This file is indexed.

/usr/include/x86_64-linux-gnu/libswscale/swscale.h is in libswscale-dev 7:3.2.12-1~deb9u1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
/*
 * Copyright (C) 2001-2011 Michael Niedermayer <michaelni@gmx.at>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef SWSCALE_SWSCALE_H
#define SWSCALE_SWSCALE_H

/**
 * @file
 * @ingroup libsws
 * external API header
 */

#include <stdint.h>

#include "libavutil/avutil.h"
#include "libavutil/log.h"
#include "libavutil/pixfmt.h"
#include "version.h"

/**
 * @defgroup libsws libswscale
 * Color conversion and scaling library.
 *
 * @{
 *
 * Return the LIBSWSCALE_VERSION_INT constant.
 */
unsigned swscale_version(void);

/**
 * Return the libswscale build-time configuration.
 */
const char *swscale_configuration(void);

/**
 * Return the libswscale license.
 */
const char *swscale_license(void);

/* values for the flags, the stuff on the command line is different */
#define SWS_FAST_BILINEAR     1
#define SWS_BILINEAR          2
#define SWS_BICUBIC           4
#define SWS_X                 8
#define SWS_POINT          0x10
#define SWS_AREA           0x20
#define SWS_BICUBLIN       0x40
#define SWS_GAUSS          0x80
#define SWS_SINC          0x100
#define SWS_LANCZOS       0x200
#define SWS_SPLINE        0x400

#define SWS_SRC_V_CHR_DROP_MASK     0x30000
#define SWS_SRC_V_CHR_DROP_SHIFT    16

#define SWS_PARAM_DEFAULT           123456

#define SWS_PRINT_INFO              0x1000

//the following 3 flags are not completely implemented
//internal chrominance subsampling info
#define SWS_FULL_CHR_H_INT    0x2000
//input subsampling info
#define SWS_FULL_CHR_H_INP    0x4000
#define SWS_DIRECT_BGR        0x8000
#define SWS_ACCURATE_RND      0x40000
#define SWS_BITEXACT          0x80000
#define SWS_ERROR_DIFFUSION  0x800000

#define SWS_MAX_REDUCE_CUTOFF 0.002

#define SWS_CS_ITU709         1
#define SWS_CS_FCC            4
#define SWS_CS_ITU601         5
#define SWS_CS_ITU624         5
#define SWS_CS_SMPTE170M      5
#define SWS_CS_SMPTE240M      7
#define SWS_CS_DEFAULT        5
#define SWS_CS_BT2020         9

/**
 * Return a pointer to yuv<->rgb coefficients for the given colorspace
 * suitable for sws_setColorspaceDetails().
 *
 * @param colorspace One of the SWS_CS_* macros. If invalid,
 * SWS_CS_DEFAULT is used.
 */
const int *sws_getCoefficients(int colorspace);

// when used for filters they must have an odd number of elements
// coeffs cannot be shared between vectors
typedef struct SwsVector {
    double *coeff;              ///< pointer to the list of coefficients
    int length;                 ///< number of coefficients in the vector
} SwsVector;

// vectors can be shared
typedef struct SwsFilter {
    SwsVector *lumH;
    SwsVector *lumV;
    SwsVector *chrH;
    SwsVector *chrV;
} SwsFilter;

struct SwsContext;

/**
 * Return a positive value if pix_fmt is a supported input format, 0
 * otherwise.
 */
int sws_isSupportedInput(enum AVPixelFormat pix_fmt);

/**
 * Return a positive value if pix_fmt is a supported output format, 0
 * otherwise.
 */
int sws_isSupportedOutput(enum AVPixelFormat pix_fmt);

/**
 * @param[in]  pix_fmt the pixel format
 * @return a positive value if an endianness conversion for pix_fmt is
 * supported, 0 otherwise.
 */
int sws_isSupportedEndiannessConversion(enum AVPixelFormat pix_fmt);

/**
 * Allocate an empty SwsContext. This must be filled and passed to
 * sws_init_context(). For filling see AVOptions, options.c and
 * sws_setColorspaceDetails().
 */
struct SwsContext *sws_alloc_context(void);

/**
 * Initialize the swscaler context sws_context.
 *
 * @return zero or positive value on success, a negative value on
 * error
 */
av_warn_unused_result
int sws_init_context(struct SwsContext *sws_context, SwsFilter *srcFilter, SwsFilter *dstFilter);

/**
 * Free the swscaler context swsContext.
 * If swsContext is NULL, then does nothing.
 */
void sws_freeContext(struct SwsContext *swsContext);

/**
 * Allocate and return an SwsContext. You need it to perform
 * scaling/conversion operations using sws_scale().
 *
 * @param srcW the width of the source image
 * @param srcH the height of the source image
 * @param srcFormat the source image format
 * @param dstW the width of the destination image
 * @param dstH the height of the destination image
 * @param dstFormat the destination image format
 * @param flags specify which algorithm and options to use for rescaling
 * @param param extra parameters to tune the used scaler
 *              For SWS_BICUBIC param[0] and [1] tune the shape of the basis
 *              function, param[0] tunes f(1) and param[1] f´(1)
 *              For SWS_GAUSS param[0] tunes the exponent and thus cutoff
 *              frequency
 *              For SWS_LANCZOS param[0] tunes the width of the window function
 * @return a pointer to an allocated context, or NULL in case of error
 * @note this function is to be removed after a saner alternative is
 *       written
 */
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);

