ladybird/Userland/Libraries/LibGfx/ImageFormats/TIFFLoader.h
Lucas CHOLLET f6f647bf13 LibGfx/TIFF: Add an alternative entry point to only request metadata
A lot of images format use Exif to store there metadata. As Exif is
based on the TIFF structure, the TIFF decoder can, without modification
be able to decode the metadata. We only need a new API to explicitly
mention that we only need the metadata.
2024-01-22 20:16:32 -07:00

57 lines
1.7 KiB
C++

/*
* Copyright (c) 2023, Lucas Chollet <lucas.chollet@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/MemoryStream.h>
#include <AK/NonnullOwnPtr.h>
#include <LibGfx/ImageFormats/ImageDecoder.h>
namespace Gfx {
class ExifMetadata;
// This is a link to the main TIFF specification from 1992
// https://www.itu.int/itudoc/itu-t/com16/tiff-fx/docs/tiff6.pdf
// First TIFF Technical notes from 1995
// https://www.awaresystems.be/imaging/tiff/specification/TIFFPM6.pdf
// Second TIFF Technical notes from 1995
// The document is the second (and current) specification for embedded JPEGs in TIFF images.
// https://www.awaresystems.be/imaging/tiff/specification/TIFFTechNote2.txt
// This is also compatible with Exif as it is, basically, another set of TIFF tags:
// The spec is named "Exchangeable image file format for digital still cameras: Exif Version 3.0"
// And it can be found at https://www.cipa.jp/e/std/std-sec.html
namespace TIFF {
class TIFFLoadingContext;
}
class TIFFImageDecoderPlugin : public ImageDecoderPlugin {
public:
static bool sniff(ReadonlyBytes);
static ErrorOr<NonnullOwnPtr<ImageDecoderPlugin>> create(ReadonlyBytes);
static ErrorOr<NonnullOwnPtr<ExifMetadata>> read_exif_metadata(ReadonlyBytes);
virtual ~TIFFImageDecoderPlugin() override = default;
virtual IntSize size() override;
virtual ErrorOr<ImageFrameDescriptor> frame(size_t index, Optional<IntSize> ideal_size = {}) override;
virtual Optional<Metadata const&> metadata() override;
virtual ErrorOr<Optional<ReadonlyBytes>> icc_data() override;
private:
TIFFImageDecoderPlugin(NonnullOwnPtr<FixedMemoryStream>);
OwnPtr<TIFF::TIFFLoadingContext> m_context;
};
}