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// 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/headers.h"
#include "lib/jxl/fields.h"
#include "lib/jxl/frame_dimensions.h"
namespace jxl {
namespace {
struct Rational {
constexpr explicit Rational(uint32_t num, uint32_t den)
: num(num), den(den) {}
// Returns floor(multiplicand * rational).
constexpr uint32_t MulTruncate(uint32_t multiplicand) const {
return static_cast<uint64_t>(multiplicand) * num / den;
}
uint32_t num;
uint32_t den;
};
Rational FixedAspectRatios(uint32_t ratio) {
JXL_DASSERT(0 != ratio && ratio < 8);
// Other candidates: 5/4, 7/5, 14/9, 16/10, 5/3, 21/9, 12/5
constexpr Rational kRatios[7] = {Rational(1, 1), // square
Rational(12, 10), //
Rational(4, 3), // camera
Rational(3, 2), // mobile camera
Rational(16, 9), // camera/display
Rational(5, 4), //
Rational(2, 1)}; //
return kRatios[ratio - 1];
}
uint32_t FindAspectRatio(uint32_t xsize, uint32_t ysize) {
for (uint32_t r = 1; r < 8; ++r) {
if (xsize == FixedAspectRatios(r).MulTruncate(ysize)) {
return r;
}
}
return 0; // Must send xsize instead
}
} // namespace
size_t SizeHeader::xsize() const {
if (ratio_ != 0) {
return FixedAspectRatios(ratio_).MulTruncate(
static_cast<uint32_t>(ysize()));
}
return small_ ? ((xsize_div8_minus_1_ + 1) * 8) : xsize_;
}
Status SizeHeader::Set(size_t xsize64, size_t ysize64) {
if (xsize64 > 0xFFFFFFFFull || ysize64 > 0xFFFFFFFFull) {
return JXL_FAILURE("Image too large");
}
const uint32_t xsize32 = static_cast<uint32_t>(xsize64);
const uint32_t ysize32 = static_cast<uint32_t>(ysize64);
if (xsize64 == 0 || ysize64 == 0) return JXL_FAILURE("Empty image");
ratio_ = FindAspectRatio(xsize32, ysize32);
small_ = ysize64 <= 256 && (ysize64 % kBlockDim) == 0 &&
(ratio_ != 0 || (xsize64 <= 256 && (xsize64 % kBlockDim) == 0));
if (small_) {
ysize_div8_minus_1_ = ysize32 / 8 - 1;
} else {
ysize_ = ysize32;
}
if (ratio_ == 0) {
if (small_) {
xsize_div8_minus_1_ = xsize32 / 8 - 1;
} else {
xsize_ = xsize32;
}
}
JXL_ENSURE(xsize() == xsize64);
JXL_ENSURE(ysize() == ysize64);
return true;
}
Status PreviewHeader::Set(size_t xsize64, size_t ysize64) {
const uint32_t xsize32 = static_cast<uint32_t>(xsize64);
const uint32_t ysize32 = static_cast<uint32_t>(ysize64);
if (xsize64 == 0 || ysize64 == 0) return JXL_FAILURE("Empty preview");
div8_ = (xsize64 % kBlockDim) == 0 && (ysize64 % kBlockDim) == 0;
if (div8_) {
ysize_div8_ = ysize32 / 8;
} else {
ysize_ = ysize32;
}
ratio_ = FindAspectRatio(xsize32, ysize32);
if (ratio_ == 0) {
if (div8_) {
xsize_div8_ = xsize32 / 8;
} else {
xsize_ = xsize32;
}
}
JXL_ENSURE(xsize() == xsize64);
JXL_ENSURE(ysize() == ysize64);
return true;
}
size_t PreviewHeader::xsize() const {
if (ratio_ != 0) {
return FixedAspectRatios(ratio_).MulTruncate(
static_cast<uint32_t>(ysize()));
}
return div8_ ? (xsize_div8_ * 8) : xsize_;
}
SizeHeader::SizeHeader() { Bundle::Init(this); }
Status SizeHeader::VisitFields(Visitor* JXL_RESTRICT visitor) {
JXL_QUIET_RETURN_IF_ERROR(visitor->Bool(false, &small_));
if (visitor->Conditional(small_)) {
JXL_QUIET_RETURN_IF_ERROR(visitor->Bits(5, 0, &ysize_div8_minus_1_));
}
if (visitor->Conditional(!small_)) {
// (Could still be small, but non-multiple of 8.)