/**
 * Scale the image slice in srcSlice and put the resulting scaled
 * slice in the image in dst. A slice is a sequence of consecutive
 * rows in an image.
 *
 * Slices have to be provided in sequential order, either in
 * top-bottom or bottom-top order. If slices are provided in
 * non-sequential order the behavior of the function is undefined.
 *
 * @param c         the scaling context previously created with
 *                  sws_getContext()
 * @param srcSlice  the array containing the pointers to the planes of
 *                  the source slice
 * @param srcStride the array containing the strides for each plane of
 *                  the source image
 * @param srcSliceY the position in the source image of the slice to
 *                  process, that is the number (counted starting from
 *                  zero) in the image of the first row of the slice
 * @param srcSliceH the height of the source slice, that is the number
 *                  of rows in the slice
 * @param dst       the array containing the pointers to the planes of
 *                  the destination image
 * @param dstStride the array containing the strides for each plane of
 *                  the destination image
 * @return          the height of the output slice
 */
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[]);

/**
 * @param dstRange flag indicating the while-black range of the output (1=jpeg / 0=mpeg)
 * @param srcRange flag indicating the while-black range of the input (1=jpeg / 0=mpeg)
 * @param table the yuv2rgb coefficients describing the output yuv space, normally ff_yuv2rgb_coeffs[x]
 * @param inv_table the yuv2rgb coefficients describing the input yuv space, normally ff_yuv2rgb_coeffs[x]
 * @param brightness 16.16 fixed point brightness correction
 * @param contrast 16.16 fixed point contrast correction
 * @param saturation 16.16 fixed point saturation correction
 * @return -1 if not supported
 */
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);

/**
 * @return -1 if not supported
 */
int sws_getColorspaceDetails(struct SwsContext *c, int **inv_table,
                             int *srcRange, int **table, int *dstRange,
                             int *brightness, int *contrast, int *saturation);

/**
 * Allocate and return an uninitialized vector with length coefficients.
 */
SwsVector *sws_allocVec(int length);

/**
 * Return a normalized Gaussian curve used to filter stuff
 * quality = 3 is high quality, lower is lower quality.
 */
SwsVector *sws_getGaussianVec(double variance, double quality);

/**
 * Scale all the coefficients of a by the scalar value.
 */
void sws_scaleVec(SwsVector *a, double scalar);

/**
 * Scale all the coefficients of a so that their sum equals height.
 */
void sws_normalizeVec(SwsVector *a, double height);

#if FF_API_SWS_VECTOR
attribute_deprecated SwsVector *sws_getConstVec(double c, int length);
attribute_deprecated SwsVector *sws_getIdentityVec(void);
attribute_deprecated void sws_convVec(SwsVector *a, SwsVector *b);
attribute_deprecated void sws_addVec(SwsVector *a, SwsVector *b);
attribute_deprecated void sws_subVec(SwsVector *a, SwsVector *b);
attribute_deprecated void sws_shiftVec(SwsVector *a, int shift);
attribute_deprecated SwsVector *sws_cloneVec(SwsVector *a);
attribute_deprecated void sws_printVec2(SwsVector *a, AVClass *log_ctx, int log_level);
#endif

void sws_freeVec(SwsVector *a);

SwsFilter *sws_getDefaultFilter(float lumaGBlur, float chromaGBlur,
                                float lumaSharpen, float chromaSharpen,
                                float chromaHShift, float chromaVShift,
                                int verbose);
void sws_freeFilter(SwsFilter *filter);

/**
 * Check if context can be reused, otherwise reallocate a new one.
 *
 * If context is NULL, just calls sws_getContext() to get a new
 * context. Otherwise, checks if the parameters are the ones already
 * saved in context. If that is the case, returns the current
 * context. Otherwise, frees context and gets a new context with
 * the new parameters.
 *
 * Be warned that srcFilter and dstFilter are not checked, they
 * are assumed to remain the same.
 */
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);

/**
 * Convert an 8-bit paletted frame into a frame with a color depth of 32 bits.
 *
 * The output frame will have the same packed format as the palette.
 *
 * @param src        source frame buffer
 * @param dst        destination frame buffer
 * @param num_pixels number of pixels to convert
 * @param palette    array with [256] entries, which must match color arrangement (RGB or BGR) of src
 */
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 24 bits.
 *
 * With the palette format "ABCD", the destination frame ends up with the format "ABC".
 *
 * @param src        source frame buffer
 * @param dst        destination frame buffer
 * @param num_pixels number of pixels to convert
 * @param palette    array with [256] entries, which must match color arrangement (RGB or BGR) of src
 */
void sws_convertPalette8ToPacked24(const uint8_t *src, uint8_t *dst, int num_pixels, const uint8_t *palette);

/**
 * Get the AVClass for swsContext. It can be used in combination with
 * AV_OPT_SEARCH_FAKE_OBJ for examining options.
 *
 * @see av_opt_find().
 */
const AVClass *sws_get_class(void);

/**
 * @}
 */

#endif /* SWSCALE_SWSCALE_H */