FFmpeg
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/frame.h"
34 #include "libavutil/log.h"
35 #include "libavutil/pixfmt.h"
36 #include "version_major.h"
37 #ifndef HAVE_AV_CONFIG_H
38 /* When included as part of the ffmpeg build, only include the major version
39  * to avoid unnecessary rebuilds. When included externally, keep including
40  * the full version information. */
41 #include "version.h"
42 #endif
43 
44 /**
45  * @defgroup libsws libswscale
46  * Color conversion and scaling library.
47  *
48  * @{
49  *
50  * Return the LIBSWSCALE_VERSION_INT constant.
51  */
52 unsigned swscale_version(void);
53 
54 /**
55  * Return the libswscale build-time configuration.
56  */
57 const char *swscale_configuration(void);
58 
59 /**
60  * Return the libswscale license.
61  */
62 const char *swscale_license(void);
63 
64 /* values for the flags, the stuff on the command line is different */
65 #define SWS_FAST_BILINEAR 1
66 #define SWS_BILINEAR 2
67 #define SWS_BICUBIC 4
68 #define SWS_X 8
69 #define SWS_POINT 0x10
70 #define SWS_AREA 0x20
71 #define SWS_BICUBLIN 0x40
72 #define SWS_GAUSS 0x80
73 #define SWS_SINC 0x100
74 #define SWS_LANCZOS 0x200
75 #define SWS_SPLINE 0x400
76 
77 #define SWS_SRC_V_CHR_DROP_MASK 0x30000
78 #define SWS_SRC_V_CHR_DROP_SHIFT 16
79 
80 #define SWS_PARAM_DEFAULT 123456
81 
82 #define SWS_PRINT_INFO 0x1000
83 
84 //the following 3 flags are not completely implemented
85 //internal chrominance subsampling info
86 #define SWS_FULL_CHR_H_INT 0x2000
87 //input subsampling info
88 #define SWS_FULL_CHR_H_INP 0x4000
89 #define SWS_DIRECT_BGR 0x8000
90 #define SWS_ACCURATE_RND 0x40000
91 #define SWS_BITEXACT 0x80000
92 #define SWS_ERROR_DIFFUSION 0x800000
93 
94 #define SWS_MAX_REDUCE_CUTOFF 0.002
95 
96 #define SWS_CS_ITU709 1
97 #define SWS_CS_FCC 4
98 #define SWS_CS_ITU601 5
99 #define SWS_CS_ITU624 5
100 #define SWS_CS_SMPTE170M 5
101 #define SWS_CS_SMPTE240M 7
102 #define SWS_CS_DEFAULT 5
103 #define SWS_CS_BT2020 9
104 
105 /**
106  * Return a pointer to yuv<->rgb coefficients for the given colorspace
107  * suitable for sws_setColorspaceDetails().
108  *
109  * @param colorspace One of the SWS_CS_* macros. If invalid,
110  * SWS_CS_DEFAULT is used.
111  */
112 const int *sws_getCoefficients(int colorspace);
113 
114 // when used for filters they must have an odd number of elements
115 // coeffs cannot be shared between vectors
116 typedef struct SwsVector {
117  double *coeff; ///< pointer to the list of coefficients
118  int length; ///< number of coefficients in the vector
119 } SwsVector;
120 
121 // vectors can be shared
122 typedef struct SwsFilter {
127 } SwsFilter;
128 
129 struct SwsContext;
130 
131 /**
132  * Return a positive value if pix_fmt is a supported input format, 0
133  * otherwise.
134  */
136 
137 /**
138  * Return a positive value if pix_fmt is a supported output format, 0
139  * otherwise.
140  */
142 
143 /**
144  * @param[in] pix_fmt the pixel format
145  * @return a positive value if an endianness conversion for pix_fmt is
146  * supported, 0 otherwise.
147  */
149 
150 /**
151  * Allocate an empty SwsContext. This must be filled and passed to
152  * sws_init_context(). For filling see AVOptions, options.c and
153  * sws_setColorspaceDetails().
154  */
155 struct SwsContext *sws_alloc_context(void);
156 
157 /**
158  * Initialize the swscaler context sws_context.
159  *
160  * @return zero or positive value on success, a negative value on
161  * error
162  */
164 int sws_init_context(struct SwsContext *sws_context, SwsFilter *srcFilter, SwsFilter *dstFilter);
165 
166 /**
167  * Free the swscaler context swsContext.
168  * If swsContext is NULL, then does nothing.
169  */
170 void sws_freeContext(struct SwsContext *swsContext);
171 
172 /**
173  * Allocate and return an SwsContext. You need it to perform
174  * scaling/conversion operations using sws_scale().
