FFmpeg
swscale.c
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1 /*
2  * Copyright (C) 2003-2011 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 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <inttypes.h>
25 #include <stdarg.h>
26 
27 #undef HAVE_AV_CONFIG_H
28 #include "libavutil/cpu.h"
29 #include "libavutil/imgutils.h"
30 #include "libavutil/mem.h"
31 #include "libavutil/avutil.h"
32 #include "libavutil/crc.h"
33 #include "libavutil/pixdesc.h"
34 #include "libavutil/lfg.h"
35 
36 #include "libswscale/swscale.h"
37 
38 /* HACK Duplicated from swscale_internal.h.
39  * Should be removed when a cleaner pixel format system exists. */
40 #define isGray(x) \
41  ((x) == AV_PIX_FMT_GRAY8 || \
42  (x) == AV_PIX_FMT_YA8 || \
43  (x) == AV_PIX_FMT_GRAY16BE || \
44  (x) == AV_PIX_FMT_GRAY16LE || \
45  (x) == AV_PIX_FMT_YA16BE || \
46  (x) == AV_PIX_FMT_YA16LE)
47 #define hasChroma(x) \
48  (!(isGray(x) || \
49  (x) == AV_PIX_FMT_MONOBLACK || \
50  (x) == AV_PIX_FMT_MONOWHITE))
51 #define isALPHA(x) \
52  ((x) == AV_PIX_FMT_BGR32 || \
53  (x) == AV_PIX_FMT_BGR32_1 || \
54  (x) == AV_PIX_FMT_RGB32 || \
55  (x) == AV_PIX_FMT_RGB32_1 || \
56  (x) == AV_PIX_FMT_YUVA420P)
57 
58 static uint64_t getSSD(const uint8_t *src1, const uint8_t *src2,
59  int stride1, int stride2, int w, int h)
60 {
61  int x, y;
62  uint64_t ssd = 0;
63 
64  for (y = 0; y < h; y++) {
65  for (x = 0; x < w; x++) {
66  int d = src1[x + y * stride1] - src2[x + y * stride2];
67  ssd += d * d;
68  }
69  }
70  return ssd;
71 }
72 
73 struct Results {
74  uint64_t ssdY;
75  uint64_t ssdU;
76  uint64_t ssdV;
77  uint64_t ssdA;
78  uint32_t crc;
79 };
80 
81 // test by ref -> src -> dst -> out & compare out against ref
82 // ref & out are YV12
83 static int doTest(const uint8_t * const ref[4], int refStride[4], int w, int h,
84  enum AVPixelFormat srcFormat, enum AVPixelFormat dstFormat,
85  int srcW, int srcH, int dstW, int dstH, int flags,
86  struct Results *r)
87 {
89  const AVPixFmtDescriptor *desc_src = av_pix_fmt_desc_get(srcFormat);
90  const AVPixFmtDescriptor *desc_dst = av_pix_fmt_desc_get(dstFormat);
91  static enum AVPixelFormat cur_srcFormat;
92  static int cur_srcW, cur_srcH;
93  static const uint8_t *src[4];
94  static int srcStride[4];
95  uint8_t *dst[4] = { 0 };
96  uint8_t *out[4] = { 0 };
97  int dstStride[4] = {0};
98  int i;
99  uint64_t ssdY, ssdU = 0, ssdV = 0, ssdA = 0;
100  struct SwsContext *dstContext = NULL, *outContext = NULL;
101  uint32_t crc = 0;
102  int res = 0;
103 
104  if (cur_srcFormat != srcFormat || cur_srcW != srcW || cur_srcH != srcH) {
105  struct SwsContext *srcContext = NULL;
106  int p;
107 
108  for (p = 0; p < 4; p++)
109  av_freep(&src[p]);
110 
111  res = av_image_fill_linesizes(srcStride, srcFormat, srcW);
112  if (res < 0) {
113  fprintf(stderr, "av_image_fill_linesizes failed\n");
114  goto end;
115  }
116  for (p = 0; p < 4; p++) {
117  srcStride[p] = FFALIGN(srcStride[p], 16);
118  if (srcStride[p])
