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vf_histogram.c
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1 /*
2  * Copyright (c) 2012-2013 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/avassert.h"
22 #include "libavutil/opt.h"
23 #include "libavutil/parseutils.h"
24 #include "libavutil/pixdesc.h"
25 #include "avfilter.h"
26 #include "formats.h"
27 #include "internal.h"
28 #include "video.h"
29 
36 };
37 
38 typedef struct HistogramContext {
39  const AVClass *class; ///< AVClass context for log and options purpose
41  unsigned histogram[256];
42  unsigned max_hval;
43  int ncomp;
44  const uint8_t *bg_color;
45  const uint8_t *fg_color;
48  int step;
52 
53 #define OFFSET(x) offsetof(HistogramContext, x)
54 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
55 
56 static const AVOption histogram_options[] = {
57  { "mode", "set histogram mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=MODE_LEVELS}, 0, MODE_NB-1, FLAGS, "mode"},
58  { "levels", "standard histogram", 0, AV_OPT_TYPE_CONST, {.i64=MODE_LEVELS}, 0, 0, FLAGS, "mode" },
59  { "waveform", "per row/column luminance graph", 0, AV_OPT_TYPE_CONST, {.i64=MODE_WAVEFORM}, 0, 0, FLAGS, "mode" },
60  { "color", "chroma values in vectorscope", 0, AV_OPT_TYPE_CONST, {.i64=MODE_COLOR}, 0, 0, FLAGS, "mode" },
61  { "color2", "chroma values in vectorscope", 0, AV_OPT_TYPE_CONST, {.i64=MODE_COLOR2}, 0, 0, FLAGS, "mode" },
62  { "level_height", "set level height", OFFSET(level_height), AV_OPT_TYPE_INT, {.i64=200}, 50, 2048, FLAGS},
63  { "scale_height", "set scale height", OFFSET(scale_height), AV_OPT_TYPE_INT, {.i64=12}, 0, 40, FLAGS},
64  { "step", "set waveform step value", OFFSET(step), AV_OPT_TYPE_INT, {.i64=10}, 1, 255, FLAGS},
65  { "waveform_mode", "set waveform mode", OFFSET(waveform_mode), AV_OPT_TYPE_INT, {.i64=0}, 0, 1, FLAGS, "waveform_mode"},
66  { "row", NULL, 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "waveform_mode" },
67  { "column", NULL, 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "waveform_mode" },
68  { "display_mode", "set display mode", OFFSET(display_mode), AV_OPT_TYPE_INT, {.i64=1}, 0, 1, FLAGS, "display_mode"},
69  { "parade", NULL, 0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "display_mode" },
70  { "overlay", NULL, 0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "display_mode" },
71  { NULL },
72 };
73 
74 AVFILTER_DEFINE_CLASS(histogram);
75 
76 static av_cold int init(AVFilterContext *ctx, const char *args)
77 {
78  HistogramContext *h = ctx->priv;
79  int ret;
80 
81  h->class = &histogram_class;
83 
84  if ((ret = (av_set_options_string(h, args, "=", ":"))) < 0)
85  return ret;
86 
87  return 0;
88 }
89 
90 static const enum AVPixelFormat color_pix_fmts[] = {
93 };
94 
95 static const enum AVPixelFormat levels_pix_fmts[] = {
98 };
99 
101 {
102  HistogramContext *h = ctx->priv;
103  const enum AVPixelFormat *pix_fmts;
104 
105  switch (h->mode) {
106  case MODE_WAVEFORM:
107  case MODE_LEVELS:
108  pix_fmts = levels_pix_fmts;
109  break;
110  case MODE_COLOR:
111  case MODE_COLOR2:
112  pix_fmts = color_pix_fmts;
113  break;
114  default:
115  av_assert0(0);
116  }
117 
119 
120  return 0;
121 }
122 
123 static const uint8_t black_yuva_color[4] = { 0, 127, 127, 255 };
124 static const uint8_t black_gbrp_color[4] = { 0, 0, 0, 255 };
125 static const uint8_t white_yuva_color[4] = { 255, 127, 127, 255 };
126 static const uint8_t white_gbrp_color[4] = { 255, 255, 255, 255 };
127 
128 static int config_input(AVFilterLink *inlink)
129 {
130  HistogramContext *h = inlink->dst->priv;
131  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
132 
133  h->ncomp = desc->nb_components;
134 
135  switch (inlink->format) {
136  case AV_PIX_FMT_GBRP:
139  break;
140  default:
143  }
144 
145  return 0;
146 }
147 
148 static int config_output(AVFilterLink *outlink)
149 {
150  AVFilterContext *ctx = outlink->src;
151  HistogramContext *h = ctx->priv;
152 
153  switch (h->mode) {
154  case MODE_LEVELS:
155  outlink->w = 256;
156  outlink->h = (h->level_height + h->scale_height) * FFMAX(h->ncomp * h->display_mode, 1);
157  break;
158  case MODE_WAVEFORM:
159  if (h->waveform_mode)
160  outlink->h = 256 * FFMAX(h->ncomp * h->display_mode, 1);
161  else
162  outlink->w = 256 * FFMAX(h->ncomp * h->display_mode, 1);
163  break;
164  case MODE_COLOR:
165  case MODE_COLOR2:
166  outlink->h = outlink->w = 256;
167  break;
168  default:
169  av_assert0(0);
170  }
171 
172  outlink->sample_aspect_ratio = (AVRational){1,1};
173 
174  return 0;
175 }
176 
178 {
