The Battle for Wesnoth  1.19.6+dev
xbrz.hpp
Go to the documentation of this file.
1 // ****************************************************************************
2 // * This file is part of the xBRZ project. It is distributed under *
3 // * GNU General Public License: https://www.gnu.org/licenses/gpl-3.0 *
4 // * Copyright (C) Zenju (zenju AT gmx DOT de) - All Rights Reserved *
5 // * *
6 // * Additionally and as a special exception, the author gives permission *
7 // * to link the code of this program with the following libraries *
8 // * (or with modified versions that use the same licenses), and distribute *
9 // * linked combinations including the two: MAME, FreeFileSync, Snes9x, ePSXe *
10 // * You must obey the GNU General Public License in all respects for all of *
11 // * the code used other than MAME, FreeFileSync, Snes9x, ePSXe. *
12 // * If you modify this file, you may extend this exception to your version *
13 // * of the file, but you are not obligated to do so. If you do not wish to *
14 // * do so, delete this exception statement from your version. *
15 // ****************************************************************************
16 
17 #ifndef XBRZ_HEADER_3847894708239054
18 #define XBRZ_HEADER_3847894708239054
19 
20 #include <cstddef> //size_t
21 #include <cstdint> //uint32_t
22 #include <limits>
23 #include "xbrz_config.hpp"
24 
25 
26 namespace xbrz
27 {
28 /*
29 -------------------------------------------------------------------------
30 | xBRZ: "Scale by rules" - high quality image upscaling filter by Zenju |
31 -------------------------------------------------------------------------
32 using a modified approach of xBR:
33 http://board.byuu.org/viewtopic.php?f=10&t=2248
34 - new rule set preserving small image features
35 - highly optimized for performance
36 - support alpha channel
37 - support multithreading
38 - support 64-bit architectures
39 - support processing image slices
40 - support scaling up to 6xBRZ
41 */
42 
43 enum class ColorFormat //from high bits -> low bits, 8 bit per channel
44 {
45  RGB, //8 bit for each red, green, blue, upper 8 bits unused
46  ARGB, //including alpha channel, BGRA byte order on little-endian machines
47  ARGB_UNBUFFERED, //like ARGB, but without the one-time buffer creation overhead (ca. 100 - 300 ms) at the expense of a slightly slower scaling time
48 };
49 
50 const int SCALE_FACTOR_MAX = 6;
51 
52 /*
53 -> map source (srcWidth * srcHeight) to target (scale * width x scale * height) image, optionally processing a half-open slice of rows [yFirst, yLast) only
54 -> if your emulator changes only a few image slices during each cycle (e.g. DOSBox) then there's no need to run xBRZ on the complete image:
55  Just make sure you enlarge the source image slice by 2 rows on top and 2 on bottom (this is the additional range the xBRZ algorithm is using during analysis)
56  CAVEAT: If there are multiple changed slices, make sure they do not overlap after adding these additional rows in order to avoid a memory race condition
57  in the target image data if you are using multiple threads for processing each enlarged slice!
58 
59 THREAD-SAFETY: - parts of the same image may be scaled by multiple threads as long as the [yFirst, yLast) ranges do not overlap!
60  - there is a minor inefficiency for the first row of a slice, so avoid processing single rows only; suggestion: process at least 8-16 rows
61 */
62 void scale(size_t factor, //valid range: 2 - SCALE_FACTOR_MAX
63  const uint32_t* src, uint32_t* trg, int srcWidth, int srcHeight,
64  ColorFormat colFmt,
65  const ScalerCfg& cfg = ScalerCfg(),
66  int yFirst = 0, int yLast = std::numeric_limits<int>::max()); //slice of source image
67 
68 void bilinearScale(const uint32_t* src, int srcWidth, int srcHeight,
69  /**/ uint32_t* trg, int trgWidth, int trgHeight);
70 
71 void nearestNeighborScale(const uint32_t* src, int srcWidth, int srcHeight,
72  /**/ uint32_t* trg, int trgWidth, int trgHeight);
73 
74 
75 //parameter tuning
76 bool equalColorTest(uint32_t col1, uint32_t col2, ColorFormat colFmt, double luminanceWeight, double equalColorTolerance);
77 }
78 
79 #endif
Definition: xbrz.hpp:27
void scale(size_t factor, const uint32_t *src, uint32_t *trg, int srcWidth, int srcHeight, ColorFormat colFmt, const ScalerCfg &cfg=ScalerCfg(), int yFirst=0, int yLast=std::numeric_limits< int >::max())
Definition: xbrz.cpp:1170
bool equalColorTest(uint32_t col1, uint32_t col2, ColorFormat colFmt, double luminanceWeight, double equalColorTolerance)
Definition: xbrz.cpp:1233
void nearestNeighborScale(const uint32_t *src, int srcWidth, int srcHeight, uint32_t *trg, int trgWidth, int trgHeight)
Definition: xbrz.cpp:1258
const int SCALE_FACTOR_MAX
Definition: xbrz.hpp:50
void bilinearScale(const uint32_t *src, int srcWidth, int srcHeight, uint32_t *trg, int trgWidth, int trgHeight)
Definition: xbrz.cpp:1249
ColorFormat
Definition: xbrz.hpp:44
rect src
Non-transparent portion of the surface to compose.