their ctors already called
+ // Bundle::Init for their fields).
+ return true;
+ }
+};
+
+// Similar to InitVisitor, but also initializes nested fields.
+struct SetDefaultVisitor : public VisitorBase {
+ Status Bits(const size_t /*unused*/, const uint32_t default_value,
+ uint32_t* JXL_RESTRICT value) override {
+ *value = default_value;
+ return true;
+ }
+
+ Status U32(const U32Enc /*unused*/, const uint32_t default_value,
+ uint32_t* JXL_RESTRICT value) override {
+ *value = default_value;
+ return true;
+ }
+
+ Status U64(const uint64_t default_value,
+ uint64_t* JXL_RESTRICT value) override {
+ *value = default_value;
+ return true;
+ }
+
+ Status Bool(bool default_value, bool* JXL_RESTRICT value) override {
+ *value = default_value;
+ return true;
+ }
+
+ Status F16(const float default_value, float* JXL_RESTRICT value) override {
+ *value = default_value;
+ return true;
+ }
+
+ // Always visit conditional fields to ensure they are initialized.
+ Status Conditional(bool /*condition*/) override { return true; }
+
+ Status AllDefault(const Fields& /*fields*/,
+ bool* JXL_RESTRICT all_default) override {
+ // Just initialize this field and don't skip initializing others.
+ JXL_RETURN_IF_ERROR(Bool(true, all_default));
+ return false;
+ }
+};
+
+class AllDefaultVisitor : public VisitorBase {
+ public:
+ explicit AllDefaultVisitor() : VisitorBase() {}
+
+ Status Bits(const size_t bits, const uint32_t default_value,
+ uint32_t* JXL_RESTRICT value) override {
+ all_default_ &= *value == default_value;
+ return true;
+ }
+
+ Status U32(const U32Enc /*unused*/, const uint32_t default_value,
+ uint32_t* JXL_RESTRICT value) override {
+ all_default_ &= *value == default_value;
+ return true;
+ }
+
+ Status U64(const uint64_t default_value,
+ uint64_t* JXL_RESTRICT value) override {
+ all_default_ &= *value == default_value;
+ return true;
+ }
+
+ Status F16(const float default_value, float* JXL_RESTRICT value) override {
+ all_default_ &= std::abs(*value - default_value) < 1E-6f;
+ return true;
+ }
+
+ Status AllDefault(const Fields& /*fields*/,
+ bool* JXL_RESTRICT /*all_default*/) override {
+ // Visit all fields so we can compute the actual all_default_ value.
+ return false;
+ }
+
+ bool AllDefault() const { return all_default_; }
+
+ private:
+ bool all_default_ = true;
+};
+
+class ReadVisitor : public VisitorBase {
+ public:
+ explicit ReadVisitor(BitReader* reader) : VisitorBase(), reader_(reader) {}
+
+ Status Bits(const size_t bits, const uint32_t /*default_value*/,
+ uint32_t* JXL_RESTRICT value) override {
+ *value = BitsCoder::Read(bits, reader_);
+ if (!reader_->AllReadsWithinBounds()) {
+ return JXL_STATUS(StatusCode::kNotEnoughBytes,
+ "Not enough bytes for header");
+ }
+ return true;
+ }
+
+ Status U32(const U32Enc dist, const uint32_t /*default_value*/,
+ uint32_t* JXL_RESTRICT value) override {
+ *value = U32Coder::Read(dist, reader_);
+ if (!reader_->AllReadsWithinBounds()) {
+ return JXL_STATUS(StatusCode::kNotEnoughBytes,
+ "Not enough bytes for header");
+ }
+ return true;
+ }
+
+ Status U64(const uint64_t /*default_value*/,
+ uint64_t* JXL_RESTRICT value) override {
+ *value = U64Coder::Read(reader_);
+ if (!reader_->AllReadsWithinBounds()) {
+ return JXL_STATUS(StatusCode::kNotEnoughBytes,
+ "Not enough bytes for header");
+ }
+ return true;
+ }
+
+ Status F16(const float /*default_value*/,
+ float* JXL_RESTRICT value) override {
+ ok_ &= F16Coder::Read(reader_, value);
+ if (!reader_->AllReadsWithinBounds()) {
+ return JXL_STATUS(StatusCode::kNotEnoughBytes,
+ "Not enough bytes for header");
+ }
+ return true;
+ }
+
+ void SetDefault(Fields* fields) override { Bundle::SetDefault(fields); }
+
+ bool IsReading() const override { return true; }
+
+ // This never fails because visitors are expected to keep reading until
+ // EndExtensions, see comment there.
