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vf_hue.c
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1 /*
2  * Copyright (c) 2003 Michael Niedermayer
3  * Copyright (c) 2012 Jeremy Tran
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 /**
23  * @file
24  * Apply a hue/saturation filter to the input video
25  * Ported from MPlayer libmpcodecs/vf_hue.c.
26  */
27 
28 #include <float.h>
29 #include "libavutil/eval.h"
30 #include "libavutil/imgutils.h"
31 #include "libavutil/opt.h"
32 #include "libavutil/pixdesc.h"
33 
34 #include "avfilter.h"
35 #include "formats.h"
36 #include "internal.h"
37 #include "video.h"
38 
39 #define SAT_MIN_VAL -10
40 #define SAT_MAX_VAL 10
41 
42 static const char *const var_names[] = {
43  "n", // frame count
44  "pts", // presentation timestamp expressed in AV_TIME_BASE units
45  "r", // frame rate
46  "t", // timestamp expressed in seconds
47  "tb", // timebase
48  NULL
49 };
50 
51 enum var_name {
58 };
59 
60 typedef struct {
61  const AVClass *class;
62  float hue_deg; /* hue expressed in degrees */
63  float hue; /* hue expressed in radians */
64  char *hue_deg_expr;
65  char *hue_expr;
68  float saturation;
71  float brightness;
74  int hsub;
75  int vsub;
76  int is_first;
79  double var_values[VAR_NB];
80  uint8_t lut_l[256];
81  uint8_t lut_u[256][256];
82  uint8_t lut_v[256][256];
83 } HueContext;
84 
85 #define OFFSET(x) offsetof(HueContext, x)
86 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
87 static const AVOption hue_options[] = {
88  { "h", "set the hue angle degrees expression", OFFSET(hue_deg_expr), AV_OPT_TYPE_STRING,
89  { .str = NULL }, .flags = FLAGS },
90  { "s", "set the saturation expression", OFFSET(saturation_expr), AV_OPT_TYPE_STRING,
91  { .str = "1" }, .flags = FLAGS },
92  { "H", "set the hue angle radians expression", OFFSET(hue_expr), AV_OPT_TYPE_STRING,
93  { .str = NULL }, .flags = FLAGS },
94  { "b", "set the brightness expression", OFFSET(brightness_expr), AV_OPT_TYPE_STRING,
95  { .str = "0" }, .flags = FLAGS },
96  { NULL }
97 };
98 
100 
101 static inline void compute_sin_and_cos(HueContext *hue)
102 {
103  /*
104  * Scale the value to the norm of the resulting (U,V) vector, that is
105  * the saturation.
106  * This will be useful in the apply_lut function.
107  */
108  hue->hue_sin = rint(sin(hue->hue) * (1 << 16) * hue->saturation);
109  hue->hue_cos = rint(cos(hue->hue) * (1 << 16) * hue->saturation);
110 }
111 
112 static inline void create_luma_lut(HueContext *h)
113 {
114  const float b = h->brightness;
115  int i;
116 
117  for (i = 0; i < 256; i++) {
118  h->lut_l[i] = av_clip_uint8(i + b * 25.5);
119  }
120 }
121 
122 static inline void create_chrominance_lut(HueContext *h, const int32_t c,
123  const int32_t s)
124 {
125  int32_t i, j, u, v, new_u, new_v;
126 
127  /*
128  * If we consider U and V as the components of a 2D vector then its angle
129  * is the hue and the norm is the saturation
130  */
131  for (i = 0; i < 256; i++) {
132  for (j = 0; j < 256; j++) {
133  /* Normalize the components from range [16;140] to [-112;112] */
134  u = i - 128;
135  v = j - 128;
136  /*
137  * Apply the rotation of the vector : (c * u) - (s * v)
138  * (s * u) + (c * v)
139  * De-normalize the components (without forgetting to scale 128
140  * by << 16)
141  * Finally scale back the result by >> 16
142  */
143  new_u = ((c * u) - (s * v) + (1 << 15) + (128 << 16)) >> 16;
144  new_v = ((s * u) + (c * v) + (1 << 15) + (128 << 16)) >> 16;
145 
146  /* Prevent a potential overflow */
147  h->lut_u[i][j] = av_clip_uint8(new_u);
148  h->lut_v[i][j] = av_clip_uint8(new_v);
149  }
150  }
151 }
152 
153 static int set_expr(AVExpr **pexpr_ptr, char **expr_ptr,
154  const char *expr, const char *option, void *log_ctx)
155 {
156  int ret;
157  AVExpr *new_pexpr;
158  char *new_expr;
159 
160  new_expr = av_strdup(expr);
161  if (!new_expr)
