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92f5a8d4 TL |
1 | // |
2 | // Copyright 2005-2007 Adobe Systems Incorporated | |
3 | // Copyright 2019 Mateusz Loskot <mateusz at loskot dot net> | |
4 | // | |
5 | // Distributed under the Boost Software License, Version 1.0 | |
6 | // See accompanying file LICENSE_1_0.txt or copy at | |
7 | // http://www.boost.org/LICENSE_1_0.txt | |
8 | // | |
9 | #ifndef BOOST_GIL_BIT_ALIGNED_PIXEL_REFERENCE_HPP | |
10 | #define BOOST_GIL_BIT_ALIGNED_PIXEL_REFERENCE_HPP | |
11 | ||
12 | #include <boost/gil/pixel.hpp> | |
13 | #include <boost/gil/channel.hpp> | |
14 | #include <boost/gil/detail/mp11.hpp> | |
15 | ||
16 | #include <boost/assert.hpp> | |
17 | #include <boost/config.hpp> | |
7c673cae FG |
18 | |
19 | #include <functional> | |
92f5a8d4 | 20 | #include <type_traits> |
7c673cae FG |
21 | |
22 | namespace boost { namespace gil { | |
23 | ||
92f5a8d4 TL |
24 | /// A model of a heterogeneous pixel that is not byte aligned. |
25 | /// Examples are bitmap (1-bit pixels) or 6-bit RGB (222). | |
26 | ||
7c673cae FG |
27 | ///////////////////////////// |
28 | // bit_range | |
29 | // | |
30 | // Represents a range of bits that can span multiple consecutive bytes. The range has a size fixed at compile time, but the offset is specified at run time. | |
31 | ///////////////////////////// | |
92f5a8d4 TL |
32 | |
33 | template <int RangeSize, bool IsMutable> | |
7c673cae FG |
34 | class bit_range { |
35 | public: | |
92f5a8d4 TL |
36 | using byte_t = mp11::mp_if_c<IsMutable, unsigned char, unsigned char const>; |
37 | using difference_type = std::ptrdiff_t; | |
7c673cae FG |
38 | template <int RS, bool M> friend class bit_range; |
39 | private: | |
40 | byte_t* _current_byte; // the starting byte of the bit range | |
41 | int _bit_offset; // offset from the beginning of the current byte. 0<=_bit_offset<=7 | |
42 | ||
43 | public: | |
92f5a8d4 TL |
44 | bit_range() : _current_byte(nullptr), _bit_offset(0) {} |
45 | bit_range(byte_t* current_byte, int bit_offset) | |
46 | : _current_byte(current_byte) | |
47 | , _bit_offset(bit_offset) | |
48 | { | |
49 | BOOST_ASSERT(bit_offset >= 0 && bit_offset < 8); | |
50 | } | |
7c673cae FG |
51 | |
52 | bit_range(const bit_range& br) : _current_byte(br._current_byte), _bit_offset(br._bit_offset) {} | |
53 | template <bool M> bit_range(const bit_range<RangeSize,M>& br) : _current_byte(br._current_byte), _bit_offset(br._bit_offset) {} | |
54 | ||
55 | bit_range& operator=(const bit_range& br) { _current_byte = br._current_byte; _bit_offset=br._bit_offset; return *this; } | |
56 | bool operator==(const bit_range& br) const { return _current_byte==br._current_byte && _bit_offset==br._bit_offset; } | |
57 | ||
58 | bit_range& operator++() { | |
59 | _current_byte += (_bit_offset+RangeSize) / 8; | |
60 | _bit_offset = (_bit_offset+RangeSize) % 8; | |
61 | return *this; | |
62 | } | |
63 | bit_range& operator--() { bit_advance(-RangeSize); return *this; } | |
64 | ||
65 | void bit_advance(difference_type num_bits) { | |
66 | int new_offset = int(_bit_offset+num_bits); | |
67 | _current_byte += new_offset / 8; | |
68 | _bit_offset = new_offset % 8; | |
69 | if (_bit_offset<0) { | |
70 | _bit_offset+=8; | |
71 | --_current_byte; | |
72 | } | |
73 | } | |
74 | difference_type bit_distance_to(const bit_range& b) const { | |
75 | return (b.current_byte() - current_byte())*8 + b.bit_offset()-bit_offset(); | |
76 | } | |
77 | byte_t* current_byte() const { return _current_byte; } | |
