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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 #define SWS_MAX_REDUCE_CUTOFF 0.002
86 
87 #define SWS_CS_ITU709 1
88 #define SWS_CS_FCC 4
89 #define SWS_CS_ITU601 5
90 #define SWS_CS_ITU624 5
91 #define SWS_CS_SMPTE170M 5
92 #define SWS_CS_SMPTE240M 7
93 #define SWS_CS_DEFAULT 5
94 
95 /**
96  * Return a pointer to yuv<->rgb coefficients for the given colorspace
97  * suitable for sws_setColorspaceDetails().
98  *
99  * @param colorspace One of the SWS_CS_* macros. If invalid,
100  * SWS_CS_DEFAULT is used.
101  */
102 const int *sws_getCoefficients(int colorspace);
103 
104 // when used for filters they must have an odd number of elements
105 // coeffs cannot be shared between vectors
106 typedef struct SwsVector {
107  double *coeff; ///< pointer to the list of coefficients
108  int length; ///< number of coefficients in the vector
109 } SwsVector;
110 
111 // vectors can be shared
112 typedef struct SwsFilter {
117 } SwsFilter;
118 
119 struct SwsContext;
120 
121 /**
122  * Return a positive value if pix_fmt is a supported input format, 0
123  * otherwise.
124  */
126 
127 /**
128  * Return a positive value if pix_fmt is a supported output format, 0
129  * otherwise.
130  */
132 
133 /**
134  * @param[in] pix_fmt the pixel format
135  * @return a positive value if an endianness conversion for pix_fmt is
136  * supported, 0 otherwise.
137  */
139 
140 /**
141  * Allocate an empty SwsContext. This must be filled and passed to
142  * sws_init_context(). For filling see AVOptions, options.c and
143  * sws_setColorspaceDetails().
144  */
145 struct SwsContext *sws_alloc_context(void);
146 
147 /**
148  * Initialize the swscaler context sws_context.
149  *
150  * @return zero or positive value on success, a negative value on
151  * error
152  */
154 int sws_init_context(struct SwsContext *sws_context, SwsFilter *srcFilter, SwsFilter *dstFilter);
155 
156 /**
157  * Free the swscaler context swsContext.
158  * If swsContext is NULL, then does nothing.
159  */
160 void sws_freeContext(struct SwsContext *swsContext);
161 
162 /**
163  * Allocate and return an SwsContext. You need it to perform
164  * scaling/conversion operations using sws_scale().
165  *
166  * @param srcW the width of the source image
167  * @param srcH the height of the source image
168  * @param srcFormat the source image format
169  * @param dstW the width of the destination image
170  * @param dstH the height of the destination image
171  * @param dstFormat the destination image format
172  * @param flags specify which algorithm and options to use for rescaling
173  * @param param extra parameters to tune the used scaler
174  * For SWS_BICUBIC param[0] and [1] tune the shape of the basis
175  * function, param[0] tunes f(1) and param[1] f´(1)
176  * For SWS_GAUSS param[0] tunes the exponent and thus cutoff
177  * frequency
178  * For SWS_LANCZOS param[0] tunes the width of the window function
179  * @return a pointer to an allocated context, or NULL in case of error
180  * @note this function is to be removed after a saner alternative is
181  * written
182  */
184  int dstW, int dstH, enum AVPixelFormat dstFormat,
185  int flags, SwsFilter *srcFilter,
186  SwsFilter *dstFilter, const double *param);
187 
188 /**
189  * Scale the image slice in srcSlice and put the resulting scaled
190  * slice in the image in dst. A slice is a sequence of consecutive
191  * rows in an image.
192  *
193  * Slices have to be provided in sequential order, either in
194  * top-bottom or bottom-top order. If slices are provided in
195  * non-sequential order the behavior of the function is undefined.
