FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
vf_colorbalance.c
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2013 Paul B Mahol
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 "libavutil/opt.h"
22 #include "libavutil/pixdesc.h"
23 #include "avfilter.h"
24 #include "drawutils.h"
25 #include "formats.h"
26 #include "internal.h"
27 #include "video.h"
28 
29 #define R 0
30 #define G 1
31 #define B 2
32 #define A 3
33 
34 typedef struct {
35  double shadows;
36  double midtones;
37  double highlights;
38 } Range;
39 
40 typedef struct {
41  const AVClass *class;
42  Range cyan_red;
43  Range magenta_green;
44  Range yellow_blue;
45 
46  uint8_t lut[3][256];
47 
48  uint8_t rgba_map[4];
49  int step;
50 } ColorBalanceContext;
51 
52 #define OFFSET(x) offsetof(ColorBalanceContext, x)
53 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
54 static const AVOption colorbalance_options[] = {
55  { "rs", "set red shadows", OFFSET(cyan_red.shadows), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1, 1, FLAGS },
56  { "gs", "set green shadows", OFFSET(magenta_green.shadows), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1, 1, FLAGS },
57  { "bs", "set blue shadows", OFFSET(yellow_blue.shadows), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1, 1, FLAGS },
58  { "rm", "set red midtones", OFFSET(cyan_red.midtones), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1, 1, FLAGS },
59  { "gm", "set green midtones", OFFSET(magenta_green.midtones), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1, 1, FLAGS },
60  { "bm", "set blue midtones", OFFSET(yellow_blue.midtones), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1, 1, FLAGS },
61  { "rh", "set red highlights", OFFSET(cyan_red.highlights), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1, 1, FLAGS },
62  { "gh", "set green highlights", OFFSET(magenta_green.highlights), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1, 1, FLAGS },
63  { "bh", "set blue highlights", OFFSET(yellow_blue.highlights), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1, 1, FLAGS },
64  { NULL }
65 };
66 
67 AVFILTER_DEFINE_CLASS(colorbalance);
68 
69 static int query_formats(AVFilterContext *ctx)
70 {
71  static const enum AVPixelFormat pix_fmts[] = {
72  AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
73  AV_PIX_FMT_RGBA, AV_PIX_FMT_BGRA,
74  AV_PIX_FMT_ABGR, AV_PIX_FMT_ARGB,
75  AV_PIX_FMT_0BGR, AV_PIX_FMT_0RGB,
76  AV_PIX_FMT_RGB0, AV_PIX_FMT_BGR0,
77  AV_PIX_FMT_NONE
78  };
79 
80  ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
81  return 0;
82 }
83 
84 static int config_output(AVFilterLink *outlink)
85 {
86  AVFilterContext *ctx = outlink->src;
87  ColorBalanceContext *cb = ctx->priv;
88  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(outlink->format);
89  double *shadows, *midtones, *highlights, *buffer;
90  int i, r, g, b;
91 
92  buffer = av_malloc(256 * 3 * sizeof(*buffer));
93  if (!buffer)
94  return AVERROR(ENOMEM);
95 
96  shadows = buffer + 256 * 0;
97  midtones = buffer + 256 * 1;
98  highlights = buffer + 256 * 2;
99 
100  for (i = 0; i < 256; i++) {
101  double low = av_clipd((i - 85.0) / -64.0 + 0.5, 0, 1) * 178.5;
102  double mid = av_clipd((i - 85.0) / 64.0 + 0.5, 0, 1) *
103  av_clipd((i + 85.0 - 255.0) / -64.0 + 0.5, 0, 1) * 178.5;
104 
105  shadows[i] = low;
106  midtones[i] = mid;
107  highlights[255 - i] = low;
108  }
109 
110  for (i = 0; i < 256; i++) {
111  r = g = b = i;
112 
113  r = av_clip_uint8(r + cb->cyan_red.shadows * shadows[r]);
114  r = av_clip_uint8(r + cb->cyan_red.midtones * midtones[r]);
115  r = av_clip_uint8(r + cb->cyan_red.highlights * highlights[r]);
116 
117  g = av_clip_uint8(g + cb->magenta_green.shadows * shadows[g]);
118  g = av_clip_uint8(g + cb->magenta_green.midtones * midtones[g]);
119  g = av_clip_uint8(g + cb->magenta_green.highlights * highlights[g]);
120 
121  b = av_clip_uint8(b + cb->yellow_blue.shadows * shadows[b]);
122  b = av_clip_uint8(b + cb->yellow_blue.midtones * midtones[b]);
123  b = av_clip_uint8(b + cb->yellow_blue.highlights * highlights[b]);
124 
125  cb->lut[R][i] = r;
126  cb->lut[G][i] = g;
127  cb->lut[B][i] = b;
128  }
129 
130  av_free(buffer);
131 
132  ff_fill_rgba_map(cb->rgba_map, outlink->format);
133  cb->step = av_get_padded_bits_per_pixel(desc) >> 3;
134 
135  return 0;
136 }
137 
138 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
139 {
140  AVFilterContext *ctx = inlink->dst;
141  ColorBalanceContext *cb = ctx->priv;
142  AVFilterLink *outlink = ctx->outputs[0];
143  const uint8_t roffset = cb->rgba_map[R];
144  const uint8_t goffset = cb->rgba_map[G];
145  const uint8_t boffset = cb->rgba_map[B];
146  const uint8_t aoffset = cb->rgba_map[A];
147  const int step = cb->step;
148  const uint8_t *srcrow = in->data[0];
149  uint8_t *dstrow;
150  AVFrame *out;
151  int i, j;
152 
153  if (av_frame_is_writable(in)) {
154  out = in;
155  } else {
156  out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
157  if (!out) {
158  av_frame_free(&in);
159  return AVERROR(ENOMEM);
160  }
161  av_frame_copy_props(out, in);
162  }
163 
164  dstrow = out->data[0];
165  for (i = 0; i < outlink->h; i++) {
166  const uint8_t *src = srcrow;
167  uint8_t *dst = dstrow;
168 
169  for (j = 0; j < outlink->w * step; j += step) {
170  dst[j + roffset] = cb->lut[R][src[j + roffset]];
171  dst[j + goffset] = cb->lut[G][src[j + goffset]];
172  dst[j + boffset] = cb->lut[B][src[j + boffset]];
173  if (in != out && step == 4)
174  dst[j + aoffset] = src[j + aoffset];
175  }
176 
177  srcrow += in->linesize[0];
178  dstrow += out->linesize[0];
179  }
180 
181  if (in != out)
182  av_frame_free(&in);
183  return ff_filter_frame(ctx->outputs[0], out);
184 }
185 
186 static const AVFilterPad colorbalance_inputs[] = {
187  {
188  .name = "default",
189  .type = AVMEDIA_TYPE_VIDEO,
190  .filter_frame = filter_frame,
191  },
192  { NULL }
193 };
194 
195 static const AVFilterPad colorbalance_outputs[] = {
196  {
197  .name = "default",
198  .type = AVMEDIA_TYPE_VIDEO,
199  .config_props = config_output,
200  },
201  { NULL }
202 };
203 
204 AVFilter ff_vf_colorbalance = {
205  .name = "colorbalance",
206  .description = NULL_IF_CONFIG_SMALL("Adjust the color balance."),
207  .priv_size = sizeof(ColorBalanceContext),
208  .priv_class = &colorbalance_class,
209  .query_formats = query_formats,
210  .inputs = colorbalance_inputs,
211  .outputs = colorbalance_outputs,
212  .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
213 };
Generated on Sun Mar 23 2014 23:50:08 for FFmpeg by   doxygen 1.8.2