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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/image_bundle.h"
#include <utility>
#include "lib/jxl/base/printf_macros.h"
#include "lib/jxl/base/status.h"
#include "lib/jxl/image.h"
namespace jxl {
Status ImageBundle::ShrinkTo(size_t xsize, size_t ysize) {
if (HasColor()) {
JXL_RETURN_IF_ERROR(color_.ShrinkTo(xsize, ysize));
}
for (ImageF& ec : extra_channels_) {
JXL_RETURN_IF_ERROR(ec.ShrinkTo(xsize, ysize));
}
return true;
}
// Called by all other SetFrom*.
Status ImageBundle::SetFromImage(Image3F&& color,
const ColorEncoding& c_current) {
JXL_ENSURE(color.xsize() != 0 && color.ysize() != 0);
JXL_ENSURE(metadata_->color_encoding.IsGray() == c_current.IsGray());
color_ = std::move(color);
c_current_ = c_current;
JXL_RETURN_IF_ERROR(VerifySizes());
return true;
}
Status ImageBundle::VerifyMetadata() const {
JXL_ENSURE(!c_current_.ICC().empty());
JXL_ENSURE(metadata_->color_encoding.IsGray() == IsGray());
if (metadata_->HasAlpha()) {
const ImageF* a = alpha();
if (a->xsize() == 0) {
return JXL_UNREACHABLE("MD alpha_bits %u IB alpha %" PRIuS " x %" PRIuS
"\n",
metadata_->GetAlphaBits(), a->xsize(), a->ysize());
}
}
const uint32_t alpha_bits = metadata_->GetAlphaBits();
JXL_ENSURE(alpha_bits <= 32);
// metadata_->num_extra_channels may temporarily differ from
// extra_channels_.size(), e.g. after SetAlpha. They are synced by the next
// call to VisitFields.
return true;
}
Status ImageBundle::VerifySizes() const {
const size_t xs = xsize();
const size_t ys = ysize();
if (HasExtraChannels()) {
JXL_ENSURE(xs != 0 && ys != 0);
for (const ImageF& ec : extra_channels_) {
JXL_ENSURE(ec.xsize() == xs);
JXL_ENSURE(ec.ysize() == ys);
}
}
return true;
}
size_t ImageBundle::DetectRealBitdepth() const {
return metadata_->bit_depth.bits_per_sample;
// TODO(lode): let this function return lower bit depth if possible, e.g.
// return 8 bits in case the original image came from a 16-bit PNG that
// was in fact representable as 8-bit PNG. Ensure that the implementation
// returns 16 if e.g. two consecutive 16-bit values appeared in the original
// image (such as 32768 and 32769), take into account that e.g. the values
// 3-bit can represent is not a superset of the values 2-bit can represent,
// and there may be slight imprecisions in the floating point image.
}
const ImageF* ImageBundle::black() const {
if (!HasBlack()) return nullptr;
const size_t ec = metadata_->Find(ExtraChannel::kBlack) -
metadata_->extra_channel_info.data();
JXL_DASSERT(ec < extra_channels_.size());
return &extra_channels_[ec];
}
const ImageF* ImageBundle::alpha() const {
if (!HasAlpha()) return nullptr;
const size_t ec = metadata_->Find(ExtraChannel::kAlpha) -
metadata_->extra_channel_info.data();
JXL_DASSERT(ec < extra_channels_.size());
return &extra_channels_[ec];
}
ImageF* ImageBundle::alpha() {
if (!HasAlpha()) return nullptr;
const size_t ec = metadata_->Find(ExtraChannel::kAlpha) -
metadata_->extra_channel_info.data();
JXL_DASSERT(ec < extra_channels_.size());
return &extra_channels_[ec];
}
Status ImageBundle::SetAlpha(ImageF&& alpha) {
const ExtraChannelInfo* eci = metadata_->Find(ExtraChannel::kAlpha);
// Must call SetAlphaBits first, otherwise we don't know which channel index
JXL_ENSURE(eci != nullptr);
JXL_ENSURE(alpha.xsize() != 0 && alpha.ysize() != 0);
if (extra_channels_.size() < metadata_->extra_channel_info.size()) {
// TODO(jon): get rid of this case
extra_channels_.insert(
extra_channels_.begin() + (eci - metadata_->extra_channel_info.data()),
std::move(alpha));
} else {
extra_channels_[eci - metadata_->extra_channel_info.data()] =
std::move(alpha);
}
// num_extra_channels is automatically set in visitor
JXL_RETURN_IF_ERROR(VerifySizes());
return true;
}
Status ImageBundle::SetExtraChannels(std::vector<ImageF>&& extra_channels) {
for (const ImageF& plane : extra_channels) {
JXL_ENSURE(plane.xsize() != 0 && plane.ysize() != 0);
}
extra_channels_ = std::move(extra_channels);
JXL_RETURN_IF_ERROR(VerifySizes());
return true;
}
} // namespace jxl