1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
|
// 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_
|
