FFmpeg
 All Data Structures Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
vf_cropdetect.c
Go to the documentation of this file.
1 /*
2  * Copyright (c) 2002 A'rpi
3  * This file is part of FFmpeg.
4  *
5  * FFmpeg is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License as published by
7  * the Free Software Foundation; either version 2 of the License, or
8  * (at your option) any later version.
9  *
10  * FFmpeg is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License along
16  * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18  */
19 
20 /**
21  * @file
22  * border detection filter
23  * Ported from MPlayer libmpcodecs/vf_cropdetect.c.
24  */
25 
26 #include "libavutil/imgutils.h"
27 #include "libavutil/internal.h"
28 #include "libavutil/opt.h"
29 
30 #include "avfilter.h"
31 #include "formats.h"
32 #include "internal.h"
33 #include "video.h"
34 
35 typedef struct CropDetectContext {
36  const AVClass *class;
37  int x1, y1, x2, y2;
38  float limit;
39  int round;
41  int frame_nb;
42  int max_pixsteps[4];
45 
47 {
48  static const enum AVPixelFormat pix_fmts[] = {
63  };
64 
65  AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
66  if (!fmts_list)
67  return AVERROR(ENOMEM);
68  return ff_set_common_formats(ctx, fmts_list);
69 }
70 
71 static int checkline(void *ctx, const unsigned char *src, int stride, int len, int bpp)
72 {
73  int total = 0;
74  int div = len;
75  const uint16_t *src16 = (const uint16_t *)src;
76 
77  switch (bpp) {
78  case 1:
79  while (len >= 8) {
80  total += src[ 0] + src[ stride] + src[2*stride] + src[3*stride]
81  + src[4*stride] + src[5*stride] + src[6*stride] + src[7*stride];
82  src += 8*stride;
83  len -= 8;
84  }
85  while (--len >= 0) {
86  total += src[0];
87  src += stride;
88  }
89  break;
90  case 2:
91  stride >>= 1;
92  while (len >= 8) {
93  total += src16[ 0] + src16[ stride] + src16[2*stride] + src16[3*stride]
94  + src16[4*stride] + src16[5*stride] + src16[6*stride] + src16[7*stride];
95  src16 += 8*stride;
96  len -= 8;
97  }
98  while (--len >= 0) {
99  total += src16[0];
100  src16 += stride;
101  }
102  break;
103  case 3:
104  case 4:
105  while (len >= 4) {
106  total += src[0] + src[1 ] + src[2 ]
107  + src[ stride] + src[1+ stride] + src[2+ stride]
108  + src[2*stride] + src[1+2*stride] + src[2+2*stride]
109  + src[3*stride] + src[1+3*stride] + src[2+3*stride];
110  src += 4*stride;
111  len -= 4;
112  }
113  while (--len >= 0) {
114  total += src[0] + src[1] + src[2];
115  src += stride;
116  }
117  div *= 3;
118  break;
119  }
120  total /= div;
121 
122  av_log(ctx, AV_LOG_DEBUG, "total:%d\n", total);
123  return total;
124 }
125 
126 static av_cold int init(AVFilterContext *ctx)
127 {
128  CropDetectContext *s = ctx->priv;
129 
130  s->frame_nb = -2;
131 
132  av_log(ctx, AV_LOG_VERBOSE, "limit:%f round:%d reset_count:%d\n",
133  s->limit, s->round, s->reset_count);
134 
135  return 0;
136 }
137 
138 static int config_input(AVFilterLink *inlink)
139 {
140  AVFilterContext *ctx = inlink->dst;
141  CropDetectContext *s = ctx->priv;
142  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
143 
145 
146  if (s->limit < 1.0)
147  s->limit *= (1 << (desc->comp[0].depth_minus1 + 1)) - 1;
148 
149  s->x1 = inlink->w - 1;
150  s->y1 = inlink->h - 1;
151  s->x2 = 0;
152  s->y2 = 0;
153 
154  return 0;
155 }
156 
157 #define SET_META(key, value) \
158  av_dict_set_int(metadata, key, value, 0)
159 
160 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
161 {
162  AVFilterContext *ctx = inlink->dst;
163  CropDetectContext *s = ctx->priv;
164  int bpp = s->max_pixsteps[0];
165  int w, h, x, y, shrink_by;
166  AVDictionary **metadata;
167  int outliers, last_y;
168  int limit = round(s->limit);
169 
170  // ignore first 2 frames - they may be empty
171  if (++s->frame_nb > 0) {
172  metadata = avpriv_frame_get_metadatap(frame);
173 
174  // Reset the crop area every reset_count frames, if reset_count is > 0
