1/*
2 * Copyright (C) 2024 Niklas Haas
3 * Copyright (C) 2001-2011 Michael Niedermayer <michaelni@gmx.at>
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22#ifndef SWSCALE_SWSCALE_H
23#define SWSCALE_SWSCALE_H
24
25/**
26 * @file
27 * @ingroup libsws
28 * external API header
29 */
30
31#include <stdint.h>
32
33#include "libavutil/avutil.h"
34#include "libavutil/frame.h"
35#include "libavutil/log.h"
36#include "libavutil/pixfmt.h"
37#include "version_major.h"
38#ifndef HAVE_AV_CONFIG_H
39/* When included as part of the ffmpeg build, only include the major version
40 * to avoid unnecessary rebuilds. When included externally, keep including
41 * the full version information. */
42#include "version.h"
43#endif
44
45/**
46 * @defgroup libsws libswscale
47 * Color conversion and scaling library.
48 *
49 * @{
50 *
51 * Return the LIBSWSCALE_VERSION_INT constant.
52 */
53unsigned swscale_version(void);
54
55/**
56 * Return the libswscale build-time configuration.
57 */
58const char *swscale_configuration(void);
59
60/**
61 * Return the libswscale license.
62 */
63const char *swscale_license(void);
64
65/**
66 * Get the AVClass for SwsContext. It can be used in combination with
67 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
68 *
69 * @see av_opt_find().
70 */
71const AVClass *sws_get_class(void);
72
73/******************************
74 * Flags and quality settings *
75 ******************************/
76
77typedef enum SwsDither {
78 SWS_DITHER_NONE = 0, /* disable dithering */
79 SWS_DITHER_AUTO, /* auto-select from preset */
80 SWS_DITHER_BAYER, /* ordered dither matrix */
81 SWS_DITHER_ED, /* error diffusion */
82 SWS_DITHER_A_DITHER, /* arithmetic addition */
83 SWS_DITHER_X_DITHER, /* arithmetic xor */
84 SWS_DITHER_NB, /* not part of the ABI */
85} SwsDither;
86
87typedef enum SwsAlphaBlend {
88 SWS_ALPHA_BLEND_NONE = 0,
89 SWS_ALPHA_BLEND_UNIFORM,
90 SWS_ALPHA_BLEND_CHECKERBOARD,
91 SWS_ALPHA_BLEND_NB, /* not part of the ABI */
92} SwsAlphaBlend;
93
94typedef enum SwsFlags {
95 /**
96 * Scaler selection options. Only one may be active at a time.
97 */
98 SWS_FAST_BILINEAR = 1 << 0, ///< fast bilinear filtering
99 SWS_BILINEAR = 1 << 1, ///< bilinear filtering
100 SWS_BICUBIC = 1 << 2, ///< 2-tap cubic B-spline
101 SWS_X = 1 << 3, ///< experimental
102 SWS_POINT = 1 << 4, ///< nearest neighbor
103 SWS_AREA = 1 << 5, ///< area averaging
104 SWS_BICUBLIN = 1 << 6, ///< bicubic luma, bilinear chroma
105 SWS_GAUSS = 1 << 7, ///< gaussian approximation
106 SWS_SINC = 1 << 8, ///< unwindowed sinc
107 SWS_LANCZOS = 1 << 9, ///< 3-tap sinc/sinc
108 SWS_SPLINE = 1 << 10, ///< cubic Keys spline
109
110 /**
111 * Return an error on underspecified conversions. Without this flag,
112 * unspecified fields are defaulted to sensible values.
113 */
114 SWS_STRICT = 1 << 11,
115
116 /**
117 * Emit verbose log of scaling parameters.
118 */
119 SWS_PRINT_INFO = 1 << 12,
120
121 /**
122 * Perform full chroma upsampling when upscaling to RGB.
123 *
124 * For example, when converting 50x50 yuv420p to 100x100 rgba, setting this flag
125 * will scale the chroma plane from 25x25 to 100x100 (4:4:4), and then convert
126 * the 100x100 yuv444p image to rgba in the final output step.
127 *
128 * Without this flag, the chroma plane is instead scaled to 50x100 (4:2:2),
129 * with a single chroma sample being reused for both of the horizontally
130 * adjacent RGBA output pixels.