+ Status BeginExtensions(uint64_t* JXL_RESTRICT extensions) override {
+ JXL_QUIET_RETURN_IF_ERROR(VisitorBase::BeginExtensions(extensions));
+ if (*extensions == 0) return true;
+
+ // For each nonzero bit, i.e. extension that is present:
+ for (uint64_t remaining_extensions = *extensions; remaining_extensions != 0;
+ remaining_extensions &= remaining_extensions - 1) {
+ const size_t idx_extension =
+ Num0BitsBelowLS1Bit_Nonzero(remaining_extensions);
+ // Read additional U64 (one per extension) indicating the number of bits
+ // (allows skipping individual extensions).
+ JXL_RETURN_IF_ERROR(U64(0, &extension_bits_[idx_extension]));
+ if (!SafeAdd(total_extension_bits_, extension_bits_[idx_extension],
+ total_extension_bits_)) {
+ return JXL_FAILURE("Extension bits overflowed, invalid codestream");
+ }
+ }
+ // Used by EndExtensions to skip past any _remaining_ extensions.
+ pos_after_ext_size_ = reader_->TotalBitsConsumed();
+ JXL_ASSERT(pos_after_ext_size_ != 0);
+ return true;
+ }
+
+ Status EndExtensions() override {
+ JXL_QUIET_RETURN_IF_ERROR(VisitorBase::EndExtensions());
+ // Happens if extensions == 0: don't read size, done.
+ if (pos_after_ext_size_ == 0) return true;
+
+ // Not enough bytes as set by BeginExtensions or earlier. Do not return
+ // this as a JXL_FAILURE or false (which can also propagate to error
+ // through e.g. JXL_RETURN_IF_ERROR), since this may be used while
+ // silently checking whether there are enough bytes. If this case must be
+ // treated as an error, reader_>Close() will do this, just like is already
+ // done for non-extension fields.
+ if (!enough_bytes_) return true;
+
+ // Skip new fields this (old?) decoder didn't know about, if any.
+ const size_t bits_read = reader_->TotalBitsConsumed();
+ uint64_t end;
+ if (!SafeAdd(pos_after_ext_size_, total_extension_bits_, end)) {
+ return JXL_FAILURE("Invalid extension size, caused overflow");
+ }
+ if (bits_read > end) {
+ return JXL_FAILURE("Read more extension bits than budgeted");
+ }
+ const size_t remaining_bits = end - bits_read;
+ if (remaining_bits != 0) {
+ JXL_WARNING("Skipping %" PRIuS "-bit extension(s)", remaining_bits);
+ reader_->SkipBits(remaining_bits);
+ if (!reader_->AllReadsWithinBounds()) {
+ return JXL_STATUS(StatusCode::kNotEnoughBytes,
+ "Not enough bytes for header");
+ }
+ }
+ return true;
+ }
+
+ Status OK() const { return ok_; }
+
+ private:
+ // Whether any error other than not enough bytes occurred.
+ bool ok_ = true;
+
+ // Whether there are enough input bytes to read from.
+ bool enough_bytes_ = true;
+ BitReader* const reader_;
+ // May be 0 even if the corresponding extension is present.
+ uint64_t extension_bits_[Bundle::kMaxExtensions] = {0};
+ uint64_t total_extension_bits_ = 0;
+ size_t pos_after_ext_size_ = 0; // 0 iff extensions == 0.
+};
+
+class MaxBitsVisitor : public VisitorBase {
+ public:
+ Status Bits(const size_t bits, const uint32_t /*default_value*/,
+ uint32_t* JXL_RESTRICT /*value*/) override {
+ max_bits_ += BitsCoder::MaxEncodedBits(bits);
+ return true;
+ }
+
+ Status U32(const U32Enc enc, const uint32_t /*default_value*/,
+ uint32_t* JXL_RESTRICT /*value*/) override {
+ max_bits_ += U32Coder::MaxEncodedBits(enc);
+ return true;
+ }
+
+ Status U64(const uint64_t /*default_value*/,
+ uint64_t* JXL_RESTRICT /*value*/) override {
+ max_bits_ += U64Coder::MaxEncodedBits();
+ return true;
+ }
+
+ Status F16(const float /*default_value*/,
+ float* JXL_RESTRICT /*value*/) override {
+ max_bits_ += F16Coder::MaxEncodedBits();
+ return true;
+ }
+
+ Status AllDefault(const Fields& /*fields*/,
+ bool* JXL_RESTRICT all_default) override {
+ JXL_RETURN_IF_ERROR(Bool(true, all_default));
+ return false; // For max bits, assume nothing is default
+ }
+
+ // Always visit conditional fields to get a (loose) upper bound.
