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swscale.h
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1 /*
2  * Copyright (C) 2001-2011 Michael Niedermayer <michaelni@gmx.at>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg 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  * FFmpeg 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 FFmpeg; 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  * @ingroup libsws
27  * external API header
28  */
29 
30 #include <stdint.h>
31 
32 #include "libavutil/avutil.h"
33 #include "libavutil/log.h"
34 #include "libavutil/pixfmt.h"
35 #include "version.h"
36 
37 /**
38  * @defgroup libsws Color conversion and scaling
39  * @{
40  *
41  * Return the LIBSWSCALE_VERSION_INT constant.
42  */
43 unsigned swscale_version(void);
44 
45 /**
46  * Return the libswscale build-time configuration.
47  */
48 const char *swscale_configuration(void);
49 
50 /**
51  * Return the libswscale license.
52  */
53 const char *swscale_license(void);
54 
55 /* values for the flags, the stuff on the command line is different */
56 #define SWS_FAST_BILINEAR 1
57 #define SWS_BILINEAR 2
58 #define SWS_BICUBIC 4
59 #define SWS_X 8
60 #define SWS_POINT 0x10
61 #define SWS_AREA 0x20
62 #define SWS_BICUBLIN 0x40
63 #define SWS_GAUSS 0x80
64 #define SWS_SINC 0x100
65 #define SWS_LANCZOS 0x200
66 #define SWS_SPLINE 0x400
67 
68 #define SWS_SRC_V_CHR_DROP_MASK 0x30000
69 #define SWS_SRC_V_CHR_DROP_SHIFT 16
70 
71 #define SWS_PARAM_DEFAULT 123456
72 
73 #define SWS_PRINT_INFO 0x1000
74 
75 //the following 3 flags are not completely implemented
76 //internal chrominace subsampling info
77 #define SWS_FULL_CHR_H_INT 0x2000
78 //input subsampling info
79 #define SWS_FULL_CHR_H_INP 0x4000
80 #define SWS_DIRECT_BGR 0x8000
81 #define SWS_ACCURATE_RND 0x40000
82 #define SWS_BITEXACT 0x80000
83 #define SWS_ERROR_DIFFUSION 0x800000
84 
85 #if FF_API_SWS_CPU_CAPS
86 /**
87  * CPU caps are autodetected now, those flags
88  * are only provided for API compatibility.
89  */
90 #define SWS_CPU_CAPS_MMX 0x80000000
91 #define SWS_CPU_CAPS_MMXEXT 0x20000000
92 #define SWS_CPU_CAPS_MMX2 0x20000000
93 #define SWS_CPU_CAPS_3DNOW 0x40000000
94 #define SWS_CPU_CAPS_ALTIVEC 0x10000000
95 #if FF_API_ARCH_BFIN
96 #define SWS_CPU_CAPS_BFIN 0x01000000
97 #endif
98 #define SWS_CPU_CAPS_SSE2 0x02000000
99 #endif
100 
101 #define SWS_MAX_REDUCE_CUTOFF 0.002
102 
103 #define SWS_CS_ITU709 1
104 #define SWS_CS_FCC 4
105 #define SWS_CS_ITU601 5
106 #define SWS_CS_ITU624 5
107 #define SWS_CS_SMPTE170M 5
108 #define SWS_CS_SMPTE240M 7
109 #define SWS_CS_DEFAULT 5
110 
111 /**
112  * Return a pointer to yuv<->rgb coefficients for the given colorspace
113  * suitable for sws_setColorspaceDetails().
114  *
115  * @param colorspace One of the SWS_CS_* macros. If invalid,
116  * SWS_CS_DEFAULT is used.
117  */
118 const int *sws_getCoefficients(int colorspace);
119 
120 // when used for filters they must have an odd number of elements
121 // coeffs cannot be shared between vectors
122 typedef struct SwsVector {
123  double *coeff; ///< pointer to the list of coefficients
124  int length; ///< number of coefficients in the vector
125 } SwsVector;
126 
127 // vectors can be shared
128 typedef struct SwsFilter {
133 } SwsFilter;
134 
135 struct SwsContext;
136 
137 /**
138  * Return a positive value if pix_fmt is a supported input format, 0
139  * otherwise.
140  */
142 
143 /**
144  * Return a positive value if pix_fmt is a supported output format, 0
145  * otherwise.
146  */
148 
149 /**
150  * @param[in] pix_fmt the pixel format
151  * @return a positive value if an endianness conversion for pix_fmt is
152  * supported, 0 otherwise.
153  */
155 
156 /**
157  * Allocate an empty SwsContext. This must be filled and passed to
158  * sws_init_context(). For filling see AVOptions, options.c and
159  * sws_setColorspaceDetails().
160  */
161 struct SwsContext *sws_alloc_context(void);
162 
163 /**
164  * Initialize the swscaler context sws_context.
165  *
166  * @return zero or positive value on success, a negative value on
167  * error
168  */
169 int sws_init_context(struct SwsContext *sws_context, SwsFilter *srcFilter, SwsFilter *dstFilter);
170 
171 /**
172  * Free the swscaler context swsContext.