119  src[p] = av_mallocz(srcStride[p] * srcH + 16);
120  if (srcStride[p] && !src[p]) {
121  perror("Malloc");
122  res = -1;
123  goto end;
124  }
125  }
126  srcContext = sws_getContext(w, h, AV_PIX_FMT_YUVA420P, srcW, srcH,
128  if (!srcContext) {
129  fprintf(stderr, "Failed to get %s ---> %s\n",
130  desc_yuva420p->name,
131  desc_src->name);
132  res = -1;
133  goto end;
134  }
135  sws_scale(srcContext, ref, refStride, 0, h,
136  (uint8_t * const *) src, srcStride);
137  sws_freeContext(srcContext);
138 
139  cur_srcFormat = srcFormat;
140  cur_srcW = srcW;
141  cur_srcH = srcH;
142  }
143 
144  res = av_image_fill_linesizes(dstStride, dstFormat, dstW);
145  if (res < 0) {
146  fprintf(stderr, "av_image_fill_linesizes failed\n");
147  goto end;
148  }
149 
150  for (i = 0; i < 4; i++) {
151  /* Image buffers passed into libswscale can be allocated any way you
152  * prefer, as long as they're aligned enough for the architecture, and
153  * they're freed appropriately (such as using av_free for buffers
154  * allocated with av_malloc). */
155  /* An extra 16 bytes is being allocated because some scalers may write
156  * out of bounds. */
157  dstStride[i] = FFALIGN(dstStride[i], 16);
158  if (dstStride[i])
159  dst[i] = av_mallocz(dstStride[i] * dstH + 16);
160  if (dstStride[i] && !dst[i]) {
161  perror("Malloc");
162  res = -1;
163 
164  goto end;
165  }
166  }
167 
168  dstContext = sws_getContext(srcW, srcH, srcFormat, dstW, dstH, dstFormat,
169  flags, NULL, NULL, NULL);
170  if (!dstContext) {
171  fprintf(stderr, "Failed to get %s ---> %s\n",
172  desc_src->name, desc_dst->name);
173  res = -1;
174  goto end;
175  }
176 
177  printf(" %s %dx%d -> %s %3dx%3d flags=%2d",
178  desc_src->name, srcW, srcH,
179  desc_dst->name, dstW, dstH,
180  flags);
181  fflush(stdout);
182 
183  sws_scale(dstContext, (const uint8_t * const*)src, srcStride, 0, srcH, dst, dstStride);
184 
185  for (i = 0; i < 4 && dstStride[i]; i++)
186  crc = av_crc(av_crc_get_table(AV_CRC_32_IEEE), crc, dst[i],
187  dstStride[i] * dstH);
188 
189  if (r && crc == r->crc) {
190  ssdY = r->ssdY;
191  ssdU = r->ssdU;
192  ssdV = r->ssdV;
193  ssdA = r->ssdA;
194  } else {
195  for (i = 0; i < 4; i++) {
196  refStride[i] = FFALIGN(refStride[i], 16);
197  if (refStride[i])
198  out[i] = av_mallocz(refStride[i] * h);
199  if (refStride[i] && !out[i]) {
200  perror("Malloc");
201  res = -1;
202  goto end;
203  }
204  }
205  outContext = sws_getContext(dstW, dstH, dstFormat, w, h,
207  NULL, NULL, NULL);
208  if (!outContext) {
209  fprintf(stderr, "Failed to get %s ---> %s\n",
210  desc_dst->name,
211  desc_yuva420p->name);
212  res = -1;
213  goto end;
214  }
215  sws_scale(outContext, (const uint8_t * const *) dst, dstStride, 0, dstH,
216  out, refStride);
217 
218  ssdY = getSSD(ref[0], out[0], refStride[0], refStride[0], w, h);
220  //FIXME check that output is really gray
221  ssdU = getSSD(ref[1], out[1], refStride[1], refStride[1],
222  (w + 1) >> 1, (h + 1) >> 1);
