doxygen: misc consistency, spelling and wording fixes
[libav.git] / libswscale / swscale.h
1 /*
2 * Copyright (C) 2001-2003 Michael Niedermayer <michaelni@gmx.at>
3 *
4 * This file is part of Libav.
5 *
6 * Libav is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * Libav is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with Libav; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #ifndef SWSCALE_SWSCALE_H
22 #define SWSCALE_SWSCALE_H
23
24 /**
25 * @file
26 * @brief
27 * external api for the swscale stuff
28 */
29
30 #include "libavutil/avutil.h"
31 #include "libavutil/log.h"
32 #include "libavutil/pixfmt.h"
33
34 #define LIBSWSCALE_VERSION_MAJOR 2
35 #define LIBSWSCALE_VERSION_MINOR 1
36 #define LIBSWSCALE_VERSION_MICRO 0
37
38 #define LIBSWSCALE_VERSION_INT AV_VERSION_INT(LIBSWSCALE_VERSION_MAJOR, \
39 LIBSWSCALE_VERSION_MINOR, \
40 LIBSWSCALE_VERSION_MICRO)
41 #define LIBSWSCALE_VERSION AV_VERSION(LIBSWSCALE_VERSION_MAJOR, \
42 LIBSWSCALE_VERSION_MINOR, \
43 LIBSWSCALE_VERSION_MICRO)
44 #define LIBSWSCALE_BUILD LIBSWSCALE_VERSION_INT
45
46 #define LIBSWSCALE_IDENT "SwS" AV_STRINGIFY(LIBSWSCALE_VERSION)
47
48 /**
49 * Those FF_API_* defines are not part of public API.
50 * They may change, break or disappear at any time.
51 */
52 #ifndef FF_API_SWS_GETCONTEXT
53 #define FF_API_SWS_GETCONTEXT (LIBSWSCALE_VERSION_MAJOR < 3)
54 #endif
55 #ifndef FF_API_SWS_CPU_CAPS
56 #define FF_API_SWS_CPU_CAPS (LIBSWSCALE_VERSION_MAJOR < 3)
57 #endif
58
59 /**
60 * Return the LIBSWSCALE_VERSION_INT constant.
61 */
62 unsigned swscale_version(void);
63
64 /**
65 * Return the libswscale build-time configuration.
66 */
67 const char *swscale_configuration(void);
68
69 /**
70 * Return the libswscale license.
71 */
72 const char *swscale_license(void);
73
74 /* values for the flags, the stuff on the command line is different */
75 #define SWS_FAST_BILINEAR 1
76 #define SWS_BILINEAR 2
77 #define SWS_BICUBIC 4
78 #define SWS_X 8
79 #define SWS_POINT 0x10
80 #define SWS_AREA 0x20
81 #define SWS_BICUBLIN 0x40
82 #define SWS_GAUSS 0x80
83 #define SWS_SINC 0x100
84 #define SWS_LANCZOS 0x200
85 #define SWS_SPLINE 0x400
86
87 #define SWS_SRC_V_CHR_DROP_MASK 0x30000
88 #define SWS_SRC_V_CHR_DROP_SHIFT 16
89
90 #define SWS_PARAM_DEFAULT 123456
91
92 #define SWS_PRINT_INFO 0x1000
93
94 //the following 3 flags are not completely implemented
95 //internal chrominace subsampling info
96 #define SWS_FULL_CHR_H_INT 0x2000
97 //input subsampling info
98 #define SWS_FULL_CHR_H_INP 0x4000
99 #define SWS_DIRECT_BGR 0x8000
100 #define SWS_ACCURATE_RND 0x40000
101 #define SWS_BITEXACT 0x80000
102
103 #if FF_API_SWS_CPU_CAPS
104 /**
105 * CPU caps are autodetected now, those flags
106 * are only provided for API compatibility.
107 */
108 #define SWS_CPU_CAPS_MMX 0x80000000
109 #define SWS_CPU_CAPS_MMX2 0x20000000
110 #define SWS_CPU_CAPS_3DNOW 0x40000000
111 #define SWS_CPU_CAPS_ALTIVEC 0x10000000
112 #define SWS_CPU_CAPS_BFIN 0x01000000
113 #define SWS_CPU_CAPS_SSE2 0x02000000
114 #endif
115
116 #define SWS_MAX_REDUCE_CUTOFF 0.002
117
118 #define SWS_CS_ITU709 1
119 #define SWS_CS_FCC 4
120 #define SWS_CS_ITU601 5
121 #define SWS_CS_ITU624 5
122 #define SWS_CS_SMPTE170M 5
123 #define SWS_CS_SMPTE240M 7
124 #define SWS_CS_DEFAULT 5
125
126 /**
127 * Return a pointer to yuv<->rgb coefficients for the given colorspace
128 * suitable for sws_setColorspaceDetails().