175  *
176  * @param srcW the width of the source image
177  * @param srcH the height of the source image
178  * @param srcFormat the source image format
179  * @param dstW the width of the destination image
180  * @param dstH the height of the destination image
181  * @param dstFormat the destination image format
182  * @param flags specify which algorithm and options to use for rescaling
183  * @param param extra parameters to tune the used scaler
184  * For SWS_BICUBIC param[0] and [1] tune the shape of the basis
185  * function, param[0] tunes f(1) and param[1] f´(1)
186  * For SWS_GAUSS param[0] tunes the exponent and thus cutoff
187  * frequency
188  * For SWS_LANCZOS param[0] tunes the width of the window function
189  * @return a pointer to an allocated context, or NULL in case of error
190  * @note this function is to be removed after a saner alternative is
191  * written
192  */
194  int dstW, int dstH, enum AVPixelFormat dstFormat,
195  int flags, SwsFilter *srcFilter,
196  SwsFilter *dstFilter, const double *param);
197 
198 /**
199  * Scale the image slice in srcSlice and put the resulting scaled
200  * slice in the image in dst. A slice is a sequence of consecutive
201  * rows in an image.
202  *
203  * Slices have to be provided in sequential order, either in
204  * top-bottom or bottom-top order. If slices are provided in
205  * non-sequential order the behavior of the function is undefined.
206  *
207  * @param c the scaling context previously created with
208  * sws_getContext()
209  * @param srcSlice the array containing the pointers to the planes of
210  * the source slice
211  * @param srcStride the array containing the strides for each plane of
212  * the source image
213  * @param srcSliceY the position in the source image of the slice to
214  * process, that is the number (counted starting from
215  * zero) in the image of the first row of the slice
216  * @param srcSliceH the height of the source slice, that is the number
217  * of rows in the slice
218  * @param dst the array containing the pointers to the planes of
219  * the destination image
220  * @param dstStride the array containing the strides for each plane of
221  * the destination image
222  * @return the height of the output slice
223  */
224 int sws_scale(struct SwsContext *c, const uint8_t *const srcSlice[],
225  const int srcStride[], int srcSliceY, int srcSliceH,
226  uint8_t *const dst[], const int dstStride[]);
227 
228 /**
229  * Scale source data from src and write the output to dst.
230  *
231  * This is merely a convenience wrapper around
232  * - sws_frame_start()
233  * - sws_send_slice(0, src->height)
234  * - sws_receive_slice(0, dst->height)
235  * - sws_frame_end()
236  *
237  * @param c The scaling context
238  * @param dst The destination frame. See documentation for sws_frame_start() for
239  * more details.
240  * @param src The source frame.
241  *
242  * @return 0 on success, a negative AVERROR code on failure
243  */
244 int sws_scale_frame(struct SwsContext *c, AVFrame *dst, const AVFrame *src);
245 
246 /**
247  * Initialize the scaling process for a given pair of source/destination frames.
248  * Must be called before any calls to sws_send_slice() and sws_receive_slice().
249  *
250  * This function will retain references to src and dst, so they must both use
251  * refcounted buffers (if allocated by the caller, in case of dst).
252  *
253  * @param c The scaling context
254  * @param dst The destination frame.
255  *
256  * The data buffers may either be already allocated by the caller or
257  * left clear, in which case they will be allocated by the scaler.
258  * The latter may have performance advantages - e.g. in certain cases
259  * some output planes may be references to input planes, rather than
260  * copies.
261  *
262  * Output data will be written into this frame in successful
263  * sws_receive_slice() calls.
264  * @param src The source frame. The data buffers must be allocated, but the
265  * frame data does not have to be ready at this point. Data
266  * availability is then signalled by sws_send_slice().
267  * @return 0 on success, a negative AVERROR code on failure
268  *
269  * @see sws_frame_end()
270  */
271 int sws_frame_start(struct SwsContext *c, AVFrame *dst, const AVFrame *src);
272 
273 /**
274  * Finish the scaling process for a pair of source/destination frames previously
275  * submitted with sws_frame_start(). Must be called after all sws_send_slice()
276  * and sws_receive_slice() calls are done, before any new sws_frame_start()
277  * calls.
278  *
279  * @param c The scaling context
280  */
281 void sws_frame_end(struct SwsContext *c);
282 
283 /**
284  * Indicate that a horizontal slice of input data is available in the source
285  * frame previously provided to sws_frame_start(). The slices may be provided in
286  * any order, but may not overlap. For vertically subsampled pixel formats, the
287  * slices must be aligned according to subsampling.
