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diff --git a/third_party/jpeg-xl/lib/jxl/dec_xyb.h b/third_party/jpeg-xl/lib/jxl/dec_xyb.h
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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.
+
+#ifndef LIB_JXL_DEC_XYB_H_
+#define LIB_JXL_DEC_XYB_H_
+
+// XYB -> linear sRGB.
+
+#include "lib/jxl/base/compiler_specific.h"
+#include "lib/jxl/base/data_parallel.h"
+#include "lib/jxl/base/status.h"
+#include "lib/jxl/color_encoding_internal.h"
+#include "lib/jxl/dec_bit_reader.h"
+#include "lib/jxl/image.h"
+#include "lib/jxl/image_metadata.h"
+#include "lib/jxl/opsin_params.h"
+
+namespace jxl {
+
+// Parameters for XYB->sRGB conversion.
+struct OpsinParams {
+  float inverse_opsin_matrix[9 * 4];
+  float opsin_biases[4];
+  float opsin_biases_cbrt[4];
+  float quant_biases[4];
+  void Init(float intensity_target);
+};
+
+struct OutputEncodingInfo {
+  //
+  // Fields depending only on image metadata
+  //
+  ColorEncoding orig_color_encoding;
+  // Used for the HLG OOTF and PQ tone mapping.
+  float orig_intensity_target;
+  // Opsin inverse matrix taken from the metadata.
+  float orig_inverse_matrix[9];
+  bool default_transform;
+  bool xyb_encoded;
+  //
+  // Fields depending on output color encoding
+  //
+  ColorEncoding color_encoding;
+  bool color_encoding_is_original;
+  // Contains an opsin matrix that converts to the primaries of the output
+  // encoding.
+  OpsinParams opsin_params;
+  bool all_default_opsin;
+  // Used for Gamma and DCI transfer functions.
+  float inverse_gamma;
+  // Luminances of color_encoding's primaries, used for the HLG inverse OOTF and
+  // for PQ tone mapping.
+  // Default to sRGB's.
+  float luminances[3];
+  // Used for the HLG inverse OOTF and PQ tone mapping.
+  float desired_intensity_target;
+
+  Status SetFromMetadata(const CodecMetadata& metadata);
+  Status MaybeSetColorEncoding(const ColorEncoding& c_desired);
+
+ private:
+  Status SetColorEncoding(const ColorEncoding& c_desired);
+};
+
+// Converts `inout` (not padded) from opsin to linear sRGB in-place. Called from
+// per-pass postprocessing, hence parallelized.
+void OpsinToLinearInplace(Image3F* JXL_RESTRICT inout, ThreadPool* pool,
+                          const OpsinParams& opsin_params);
+
+// Converts `opsin:rect` (opsin may be padded, rect.x0 must be vector-aligned)
+// to linear sRGB. Called from whole-frame encoder, hence parallelized.
+void OpsinToLinear(const Image3F& opsin, const Rect& rect, ThreadPool* pool,
+                   Image3F* JXL_RESTRICT linear,
+                   const OpsinParams& opsin_params);
+
+// Bt.601 to match JPEG/JFIF. Inputs are _signed_ YCbCr values suitable for DCT,
+// see F.1.1.3 of T.81 (because our data type is float, there is no need to add
+// a bias to make the values unsigned).
+void YcbcrToRgb(const Image3F& ycbcr, Image3F* rgb, const Rect& rect);
+
+bool HasFastXYBTosRGB8();
+void FastXYBTosRGB8(const float* input[4], uint8_t* output, bool is_rgba,
+                    size_t xsize);
+
+}  // namespace jxl
+
+#endif  // LIB_JXL_DEC_XYB_H_