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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 libswscale
39  * Color conversion and scaling library.
40  *
41  * @{
42  *
43  * Return the LIBSWSCALE_VERSION_INT constant.
44  */
45 unsigned swscale_version(void);
46 
47 /**
48  * Return the libswscale build-time configuration.
49  */
50 const char *swscale_configuration(void);
51 
52 /**
53  * Return the libswscale license.
54  */
55 const char *swscale_license(void);
56 
57 /* values for the flags, the stuff on the command line is different */
58 #define SWS_FAST_BILINEAR 1
59 #define SWS_BILINEAR 2
60 #define SWS_BICUBIC 4
61 #define SWS_X 8
62 #define SWS_POINT 0x10
63 #define SWS_AREA 0x20
64 #define SWS_BICUBLIN 0x40
65 #define SWS_GAUSS 0x80
66 #define SWS_SINC 0x100
67 #define SWS_LANCZOS 0x200
68 #define SWS_SPLINE 0x400
69 
70 #define SWS_SRC_V_CHR_DROP_MASK 0x30000
71 #define SWS_SRC_V_CHR_DROP_SHIFT 16
72 
73 #define SWS_PARAM_DEFAULT 123456
74 
75 #define SWS_PRINT_INFO 0x1000
76 
77 //the following 3 flags are not completely implemented
78 //internal chrominance subsampling info
79 #define SWS_FULL_CHR_H_INT 0x2000
80 //input subsampling info
81 #define SWS_FULL_CHR_H_INP 0x4000
82 #define SWS_DIRECT_BGR 0x8000
83 #define SWS_ACCURATE_RND 0x40000
84 #define SWS_BITEXACT 0x80000
85 #define SWS_ERROR_DIFFUSION 0x800000
86 
87 #define SWS_MAX_REDUCE_CUTOFF 0.002
88 
89 #define SWS_CS_ITU709 1
90 #define SWS_CS_FCC 4
91 #define SWS_CS_ITU601 5
92 #define SWS_CS_ITU624 5
93 #define SWS_CS_SMPTE170M 5
94 #define SWS_CS_SMPTE240M 7
95 #define SWS_CS_DEFAULT 5
96 #define SWS_CS_BT2020 9
97 
98 /**
99  * Return a pointer to yuv<->rgb coefficients for the given colorspace
100  * suitable for sws_setColorspaceDetails().
101  *
102  * @param colorspace One of the SWS_CS_* macros. If invalid,
103  * SWS_CS_DEFAULT is used.
104  */
105 const int *sws_getCoefficients(int colorspace);
106 
107 // when used for filters they must have an odd number of elements
108 // coeffs cannot be shared between vectors
109 typedef struct SwsVector {
110  double *coeff; ///< pointer to the list of coefficients
111  int length; ///< number of coefficients in the vector
112 } SwsVector;
113 
114 // vectors can be shared
115 typedef struct SwsFilter {
120 } SwsFilter;
121 
122 struct SwsContext;
123 
124 /**
125  * Return a positive value if pix_fmt is a supported input format, 0
126  * otherwise.
127  */
129 
130 /**
131  * Return a positive value if pix_fmt is a supported output format, 0
132  * otherwise.
133  */
135 
136 /**
137  * @param[in] pix_fmt the pixel format
138  * @return a positive value if an endianness conversion for pix_fmt is
139  * supported, 0 otherwise.
140  */
142 
143 /**
144  * Allocate an empty SwsContext. This must be filled and passed to
145  * sws_init_context(). For filling see AVOptions, options.c and
146  * sws_setColorspaceDetails().
147  */
148 struct SwsContext *sws_alloc_context(void);
149 
150 /**
151  * Initialize the swscaler context sws_context.
152  *
153  * @return zero or positive value on success, a negative value on
154  * error
155  */
157 int sws_init_context(struct SwsContext *sws_context, SwsFilter *srcFilter, SwsFilter *dstFilter);
158 
159 /**
160  * Free the swscaler context swsContext.
161  * If swsContext is NULL, then does nothing.
162  */
163 void sws_freeContext(struct SwsContext *swsContext);
164 
165 /**
166  * Allocate and return an SwsContext. You need it to perform
167  * scaling/conversion operations using sws_scale().
168  *
169  * @param srcW the width of the source image
170  * @param srcH the height of the source image
171  * @param srcFormat the source image format
172  * @param dstW the width of the destination image
173  * @param dstH the height of the destination image
174  * @param dstFormat the destination image format
175  * @param flags specify which algorithm and options to use for rescaling
176  * @param param extra parameters to tune the used scaler
177  * For SWS_BICUBIC param[0] and [1] tune the shape of the basis
178  * function, param[0] tunes f(1) and param[1] f´(1)
179  * For SWS_GAUSS param[0] tunes the exponent and thus cutoff
180  * frequency
181  * For SWS_LANCZOS param[0] tunes the width of the window function
182  * @return a pointer to an allocated context, or NULL in case of error
183  * @note this function is to be removed after a saner alternative is
184  * written
185  */
187  int dstW, int dstH, enum AVPixelFormat dstFormat,
188  int flags, SwsFilter *srcFilter,
189  SwsFilter *dstFilter, const double *param);
190 
191 /**
192  * Scale the image slice in srcSlice and put the resulting scaled
193  * slice in the image in dst. A slice is a sequence of consecutive
194  * rows in an image.