223  ssdV = getSSD(ref[2], out[2], refStride[2], refStride[2],
224  (w + 1) >> 1, (h + 1) >> 1);
225  }
227  ssdA = getSSD(ref[3], out[3], refStride[3], refStride[3], w, h);
228 
229  ssdY /= w * h;
230  ssdU /= w * h / 4;
231  ssdV /= w * h / 4;
232  ssdA /= w * h;
233 
234  sws_freeContext(outContext);
235 
236  for (i = 0; i < 4; i++)
237  if (refStride[i])
238  av_free(out[i]);
239  }
240 
241  printf(" CRC=%08x SSD=%5"PRId64 ",%5"PRId64 ",%5"PRId64 ",%5"PRId64 "\n",
242  crc, ssdY, ssdU, ssdV, ssdA);
243 
244 end:
245  sws_freeContext(dstContext);
246 
247  for (i = 0; i < 4; i++)
248  if (dstStride[i])
249  av_free(dst[i]);
250 
251  return !!res;
252 }
253 
254 static void selfTest(const uint8_t * const ref[4], int refStride[4],
255  int w, int h,
256  enum AVPixelFormat srcFormat_in,
257  enum AVPixelFormat dstFormat_in)
258 {
260  SWS_X, SWS_POINT, SWS_AREA, 0 };
261  const int srcW = w;
262  const int srcH = h;
263  const int dstW[] = { srcW - srcW / 3, srcW, srcW + srcW / 3, 0 };
264  const int dstH[] = { srcH - srcH / 3, srcH, srcH + srcH / 3, 0 };
266  const AVPixFmtDescriptor *desc_src, *desc_dst;
267 
268  for (srcFormat = srcFormat_in != AV_PIX_FMT_NONE ? srcFormat_in : 0;
272  continue;
273 
274  desc_src = av_pix_fmt_desc_get(srcFormat);
275 
276  for (dstFormat = dstFormat_in != AV_PIX_FMT_NONE ? dstFormat_in : 0;
278  int i, j, k;
279  int res = 0;
280 
283  continue;
284 
285  desc_dst = av_pix_fmt_desc_get(dstFormat);
286 
287  printf("%s -> %s\n", desc_src->name, desc_dst->name);
288  fflush(stdout);
289 
290  for (k = 0; flags[k] && !res; k++)
291  for (i = 0; dstW[i] && !res; i++)
292  for (j = 0; dstH[j] && !res; j++)
293  res = doTest(ref, refStride, w, h,
295  srcW, srcH, dstW[i], dstH[j], flags[k],
296  NULL);
297  if (dstFormat_in != AV_PIX_FMT_NONE)
298  break;
299  }
300  if (srcFormat_in != AV_PIX_FMT_NONE)
301  break;
302  }
303 }
304 
305 static int fileTest(const uint8_t * const ref[4], int refStride[4],
306  int w, int h, FILE *fp,
307  enum AVPixelFormat srcFormat_in,
308  enum AVPixelFormat dstFormat_in)
309 {
310  char buf[256];
311 
312  while (fgets(buf, sizeof(buf), fp)) {
313  struct Results r;
314  enum AVPixelFormat srcFormat;
315  char srcStr[21];
316  int srcW = 0, srcH = 0;
317  enum AVPixelFormat dstFormat;
318  char dstStr[21];
319  int dstW = 0, dstH = 0;
320  int flags;
321  int ret;
322 
323  ret = sscanf(buf,
324  " %20s %dx%d -> %20s %dx%d flags=%d CRC=%x"
325  " SSD=%"SCNu64 ", %"SCNu64 ", %"SCNu64 ", %"SCNu64 "\n",
326  srcStr, &srcW, &srcH, dstStr, &dstW, &dstH,
327  &flags, &r.crc, &r.ssdY, &r.ssdU, &r.ssdV, &r.ssdA);
328  if (ret != 12) {
329  srcStr[0] = dstStr[0] = 0;
330  ret = sscanf(buf, "%20s -> %20s\n", srcStr, dstStr);
331  }
332 
333  srcFormat = av_get_pix_fmt(srcStr);
334  dstFormat = av_get_pix_fmt(dstStr);
335 
336  if (srcFormat == AV_PIX_FMT_NONE || dstFormat == AV_PIX_FMT_NONE ||
337  srcW > 8192U || srcH > 8192U || dstW > 8192U || dstH > 8192U) {
338  fprintf(stderr, "malformed input file\n");