78 | int bit_offset() const { return _bit_offset; } | |
79 | }; | |
80 | ||
92f5a8d4 | 81 | /// \defgroup ColorBaseModelNonAlignedPixel bit_aligned_pixel_reference |
7c673cae FG |
82 | /// \ingroup ColorBaseModel |
83 | /// \brief A heterogeneous color base representing pixel that may not be byte aligned, i.e. it may correspond to a bit range that does not start/end at a byte boundary. Models ColorBaseConcept. | |
92f5a8d4 TL |
84 | /// |
85 | /// \defgroup PixelModelNonAlignedPixel bit_aligned_pixel_reference | |
86 | /// \ingroup PixelModel | |
87 | /// \brief A heterogeneous pixel reference used to represent non-byte-aligned pixels. Models PixelConcept | |
88 | /// | |
89 | /// Example: | |
90 | /// \code | |
91 | /// unsigned char data=0; | |
92 | /// | |
93 | /// // A mutable reference to a 6-bit BGR pixel in "123" format (1 bit for red, 2 bits for green, 3 bits for blue) | |
94 | /// using rgb123_ref_t = bit_aligned_pixel_reference<unsigned char, mp11::mp_list_c<int,1,2,3>, rgb_layout_t, true> const; | |
95 | /// | |
96 | /// // create the pixel reference at bit offset 2 | |
97 | /// // (i.e. red = [2], green = [3,4], blue = [5,6,7] bits) | |
98 | /// rgb123_ref_t ref(&data, 2); | |
99 | /// get_color(ref, red_t()) = 1; | |
100 | /// assert(data == 0x04); | |
101 | /// get_color(ref, green_t()) = 3; | |
102 | /// assert(data == 0x1C); | |
103 | /// get_color(ref, blue_t()) = 7; | |
104 | /// assert(data == 0xFC); | |
105 | /// \endcode | |
106 | /// | |
7c673cae FG |
107 | /// \ingroup ColorBaseModelNonAlignedPixel PixelModelNonAlignedPixel PixelBasedModel |
108 | /// \brief Heterogeneous pixel reference corresponding to non-byte-aligned bit range. Models ColorBaseConcept, PixelConcept, PixelBasedConcept | |
92f5a8d4 TL |
109 | /// |
110 | /// \tparam BitField | |
111 | /// \tparam ChannelBitSizes Boost.MP11-compatible list of integral types defining the number of bits for each channel. For example, for 565RGB, mp_list_c<int,5,6,5> | |
112 | /// \tparam Layout | |
113 | /// \tparam IsMutable | |
114 | template <typename BitField, typename ChannelBitSizes, typename Layout, bool IsMutable> | |
115 | struct bit_aligned_pixel_reference | |
116 | { | |
117 | static constexpr int bit_size = | |
118 | mp11::mp_fold | |
119 | < | |
120 | ChannelBitSizes, | |
121 | std::integral_constant<int, 0>, | |
122 | mp11::mp_plus | |
123 | >::value; | |
124 | ||
125 | using bit_range_t = boost::gil::bit_range<bit_size,IsMutable>; | |
126 | using bitfield_t = BitField; | |
127 | using data_ptr_t = mp11::mp_if_c<IsMutable, unsigned char*, const unsigned char*>; | |
128 | ||
129 | using layout_t = Layout; | |
130 | ||
131 | using value_type = typename packed_pixel_type<bitfield_t,ChannelBitSizes,Layout>::type; | |
132 | using reference = const bit_aligned_pixel_reference<BitField, ChannelBitSizes, Layout, IsMutable>; | |
133 | using const_reference = bit_aligned_pixel_reference<BitField,ChannelBitSizes,Layout,false> const; | |
134 | ||
135 | static constexpr bool is_mutable = IsMutable; | |
7c673cae FG |
136 | |
137 | bit_aligned_pixel_reference(){} | |
138 | bit_aligned_pixel_reference(data_ptr_t data_ptr, int bit_offset) : _bit_range(data_ptr, bit_offset) {} | |
139 | explicit bit_aligned_pixel_reference(const bit_range_t& bit_range) : _bit_range(bit_range) {} | |
140 | template <bool IsMutable2> bit_aligned_pixel_reference(const bit_aligned_pixel_reference<BitField,ChannelBitSizes,Layout,IsMutable2>& p) : _bit_range(p._bit_range) {} | |
141 | ||
142 | // Grayscale references can be constructed from the channel reference | |