162  return AVERROR(ENOMEM);
163  ret = av_expr_parse(&new_pexpr, expr, var_names,
164  NULL, NULL, NULL, NULL, 0, log_ctx);
165  if (ret < 0) {
166  av_log(log_ctx, AV_LOG_ERROR,
167  "Error when evaluating the expression '%s' for %s\n",
168  expr, option);
169  av_free(new_expr);
170  return ret;
171  }
172 
173  if (*pexpr_ptr)
174  av_expr_free(*pexpr_ptr);
175  *pexpr_ptr = new_pexpr;
176  av_freep(expr_ptr);
177  *expr_ptr = new_expr;
178 
179  return 0;
180 }
181 
182 static av_cold int init(AVFilterContext *ctx)
183 {
184  HueContext *hue = ctx->priv;
185  int ret;
186 
187  if (hue->hue_expr && hue->hue_deg_expr) {
188  av_log(ctx, AV_LOG_ERROR,
189  "H and h options are incompatible and cannot be specified "
190  "at the same time\n");
191  return AVERROR(EINVAL);
192  }
193 
194 #define SET_EXPR(expr, option) \
195  if (hue->expr##_expr) do { \
196  ret = set_expr(&hue->expr##_pexpr, &hue->expr##_expr, \
197  hue->expr##_expr, option, ctx); \
198  if (ret < 0) \
199  return ret; \
200  } while (0)
201  SET_EXPR(brightness, "b");
202  SET_EXPR(saturation, "s");
203  SET_EXPR(hue_deg, "h");
204  SET_EXPR(hue, "H");
205 #undef SET_EXPR
206 
207  av_log(ctx, AV_LOG_VERBOSE,
208  "H_expr:%s h_deg_expr:%s s_expr:%s b_expr:%s\n",
209  hue->hue_expr, hue->hue_deg_expr, hue->saturation_expr, hue->brightness_expr);
210  compute_sin_and_cos(hue);
211  hue->is_first = 1;
212 
213  return 0;
214 }
215 
216 static av_cold void uninit(AVFilterContext *ctx)
217 {
218  HueContext *hue = ctx->priv;
219 
222  av_expr_free(hue->hue_pexpr);
224 }
225 
227 {
228  static const enum AVPixelFormat pix_fmts[] = {
235  };
236  AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
237  if (!fmts_list)
238  return AVERROR(ENOMEM);
239  return ff_set_common_formats(ctx, fmts_list);
240 }
241 
242 static int config_props(AVFilterLink *inlink)
243 {
244  HueContext *hue = inlink->dst->priv;
245  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
246 
247  hue->hsub = desc->log2_chroma_w;
248  hue->vsub = desc->log2_chroma_h;
249 
250  hue->var_values[VAR_N] = 0;
251  hue->var_values[VAR_TB] = av_q2d(inlink->time_base);
252  hue->var_values[VAR_R] = inlink->frame_rate.num == 0 || inlink->frame_rate.den == 0 ?
253  NAN : av_q2d(inlink->frame_rate);
254 
255  return 0;
256 }
257 
259  uint8_t *ldst, const int dst_linesize,
260  uint8_t *lsrc, const int src_linesize,
261  int w, int h)
262 {
263  int i;
264 
265  while (h--) {
266  for (i = 0; i < w; i++)
267  ldst[i] = s->lut_l[lsrc[i]];
268 
269  lsrc += src_linesize;
270  ldst += dst_linesize;
271  }
272 }
273 
274 static void apply_lut(HueContext *s,
275  uint8_t *udst, uint8_t *vdst, const int dst_linesize,
276  uint8_t *usrc, uint8_t *vsrc, const int src_linesize,
277  int w, int h)
278 {
279  int i;
280 
281  while (h--) {
282  for (i = 0; i < w; i++) {
283  const int u = usrc[i];
284  const int v = vsrc[i];
285 
286  udst[i] = s->lut_u[u][v];
287  vdst[i] = s->lut_v[u][v];
288  }
289 
290  usrc += src_linesize;
291  vsrc += src_linesize;
292  udst += dst_linesize;
293  vdst += dst_linesize;
294  }
295 }
296 
297 #define TS2D(ts) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts))
298 #define TS2T(ts, tb) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts) * av_q2d(tb))
299 
300 static int filter_frame(AVFilterLink *inlink, AVFrame *inpic)
301 {
302  HueContext *hue = inlink->dst->priv;
303  AVFilterLink *outlink = inlink->dst->outputs[0];
304  AVFrame *outpic;
305  const int32_t old_hue_sin = hue->hue_sin, old_hue_cos = hue->hue_cos;
306  const float old_brightness = hue->brightness;
307  int direct = 0;
308 
309  if (av_frame_is_writable(inpic)) {
310  direct = 1;
311  outpic = inpic;
312  } else {
313  outpic = ff_get_video_buffer(outlink, outlink->w, outlink->h);
314  if (!outpic) {
315  av_frame_free(&inpic);
316  return AVERROR(ENOMEM);
317  }
318  av_frame_copy_props(outpic, inpic);
319  }
320 