175  if (s->reset_count > 0 && s->frame_nb > s->reset_count) {
176  s->x1 = frame->width - 1;
177  s->y1 = frame->height - 1;
178  s->x2 = 0;
179  s->y2 = 0;
180  s->frame_nb = 1;
181  }
182 
183 #define FIND(DST, FROM, NOEND, INC, STEP0, STEP1, LEN) \
184  outliers = 0;\
185  for (last_y = y = FROM; NOEND; y = y INC) {\
186  if (checkline(ctx, frame->data[0] + STEP0 * y, STEP1, LEN, bpp) > limit) {\
187  if (++outliers > s->max_outliers) { \
188  DST = last_y;\
189  break;\
190  }\
191  } else\
192  last_y = y INC;\
193  }
194 
195  FIND(s->y1, 0, y < s->y1, +1, frame->linesize[0], bpp, frame->width);
196  FIND(s->y2, frame->height - 1, y > FFMAX(s->y2, s->y1), -1, frame->linesize[0], bpp, frame->width);
197  FIND(s->x1, 0, y < s->x1, +1, bpp, frame->linesize[0], frame->height);
198  FIND(s->x2, frame->width - 1, y > FFMAX(s->x2, s->x1), -1, bpp, frame->linesize[0], frame->height);
199 
200 
201  // round x and y (up), important for yuv colorspaces
202  // make sure they stay rounded!
203  x = (s->x1+1) & ~1;
204  y = (s->y1+1) & ~1;
205 
206  w = s->x2 - x + 1;
207  h = s->y2 - y + 1;
208 
209  // w and h must be divisible by 2 as well because of yuv
210  // colorspace problems.
211  if (s->round <= 1)
212  s->round = 16;
213  if (s->round % 2)
214  s->round *= 2;
215 
216  shrink_by = w % s->round;
217  w -= shrink_by;
218  x += (shrink_by/2 + 1) & ~1;
219 
220  shrink_by = h % s->round;
221  h -= shrink_by;
222  y += (shrink_by/2 + 1) & ~1;
223 
224  SET_META("lavfi.cropdetect.x1", s->x1);
225  SET_META("lavfi.cropdetect.x2", s->x2);
226  SET_META("lavfi.cropdetect.y1", s->y1);
227  SET_META("lavfi.cropdetect.y2", s->y2);
228  SET_META("lavfi.cropdetect.w", w);
229  SET_META("lavfi.cropdetect.h", h);
230  SET_META("lavfi.cropdetect.x", x);
231  SET_META("lavfi.cropdetect.y", y);
232 
233  av_log(ctx, AV_LOG_INFO,
234  "x1:%d x2:%d y1:%d y2:%d w:%d h:%d x:%d y:%d pts:%"PRId64" t:%f crop=%d:%d:%d:%d\n",
235  s->x1, s->x2, s->y1, s->y2, w, h, x, y, frame->pts,
236  frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base),
237  w, h, x, y);
238  }
239 
240  return ff_filter_frame(inlink->dst->outputs[0], frame);
241 }
242 
243 #define OFFSET(x) offsetof(CropDetectContext, x)
244 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
245 
246 static const AVOption cropdetect_options[] = {
247  { "limit", "Threshold below which the pixel is considered black", OFFSET(limit), AV_OPT_TYPE_FLOAT, { .dbl = 24.0/255 }, 0, 65535, FLAGS },
248  { "round", "Value by which the width/height should be divisible", OFFSET(round), AV_OPT_TYPE_INT, { .i64 = 16 }, 0, INT_MAX, FLAGS },
249  { "reset", "Recalculate the crop area after this many frames", OFFSET(reset_count), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
250  { "reset_count", "Recalculate the crop area after this many frames",OFFSET(reset_count),AV_OPT_TYPE_INT,{ .i64 = 0 }, 0, INT_MAX, FLAGS },
251  { "max_outliers", "Threshold count of outliers", OFFSET(max_outliers),AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
252  { NULL }
253 };
254 
255 AVFILTER_DEFINE_CLASS(cropdetect);
256 
258  {
259  .name = "default",
260  .type = AVMEDIA_TYPE_VIDEO,
261  .config_props = config_input,
262  .filter_frame = filter_frame,
263  },
264  { NULL }
265 };
266 
268  {
269  .name = "default",
270  .type = AVMEDIA_TYPE_VIDEO
271  },
272  { NULL }
273 };
274 
276  .name = "cropdetect",
277  .description = NULL_IF_CONFIG_SMALL("Auto-detect crop size."),
278  .priv_size = sizeof(CropDetectContext),
279  .priv_class = &cropdetect_class,
280  .init = init,
282  .inputs = avfilter_vf_cropdetect_inputs,
283  .outputs = avfilter_vf_cropdetect_outputs,
285 };
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:631
const AVPixFmtDescriptor * av_pix_fmt_desc_get(enum AVPixelFormat pix_fmt)
Definition: pixdesc.c:2129
This structure describes decoded (raw) audio or video data.