173  * If swsContext is NULL, then does nothing.
174  */
175 void sws_freeContext(struct SwsContext *swsContext);
176 
177 /**
178  * Allocate and return an SwsContext. You need it to perform
179  * scaling/conversion operations using sws_scale().
180  *
181  * @param srcW the width of the source image
182  * @param srcH the height of the source image
183  * @param srcFormat the source image format
184  * @param dstW the width of the destination image
185  * @param dstH the height of the destination image
186  * @param dstFormat the destination image format
187  * @param flags specify which algorithm and options to use for rescaling
188  * @param param extra parameters to tune the used scaler
189  * For SWS_BICUBIC param[0] and [1] tune the shape of the basis
190  * function, param[0] tunes f(1) and param[1] f´(1)
191  * For SWS_GAUSS param[0] tunes the exponent and thus cutoff
192  * frequency
193  * For SWS_LANCZOS param[0] tunes the width of the window function
194  * @return a pointer to an allocated context, or NULL in case of error
195  * @note this function is to be removed after a saner alternative is
196  * written
197  */
199  int dstW, int dstH, enum AVPixelFormat dstFormat,
200  int flags, SwsFilter *srcFilter,
201  SwsFilter *dstFilter, const double *param);
202 
203 /**
204  * Scale the image slice in srcSlice and put the resulting scaled
205  * slice in the image in dst. A slice is a sequence of consecutive
206  * rows in an image.
207  *
208  * Slices have to be provided in sequential order, either in
209  * top-bottom or bottom-top order. If slices are provided in
210  * non-sequential order the behavior of the function is undefined.
211  *
212  * @param c the scaling context previously created with
213  * sws_getContext()
214  * @param srcSlice the array containing the pointers to the planes of
215  * the source slice
216  * @param srcStride the array containing the strides for each plane of
217  * the source image
218  * @param srcSliceY the position in the source image of the slice to
219  * process, that is the number (counted starting from
220  * zero) in the image of the first row of the slice
221  * @param srcSliceH the height of the source slice, that is the number
222  * of rows in the slice
223  * @param dst the array containing the pointers to the planes of
224  * the destination image
225  * @param dstStride the array containing the strides for each plane of
226  * the destination image
227  * @return the height of the output slice
228  */
229 int sws_scale(struct SwsContext *c, const uint8_t *const srcSlice[],
230  const int srcStride[], int srcSliceY, int srcSliceH,
231  uint8_t *const dst[], const int dstStride[]);
232 
233 /**
234  * @param dstRange flag indicating the while-black range of the output (1=jpeg / 0=mpeg)
235  * @param srcRange flag indicating the while-black range of the input (1=jpeg / 0=mpeg)
236  * @param table the yuv2rgb coefficients describing the output yuv space, normally ff_yuv2rgb_coeffs[x]
237  * @param inv_table the yuv2rgb coefficients describing the input yuv space, normally ff_yuv2rgb_coeffs[x]
238  * @param brightness 16.16 fixed point brightness correction
239  * @param contrast 16.16 fixed point contrast correction
240  * @param saturation 16.16 fixed point saturation correction
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  */
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  */
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);
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  */
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);
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 AVPixelFormat srcFormat,
325  int dstW, int dstH, enum AVPixelFormat 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 /**
362  * @}
363  */
364 
365 #endif /* SWSCALE_SWSCALE_H */
SwsVector * chrV
Definition: swscale.h:132
int sws_isSupportedOutput(enum AVPixelFormat pix_fmt)
Return a positive value if pix_fmt is a supported output format, 0 otherwise.
Definition: utils.c:237
static enum AVPixelFormat pix_fmt
static int shift(int a, int b)
Definition: sonic.c:82
void sws_convertPalette8ToPacked32(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette)
Convert an 8-bit paletted frame into a frame with a color depth of 32 bits.
void sws_convertPalette8ToPacked24(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette)
Convert an 8-bit paletted frame into a frame with a color depth of 24 bits.
SwsVector * lumV
Definition: swscale.h:130
int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table, int *srcRange, int **table, int *dstRange, int *brightness, int *contrast, int *saturation)
Definition: utils.c:947
SwsVector * sws_getGaussianVec(double variance, double quality)
Return a normalized Gaussian curve used to filter stuff quality = 3 is high quality, lower is lower quality.
Definition: utils.c:1975
const char * b
Definition: vf_curves.c:109
external API header
int sws_isSupportedEndiannessConversion(enum AVPixelFormat pix_fmt)
Definition: utils.c:243
const char * swscale_configuration(void)
Return the libswscale build-time configuration.
Definition: utils.c:65
void sws_subVec(SwsVector *a, SwsVector *b)
Definition: utils.c:2140
int srcRange
0 = MPG YUV range, 1 = JPG YUV range (source image).
swscale version macros
const AVClass * sws_get_class(void)
Get the AVClass for swsContext.