131 */
132 SWS_FULL_CHR_H_INT = 1 << 13,
133
134 /**
135 * Perform full chroma interpolation when downscaling RGB sources.
136 *
137 * For example, when converting a 100x100 rgba source to 50x50 yuv444p, setting
138 * this flag will generate a 100x100 (4:4:4) chroma plane, which is then
139 * downscaled to the required 50x50.
140 *
141 * Without this flag, the chroma plane is instead generated at 50x100 (dropping
142 * every other pixel), before then being downscaled to the required 50x50
143 * resolution.
144 */
145 SWS_FULL_CHR_H_INP = 1 << 14,
146
147 /**
148 * Force bit-exact output. This will prevent the use of platform-specific
149 * optimizations that may lead to slight difference in rounding, in favor
150 * of always maintaining exact bit output compatibility with the reference
151 * C code.
152 *
153 * Note: It is recommended to set both of these flags simultaneously.
154 */
155 SWS_ACCURATE_RND = 1 << 18,
156 SWS_BITEXACT = 1 << 19,
157
158 /**
159 * Deprecated flags.
160 */
161 SWS_DIRECT_BGR = 1 << 15, ///< This flag has no effect
162 SWS_ERROR_DIFFUSION = 1 << 23, ///< Set `SwsContext.dither` instead
163} SwsFlags;
164
165typedef enum SwsIntent {
166 SWS_INTENT_PERCEPTUAL = 0, ///< Perceptual tone mapping
167 SWS_INTENT_RELATIVE_COLORIMETRIC = 1, ///< Relative colorimetric clipping
168 SWS_INTENT_SATURATION = 2, ///< Saturation mapping
169 SWS_INTENT_ABSOLUTE_COLORIMETRIC = 3, ///< Absolute colorimetric clipping
170 SWS_INTENT_NB, ///< not part of the ABI
171} SwsIntent;
172
173/***********************************
174 * Context creation and management *
175 ***********************************/
176
177/**
178 * Main external API structure. New fields can be added to the end with
179 * minor version bumps. Removal, reordering and changes to existing fields
180 * require a major version bump. sizeof(SwsContext) is not part of the ABI.
181 */
182typedef struct SwsContext {
183 const AVClass *av_class;
184
185 /**
186 * Private data of the user, can be used to carry app specific stuff.
187 */
188 void *opaque;
189
190 /**
191 * Bitmask of SWS_*. See `SwsFlags` for details.
192 */
193 unsigned flags;
194
195 /**
196 * Extra parameters for fine-tuning certain scalers.
197 */
198 double scaler_params[2];
199
200 /**
201 * How many threads to use for processing, or 0 for automatic selection.
202 */
203 int threads;
204
205 /**
206 * Dither mode.
207 */
208 SwsDither dither;
209
210 /**
211 * Alpha blending mode. See `SwsAlphaBlend` for details.
212 */
213 SwsAlphaBlend alpha_blend;
214
215 /**
216 * Use gamma correct scaling.
217 */
218 int gamma_flag;
219
220 /**
221 * Deprecated frame property overrides, for the legacy API only.
222 *
223 * Ignored by sws_scale_frame() when used in dynamic mode, in which
224 * case all properties are instead taken from the frame directly.
225 */
226 int src_w, src_h; ///< Width and height of the source frame
227 int dst_w, dst_h; ///< Width and height of the destination frame
228 int src_format; ///< Source pixel format
229 int dst_format; ///< Destination pixel format
230 int src_range; ///< Source is full range
231 int dst_range; ///< Destination is full range
232 int src_v_chr_pos; ///< Source vertical chroma position in luma grid / 256
233 int src_h_chr_pos; ///< Source horizontal chroma position
234 int dst_v_chr_pos; ///< Destination vertical chroma position
235 int dst_h_chr_pos; ///< Destination horizontal chroma position
236
237 /**
238 * Desired ICC intent for color space conversions.
239 */
240 int intent;
241
242 /* Remember to add new fields to graph.c:opts_equal() */
243} SwsContext;
244
245/**
246 * Allocate an empty SwsContext and set its fields to default values.