92f5a8d4 TL |
143 | explicit bit_aligned_pixel_reference(typename kth_element_type<bit_aligned_pixel_reference,0>::type const channel0) |
144 | : _bit_range(static_cast<data_ptr_t>(&channel0), channel0.first_bit()) | |
145 | { | |
146 | static_assert(num_channels<bit_aligned_pixel_reference>::value == 1, ""); | |
7c673cae FG |
147 | } |
148 | ||
149 | // Construct from another compatible pixel type | |
92f5a8d4 TL |
150 | bit_aligned_pixel_reference(bit_aligned_pixel_reference const& p) |
151 | : _bit_range(p._bit_range) {} | |
152 | ||
153 | // TODO: Why p by non-const reference? | |
154 | template <typename BF, typename CR> | |
155 | bit_aligned_pixel_reference(packed_pixel<BF, CR, Layout>& p) | |
156 | : _bit_range(static_cast<data_ptr_t>(&gil::at_c<0>(p)), gil::at_c<0>(p).first_bit()) | |
157 | { | |
158 | check_compatible<packed_pixel<BF, CR, Layout>>(); | |
159 | } | |
160 | ||
161 | auto operator=(bit_aligned_pixel_reference const& p) const | |
162 | -> bit_aligned_pixel_reference const& | |
163 | { | |
164 | static_copy(p, *this); | |
165 | return *this; | |
166 | } | |
167 | ||
168 | template <typename P> | |
169 | auto operator=(P const& p) const -> bit_aligned_pixel_reference const& | |
170 | { | |
171 | assign(p, is_pixel<P>()); | |
172 | return *this; | |
7c673cae FG |
173 | } |
174 | ||
92f5a8d4 TL |
175 | template <typename P> |
176 | bool operator==(P const& p) const | |
177 | { | |
178 | return equal(p, is_pixel<P>()); | |
179 | } | |
180 | ||
181 | template <typename P> | |
182 | bool operator!=(P const& p) const { return !(*this==p); } | |
7c673cae | 183 | |
92f5a8d4 | 184 | auto operator->() const -> bit_aligned_pixel_reference const* { return this; } |
7c673cae | 185 | |
92f5a8d4 | 186 | bit_range_t const& bit_range() const { return _bit_range; } |
7c673cae | 187 | |
7c673cae FG |
188 | private: |
189 | mutable bit_range_t _bit_range; | |
190 | template <typename B, typename C, typename L, bool M> friend struct bit_aligned_pixel_reference; | |
191 | ||
192 | template <typename Pixel> static void check_compatible() { gil_function_requires<PixelsCompatibleConcept<Pixel,bit_aligned_pixel_reference> >(); } | |
193 | ||
92f5a8d4 TL |
194 | template <typename Pixel> |
195 | void assign(Pixel const& p, std::true_type) const | |
196 | { | |
197 | check_compatible<Pixel>(); | |
198 | static_copy(p, *this); | |
199 | } | |
200 | ||
201 | template <typename Pixel> | |
202 | bool equal(Pixel const& p, std::true_type) const | |
203 | { | |
204 | check_compatible<Pixel>(); | |
205 | return static_equal(*this, p); | |
206 | } | |
7c673cae FG |
207 | |
208 | private: | |
92f5a8d4 TL |
209 | static void check_gray() |
210 | { | |
211 | static_assert(std::is_same<typename Layout::color_space_t, gray_t>::value, ""); | |
212 | } | |
213 | ||
214 | template <typename Channel> | |
215 | void assign(Channel const& channel, std::false_type) const | |
216 | { | |
217 | check_gray(); | |
218 | gil::at_c<0>(*this) = channel; | |
219 | } | |
220 | ||
221 | template <typename Channel> | |
222 | bool equal (Channel const& channel, std::false_type) const | |
223 | { | |
224 | check_gray(); | |
225 | return gil::at_c<0>(*this) == channel; | |
226 | } | |
7c673cae FG |
227 | }; |
228 | ||
229 | ///////////////////////////// | |
230 | // ColorBasedConcept | |
231 | ///////////////////////////// | |
232 | ||
92f5a8d4 TL |
233 | template <typename BitField, typename ChannelBitSizes, typename L, bool IsMutable, int K> |
234 | struct kth_element_type | |
235 | < | |