196  *
197  * @param c the scaling context previously created with
198  * sws_getContext()
199  * @param srcSlice the array containing the pointers to the planes of
200  * the source slice
201  * @param srcStride the array containing the strides for each plane of
202  * the source image
203  * @param srcSliceY the position in the source image of the slice to
204  * process, that is the number (counted starting from
205  * zero) in the image of the first row of the slice
206  * @param srcSliceH the height of the source slice, that is the number
207  * of rows in the slice
208  * @param dst the array containing the pointers to the planes of
209  * the destination image
210  * @param dstStride the array containing the strides for each plane of
211  * the destination image
212  * @return the height of the output slice
213  */
214 int sws_scale(struct SwsContext *c, const uint8_t *const srcSlice[],
215  const int srcStride[], int srcSliceY, int srcSliceH,
216  uint8_t *const dst[], const int dstStride[]);
217 
218 /**
219  * @param dstRange flag indicating the while-black range of the output (1=jpeg / 0=mpeg)
220  * @param srcRange flag indicating the while-black range of the input (1=jpeg / 0=mpeg)
221  * @param table the yuv2rgb coefficients describing the output yuv space, normally ff_yuv2rgb_coeffs[x]
222  * @param inv_table the yuv2rgb coefficients describing the input yuv space, normally ff_yuv2rgb_coeffs[x]
223  * @param brightness 16.16 fixed point brightness correction
224  * @param contrast 16.16 fixed point contrast correction
225  * @param saturation 16.16 fixed point saturation correction
226  * @return -1 if not supported
227  */
228 int sws_setColorspaceDetails(struct SwsContext *c, const int inv_table[4],
229  int srcRange, const int table[4], int dstRange,
230  int brightness, int contrast, int saturation);
231 
232 /**
233  * @return -1 if not supported
234  */
235 int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table,
236  int *srcRange, int **table, int *dstRange,
237  int *brightness, int *contrast, int *saturation);
238 
239 /**
240  * Allocate and return an uninitialized vector with length coefficients.
241  */
243 
244 /**
245  * Return a normalized Gaussian curve used to filter stuff
246  * quality = 3 is high quality, lower is lower quality.
247  */
248 SwsVector *sws_getGaussianVec(double variance, double quality);
249 
250 /**
251  * Allocate and return a vector with length coefficients, all
252  * with the same value c.
253  */
254 SwsVector *sws_getConstVec(double c, int length);
255 
256 /**
257  * Allocate and return a vector with just one coefficient, with
258  * value 1.0.
259  */
261 
262 /**
263  * Scale all the coefficients of a by the scalar value.
264  */
265 void sws_scaleVec(SwsVector *a, double scalar);
266 
267 /**
268  * Scale all the coefficients of a so that their sum equals height.
269  */
270 void sws_normalizeVec(SwsVector *a, double height);
272 void sws_addVec(SwsVector *a, SwsVector *b);
273 void sws_subVec(SwsVector *a, SwsVector *b);
274 void sws_shiftVec(SwsVector *a, int shift);
275 
276 /**
277  * Allocate and return a clone of the vector a, that is a vector
278  * with the same coefficients as a.
279  */
281 
282 /**
283  * Print with av_log() a textual representation of the vector a
284  * if log_level <= av_log_level.
285  */
286 void sws_printVec2(SwsVector *a, AVClass *log_ctx, int log_level);
287 
288 void sws_freeVec(SwsVector *a);
289 
290 SwsFilter *sws_getDefaultFilter(float lumaGBlur, float chromaGBlur,
291  float lumaSharpen, float chromaSharpen,
292  float chromaHShift, float chromaVShift,
293  int verbose);
295 
296 /**
297  * Check if context can be reused, otherwise reallocate a new one.
298  *
299  * If context is NULL, just calls sws_getContext() to get a new
300  * context. Otherwise, checks if the parameters are the ones already
301  * saved in context. If that is the case, returns the current
302  * context. Otherwise, frees context and gets a new context with
303  * the new parameters.
304  *
305  * Be warned that srcFilter and dstFilter are not checked, they
306  * are assumed to remain the same.
307  */
308 struct SwsContext *sws_getCachedContext(struct SwsContext *context,
309  int srcW, int srcH, enum AVPixelFormat srcFormat,
310  int dstW, int dstH, enum AVPixelFormat dstFormat,
311  int flags, SwsFilter *srcFilter,
312  SwsFilter *dstFilter, const double *param);
313 
314 /**
315  * Convert an 8-bit paletted frame into a frame with a color depth of 32 bits.
316  *
317  * The output frame will have the same packed format as the palette.