288  *
289  * @param c The scaling context
290  * @param slice_start first row of the slice
291  * @param slice_height number of rows in the slice
292  *
293  * @return a non-negative number on success, a negative AVERROR code on failure.
294  */
295 int sws_send_slice(struct SwsContext *c, unsigned int slice_start,
296  unsigned int slice_height);
297 
298 /**
299  * Request a horizontal slice of the output data to be written into the frame
300  * previously provided to sws_frame_start().
301  *
302  * @param c The scaling context
303  * @param slice_start first row of the slice; must be a multiple of
304  * sws_receive_slice_alignment()
305  * @param slice_height number of rows in the slice; must be a multiple of
306  * sws_receive_slice_alignment(), except for the last slice
307  * (i.e. when slice_start+slice_height is equal to output
308  * frame height)
309  *
310  * @return a non-negative number if the data was successfully written into the output
311  * AVERROR(EAGAIN) if more input data needs to be provided before the
312  * output can be produced
313  * another negative AVERROR code on other kinds of scaling failure
314  */
315 int sws_receive_slice(struct SwsContext *c, unsigned int slice_start,
316  unsigned int slice_height);
317 
318 /**
319  * Get the alignment required for slices
320  *
321  * @param c The scaling context
322  * @return alignment required for output slices requested with sws_receive_slice().
323  * Slice offsets and sizes passed to sws_receive_slice() must be
324  * multiples of the value returned from this function.
325  */
326 unsigned int sws_receive_slice_alignment(const struct SwsContext *c);
327 
328 /**
329  * @param c the scaling context
330  * @param dstRange flag indicating the while-black range of the output (1=jpeg / 0=mpeg)
331  * @param srcRange flag indicating the while-black range of the input (1=jpeg / 0=mpeg)
332  * @param table the yuv2rgb coefficients describing the output yuv space, normally ff_yuv2rgb_coeffs[x]
333  * @param inv_table the yuv2rgb coefficients describing the input yuv space, normally ff_yuv2rgb_coeffs[x]
334  * @param brightness 16.16 fixed point brightness correction
335  * @param contrast 16.16 fixed point contrast correction
336  * @param saturation 16.16 fixed point saturation correction
337  *
338  * @return A negative error code on error, non negative otherwise.
339  * If `LIBSWSCALE_VERSION_MAJOR < 7`, returns -1 if not supported.
340  */
341 int sws_setColorspaceDetails(struct SwsContext *c, const int inv_table[4],
342  int srcRange, const int table[4], int dstRange,
343  int brightness, int contrast, int saturation);
344 
345 /**
346  * @return A negative error code on error, non negative otherwise.
347  * If `LIBSWSCALE_VERSION_MAJOR < 7`, returns -1 if not supported.
348  */
349 int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table,
350  int *srcRange, int **table, int *dstRange,
351  int *brightness, int *contrast, int *saturation);
352 
353 /**
354  * Allocate and return an uninitialized vector with length coefficients.
355  */
356 SwsVector *sws_allocVec(int length);
357 
358 /**
359  * Return a normalized Gaussian curve used to filter stuff
360  * quality = 3 is high quality, lower is lower quality.
361  */
362 SwsVector *sws_getGaussianVec(double variance, double quality);
363 
364 /**
365  * Scale all the coefficients of a by the scalar value.
366  */
367 void sws_scaleVec(SwsVector *a, double scalar);
368 
369 /**
370  * Scale all the coefficients of a so that their sum equals height.
371  */
372 void sws_normalizeVec(SwsVector *a, double height);
373 
374 void sws_freeVec(SwsVector *a);
375 
376 SwsFilter *sws_getDefaultFilter(float lumaGBlur, float chromaGBlur,
377  float lumaSharpen, float chromaSharpen,
378  float chromaHShift, float chromaVShift,
379  int verbose);
381 
382 /**
383  * Check if context can be reused, otherwise reallocate a new one.
384  *
385  * If context is NULL, just calls sws_getContext() to get a new
386  * context. Otherwise, checks if the parameters are the ones already
387  * saved in context. If that is the case, returns the current
388  * context. Otherwise, frees context and gets a new context with
389  * the new parameters.
390  *
391  * Be warned that srcFilter and dstFilter are not checked, they
392  * are assumed to remain the same.
393  */
395  int srcW, int srcH, enum AVPixelFormat srcFormat,
396  int dstW, int dstH, enum AVPixelFormat dstFormat,
397  int flags, SwsFilter *srcFilter,
398  SwsFilter *dstFilter, const double *param);
399 
400 /**
401  * Convert an 8-bit paletted frame into a frame with a color depth of 32 bits.