+ Status Conditional(bool /*condition*/) override { return true; }
+
+ Status BeginExtensions(uint64_t* JXL_RESTRICT /*extensions*/) override {
+ // Skip - extensions are not included in "MaxBits" because their length
+ // is potentially unbounded.
+ return true;
+ }
+
+ Status EndExtensions() override { return true; }
+
+ size_t MaxBits() const { return max_bits_; }
+
+ private:
+ size_t max_bits_ = 0;
+};
+
+class CanEncodeVisitor : public VisitorBase {
+ public:
+ explicit CanEncodeVisitor() : VisitorBase() {}
+
+ Status Bits(const size_t bits, const uint32_t /*default_value*/,
+ uint32_t* JXL_RESTRICT value) override {
+ size_t encoded_bits = 0;
+ ok_ &= BitsCoder::CanEncode(bits, *value, &encoded_bits);
+ encoded_bits_ += encoded_bits;
+ return true;
+ }
+
+ Status U32(const U32Enc enc, const uint32_t /*default_value*/,
+ uint32_t* JXL_RESTRICT value) override {
+ size_t encoded_bits = 0;
+ ok_ &= U32Coder::CanEncode(enc, *value, &encoded_bits);
+ encoded_bits_ += encoded_bits;
+ return true;
+ }
+
+ Status U64(const uint64_t /*default_value*/,
+ uint64_t* JXL_RESTRICT value) override {
+ size_t encoded_bits = 0;
+ ok_ &= U64Coder::CanEncode(*value, &encoded_bits);
+ encoded_bits_ += encoded_bits;
+ return true;
+ }
+
+ Status F16(const float /*default_value*/,
+ float* JXL_RESTRICT value) override {
+ size_t encoded_bits = 0;
+ ok_ &= F16Coder::CanEncode(*value, &encoded_bits);
+ encoded_bits_ += encoded_bits;
+ return true;
+ }
+
+ Status AllDefault(const Fields& fields,
+ bool* JXL_RESTRICT all_default) override {
+ *all_default = Bundle::AllDefault(fields);
+ JXL_RETURN_IF_ERROR(Bool(true, all_default));
+ return *all_default;
+ }
+
+ Status BeginExtensions(uint64_t* JXL_RESTRICT extensions) override {
+ JXL_QUIET_RETURN_IF_ERROR(VisitorBase::BeginExtensions(extensions));
+ extensions_ = *extensions;
+ if (*extensions != 0) {
+ JXL_ASSERT(pos_after_ext_ == 0);
+ pos_after_ext_ = encoded_bits_;
+ JXL_ASSERT(pos_after_ext_ != 0); // visited "extensions"
+ }
+ return true;
+ }
+ // EndExtensions = default.
+
+ Status GetSizes(size_t* JXL_RESTRICT extension_bits,
+ size_t* JXL_RESTRICT total_bits) {
+ JXL_RETURN_IF_ERROR(ok_);
+ *extension_bits = 0;
+ *total_bits = encoded_bits_;
+ // Only if extension field was nonzero will we encode their sizes.
+ if (pos_after_ext_ != 0) {
+ JXL_ASSERT(encoded_bits_ >= pos_after_ext_);
+ *extension_bits = encoded_bits_ - pos_after_ext_;
+ // Also need to encode *extension_bits and bill it to *total_bits.
+ size_t encoded_bits = 0;
+ ok_ &= U64Coder::CanEncode(*extension_bits, &encoded_bits);
+ *total_bits += encoded_bits;
+
+ // TODO(janwas): support encoding individual extension sizes. We
+ // currently ascribe all bits to the first and send zeros for the
+ // others.
+ for (size_t i = 1; i < hwy::PopCount(extensions_); ++i) {
+ encoded_bits = 0;
+ ok_ &= U64Coder::CanEncode(0, &encoded_bits);
+ *total_bits += encoded_bits;
+ }
+ }
+ return true;
+ }
+
+ private:
+ bool ok_ = true;
+ size_t encoded_bits_ = 0;
+ uint64_t extensions_ = 0;
+ // Snapshot of encoded_bits_ after visiting the extension field, but NOT
+ // including the hidden extension sizes.