339  return -1;
340  }
341  if ((srcFormat_in != AV_PIX_FMT_NONE && srcFormat_in != srcFormat) ||
342  (dstFormat_in != AV_PIX_FMT_NONE && dstFormat_in != dstFormat))
343  continue;
344  if (ret != 12) {
345  printf("%s", buf);
346  continue;
347  }
348 
349  doTest(ref, refStride, w, h,
350  srcFormat, dstFormat,
351  srcW, srcH, dstW, dstH, flags,
352  &r);
353  }
354 
355  return 0;
356 }
357 
358 #define W 96
359 #define H 96
360 
361 int main(int argc, char **argv)
362 {
363  enum AVPixelFormat srcFormat = AV_PIX_FMT_NONE;
364  enum AVPixelFormat dstFormat = AV_PIX_FMT_NONE;
365  uint8_t *rgb_data = av_malloc(W * H * 4);
366  const uint8_t * const rgb_src[4] = { rgb_data, NULL, NULL, NULL };
367  int rgb_stride[4] = { 4 * W, 0, 0, 0 };
368  uint8_t *data = av_malloc(4 * W * H);
369  const uint8_t * const src[4] = { data, data + W * H, data + W * H * 2, data + W * H * 3 };
370  int stride[4] = { W, W, W, W };
371  int x, y;
372  struct SwsContext *sws;
373  AVLFG rand;
374  int res = -1;
375  int i;
376  FILE *fp = NULL;
377 
378  if (!rgb_data || !data)
379  return -1;
380 
381  for (i = 1; i < argc; i += 2) {
382  if (argv[i][0] != '-' || i + 1 == argc)
383  goto bad_option;
384  if (!strcmp(argv[i], "-ref")) {
385  fp = fopen(argv[i + 1], "r");
386  if (!fp) {
387  fprintf(stderr, "could not open '%s'\n", argv[i + 1]);
388  goto error;
389  }
390  } else if (!strcmp(argv[i], "-cpuflags")) {
391  unsigned flags = av_get_cpu_flags();
392  int ret = av_parse_cpu_caps(&flags, argv[i + 1]);
393  if (ret < 0) {
394  fprintf(stderr, "invalid cpu flags %s\n", argv[i + 1]);
395  return ret;
396  }
398  } else if (!strcmp(argv[i], "-src")) {
399  srcFormat = av_get_pix_fmt(argv[i + 1]);
400  if (srcFormat == AV_PIX_FMT_NONE) {
401  fprintf(stderr, "invalid pixel format %s\n", argv[i + 1]);
402  return -1;
403  }
404  } else if (!strcmp(argv[i], "-dst")) {
405  dstFormat = av_get_pix_fmt(argv[i + 1]);
406  if (dstFormat == AV_PIX_FMT_NONE) {
407  fprintf(stderr, "invalid pixel format %s\n", argv[i + 1]);
408  return -1;
409  }
410  } else {
411 bad_option:
412  fprintf(stderr, "bad option or argument missing (%s)\n", argv[i]);
413  goto error;
414  }
415  }
416 
417  sws = sws_getContext(W / 12, H / 12, AV_PIX_FMT_RGB32, W, H,
419 
420  av_lfg_init(&rand, 1);
421 
422  for (y = 0; y < H; y++)
423  for (x = 0; x < W * 4; x++)
424  rgb_data[ x + y * 4 * W] = av_lfg_get(&rand);
425  res = sws_scale(sws, rgb_src, rgb_stride, 0, H / 12, (uint8_t * const *) src, stride);
426  if (res < 0 || res != H) {
427  res = -1;
428  goto error;
429  }
430  sws_freeContext(sws);
431  av_free(rgb_data);
432 
433  if(fp) {
434  res = fileTest(src, stride, W, H, fp, srcFormat, dstFormat);
435  fclose(fp);
436  } else {
438  res = 0;
439  }
440 error:
441  av_free(data);
442 
443  return res;
444 }
error
static void error(const char *err)
Definition: target_bsf_fuzzer.c:31
av_force_cpu_flags
void av_force_cpu_flags(int arg)
Disables cpu detection and forces the specified flags.