402  *
403  * The output frame will have the same packed format as the palette.
404  *
405  * @param src source frame buffer
406  * @param dst destination frame buffer
407  * @param num_pixels number of pixels to convert
408  * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
409  */
410 void sws_convertPalette8ToPacked32(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
411 
412 /**
413  * Convert an 8-bit paletted frame into a frame with a color depth of 24 bits.
414  *
415  * With the palette format "ABCD", the destination frame ends up with the format "ABC".
416  *
417  * @param src source frame buffer
418  * @param dst destination frame buffer
419  * @param num_pixels number of pixels to convert
420  * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
421  */
422 void sws_convertPalette8ToPacked24(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
423 
424 /**
425  * Get the AVClass for swsContext. It can be used in combination with
426  * AV_OPT_SEARCH_FAKE_OBJ for examining options.
427  *
428  * @see av_opt_find().
429  */
430 const AVClass *sws_get_class(void);
431 
432 /**
433  * @}
434  */
435 
436 #endif /* SWSCALE_SWSCALE_H */
sws_getCachedContext
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:2500
SwsContext::saturation
int saturation
Definition: swscale_internal.h:454
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:71
version_major.h
SwsContext::dstW
int dstW
Width of destination luma/alpha planes.
Definition: swscale_internal.h:514
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:340
table
static const uint16_t table[]
Definition: prosumer.c:205
SwsContext::srcRange
int srcRange
0 = MPG YUV range, 1 = JPG YUV range (source image).
Definition: swscale_internal.h:457
sws_scale
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:1205
filter
filter_frame For filters that do not use the this method is called when a frame is pushed to the filter s input It can be called at any time except in a reentrant way If the input frame is enough to produce then the filter should push the output frames on the output link immediately As an exception to the previous rule if the input frame is enough to produce several output frames then the filter needs output only at least one per link The additional frames can be left buffered in the filter
Definition: filter_design.txt:228
sws_convertPalette8ToPacked24
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.
Definition: swscale_unscaled.c:2249
sws_send_slice
int sws_send_slice(struct SwsContext *c, unsigned int slice_start, unsigned int slice_height)
Indicate that a horizontal slice of input data is available in the source frame previously provided t...
Definition: swscale.c:1113
quality
trying all byte sequences megabyte in length and selecting the best looking sequence will yield cases to try But a word about quality
Definition: rate_distortion.txt:12
sws_freeVec
void sws_freeVec(SwsVector *a)
Definition: utils.c:2321
sws_receive_slice
int sws_receive_slice(struct SwsContext *c, unsigned int slice_start, unsigned int slice_height)
Request a horizontal slice of the output data to be written into the frame previously provided to sws...
Definition: swscale.c:1133
swscale_license
const char * swscale_license(void)
Return the libswscale license.
Definition: version.c:37
sws_get_class
const AVClass * sws_get_class(void)
Get the AVClass for swsContext.
Definition: options.c:97
slice_start
static int slice_start(SliceContext *sc, VVCContext *s, VVCFrameContext *fc, const CodedBitstreamUnit *unit, const int is_first_slice)
Definition: vvcdec.c:685
SwsContext::srcFormat
enum AVPixelFormat srcFormat
Source pixel format.
Definition: swscale_internal.h:331
sws_frame_start
int sws_frame_start(struct SwsContext *c, AVFrame *dst, const AVFrame *src)
Initialize the scaling process for a given pair of source/destination frames.
Definition: swscale.c:1083
SwsContext::brightness
int brightness
Definition: swscale_internal.h:454
pix_fmt
static enum AVPixelFormat pix_fmt
Definition: demux_decode.c:41
SwsVector::length
int length
number of coefficients in the vector
Definition: swscale.h:118
sws_allocVec
SwsVector * sws_allocVec(int length)
Allocate and return an uninitialized vector with length coefficients.
Definition: utils.c:2131
sws_getGaussianVec
SwsVector * sws_getGaussianVec(double variance, double quality)
Return a normalized Gaussian curve used to filter stuff quality = 3 is high quality,...
Definition: utils.c:2148
SwsContext::contrast
int contrast
Definition: swscale_internal.h:454
SwsContext::dstFormat
enum AVPixelFormat dstFormat
Destination pixel format.