179  HistogramContext *h = inlink->dst->priv;
180  AVFilterContext *ctx = inlink->dst;
181  AVFilterLink *outlink = ctx->outputs[0];
183  const uint8_t *src;
184  uint8_t *dst;
185  int i, j, k, l, ret;
186 
187  out = ff_get_video_buffer(outlink, AV_PERM_WRITE, outlink->w, outlink->h);
188  if (!out) {
190  return AVERROR(ENOMEM);
191  }
192 
193  out->pts = in->pts;
194  out->pos = in->pos;
195 
196  for (k = 0; k < h->ncomp; k++)
197  for (i = 0; i < outlink->h; i++)
198  memset(out->data[k] + i * out->linesize[k], h->bg_color[k], outlink->w);
199 
200  switch (h->mode) {
201  case MODE_LEVELS:
202  for (k = 0; k < h->ncomp; k++) {
203  int start = k * (h->level_height + h->scale_height) * h->display_mode;
204 
205  for (i = 0; i < in->video->h; i++) {
206  src = in->data[k] + i * in->linesize[k];
207  for (j = 0; j < in->video->w; j++)
208  h->histogram[src[j]]++;
209  }
210 
211  for (i = 0; i < 256; i++)
212  h->max_hval = FFMAX(h->max_hval, h->histogram[i]);
213 
214  for (i = 0; i < outlink->w; i++) {
215  int col_height = h->level_height - (float)h->histogram[i] / h->max_hval * h->level_height;
216 
217  for (j = h->level_height - 1; j >= col_height; j--) {
218  if (h->display_mode) {
219  for (l = 0; l < h->ncomp; l++)
220  out->data[l][(j + start) * out->linesize[l] + i] = h->fg_color[l];
221  } else {
222  out->data[k][(j + start) * out->linesize[k] + i] = 255;
223  }
224  }
225  for (j = h->level_height + h->scale_height - 1; j >= h->level_height; j--)
226  out->data[k][(j + start) * out->linesize[k] + i] = i;
227  }
228 
229  memset(h->histogram, 0, 256 * sizeof(unsigned));
230  h->max_hval = 0;
231  }
232  break;
233  case MODE_WAVEFORM:
234  if (h->waveform_mode) {
235  for (k = 0; k < h->ncomp; k++) {
236  int offset = k * 256 * h->display_mode;
237  for (i = 0; i < inlink->w; i++) {
238  for (j = 0; j < inlink->h; j++) {
239  int pos = (offset +
240  in->data[k][j * in->linesize[k] + i]) *
241  out->linesize[k] + i;
242  unsigned value = out->data[k][pos];
243  value = FFMIN(value + h->step, 255);
244  out->data[k][pos] = value;
245  }
246  }
247  }
248  } else {
249  for (k = 0; k < h->ncomp; k++) {
250  int offset = k * 256 * h->display_mode;
251  for (i = 0; i < inlink->h; i++) {
252  src = in ->data[k] + i * in ->linesize[k];
253  dst = out->data[k] + i * out->linesize[k];
254  for (j = 0; j < inlink->w; j++) {
255  int pos = src[j] + offset;
256  unsigned value = dst[pos];
257  value = FFMIN(value + h->step, 255);
258  dst[pos] = value;
259  }
260  }
261  }
262  }
263  break;
264  case MODE_COLOR:
265  for (i = 0; i < inlink->h; i++) {
266  int iw1 = i * in->linesize[1];
267  int iw2 = i * in->linesize[2];
268  for (j = 0; j < inlink->w; j++) {
269  int pos = in->data[1][iw1 + j] * out->linesize[0] + in->data[2][iw2 + j];
270  if (out->data[0][pos] < 255)
271  out->data[0][pos]++;
272  }
273  }
274  for (i = 0; i < 256; i++) {
275  dst = out->data[0] + i * out->linesize[0];
276  for (j = 0; j < 256; j++) {
277  if (!dst[j]) {
278  out->data[1][i * out->linesize[0] + j] = i;
279  out->data[2][i * out->linesize[0] + j] = j;
280  }
281  }
282  }
283  break;
284  case MODE_COLOR2:
285  for (i = 0; i < inlink->h; i++) {
286  int iw1 = i * in->linesize[1];
287  int iw2 = i * in->linesize[2];
288  for (j = 0; j < inlink->w; j++) {
289  int u = in->data[1][iw1 + j];
290  int v = in->data[2][iw2 + j];
291  int pos = u * out->linesize[0] + v;
292  if (!out->data[0][pos])
293  out->data[0][pos] = FFABS(128 - u) + FFABS(128 - v);
294  out->data[1][pos] = u;
295  out->data[2][pos] = v;
296  }
297  }
298  break;
299  default:
300  av_assert0(0);
301  }
302 
303  ret = ff_filter_frame(outlink, out);
305  if (ret < 0)
306  return ret;
307  return 0;
308 }
309 
310 static av_cold void uninit(AVFilterContext *ctx)
311 {
312  HistogramContext *h = ctx->priv;
313 
314  av_opt_free(h);
315 }
316 
317 static const AVFilterPad inputs[] = {
318  {
319  .name = "default",
320  .type = AVMEDIA_TYPE_VIDEO,
321  .filter_frame = filter_frame,
322  .config_props = config_input,
323  .min_perms = AV_PERM_READ,
324  },
325  { NULL }
326 };
327 
328 static const AVFilterPad outputs[] = {
329  {
330  .name = "default",
331  .type = AVMEDIA_TYPE_VIDEO,
332  .config_props = config_output,
333  },
334  { NULL }
335 };
336 
338  .name = "histogram",
339  .description = NULL_IF_CONFIG_SMALL("Compute and draw a histogram."),
340  .priv_size = sizeof(HistogramContext),
341  .init = init,
342  .uninit = uninit,
344  .inputs = inputs,
345  .outputs = outputs,
346  .priv_class = &histogram_class,
347 };