Definition: options.c:97
int srcH
Height of source luma/alpha planes.
uint8_t
int length
number of coefficients in the vector
Definition: swscale.h:124
void sws_addVec(SwsVector *a, SwsVector *b)
Definition: utils.c:2127
struct SwsContext * sws_getContext(int srcW, int srcH, enum AVPixelFormat srcFormat, int dstW, int dstH, enum AVPixelFormat dstFormat, int flags, SwsFilter *srcFilter, SwsFilter *dstFilter, const double *param)
Allocate and return an SwsContext.
Definition: utils.c:1838
int sws_init_context(struct SwsContext *sws_context, SwsFilter *srcFilter, SwsFilter *dstFilter)
Initialize the swscaler context sws_context.
Definition: utils.c:1102
enum AVPixelFormat dstFormat
Destination pixel format.
int dstH
Height of destination luma/alpha planes.
SwsFilter * sws_getDefaultFilter(float lumaGBlur, float chromaGBlur, float lumaSharpen, float chromaSharpen, float chromaHShift, float chromaVShift, int verbose)
Definition: utils.c:1875
static const struct endianess table[]
GLsizei GLsizei * length
Definition: opengl_enc.c:115
void sws_printVec2(SwsVector *a, AVClass *log_ctx, int log_level)
Print with av_log() a textual representation of the vector a if log_level <= av_log_level.
Definition: utils.c:2178
void sws_scaleVec(SwsVector *a, double scalar)
Scale all the coefficients of a by the scalar value.
Definition: utils.c:2031
SwsVector * lumH
Definition: swscale.h:129
void sws_normalizeVec(SwsVector *a, double height)
Scale all the coefficients of a so that their sum equals height.
Definition: utils.c:2039
struct SwsContext * sws_getCachedContext(struct SwsContext *context, int srcW, int srcH, enum AVPixelFormat srcFormat, int dstW, int dstH, enum AVPixelFormat dstFormat, int flags, SwsFilter *srcFilter, SwsFilter *dstFilter, const double *param)
Check if context can be reused, otherwise reallocate a new one.
Definition: utils.c:2304
void sws_freeFilter(SwsFilter *filter)
Definition: utils.c:2213
SwsVector * sws_allocVec(int length)
Allocate and return an uninitialized vector with length coefficients.
Definition: utils.c:1958
int dstRange
0 = MPG YUV range, 1 = JPG YUV range (destination image).
SwsVector * chrH
Definition: swscale.h:131
SwsVector * sws_getIdentityVec(void)
Allocate and return a vector with just one coefficient, with value 1.0.
Definition: utils.c:2015
void sws_freeContext(struct SwsContext *swsContext)
Free the swscaler context swsContext.
Definition: utils.c:2225
const int * sws_getCoefficients(int colorspace)
Return a pointer to yuv<->rgb coefficients for the given colorspace suitable for sws_setColorspaceDet...
Definition: yuv2rgb.c:49
unsigned swscale_version(void)
Definition: utils.c:59
int sws_setColorspaceDetails(struct SwsContext *c, const int inv_table[4], int srcRange, const int table[4], int dstRange, int brightness, int contrast, int saturation)
Definition: utils.c:826
int dstW
Width of destination luma/alpha planes.
double * coeff
pointer to the list of coefficients
Definition: swscale.h:123
AVS_Value src
Definition: avisynth_c.h:482
void sws_freeVec(SwsVector *a)
Definition: utils.c:2204
int sws_scale(struct SwsContext *c, const uint8_t *const srcSlice[], const int srcStride[], int srcSliceY, int srcSliceH, uint8_t *const dst[], const int dstStride[])
Scale the image slice in srcSlice and put the resulting scaled slice in the image in dst...
Definition: swscale.c:1036
BYTE int const BYTE int int int height
Definition: avisynth_c.h:676
void sws_shiftVec(SwsVector *a, int shift)
Definition: utils.c:2114
Describe the class of an AVClass context structure.
Definition: log.h:67
SwsVector * sws_cloneVec(SwsVector *a)
Allocate and return a clone of the vector a, that is a vector with the same coefficients as a...
Definition: utils.c:2166
struct SwsContext * sws_alloc_context(void)
Allocate an empty SwsContext.
Definition: utils.c:1022
static int flags
Definition: cpu.c:47
int palette
Definition: v4l.c:61
void sws_convVec(SwsVector *a, SwsVector *b)
Definition: utils.c:2153
static void filter(MpegAudioContext *s, int ch, const short *samples, int incr)
double param[2]
Input parameters for scaling algorithms that need them.
static double c[64]
enum AVPixelFormat srcFormat
Source pixel format.
pixel format definitions
int sws_isSupportedInput(enum AVPixelFormat pix_fmt)
Return a positive value if pix_fmt is a supported input format, 0 otherwise.
Definition: utils.c:231
SwsVector * sws_getConstVec(double c, int length)
Allocate and return a vector with length coefficients, all with the same value c. ...
Definition: utils.c:2001
enum AVColorSpace colorspace
Definition: dirac.c:102
int srcW
Width of source luma/alpha planes.
AVPixelFormat
Pixel format.
Definition: pixfmt.h:61
const char * swscale_license(void)
Return the libswscale license.
Definition: utils.c:70