JXL_QUIET_RETURN_IF_ERROR(visitor->U32(BitsOffset(9, 1), BitsOffset(13, 1),
BitsOffset(18, 1), BitsOffset(30, 1),
1, &ysize_));
}
JXL_QUIET_RETURN_IF_ERROR(visitor->Bits(3, 0, &ratio_));
if (visitor->Conditional(ratio_ == 0 && small_)) {
JXL_QUIET_RETURN_IF_ERROR(visitor->Bits(5, 0, &xsize_div8_minus_1_));
}
if (visitor->Conditional(ratio_ == 0 && !small_)) {
JXL_QUIET_RETURN_IF_ERROR(visitor->U32(BitsOffset(9, 1), BitsOffset(13, 1),
BitsOffset(18, 1), BitsOffset(30, 1),
1, &xsize_));
}
return true;
}
PreviewHeader::PreviewHeader() { Bundle::Init(this); }
Status PreviewHeader::VisitFields(Visitor* JXL_RESTRICT visitor) {
JXL_QUIET_RETURN_IF_ERROR(visitor->Bool(false, &div8_));
if (visitor->Conditional(div8_)) {
JXL_QUIET_RETURN_IF_ERROR(visitor->U32(Val(16), Val(32), BitsOffset(5, 1),
BitsOffset(9, 33), 1, &ysize_div8_));
}
if (visitor->Conditional(!div8_)) {
JXL_QUIET_RETURN_IF_ERROR(visitor->U32(BitsOffset(6, 1), BitsOffset(8, 65),
BitsOffset(10, 321),
BitsOffset(12, 1345), 1, &ysize_));
}
JXL_QUIET_RETURN_IF_ERROR(visitor->Bits(3, 0, &ratio_));
if (visitor->Conditional(ratio_ == 0 && div8_)) {
JXL_QUIET_RETURN_IF_ERROR(visitor->U32(Val(16), Val(32), BitsOffset(5, 1),
BitsOffset(9, 33), 1, &xsize_div8_));
}
if (visitor->Conditional(ratio_ == 0 && !div8_)) {
JXL_QUIET_RETURN_IF_ERROR(visitor->U32(BitsOffset(6, 1), BitsOffset(8, 65),
BitsOffset(10, 321),
BitsOffset(12, 1345), 1, &xsize_));
}
return true;
}
AnimationHeader::AnimationHeader() { Bundle::Init(this); }
Status AnimationHeader::VisitFields(Visitor* JXL_RESTRICT visitor) {
JXL_QUIET_RETURN_IF_ERROR(visitor->U32(Val(100), Val(1000), BitsOffset(10, 1),
BitsOffset(30, 1), 1, &tps_numerator));
JXL_QUIET_RETURN_IF_ERROR(visitor->U32(Val(1), Val(1001), BitsOffset(8, 1),
BitsOffset(10, 1), 1,
&tps_denominator));
JXL_QUIET_RETURN_IF_ERROR(
visitor->U32(Val(0), Bits(3), Bits(16), Bits(32), 0, &num_loops));
JXL_QUIET_RETURN_IF_ERROR(visitor->Bool(false, &have_timecodes));
return true;
}
Status ReadSizeHeader(BitReader* JXL_RESTRICT reader,
SizeHeader* JXL_RESTRICT size) {
return Bundle::Read(reader, size);
}
} // namespace jxl