129 *
130 * @param colorspace One of the SWS_CS_* macros. If invalid,
131 * SWS_CS_DEFAULT is used.
132 */
133 const int *sws_getCoefficients(int colorspace);
134
135
136 // when used for filters they must have an odd number of elements
137 // coeffs cannot be shared between vectors
138 typedef struct {
139 double *coeff; ///< pointer to the list of coefficients
140 int length; ///< number of coefficients in the vector
141 } SwsVector;
142
143 // vectors can be shared
144 typedef struct {
145 SwsVector *lumH;
146 SwsVector *lumV;
147 SwsVector *chrH;
148 SwsVector *chrV;
149 } SwsFilter;
150
151 struct SwsContext;
152
153 /**
154 * Return a positive value if pix_fmt is a supported input format, 0
155 * otherwise.
156 */
157 int sws_isSupportedInput(enum PixelFormat pix_fmt);
158
159 /**
160 * Return a positive value if pix_fmt is a supported output format, 0
161 * otherwise.
162 */
163 int sws_isSupportedOutput(enum PixelFormat pix_fmt);
164
165 /**
166 * Allocate an empty SwsContext. This must be filled and passed to
167 * sws_init_context(). For filling see AVOptions, options.c and
168 * sws_setColorspaceDetails().
169 */
170 struct SwsContext *sws_alloc_context(void);
171
172 /**
173 * Initialize the swscaler context sws_context.
174 *
175 * @return zero or positive value on success, a negative value on
176 * error
177 */
178 int sws_init_context(struct SwsContext *sws_context, SwsFilter *srcFilter, SwsFilter *dstFilter);
179
180 /**
181 * Free the swscaler context swsContext.
182 * If swsContext is NULL, then does nothing.
183 */
184 void sws_freeContext(struct SwsContext *swsContext);
185
186 #if FF_API_SWS_GETCONTEXT
187 /**
188 * Allocate and return an SwsContext. You need it to perform
189 * scaling/conversion operations using sws_scale().
190 *
191 * @param srcW the width of the source image
192 * @param srcH the height of the source image
193 * @param srcFormat the source image format
194 * @param dstW the width of the destination image
195 * @param dstH the height of the destination image
196 * @param dstFormat the destination image format
197 * @param flags specify which algorithm and options to use for rescaling
198 * @return a pointer to an allocated context, or NULL in case of error
199 * @note this function is to be removed after a saner alternative is
200 * written
201 * @deprecated Use sws_getCachedContext() instead.
202 */
203 struct SwsContext *sws_getContext(int srcW, int srcH, enum PixelFormat srcFormat,
204 int dstW, int dstH, enum PixelFormat dstFormat,
205 int flags, SwsFilter *srcFilter,
206 SwsFilter *dstFilter, const double *param);
207 #endif
208
209 /**
210 * Scale the image slice in srcSlice and put the resulting scaled
211 * slice in the image in dst. A slice is a sequence of consecutive
212 * rows in an image.
213 *
214 * Slices have to be provided in sequential order, either in
215 * top-bottom or bottom-top order. If slices are provided in
216 * non-sequential order the behavior of the function is undefined.
217 *
218 * @param c the scaling context previously created with
219 * sws_getContext()
220 * @param srcSlice the array containing the pointers to the planes of
221 * the source slice
222 * @param srcStride the array containing the strides for each plane of
223 * the source image
224 * @param srcSliceY the position in the source image of the slice to
225 * process, that is the number (counted starting from
226 * zero) in the image of the first row of the slice
227 * @param srcSliceH the height of the source slice, that is the number
228 * of rows in the slice
229 * @param dst the array containing the pointers to the planes of
230 * the destination image
231 * @param dstStride the array containing the strides for each plane of
232 * the destination image
233 * @return the height of the output slice
234 */
235 int sws_scale(struct SwsContext *c, const uint8_t* const srcSlice[],
236 const int srcStride[], int srcSliceY, int srcSliceH,
237 uint8_t* const dst[], const int dstStride[]);
238
239 /**
240 * @param inv_table the yuv2rgb coefficients, normally ff_yuv2rgb_coeffs[x]
241 * @return -1 if not supported
242 */
243 int sws_setColorspaceDetails(struct SwsContext *c, const int inv_table[4],
244 int srcRange, const int table[4], int dstRange,
245 int brightness, int contrast, int saturation);
246
247 /**
248 * @return -1 if not supported
249 */
250 int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table,
251 int *srcRange, int **table, int *dstRange,
252 int *brightness, int *contrast, int *saturation);
253
254 /**
255 * Allocate and return an uninitialized vector with length coefficients.