318  *
319  * @param src source frame buffer
320  * @param dst destination frame buffer
321  * @param num_pixels number of pixels to convert
322  * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
323  */
324 void sws_convertPalette8ToPacked32(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
325 
326 /**
327  * Convert an 8-bit paletted frame into a frame with a color depth of 24 bits.
328  *
329  * With the palette format "ABCD", the destination frame ends up with the format "ABC".
330  *
331  * @param src source frame buffer
332  * @param dst destination frame buffer
333  * @param num_pixels number of pixels to convert
334  * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
335  */
336 void sws_convertPalette8ToPacked24(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
337 
338 /**
339  * Get the AVClass for swsContext. It can be used in combination with
340  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
341  *
342  * @see av_opt_find().
343  */
344 const AVClass *sws_get_class(void);
345 
346 /**
347  * @}
348  */
349 
350 #endif /* SWSCALE_SWSCALE_H */
SwsVector * chrV
Definition: swscale.h:116
int sws_isSupportedOutput(enum AVPixelFormat pix_fmt)
Return a positive value if pix_fmt is a supported output format, 0 otherwise.
Definition: utils.c:241
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:114
int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table, int *srcRange, int **table, int *dstRange, int *brightness, int *contrast, int *saturation)
Definition: utils.c:965
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:2017
const char * b
Definition: vf_curves.c:109
external API header
int sws_isSupportedEndiannessConversion(enum AVPixelFormat pix_fmt)
Definition: utils.c:247
const char * swscale_configuration(void)
Return the libswscale build-time configuration.
Definition: utils.c:67
void sws_subVec(SwsVector *a, SwsVector *b)
Definition: utils.c:2182
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
int srcH
Height of source luma/alpha planes.
uint8_t
int length
number of coefficients in the vector
Definition: swscale.h:108
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:1123
void sws_addVec(SwsVector *a, SwsVector *b)
Definition: utils.c:2169
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:82
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:1880
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:1917
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:2220
void sws_scaleVec(SwsVector *a, double scalar)
Scale all the coefficients of a by the scalar value.
Definition: utils.c:2073
SwsVector * lumH
Definition: swscale.h:113
void sws_normalizeVec(SwsVector *a, double height)
Scale all the coefficients of a so that their sum equals height.
Definition: utils.c:2081
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:2346
void sws_freeFilter(SwsFilter *filter)
Definition: utils.c:2255
SwsVector * sws_allocVec(int length)
Allocate and return an uninitialized vector with length coefficients.
Definition: utils.c:2000
int dstRange
0 = MPG YUV range, 1 = JPG YUV range (destination image).
SwsVector * chrH
Definition: swscale.h:115
SwsVector * sws_getIdentityVec(void)
Allocate and return a vector with just one coefficient, with value 1.0.
Definition: utils.c:2057
void sws_freeContext(struct SwsContext *swsContext)
Free the swscaler context swsContext.
Definition: utils.c:2267
const int * sws_getCoefficients(int colorspace)
Return a pointer to yuv<->rgb coefficients for the given colorspace suitable for sws_setColorspaceDet...
Definition: yuv2rgb.c:60
unsigned swscale_version(void)
Definition: utils.c:61
#define src
Definition: vp9dsp.c:530
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:830
int dstW
Width of destination luma/alpha planes.
double * coeff
pointer to the list of coefficients
Definition: swscale.h:107
void sws_freeVec(SwsVector *a)
Definition: utils.c:2246
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:1041
BYTE int const BYTE int int int height
Definition: avisynth_c.h:676
void sws_shiftVec(SwsVector *a, int shift)
Definition: utils.c:2156
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:2208
struct SwsContext * sws_alloc_context(void)
Allocate an empty SwsContext.
Definition: utils.c:1043
static int flags
Definition: cpu.c:47
#define av_warn_unused_result
Definition: attributes.h:56
int palette
Definition: v4l.c:61
void sws_convVec(SwsVector *a, SwsVector *b)
Definition: utils.c:2195
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:235
SwsVector * sws_getConstVec(double c, int length)
Allocate and return a vector with length coefficients, all with the same value c. ...
Definition: utils.c:2043
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:72