236 | bit_aligned_pixel_reference<BitField, ChannelBitSizes, L, IsMutable>, | |
237 | K | |
238 | > | |
239 | { | |
240 | using type = packed_dynamic_channel_reference | |
241 | < | |
242 | BitField, | |
243 | mp11::mp_at_c<ChannelBitSizes, K>::value, | |
244 | IsMutable | |
245 | > const; | |
7c673cae FG |
246 | }; |
247 | ||
92f5a8d4 | 248 | template <typename B, typename C, typename L, bool M, int K> |
7c673cae FG |
249 | struct kth_element_reference_type<bit_aligned_pixel_reference<B,C,L,M>, K> |
250 | : public kth_element_type<bit_aligned_pixel_reference<B,C,L,M>, K> {}; | |
251 | ||
92f5a8d4 | 252 | template <typename B, typename C, typename L, bool M, int K> |
7c673cae FG |
253 | struct kth_element_const_reference_type<bit_aligned_pixel_reference<B,C,L,M>, K> |
254 | : public kth_element_type<bit_aligned_pixel_reference<B,C,L,M>, K> {}; | |
255 | ||
7c673cae | 256 | namespace detail { |
7c673cae | 257 | |
92f5a8d4 TL |
258 | // returns sum of IntegralVector[0] ... IntegralVector[K-1] |
259 | template <typename IntegralVector, int K> | |
260 | struct sum_k | |
261 | : mp11::mp_plus | |
262 | < | |
263 | sum_k<IntegralVector, K - 1>, | |
264 | typename mp11::mp_at_c<IntegralVector, K - 1>::type | |
265 | > | |
266 | {}; | |
267 | ||
268 | template <typename IntegralVector> | |
269 | struct sum_k<IntegralVector, 0> : std::integral_constant<int, 0> {}; | |
270 | ||
271 | } // namespace detail | |
7c673cae FG |
272 | |
273 | // at_c required by MutableColorBaseConcept | |
92f5a8d4 TL |
274 | template <int K, typename BitField, typename ChannelBitSizes, typename L, bool IsMutable> |
275 | inline | |
276 | auto at_c(const bit_aligned_pixel_reference<BitField, ChannelBitSizes, L, IsMutable>& p) | |
277 | -> typename kth_element_reference_type<bit_aligned_pixel_reference<BitField, ChannelBitSizes, L, IsMutable>, K>::type | |
278 | { | |
279 | using pixel_t = bit_aligned_pixel_reference<BitField, ChannelBitSizes, L, IsMutable>; | |
280 | using channel_t = typename kth_element_reference_type<pixel_t, K>::type; | |
281 | using bit_range_t = typename pixel_t::bit_range_t; | |
7c673cae FG |
282 | |
283 | bit_range_t bit_range(p.bit_range()); | |
92f5a8d4 | 284 | bit_range.bit_advance(detail::sum_k<ChannelBitSizes, K>::value); |
7c673cae | 285 | |
92f5a8d4 | 286 | return channel_t(bit_range.current_byte(), bit_range.bit_offset()); |
7c673cae FG |
287 | } |
288 | ||
289 | ///////////////////////////// | |
290 | // PixelConcept | |
291 | ///////////////////////////// | |
292 | ||
293 | /// Metafunction predicate that flags bit_aligned_pixel_reference as a model of PixelConcept. Required by PixelConcept | |
92f5a8d4 TL |
294 | template <typename B, typename C, typename L, bool M> |
295 | struct is_pixel<bit_aligned_pixel_reference<B, C, L, M> > : std::true_type {}; | |
7c673cae FG |
296 | |
297 | ///////////////////////////// | |
298 | // PixelBasedConcept | |
299 | ///////////////////////////// | |
300 | ||
301 | template <typename B, typename C, typename L, bool M> | |
92f5a8d4 TL |
302 | struct color_space_type<bit_aligned_pixel_reference<B, C, L, M>> |
303 | { | |
304 | using type = typename L::color_space_t; | |
305 | }; | |
7c673cae FG |
306 | |
307 | template <typename B, typename C, typename L, bool M> | |
92f5a8d4 TL |
308 | struct channel_mapping_type<bit_aligned_pixel_reference<B, C, L, M>> |
309 | { | |
310 | using type = typename L::channel_mapping_t; | |
311 | }; | |
7c673cae FG |
312 | |
313 | template <typename B, typename C, typename L, bool M> | |