Definition: swscale_internal.h:330
context
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option keep it simple and lowercase description are in without and describe what they for example set the foo of the bar offset is the offset of the field in your context
Definition: writing_filters.txt:91
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:66
sws_getDefaultFilter
SwsFilter * sws_getDefaultFilter(float lumaGBlur, float chromaGBlur, float lumaSharpen, float chromaSharpen, float chromaHShift, float chromaVShift, int verbose)
Definition: utils.c:2342
sws_alloc_context
struct SwsContext * sws_alloc_context(void)
Allocate an empty SwsContext.
Definition: utils.c:1180
SwsVector::coeff
double * coeff
pointer to the list of coefficients
Definition: swscale.h:117
sws_setColorspaceDetails
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:1001
sws_scaleVec
void sws_scaleVec(SwsVector *a, double scalar)
Scale all the coefficients of a by the scalar value.
Definition: utils.c:2214
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
SwsFilter::chrV
SwsVector * chrV
Definition: swscale.h:126
SwsVector
Definition: swscale.h:116
sws_getContext
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:2094
SwsContext::srcH
int srcH
Height of source luma/alpha planes.
Definition: swscale_internal.h:322
srcSliceH
return srcSliceH
Definition: yuv2rgb_template.c:87
frame.h
SwsFilter
Definition: swscale.h:122
height
#define height
a
The reader does not expect b to be semantically here and if the code is changed by maybe adding a a division or other the signedness will almost certainly be mistaken To avoid this confusion a new type was SUINT is the C unsigned type but it holds a signed int to use the same example SUINT a
Definition: undefined.txt:41
SwsFilter::lumV
SwsVector * lumV
Definition: swscale.h:124
swscale_configuration
const char * swscale_configuration(void)
Return the libswscale build-time configuration.
Definition: version.c:32
sws_isSupportedInput
int sws_isSupportedInput(enum AVPixelFormat pix_fmt)
Return a positive value if pix_fmt is a supported input format, 0 otherwise.
Definition: utils.c:329
av_warn_unused_result
#define av_warn_unused_result
Definition: attributes.h:64
sws_scale_frame
int sws_scale_frame(struct SwsContext *c, AVFrame *dst, const AVFrame *src)
Scale source data from src and write the output to dst.
Definition: swscale.c:1184
SwsContext::srcW
int srcW
Width of source luma/alpha planes.
Definition: swscale_internal.h:321
sws_isSupportedEndiannessConversion
int sws_isSupportedEndiannessConversion(enum AVPixelFormat pix_fmt)
Definition: utils.c:341
log.h
SwsContext::dstRange
int dstRange
0 = MPG YUV range, 1 = JPG YUV range (destination image).
Definition: swscale_internal.h:458
sws_receive_slice_alignment
unsigned int sws_receive_slice_alignment(const struct SwsContext *c)
Get the alignment required for slices.
Definition: swscale.c:1125
sws_isSupportedOutput
int sws_isSupportedOutput(enum AVPixelFormat pix_fmt)
Return a positive value if pix_fmt is a supported output format, 0 otherwise.
Definition: utils.c:335
sws_freeFilter
void sws_freeFilter(SwsFilter *filter)
Definition: utils.c:2330
pixfmt.h
verbose
int verbose
Definition: checkasm.c:345
sws_frame_end
void sws_frame_end(struct SwsContext *c)
Finish the scaling process for a pair of source/destination frames previously submitted with sws_fram...
Definition: swscale.c:1076
sws_getColorspaceDetails
int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table, int *srcRange, int **table, int *dstRange, int *brightness, int *contrast, int *saturation)
Definition: utils.c:1156
sws_init_context
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:2036
sws_freeContext
void sws_freeContext(struct SwsContext *swsContext)
Free the swscaler context swsContext.
Definition: utils.c:2425
avutil.h
sws_getCoefficients
const int * sws_getCoefficients(int colorspace)
Return a pointer to yuv<->rgb coefficients for the given colorspace suitable for sws_setColorspaceDet...
Definition: yuv2rgb.c:62
swscale_version
unsigned swscale_version(void)
Definition: version.c:26
SwsFilter::lumH
SwsVector * lumH
Definition: swscale.h:123
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
sws_convertPalette8ToPacked32
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.
Definition: swscale_unscaled.c:2239
SwsContext
Definition: swscale_internal.h:299
SwsFilter::chrH
SwsVector * chrH
Definition: swscale.h:125
SwsContext::dstH
int dstH
Height of destination luma/alpha planes.
Definition: swscale_internal.h:323
sws_normalizeVec
void sws_normalizeVec(SwsVector *a, double height)
Scale all the coefficients of a so that their sum equals height.
Definition: utils.c:2222
SwsContext::param
double param[2]
Input parameters for scaling algorithms that need them.
Definition: swscale_internal.h:342