+ uint64_t pos_after_ext_ = 0;
+};
+} // namespace
+
+void Bundle::Init(Fields* fields) {
+ InitVisitor visitor;
+ if (!visitor.Visit(fields)) {
+ JXL_ABORT("Init should never fail");
+ }
+}
+void Bundle::SetDefault(Fields* fields) {
+ SetDefaultVisitor visitor;
+ if (!visitor.Visit(fields)) {
+ JXL_ABORT("SetDefault should never fail");
+ }
+}
+bool Bundle::AllDefault(const Fields& fields) {
+ AllDefaultVisitor visitor;
+ if (!visitor.VisitConst(fields)) {
+ JXL_ABORT("AllDefault should never fail");
+ }
+ return visitor.AllDefault();
+}
+size_t Bundle::MaxBits(const Fields& fields) {
+ MaxBitsVisitor visitor;
+#if JXL_ENABLE_ASSERT
+ Status ret =
+#else
+ (void)
+#endif // JXL_ENABLE_ASSERT
+ visitor.VisitConst(fields);
+ JXL_ASSERT(ret);
+ return visitor.MaxBits();
+}
+Status Bundle::CanEncode(const Fields& fields, size_t* extension_bits,
+ size_t* total_bits) {
+ CanEncodeVisitor visitor;
+ JXL_QUIET_RETURN_IF_ERROR(visitor.VisitConst(fields));
+ JXL_QUIET_RETURN_IF_ERROR(visitor.GetSizes(extension_bits, total_bits));
+ return true;
+}
+Status Bundle::Read(BitReader* reader, Fields* fields) {
+ ReadVisitor visitor(reader);
+ JXL_RETURN_IF_ERROR(visitor.Visit(fields));
+ return visitor.OK();
+}
+bool Bundle::CanRead(BitReader* reader, Fields* fields) {
+ ReadVisitor visitor(reader);
+ Status status = visitor.Visit(fields);
+ // We are only checking here whether there are enough bytes. We still return
+ // true for other errors because it means there are enough bytes to determine
+ // there's an error. Use Read() to determine which error it is.
+ return status.code() != StatusCode::kNotEnoughBytes;
+}
+
+size_t BitsCoder::MaxEncodedBits(const size_t bits) { return bits; }
+
+Status BitsCoder::CanEncode(const size_t bits, const uint32_t value,
+ size_t* JXL_RESTRICT encoded_bits) {
+ *encoded_bits = bits;
+ if (value >= (1ULL << bits)) {
+ return JXL_FAILURE("Value %u too large for %" PRIu64 " bits", value,
+ static_cast<uint64_t>(bits));
+ }
+ return true;
+}
+
+uint32_t BitsCoder::Read(const size_t bits, BitReader* JXL_RESTRICT reader) {
+ return reader->ReadBits(bits);
+}
+
+size_t U32Coder::MaxEncodedBits(const U32Enc enc) {
+ size_t extra_bits = 0;
+ for (uint32_t selector = 0; selector < 4; ++selector) {
+ const U32Distr d = enc.GetDistr(selector);
+ if (d.IsDirect()) {
+ continue;
+ } else {
+ extra_bits = std::max<size_t>(extra_bits, d.ExtraBits());
+ }
+ }
+ return 2 + extra_bits;
+}
+
+Status U32Coder::CanEncode(const U32Enc enc, const uint32_t value,
+ size_t* JXL_RESTRICT encoded_bits) {
+ uint32_t selector;
+ size_t total_bits;
+ const Status ok = ChooseSelector(enc, value, &selector, &total_bits);
+ *encoded_bits = ok ? total_bits : 0;
+ return ok;
+}
+
+uint32_t U32Coder::Read(const U32Enc enc, BitReader* JXL_RESTRICT reader) {
+ const uint32_t selector = reader->ReadFixedBits<2>();
+ const U32Distr d = enc.GetDistr(selector);
+ if (d.IsDirect()) {
+ return d.Direct();
+ } else {
+ return reader->ReadBits(d.ExtraBits()) + d.Offset();
+ }
+}
+
+Status U32Coder::ChooseSelector(const U32Enc enc, const uint32_t value,
+ uint32_t* JXL_RESTRICT selector,
+ size_t* JXL_RESTRICT total_bits) {
+#if JXL_ENABLE_ASSERT
+ const size_t bits_required = 32 - Num0BitsAboveMS1Bit(value);
+#endif // JXL_ENABLE_ASSERT
+ JXL_ASSERT(bits_required <= 32);
+
+ *selector = 0;
+ *total_bits = 0;
+
+ // It is difficult to verify whether Dist32Byte are sorted, so check all
+ // selectors and keep the one with the fewest total_bits.