256 */
257 SwsVector *sws_allocVec(int length);
258
259 /**
260 * Return a normalized Gaussian curve used to filter stuff
261 * quality = 3 is high quality, lower is lower quality.
262 */
263 SwsVector *sws_getGaussianVec(double variance, double quality);
264
265 /**
266 * Allocate and return a vector with length coefficients, all
267 * with the same value c.
268 */
269 SwsVector *sws_getConstVec(double c, int length);
270
271 /**
272 * Allocate and return a vector with just one coefficient, with
273 * value 1.0.
274 */
275 SwsVector *sws_getIdentityVec(void);
276
277 /**
278 * Scale all the coefficients of a by the scalar value.
279 */
280 void sws_scaleVec(SwsVector *a, double scalar);
281
282 /**
283 * Scale all the coefficients of a so that their sum equals height.
284 */
285 void sws_normalizeVec(SwsVector *a, double height);
286 void sws_convVec(SwsVector *a, SwsVector *b);
287 void sws_addVec(SwsVector *a, SwsVector *b);
288 void sws_subVec(SwsVector *a, SwsVector *b);
289 void sws_shiftVec(SwsVector *a, int shift);
290
291 /**
292 * Allocate and return a clone of the vector a, that is a vector
293 * with the same coefficients as a.
294 */
295 SwsVector *sws_cloneVec(SwsVector *a);
296
297 /**
298 * Print with av_log() a textual representation of the vector a
299 * if log_level <= av_log_level.
300 */
301 void sws_printVec2(SwsVector *a, AVClass *log_ctx, int log_level);
302
303 void sws_freeVec(SwsVector *a);
304
305 SwsFilter *sws_getDefaultFilter(float lumaGBlur, float chromaGBlur,
306 float lumaSharpen, float chromaSharpen,
307 float chromaHShift, float chromaVShift,
308 int verbose);
309 void sws_freeFilter(SwsFilter *filter);
310
311 /**
312 * Check if context can be reused, otherwise reallocate a new one.
313 *
314 * If context is NULL, just calls sws_getContext() to get a new
315 * context. Otherwise, checks if the parameters are the ones already
316 * saved in context. If that is the case, returns the current
317 * context. Otherwise, frees context and gets a new context with
318 * the new parameters.
319 *
320 * Be warned that srcFilter and dstFilter are not checked, they
321 * are assumed to remain the same.
322 */
323 struct SwsContext *sws_getCachedContext(struct SwsContext *context,
324 int srcW, int srcH, enum PixelFormat srcFormat,
325 int dstW, int dstH, enum PixelFormat dstFormat,
326 int flags, SwsFilter *srcFilter,
327 SwsFilter *dstFilter, const double *param);
328
329 /**
330 * Convert an 8-bit paletted frame into a frame with a color depth of 32 bits.
331 *
332 * The output frame will have the same packed format as the palette.
333 *
334 * @param src source frame buffer
335 * @param dst destination frame buffer
336 * @param num_pixels number of pixels to convert
337 * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
338 */
339 void sws_convertPalette8ToPacked32(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
340
341 /**
342 * Convert an 8-bit paletted frame into a frame with a color depth of 24 bits.
343 *
344 * With the palette format "ABCD", the destination frame ends up with the format "ABC".
345 *
346 * @param src source frame buffer
347 * @param dst destination frame buffer
348 * @param num_pixels number of pixels to convert
349 * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
350 */
351 void sws_convertPalette8ToPacked24(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
352
353 /**
354 * Get the AVClass for swsContext. It can be used in combination with
355 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
356 *
357 * @see av_opt_find().
358 */
359 const AVClass *sws_get_class(void);
360
361 #endif /* SWSCALE_SWSCALE_H */