195  *
196  * Slices have to be provided in sequential order, either in
197  * top-bottom or bottom-top order. If slices are provided in
198  * non-sequential order the behavior of the function is undefined.
199  *
200  * @param c the scaling context previously created with
201  * sws_getContext()
202  * @param srcSlice the array containing the pointers to the planes of
203  * the source slice
204  * @param srcStride the array containing the strides for each plane of
205  * the source image
206  * @param srcSliceY the position in the source image of the slice to
207  * process, that is the number (counted starting from
208  * zero) in the image of the first row of the slice
209  * @param srcSliceH the height of the source slice, that is the number
210  * of rows in the slice
211  * @param dst the array containing the pointers to the planes of
212  * the destination image
213  * @param dstStride the array containing the strides for each plane of
214  * the destination image
215  * @return the height of the output slice
216  */
217 int sws_scale(struct SwsContext *c, const uint8_t *const srcSlice[],
218  const int srcStride[], int srcSliceY, int srcSliceH,
219  uint8_t *const dst[], const int dstStride[]);
220 
221 /**
222  * @param dstRange flag indicating the while-black range of the output (1=jpeg / 0=mpeg)
223  * @param srcRange flag indicating the while-black range of the input (1=jpeg / 0=mpeg)
224  * @param table the yuv2rgb coefficients describing the output yuv space, normally ff_yuv2rgb_coeffs[x]
225  * @param inv_table the yuv2rgb coefficients describing the input yuv space, normally ff_yuv2rgb_coeffs[x]
226  * @param brightness 16.16 fixed point brightness correction
227  * @param contrast 16.16 fixed point contrast correction
228  * @param saturation 16.16 fixed point saturation correction
229  * @return -1 if not supported
230  */
231 int sws_setColorspaceDetails(struct SwsContext *c, const int inv_table[4],
232  int srcRange, const int table[4], int dstRange,
233  int brightness, int contrast, int saturation);
234 
235 /**
236  * @return -1 if not supported
237  */
238 int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table,
239  int *srcRange, int **table, int *dstRange,
240  int *brightness, int *contrast, int *saturation);
241 
242 /**
243  * Allocate and return an uninitialized vector with length coefficients.
244  */
246 
247 /**
248  * Return a normalized Gaussian curve used to filter stuff
249  * quality = 3 is high quality, lower is lower quality.
250  */
251 SwsVector *sws_getGaussianVec(double variance, double quality);
252 
253 /**
254  * Scale all the coefficients of a by the scalar value.
255  */
256 void sws_scaleVec(SwsVector *a, double scalar);
257 
258 /**
259  * Scale all the coefficients of a so that their sum equals height.
260  */
261 void sws_normalizeVec(SwsVector *a, double height);
262 
263 #if FF_API_SWS_VECTOR
271 attribute_deprecated void sws_printVec2(SwsVector *a, AVClass *log_ctx, int log_level);
272 #endif
273 
274 void sws_freeVec(SwsVector *a);
275 
276 SwsFilter *sws_getDefaultFilter(float lumaGBlur, float chromaGBlur,
277  float lumaSharpen, float chromaSharpen,
278  float chromaHShift, float chromaVShift,
279  int verbose);
281 
282 /**
283  * Check if context can be reused, otherwise reallocate a new one.
284  *
285  * If context is NULL, just calls sws_getContext() to get a new
286  * context. Otherwise, checks if the parameters are the ones already
287  * saved in context. If that is the case, returns the current
288  * context. Otherwise, frees context and gets a new context with
289  * the new parameters.
290  *
291  * Be warned that srcFilter and dstFilter are not checked, they
292  * are assumed to remain the same.
293  */
294 struct SwsContext *sws_getCachedContext(struct SwsContext *context,
295  int srcW, int srcH, enum AVPixelFormat srcFormat,
296  int dstW, int dstH, enum AVPixelFormat dstFormat,
297  int flags, SwsFilter *srcFilter,
298  SwsFilter *dstFilter, const double *param);
299 
300 /**
301  * Convert an 8-bit paletted frame into a frame with a color depth of 32 bits.
302  *
303  * The output frame will have the same packed format as the palette.
304  *
305  * @param src source frame buffer
306  * @param dst destination frame buffer
307  * @param num_pixels number of pixels to convert
308  * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
309  */
310 void sws_convertPalette8ToPacked32(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
311 
312 /**
313  * Convert an 8-bit paletted frame into a frame with a color depth of 24 bits.
314  *
315  * With the palette format "ABCD", the destination frame ends up with the format "ABC".