321  hue->var_values[VAR_N] = inlink->frame_count;
322  hue->var_values[VAR_T] = TS2T(inpic->pts, inlink->time_base);
323  hue->var_values[VAR_PTS] = TS2D(inpic->pts);
324 
325  if (hue->saturation_expr) {
327 
328  if (hue->saturation < SAT_MIN_VAL || hue->saturation > SAT_MAX_VAL) {
329  hue->saturation = av_clip(hue->saturation, SAT_MIN_VAL, SAT_MAX_VAL);
330  av_log(inlink->dst, AV_LOG_WARNING,
331  "Saturation value not in range [%d,%d]: clipping value to %0.1f\n",
333  }
334  }
335 
336  if (hue->brightness_expr) {
338 
339  if (hue->brightness < -10 || hue->brightness > 10) {
340  hue->brightness = av_clipf(hue->brightness, -10, 10);
341  av_log(inlink->dst, AV_LOG_WARNING,
342  "Brightness value not in range [%d,%d]: clipping value to %0.1f\n",
343  -10, 10, hue->brightness);
344  }
345  }
346 
347  if (hue->hue_deg_expr) {
348  hue->hue_deg = av_expr_eval(hue->hue_deg_pexpr, hue->var_values, NULL);
349  hue->hue = hue->hue_deg * M_PI / 180;
350  } else if (hue->hue_expr) {
351  hue->hue = av_expr_eval(hue->hue_pexpr, hue->var_values, NULL);
352  hue->hue_deg = hue->hue * 180 / M_PI;
353  }
354 
355  av_log(inlink->dst, AV_LOG_DEBUG,
356  "H:%0.1f*PI h:%0.1f s:%0.1f b:%0.f t:%0.1f n:%d\n",
357  hue->hue/M_PI, hue->hue_deg, hue->saturation, hue->brightness,
358  hue->var_values[VAR_T], (int)hue->var_values[VAR_N]);
359 
360  compute_sin_and_cos(hue);
361  if (hue->is_first || (old_hue_sin != hue->hue_sin || old_hue_cos != hue->hue_cos))
362  create_chrominance_lut(hue, hue->hue_cos, hue->hue_sin);
363 
364  if (hue->is_first || (old_brightness != hue->brightness && hue->brightness))
365  create_luma_lut(hue);
366 
367  if (!direct) {
368  if (!hue->brightness)
369  av_image_copy_plane(outpic->data[0], outpic->linesize[0],
370  inpic->data[0], inpic->linesize[0],
371  inlink->w, inlink->h);
372  if (inpic->data[3])
373  av_image_copy_plane(outpic->data[3], outpic->linesize[3],
374  inpic->data[3], inpic->linesize[3],
375  inlink->w, inlink->h);
376  }
377 
378  apply_lut(hue, outpic->data[1], outpic->data[2], outpic->linesize[1],
379  inpic->data[1], inpic->data[2], inpic->linesize[1],
380  FF_CEIL_RSHIFT(inlink->w, hue->hsub),
381  FF_CEIL_RSHIFT(inlink->h, hue->vsub));
382  if (hue->brightness)
383  apply_luma_lut(hue, outpic->data[0], outpic->linesize[0],
384  inpic->data[0], inpic->linesize[0], inlink->w, inlink->h);
385 
386  if (!direct)
387  av_frame_free(&inpic);
388 
389  hue->is_first = 0;
390  return ff_filter_frame(outlink, outpic);
391 }
392 
393 static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
394  char *res, int res_len, int flags)
395 {
396  HueContext *hue = ctx->priv;
397  int ret;
398 
399 #define SET_EXPR(expr, option) \
400  do { \
401  ret = set_expr(&hue->expr##_pexpr, &hue->expr##_expr, \
402  args, option, ctx); \
403  if (ret < 0) \
404  return ret; \
405  } while (0)
406 
407  if (!strcmp(cmd, "h")) {
408  SET_EXPR(hue_deg, "h");
409  av_freep(&hue->hue_expr);
410  } else if (!strcmp(cmd, "H")) {
411  SET_EXPR(hue, "H");
412  av_freep(&hue->hue_deg_expr);
413  } else if (!strcmp(cmd, "s")) {
414  SET_EXPR(saturation, "s");
415  } else if (!strcmp(cmd, "b")) {
416  SET_EXPR(brightness, "b");
417  } else
418  return AVERROR(ENOSYS);
419 
420  return 0;
421 }
422 
423 static const AVFilterPad hue_inputs[] = {
424  {
425  .name = "default",
426  .type = AVMEDIA_TYPE_VIDEO,
427  .filter_frame = filter_frame,
428  .config_props = config_props,
429  },
430  { NULL }
431 };
432 
433 static const AVFilterPad hue_outputs[] = {
434  {
435  .name = "default",
436  .type = AVMEDIA_TYPE_VIDEO,
437  },
438  { NULL }
439 };
440 
442  .name = "hue",
443  .description = NULL_IF_CONFIG_SMALL("Adjust the hue and saturation of the input video."),
444  .priv_size = sizeof(HueContext),
445  .init = init,
446  .uninit = uninit,
449  .inputs = hue_inputs,
450  .outputs = hue_outputs,
451  .priv_class = &hue_class,
453 };