247 */
248SwsContext *sws_alloc_context(void);
249
250/**
251 * Free the context and everything associated with it, and write NULL
252 * to the provided pointer.
253 */
254void sws_free_context(SwsContext **ctx);
255
256/***************************
257 * Supported frame formats *
258 ***************************/
259
260/**
261 * Test if a given pixel format is supported.
262 *
263 * @param output If 0, test if compatible with the source/input frame;
264 * otherwise, with the destination/output frame.
265 * @param format The format to check.
266 *
267 * @return A positive integer if supported, 0 otherwise.
268 */
269int sws_test_format(enum AVPixelFormat format, int output);
270
271/**
272 * Test if a given color space is supported.
273 *
274 * @param output If 0, test if compatible with the source/input frame;
275 * otherwise, with the destination/output frame.
276 * @param colorspace The colorspace to check.
277 *
278 * @return A positive integer if supported, 0 otherwise.
279 */
280int sws_test_colorspace(enum AVColorSpace colorspace, int output);
281
282/**
283 * Test if a given set of color primaries is supported.
284 *
285 * @param output If 0, test if compatible with the source/input frame;
286 * otherwise, with the destination/output frame.
287 * @param primaries The color primaries to check.
288 *
289 * @return A positive integer if supported, 0 otherwise.
290 */
291int sws_test_primaries(enum AVColorPrimaries primaries, int output);
292
293/**
294 * Test if a given color transfer function is supported.
295 *
296 * @param output If 0, test if compatible with the source/input frame;
297 * otherwise, with the destination/output frame.
298 * @param trc The color transfer function to check.
299 *
300 * @return A positive integer if supported, 0 otherwise.
301 */
302int sws_test_transfer(enum AVColorTransferCharacteristic trc, int output);
303
304/**
305 * Helper function to run all sws_test_* against a frame, as well as testing
306 * the basic frame properties for sanity. Ignores irrelevant properties - for
307 * example, AVColorSpace is not checked for RGB frames.
308 */
309int sws_test_frame(const AVFrame *frame, int output);
310
311/**
312 * Like `sws_scale_frame`, but without actually scaling. It will instead
313 * merely initialize internal state that *would* be required to perform the
314 * operation, as well as returning the correct error code for unsupported
315 * frame combinations.
316 *
317 * @param ctx The scaling context.
318 * @param dst The destination frame to consider.
319 * @param src The source frame to consider.
320 * @return 0 on success, a negative AVERROR code on failure.
321 */
322int sws_frame_setup(SwsContext *ctx, const AVFrame *dst, const AVFrame *src);
323
324/********************
325 * Main scaling API *
326 ********************/
327
328/**
329 * Check if a given conversion is a noop. Returns a positive integer if
330 * no operation needs to be performed, 0 otherwise.
331 */
332int sws_is_noop(const AVFrame *dst, const AVFrame *src);
333
334/**
335 * Scale source data from `src` and write the output to `dst`.
336 *
337 * This function can be used directly on an allocated context, without setting
338 * up any frame properties or calling `sws_init_context()`. Such usage is fully
339 * dynamic and does not require reallocation if the frame properties change.
340 *
341 * Alternatively, this function can be called on a context that has been
342 * explicitly initialized. However, this is provided only for backwards
343 * compatibility. In this usage mode, all frame properties must be correctly
344 * set at init time, and may no longer change after initialization.
345 *
346 * @param ctx The scaling context.
347 * @param dst The destination frame. The data buffers may either be already
348 * allocated by the caller or left clear, in which case they will
349 * be allocated by the scaler. The latter may have performance
350 * advantages - e.g. in certain cases some (or all) output planes
351 * may be references to input planes, rather than copies.
352 * @param src The source frame. If the data buffers are set to NULL, then
353 * this function behaves identically to `sws_frame_setup`.
354 * @return >= 0 on success, a negative AVERROR code on failure.