+ *total_bits = 64; // more than any valid encoding
+ for (uint32_t s = 0; s < 4; ++s) {
+ const U32Distr d = enc.GetDistr(s);
+ if (d.IsDirect()) {
+ if (d.Direct() == value) {
+ *selector = s;
+ *total_bits = 2;
+ return true; // Done, direct is always the best possible.
+ }
+ continue;
+ }
+ const size_t extra_bits = d.ExtraBits();
+ const uint32_t offset = d.Offset();
+ if (value < offset || value >= offset + (1ULL << extra_bits)) continue;
+
+ // Better than prior encoding, remember it:
+ if (2 + extra_bits < *total_bits) {
+ *selector = s;
+ *total_bits = 2 + extra_bits;
+ }
+ }
+
+ if (*total_bits == 64) {
+ return JXL_FAILURE("No feasible selector for %u", value);
+ }
+
+ return true;
+}
+
+uint64_t U64Coder::Read(BitReader* JXL_RESTRICT reader) {
+ uint64_t selector = reader->ReadFixedBits<2>();
+ if (selector == 0) {
+ return 0;
+ }
+ if (selector == 1) {
+ return 1 + reader->ReadFixedBits<4>();
+ }
+ if (selector == 2) {
+ return 17 + reader->ReadFixedBits<8>();
+ }
+
+ // selector 3, varint, groups have first 12, then 8, and last 4 bits.
+ uint64_t result = reader->ReadFixedBits<12>();
+
+ uint64_t shift = 12;
+ while (reader->ReadFixedBits<1>()) {
+ if (shift == 60) {
+ result |= static_cast<uint64_t>(reader->ReadFixedBits<4>()) << shift;
+ break;
+ }
+ result |= static_cast<uint64_t>(reader->ReadFixedBits<8>()) << shift;
+ shift += 8;
+ }
+
+ return result;
+}
+
+// Can always encode, but useful because it also returns bit size.
+Status U64Coder::CanEncode(uint64_t value, size_t* JXL_RESTRICT encoded_bits) {
+ if (value == 0) {
+ *encoded_bits = 2; // 2 selector bits
+ } else if (value <= 16) {
+ *encoded_bits = 2 + 4; // 2 selector bits + 4 payload bits
+ } else if (value <= 272) {
+ *encoded_bits = 2 + 8; // 2 selector bits + 8 payload bits
+ } else {
+ *encoded_bits = 2 + 12; // 2 selector bits + 12 payload bits
+ value >>= 12;
+ int shift = 12;
+ while (value > 0 && shift < 60) {
+ *encoded_bits += 1 + 8; // 1 continuation bit + 8 payload bits
+ value >>= 8;
+ shift += 8;
+ }
+ if (value > 0) {
+ // This only could happen if shift == N - 4.
+ *encoded_bits += 1 + 4; // 1 continuation bit + 4 payload bits
+ } else {
+ *encoded_bits += 1; // 1 stop bit
+ }
+ }
+
+ return true;
+}
+
+Status F16Coder::Read(BitReader* JXL_RESTRICT reader,
+ float* JXL_RESTRICT value) {
+ const uint32_t bits16 = reader->ReadFixedBits<16>();
+ const uint32_t sign = bits16 >> 15;
+ const uint32_t biased_exp = (bits16 >> 10) & 0x1F;
+ const uint32_t mantissa = bits16 & 0x3FF;
+
+ if (JXL_UNLIKELY(biased_exp == 31)) {
+ return JXL_FAILURE("F16 infinity or NaN are not supported");
+ }
+
+ // Subnormal or zero
+ if (JXL_UNLIKELY(biased_exp == 0)) {
+ *value = (1.0f / 16384) * (mantissa * (1.0f / 1024));
+ if (sign) *value = -*value;
+ return true;
+ }
+
+ // Normalized: convert the representation directly (faster than ldexp/tables).
+ const uint32_t biased_exp32 = biased_exp + (127 - 15);
+ const uint32_t mantissa32 = mantissa << (23 - 10);
+ const uint32_t bits32 = (sign << 31) | (biased_exp32 << 23) | mantissa32;
+ memcpy(value, &bits32, sizeof(bits32));
+ return true;
+}
+
+Status F16Coder::CanEncode(float value, size_t* JXL_RESTRICT encoded_bits) {
+ *encoded_bits = MaxEncodedBits();
+ if (std::isnan(value) || std::isinf(value)) {
+ return JXL_FAILURE("Should not attempt to store NaN and infinity");
+ }
+ return std::abs(value) <= 65504.0f;
+}
+
+} // namespace jxl