Definition: cpu.c:75
AVPixelFormat
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
r
const char * r
Definition: vf_curves.c:126
SwsContext::dstW
int dstW
Width of destination luma/alpha planes.
Definition: swscale_internal.h:514
out
FILE * out
Definition: movenc.c:54
sws_isSupportedOutput
#define sws_isSupportedOutput(x)
av_lfg_init
av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:32
selfTest
static void selfTest(const uint8_t *const ref[4], int refStride[4], int w, int h, enum AVPixelFormat srcFormat_in, enum AVPixelFormat dstFormat_in)
Definition: swscale.c:254
av_pix_fmt_desc_get
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2964
src1
const pixel * src1
Definition: h264pred_template.c:421
Results::crc
uint32_t crc
Definition: swscale.c:78
pixdesc.h
W
#define W
Definition: swscale.c:358
w
uint8_t w
Definition: llviddspenc.c:38
AVPixFmtDescriptor::name
const char * name
Definition: pixdesc.h:70
Results::ssdA
uint64_t ssdA
Definition: swscale.c:77
data
const char data[16]
Definition: mxf.c:148
sws_scale
int attribute_align_arg sws_scale(struct SwsContext *c, const uint8_t *const srcSlice[], const int srcStride[], int srcSliceY, int srcSliceH, uint8_t *const dst[], const int dstStride[])
swscale wrapper, so we don't need to export the SwsContext.
Definition: swscale.c:1205
av_get_cpu_flags
int av_get_cpu_flags(void)
Return the flags which specify extensions supported by the CPU.
Definition: cpu.c:103
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:30
AV_PIX_FMT_NB
@ AV_PIX_FMT_NB
number of pixel formats, DO NOT USE THIS if you want to link with shared libav* because the number of...
Definition: pixfmt.h:432
crc.h
SWS_FAST_BILINEAR
#define SWS_FAST_BILINEAR
Definition: swscale.h:65
av_parse_cpu_caps
int av_parse_cpu_caps(unsigned *flags, const char *s)
Parse CPU caps from a string and update the given AV_CPU_* flags based on that.
Definition: cpu.c:113
hasChroma
#define hasChroma(x)
Definition: swscale.c:47
SWS_POINT
#define SWS_POINT
Definition: swscale.h:69
Results::ssdU
uint64_t ssdU
Definition: swscale.c:75
SwsContext::srcFormat
enum AVPixelFormat srcFormat
Source pixel format.
Definition: swscale_internal.h:331
av_image_fill_linesizes
int av_image_fill_linesizes(int linesizes[4], enum AVPixelFormat pix_fmt, int width)
Fill plane linesizes for an image with pixel format pix_fmt and width width.
Definition: imgutils.c:89
AV_PIX_FMT_YUVA420P
@ AV_PIX_FMT_YUVA420P
planar YUV 4:2:0, 20bpp, (1 Cr & Cb sample per 2x2 Y & A samples)
Definition: pixfmt.h:101
av_lfg_get
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:53
lfg.h
getSSD
static uint64_t getSSD(const uint8_t *src1, const uint8_t *src2, int stride1, int stride2, int w, int h)
Definition: swscale.c:58
SwsContext::dstFormat
enum AVPixelFormat dstFormat
Destination pixel format.