355 */
356int sws_scale_frame(SwsContext *c, AVFrame *dst, const AVFrame *src);
357
358/*************************
359 * Legacy (stateful) API *
360 *************************/
361
362#define SWS_SRC_V_CHR_DROP_MASK 0x30000
363#define SWS_SRC_V_CHR_DROP_SHIFT 16
364
365#define SWS_PARAM_DEFAULT 123456
366
367#define SWS_MAX_REDUCE_CUTOFF 0.002
368
369#define SWS_CS_ITU709 1
370#define SWS_CS_FCC 4
371#define SWS_CS_ITU601 5
372#define SWS_CS_ITU624 5
373#define SWS_CS_SMPTE170M 5
374#define SWS_CS_SMPTE240M 7
375#define SWS_CS_DEFAULT 5
376#define SWS_CS_BT2020 9
377
378/**
379 * Return a pointer to yuv<->rgb coefficients for the given colorspace
380 * suitable for sws_setColorspaceDetails().
381 *
382 * @param colorspace One of the SWS_CS_* macros. If invalid,
383 * SWS_CS_DEFAULT is used.
384 */
385const int *sws_getCoefficients(int colorspace);
386
387// when used for filters they must have an odd number of elements
388// coeffs cannot be shared between vectors
389typedef struct SwsVector {
390 double *coeff; ///< pointer to the list of coefficients
391 int length; ///< number of coefficients in the vector
392} SwsVector;
393
394// vectors can be shared
395typedef struct SwsFilter {
396 SwsVector *lumH;
397 SwsVector *lumV;
398 SwsVector *chrH;
399 SwsVector *chrV;
400} SwsFilter;
401
402/**
403 * Return a positive value if pix_fmt is a supported input format, 0
404 * otherwise.
405 */
406int sws_isSupportedInput(enum AVPixelFormat pix_fmt);
407
408/**
409 * Return a positive value if pix_fmt is a supported output format, 0
410 * otherwise.
411 */
412int sws_isSupportedOutput(enum AVPixelFormat pix_fmt);
413
414/**
415 * @param[in] pix_fmt the pixel format
416 * @return a positive value if an endianness conversion for pix_fmt is
417 * supported, 0 otherwise.
418 */
419int sws_isSupportedEndiannessConversion(enum AVPixelFormat pix_fmt);
420
421/**
422 * Initialize the swscaler context sws_context.
423 *
424 * This function is considered deprecated, and provided only for backwards
425 * compatibility with sws_scale() and sws_start_frame(). The preferred way to
426 * use libswscale is to set all frame properties correctly and call
427 * sws_scale_frame() directly, without explicitly initializing the context.
428 *
429 * @return zero or positive value on success, a negative value on
430 * error
431 */
432av_warn_unused_result
433int sws_init_context(SwsContext *sws_context, SwsFilter *srcFilter, SwsFilter *dstFilter);
434
435/**
436 * Free the swscaler context swsContext.
437 * If swsContext is NULL, then does nothing.
438 */
439void sws_freeContext(SwsContext *swsContext);
440
441/**
442 * Allocate and return an SwsContext. You need it to perform
443 * scaling/conversion operations using sws_scale().
444 *
445 * @param srcW the width of the source image
446 * @param srcH the height of the source image
447 * @param srcFormat the source image format
448 * @param dstW the width of the destination image
449 * @param dstH the height of the destination image
450 * @param dstFormat the destination image format
451 * @param flags specify which algorithm and options to use for rescaling
452 * @param param extra parameters to tune the used scaler
453 * For SWS_BICUBIC param[0] and [1] tune the shape of the basis
454 * function, param[0] tunes f(1) and param[1] f´(1)
455 * For SWS_GAUSS param[0] tunes the exponent and thus cutoff
456 * frequency
457 * For SWS_LANCZOS param[0] tunes the width of the window function
458 * @return a pointer to an allocated context, or NULL in case of error
459 * @note this function is to be removed after a saner alternative is
460 * written
461 */
462SwsContext *sws_getContext(int srcW, int srcH, enum AVPixelFormat srcFormat,
463 int dstW, int dstH, enum AVPixelFormat dstFormat,
464 int flags, SwsFilter *srcFilter,
465 SwsFilter *dstFilter, const double *param);
466
467/**
468 * Scale the image slice in srcSlice and put the resulting scaled
469 * slice in the image in dst. A slice is a sequence of consecutive
470 * rows in an image. Requires a context that has been previously
471 * been initialized with sws_init_context().