316  *
317  * @param src source frame buffer
318  * @param dst destination frame buffer
319  * @param num_pixels number of pixels to convert
320  * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
321  */
322 void sws_convertPalette8ToPacked24(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
323 
324 /**
325  * Get the AVClass for swsContext. It can be used in combination with
326  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
327  *
328  * @see av_opt_find().
329  */
330 const AVClass *sws_get_class(void);
331 
332 /**
333  * @}
334  */
335 
336 #endif /* SWSCALE_SWSCALE_H */
SwsVector * chrV
Definition: swscale.h:119
int sws_isSupportedOutput(enum AVPixelFormat pix_fmt)
Return a positive value if pix_fmt is a supported output format, 0 otherwise.
Definition: utils.c:263
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:117
int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table, int *srcRange, int **table, int *dstRange, int *brightness, int *contrast, int *saturation)
Definition: utils.c:987
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:1995
const char * b
Definition: vf_curves.c:113
Convenience header that includes libavutil's core.
int sws_isSupportedEndiannessConversion(enum AVPixelFormat pix_fmt)
Definition: utils.c:269
const char * swscale_configuration(void)
Return the libswscale build-time configuration.
Definition: utils.c:81
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:95
#define src
Definition: vp8dsp.c:254
int srcH
Height of source luma/alpha planes.
attribute_deprecated void sws_convVec(SwsVector *a, SwsVector *b)
Definition: utils.c:2198
uint8_t
int length
number of coefficients in the vector
Definition: swscale.h:111
av_warn_unused_result int sws_init_context(struct SwsContext *sws_context, SwsFilter *srcFilter, SwsFilter *dstFilter)
Initialize the swscaler context sws_context.
Definition: utils.c:1151
attribute_deprecated SwsVector * sws_cloneVec(SwsVector *a)
Definition: utils.c:2211
static void filter(int16_t *output, ptrdiff_t out_stride, int16_t *low, ptrdiff_t low_stride, int16_t *high, ptrdiff_t high_stride, int len, uint8_t clip)
Definition: cfhd.c:80
#define height
attribute_deprecated SwsVector * sws_getConstVec(double c, int length)
Allocate and return a vector with length coefficients, all with the same value c. ...
Definition: utils.c:2028
static int flags
Definition: log.c:57
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:1858
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:1895
static const struct endianess table[]
attribute_deprecated void sws_subVec(SwsVector *a, SwsVector *b)
Definition: utils.c:2185
attribute_deprecated 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:2231
GLsizei GLsizei * length
Definition: opengl_enc.c:115
void sws_scaleVec(SwsVector *a, double scalar)
Scale all the coefficients of a by the scalar value.
Definition: utils.c:2065
SwsVector * lumH
Definition: swscale.h:116
void sws_normalizeVec(SwsVector *a, double height)
Scale all the coefficients of a so that their sum equals height.
Definition: utils.c:2073
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:2338
void sws_freeFilter(SwsFilter *filter)
Definition: utils.c:2266
SwsVector * sws_allocVec(int length)
Allocate and return an uninitialized vector with length coefficients.
Definition: utils.c:1978
int dstRange
0 = MPG YUV range, 1 = JPG YUV range (destination image).
SwsVector * chrH
Definition: swscale.h:118
attribute_deprecated void sws_shiftVec(SwsVector *a, int shift)
Definition: utils.c:2155
void sws_freeContext(struct SwsContext *swsContext)
Free the swscaler context swsContext.
Definition: utils.c:2278
const int * sws_getCoefficients(int colorspace)
Return a pointer to yuv<->rgb coefficients for the given colorspace suitable for sws_setColorspaceDet...
Definition: yuv2rgb.c:63
unsigned swscale_version(void)
Definition: utils.c:75
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:852
int dstW
Width of destination luma/alpha planes.
double * coeff
pointer to the list of coefficients
Definition: swscale.h:110
void sws_freeVec(SwsVector *a)
Definition: utils.c:2257
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:753
Describe the class of an AVClass context structure.
Definition: log.h:67
struct SwsContext * sws_alloc_context(void)
Allocate an empty SwsContext.
Definition: utils.c:1065
#define attribute_deprecated
Definition: attributes.h:94
#define av_warn_unused_result
Definition: attributes.h:56
int palette
Definition: v4l.c:61
attribute_deprecated void sws_addVec(SwsVector *a, SwsVector *b)
Definition: utils.c:2171
double param[2]
Input parameters for scaling algorithms that need them.
enum AVPixelFormat srcFormat
Source pixel format.
pixel format definitions
static AVCodec * c
int sws_isSupportedInput(enum AVPixelFormat pix_fmt)
Return a positive value if pix_fmt is a supported input format, 0 otherwise.
Definition: utils.c:257
attribute_deprecated SwsVector * sws_getIdentityVec(void)
Allocate and return a vector with just one coefficient, with value 1.0.
Definition: utils.c:2049
int srcW
Width of source luma/alpha planes.
AVPixelFormat
Pixel format.
Definition: pixfmt.h:60
const char * swscale_license(void)
Return the libswscale license.
Definition: utils.c:86