Definition: swscale_internal.h:330
Results
Definition: swscale.c:73
NULL
#define NULL
Definition: coverity.c:32
Results::ssdV
uint64_t ssdV
Definition: swscale.c:76
H
#define H
Definition: swscale.c:359
fp
#define fp
Definition: regdef.h:44
SWS_X
#define SWS_X
Definition: swscale.h:68
doTest
static int doTest(const uint8_t *const ref[4], int refStride[4], int w, int h, enum AVPixelFormat srcFormat, enum AVPixelFormat dstFormat, int srcW, int srcH, int dstW, int dstH, int flags, struct Results *r)
Definition: swscale.c:83
AVLFG
Context structure for the Lagged Fibonacci PRNG.
Definition: lfg.h:33
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:2096
cpu.h
SwsContext::srcH
int srcH
Height of source luma/alpha planes.
Definition: swscale_internal.h:322
printf
printf("static const uint8_t my_array[100] = {\n")
AV_PIX_FMT_RGB32
#define AV_PIX_FMT_RGB32
Definition: pixfmt.h:441
av_crc_get_table
const AVCRC * av_crc_get_table(AVCRCId crc_id)
Get an initialized standard CRC table.
Definition: crc.c:374
sws_isSupportedInput
#define sws_isSupportedInput(x)
isALPHA
#define isALPHA(x)
Definition: swscale.c:51
SwsContext::srcW
int srcW
Width of source luma/alpha planes.
Definition: swscale_internal.h:321
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:255
src2
const pixel * src2
Definition: h264pred_template.c:422
av_mallocz
void * av_mallocz(size_t size)
Allocate a memory block with alignment suitable for all memory accesses (including vectors if availab...
Definition: mem.c:254
AV_CRC_32_IEEE
@ AV_CRC_32_IEEE
Definition: crc.h:52
stride
#define stride
Definition: h264pred_template.c:537
ret
ret
Definition: filter_design.txt:187
U
#define U(x)
Definition: vpx_arith.h:37
av_get_pix_fmt
enum AVPixelFormat av_get_pix_fmt(const char *name)
Return the pixel format corresponding to name.
Definition: pixdesc.c:2896
Results::ssdY
uint64_t ssdY
Definition: swscale.c:74
main
int main(int argc, char **argv)
Definition: swscale.c:361
sws_freeContext
void sws_freeContext(struct SwsContext *swsContext)
Free the swscaler context swsContext.
Definition: utils.c:2427
av_crc
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length)
Calculate the CRC of a block.
Definition: crc.c:392
AV_PIX_FMT_NONE
@ AV_PIX_FMT_NONE
Definition: pixfmt.h:65
ref
static int ref[MAX_W *MAX_W]
Definition: jpeg2000dwt.c:112
avutil.h
mem.h
AVPixFmtDescriptor
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:69
av_free
#define av_free(p)
Definition: tableprint_vlc.h:33
FFALIGN
#define FFALIGN(x, a)
Definition: macros.h:78
av_freep
#define av_freep(p)
Definition: tableprint_vlc.h:34
src
INIT_CLIP pixel * src
Definition: h264pred_template.c:418
d
d
Definition: ffmpeg_filter.c:368
imgutils.h
flags
#define flags(name, subs,...)
Definition: cbs_av1.c:474
fileTest
static int fileTest(const uint8_t *const ref[4], int refStride[4], int w, int h, FILE *fp, enum AVPixelFormat srcFormat_in, enum AVPixelFormat dstFormat_in)
Definition: swscale.c:305
h
h
Definition: vp9dsp_template.c:2038
SWS_BILINEAR
#define SWS_BILINEAR
Definition: swscale.h:66
SWS_AREA
#define SWS_AREA
Definition: swscale.h:70
SwsContext
Definition: swscale_internal.h:299
SwsContext::dstH
int dstH
Height of destination luma/alpha planes.
Definition: swscale_internal.h:323
SWS_BICUBIC
#define SWS_BICUBIC
Definition: swscale.h:67
swscale.h