472 *
473 * Slices have to be provided in sequential order, either in
474 * top-bottom or bottom-top order. If slices are provided in
475 * non-sequential order the behavior of the function is undefined.
476 *
477 * @param c the scaling context previously created with
478 * sws_getContext()
479 * @param srcSlice the array containing the pointers to the planes of
480 * the source slice
481 * @param srcStride the array containing the strides for each plane of
482 * the source image
483 * @param srcSliceY the position in the source image of the slice to
484 * process, that is the number (counted starting from
485 * zero) in the image of the first row of the slice
486 * @param srcSliceH the height of the source slice, that is the number
487 * of rows in the slice
488 * @param dst the array containing the pointers to the planes of
489 * the destination image
490 * @param dstStride the array containing the strides for each plane of
491 * the destination image
492 * @return the height of the output slice
493 */
494int sws_scale(SwsContext *c, const uint8_t *const srcSlice[],
495 const int srcStride[], int srcSliceY, int srcSliceH,
496 uint8_t *const dst[], const int dstStride[]);
497
498/**
499 * Initialize the scaling process for a given pair of source/destination frames.
500 * Must be called before any calls to sws_send_slice() and sws_receive_slice().
501 * Requires a context that has been previously been initialized with
502 * sws_init_context().
503 *
504 * This function will retain references to src and dst, so they must both use
505 * refcounted buffers (if allocated by the caller, in case of dst).
506 *
507 * @param c The scaling context
508 * @param dst The destination frame.
509 *
510 * The data buffers may either be already allocated by the caller or
511 * left clear, in which case they will be allocated by the scaler.
512 * The latter may have performance advantages - e.g. in certain cases
513 * some output planes may be references to input planes, rather than
514 * copies.
515 *
516 * Output data will be written into this frame in successful
517 * sws_receive_slice() calls.
518 * @param src The source frame. The data buffers must be allocated, but the
519 * frame data does not have to be ready at this point. Data
520 * availability is then signalled by sws_send_slice().
521 * @return 0 on success, a negative AVERROR code on failure
522 *
523 * @see sws_frame_end()
524 */
525int sws_frame_start(SwsContext *c, AVFrame *dst, const AVFrame *src);
526
527/**
528 * Finish the scaling process for a pair of source/destination frames previously
529 * submitted with sws_frame_start(). Must be called after all sws_send_slice()
530 * and sws_receive_slice() calls are done, before any new sws_frame_start()
531 * calls.
532 *
533 * @param c The scaling context
534 */
535void sws_frame_end(SwsContext *c);
536
537/**
538 * Indicate that a horizontal slice of input data is available in the source
539 * frame previously provided to sws_frame_start(). The slices may be provided in
540 * any order, but may not overlap. For vertically subsampled pixel formats, the
541 * slices must be aligned according to subsampling.
542 *
543 * @param c The scaling context
544 * @param slice_start first row of the slice
545 * @param slice_height number of rows in the slice
546 *
547 * @return a non-negative number on success, a negative AVERROR code on failure.
548 */
549int sws_send_slice(SwsContext *c, unsigned int slice_start,
550 unsigned int slice_height);
551
552/**
553 * Request a horizontal slice of the output data to be written into the frame
554 * previously provided to sws_frame_start().
555 *
556 * @param c The scaling context
557 * @param slice_start first row of the slice; must be a multiple of
558 * sws_receive_slice_alignment()
559 * @param slice_height number of rows in the slice; must be a multiple of
560 * sws_receive_slice_alignment(), except for the last slice
561 * (i.e. when slice_start+slice_height is equal to output
562 * frame height)
563 *
564 * @return a non-negative number if the data was successfully written into the output
565 * AVERROR(EAGAIN) if more input data needs to be provided before the
566 * output can be produced
567 * another negative AVERROR code on other kinds of scaling failure
568 */
569int sws_receive_slice(SwsContext *c, unsigned int slice_start,
570 unsigned int slice_height);
571
572/**
573 * Get the alignment required for slices. Requires a context that has been
574 * previously been initialized with sws_init_context().
575 *
576 * @param c The scaling context
577 * @return alignment required for output slices requested with sws_receive_slice().
578 * Slice offsets and sizes passed to sws_receive_slice() must be
579 * multiples of the value returned from this function.