92f5a8d4 | 314 | struct is_planar<bit_aligned_pixel_reference<B, C, L, M>> : std::false_type {}; |
7c673cae FG |
315 | |
316 | ///////////////////////////// | |
317 | // pixel_reference_type | |
318 | ///////////////////////////// | |
319 | ||
7c673cae | 320 | // Constructs a homogeneous bit_aligned_pixel_reference given a channel reference |
92f5a8d4 TL |
321 | template <typename BitField, int NumBits, typename Layout> |
322 | struct pixel_reference_type | |
323 | < | |
324 | packed_dynamic_channel_reference<BitField, NumBits, false> const, | |
325 | Layout, false, false | |
326 | > | |
327 | { | |
7c673cae | 328 | private: |
92f5a8d4 TL |
329 | using channel_bit_sizes_t = mp11::mp_repeat |
330 | < | |
331 | mp11::mp_list<std::integral_constant<unsigned, NumBits>>, | |
332 | mp11::mp_size<typename Layout::color_space_t> | |
333 | >; | |
334 | ||
7c673cae | 335 | public: |
92f5a8d4 TL |
336 | using type = |
337 | bit_aligned_pixel_reference<BitField, channel_bit_sizes_t, Layout, false>; | |
7c673cae FG |
338 | }; |
339 | ||
92f5a8d4 TL |
340 | // Same but for the mutable case. We cannot combine the mutable |
341 | // and read-only cases because this triggers ambiguity | |
342 | template <typename BitField, int NumBits, typename Layout> | |
343 | struct pixel_reference_type | |
344 | < | |
345 | packed_dynamic_channel_reference<BitField, NumBits, true> const, | |
346 | Layout, false, true | |
347 | > | |
348 | { | |
7c673cae | 349 | private: |
92f5a8d4 TL |
350 | using channel_bit_sizes_t = mp11::mp_repeat |
351 | < | |
352 | mp11::mp_list<std::integral_constant<unsigned, NumBits>>, | |
353 | mp11::mp_size<typename Layout::color_space_t> | |
354 | >; | |
355 | ||
7c673cae | 356 | public: |
92f5a8d4 | 357 | using type = bit_aligned_pixel_reference<BitField, channel_bit_sizes_t, Layout, true>; |
7c673cae FG |
358 | }; |
359 | ||
360 | } } // namespace boost::gil | |
361 | ||
362 | namespace std { | |
92f5a8d4 | 363 | |
7c673cae | 364 | // We are forced to define swap inside std namespace because on some platforms (Visual Studio 8) STL calls swap qualified. |
92f5a8d4 | 365 | // swap with 'left bias': |
7c673cae FG |
366 | // - swap between proxy and anything |
367 | // - swap between value type and proxy | |
368 | // - swap between proxy and proxy | |
369 | // Having three overloads allows us to swap between different (but compatible) models of PixelConcept | |
370 | ||
371 | template <typename B, typename C, typename L, typename R> inline | |
92f5a8d4 TL |
372 | void swap(const boost::gil::bit_aligned_pixel_reference<B,C,L,true> x, R& y) { |
373 | boost::gil::swap_proxy<typename boost::gil::bit_aligned_pixel_reference<B,C,L,true>::value_type>(x,y); | |
7c673cae FG |
374 | } |
375 | ||
376 | ||
377 | template <typename B, typename C, typename L> inline | |
92f5a8d4 TL |
378 | void swap(typename boost::gil::bit_aligned_pixel_reference<B,C,L,true>::value_type& x, const boost::gil::bit_aligned_pixel_reference<B,C,L,true> y) { |
379 | boost::gil::swap_proxy<typename boost::gil::bit_aligned_pixel_reference<B,C,L,true>::value_type>(x,y); | |
7c673cae FG |
380 | } |
381 | ||
382 | ||
383 | template <typename B, typename C, typename L> inline | |
92f5a8d4 TL |
384 | void swap(const boost::gil::bit_aligned_pixel_reference<B,C,L,true> x, const boost::gil::bit_aligned_pixel_reference<B,C,L,true> y) { |
385 | boost::gil::swap_proxy<typename boost::gil::bit_aligned_pixel_reference<B,C,L,true>::value_type>(x,y); | |
7c673cae | 386 | } |
92f5a8d4 TL |
387 | |
388 | } // namespace std | |
389 | ||
7c673cae | 390 | #endif |