580 */
581unsigned int sws_receive_slice_alignment(const SwsContext *c);
582
583/**
584 * @param c the scaling context
585 * @param dstRange flag indicating the while-black range of the output (1=jpeg / 0=mpeg)
586 * @param srcRange flag indicating the while-black range of the input (1=jpeg / 0=mpeg)
587 * @param table the yuv2rgb coefficients describing the output yuv space, normally ff_yuv2rgb_coeffs[x]
588 * @param inv_table the yuv2rgb coefficients describing the input yuv space, normally ff_yuv2rgb_coeffs[x]
589 * @param brightness 16.16 fixed point brightness correction
590 * @param contrast 16.16 fixed point contrast correction
591 * @param saturation 16.16 fixed point saturation correction
592 *
593 * @return A negative error code on error, non negative otherwise.
594 * If `LIBSWSCALE_VERSION_MAJOR < 7`, returns -1 if not supported.
595 */
596int sws_setColorspaceDetails(SwsContext *c, const int inv_table[4],
597 int srcRange, const int table[4], int dstRange,
598 int brightness, int contrast, int saturation);
599
600/**
601 * @return A negative error code on error, non negative otherwise.
602 * If `LIBSWSCALE_VERSION_MAJOR < 7`, returns -1 if not supported.
603 */
604int sws_getColorspaceDetails(SwsContext *c, int **inv_table,
605 int *srcRange, int **table, int *dstRange,
606 int *brightness, int *contrast, int *saturation);
607
608/**
609 * Allocate and return an uninitialized vector with length coefficients.
610 */
611SwsVector *sws_allocVec(int length);
612
613/**
614 * Return a normalized Gaussian curve used to filter stuff
615 * quality = 3 is high quality, lower is lower quality.
616 */
617SwsVector *sws_getGaussianVec(double variance, double quality);
618
619/**
620 * Scale all the coefficients of a by the scalar value.
621 */
622void sws_scaleVec(SwsVector *a, double scalar);
623
624/**
625 * Scale all the coefficients of a so that their sum equals height.
626 */
627void sws_normalizeVec(SwsVector *a, double height);
628
629void sws_freeVec(SwsVector *a);
630
631SwsFilter *sws_getDefaultFilter(float lumaGBlur, float chromaGBlur,
632 float lumaSharpen, float chromaSharpen,
633 float chromaHShift, float chromaVShift,
634 int verbose);
635void sws_freeFilter(SwsFilter *filter);
636
637/**
638 * Check if context can be reused, otherwise reallocate a new one.
639 *
640 * If context is NULL, just calls sws_getContext() to get a new
641 * context. Otherwise, checks if the parameters are the ones already
642 * saved in context. If that is the case, returns the current
643 * context. Otherwise, frees context and gets a new context with
644 * the new parameters.
645 *
646 * Be warned that srcFilter and dstFilter are not checked, they
647 * are assumed to remain the same.
648 */
649SwsContext *sws_getCachedContext(SwsContext *context, int srcW, int srcH,
650 enum AVPixelFormat srcFormat, int dstW, int dstH,
651 enum AVPixelFormat dstFormat, int flags,
652 SwsFilter *srcFilter, SwsFilter *dstFilter,
653 const double *param);
654
655/**
656 * Convert an 8-bit paletted frame into a frame with a color depth of 32 bits.
657 *
658 * The output frame will have the same packed format as the palette.
659 *
660 * @param src source frame buffer
661 * @param dst destination frame buffer
662 * @param num_pixels number of pixels to convert
663 * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
664 */
665void sws_convertPalette8ToPacked32(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
666
667/**
668 * Convert an 8-bit paletted frame into a frame with a color depth of 24 bits.
669 *
670 * With the palette format "ABCD", the destination frame ends up with the format "ABC".
671 *
672 * @param src source frame buffer
673 * @param dst destination frame buffer
674 * @param num_pixels number of pixels to convert
675 * @param palette array with [256] entries, which must match color arrangement (RGB or BGR) of src
676 */
677void sws_convertPalette8ToPacked24(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);
678
679/**
680 * @}
681 */
682
683#endif /* SWSCALE_SWSCALE_H */
684