Definition: frame.h:171
AVOption.
Definition: opt.h:255
#define AV_PIX_FMT_YUV444P14
Definition: pixfmt.h:390
planar YUV 4:4:4, 24bpp, (1 Cr & Cb sample per 1x1 Y samples)
Definition: pixfmt.h:68
misc image utilities
static const AVFilterPad outputs[]
Definition: af_ashowinfo.c:248
Main libavfilter public API header.
packed RGB 8:8:8, 24bpp, RGBRGB...
Definition: pixfmt.h:65
#define SET_META(key, value)
#define AV_PIX_FMT_YUV420P12
Definition: pixfmt.h:384
AVFilterFormats * ff_make_format_list(const int *fmts)
Create a list of supported formats.
Definition: formats.c:283
AVFilter ff_vf_cropdetect
void av_image_fill_max_pixsteps(int max_pixsteps[4], int max_pixstep_comps[4], const AVPixFmtDescriptor *pixdesc)
Compute the max pixel step for each plane of an image with a format described by pixdesc.
Definition: imgutils.c:34
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
Definition: avfilter.h:451
const char * name
Pad name.
Definition: internal.h:69
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1158
AVComponentDescriptor comp[4]
Parameters that describe how pixels are packed.
Definition: pixdesc.h:100
#define av_cold
Definition: attributes.h:74
AVOptions.
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:257
static av_cold int init(AVFilterContext *ctx)
static AVFrame * frame
static double av_q2d(AVRational a)
Convert rational to double.
Definition: rational.h:80
planar YUV 4:2:2, 16bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV422P and setting col...
Definition: pixfmt.h:76
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
#define AV_PIX_FMT_YUV444P16
Definition: pixfmt.h:393
#define AV_PIX_FMT_YUV422P12
Definition: pixfmt.h:385
#define av_log(a,...)
A filter pad used for either input or output.
Definition: internal.h:63
static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
uint16_t depth_minus1
Number of bits in the component minus 1.
Definition: pixdesc.h:57
int width
width and height of the video frame
Definition: frame.h:220
int ff_set_common_formats(AVFilterContext *ctx, AVFilterFormats *formats)
A helper for query_formats() which sets all links to the same list of formats.
Definition: formats.c:542
#define FIND(DST, FROM, NOEND, INC, STEP0, STEP1, LEN)
#define AVERROR(e)
Definition: error.h:43
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:175
packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
Definition: pixfmt.h:97
void * priv
private data for use by the filter
Definition: avfilter.h:654
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
planar YUV 4:2:0, 12bpp, 1 plane for Y and 1 plane for the UV components, which are interleaved (firs...
Definition: pixfmt.h:91
static av_always_inline av_const double round(double x)
Definition: libm.h:162
#define AV_PIX_FMT_YUV444P10
Definition: pixfmt.h:383
#define FFMAX(a, b)
Definition: common.h:79
packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
Definition: pixfmt.h:95
planar YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
Definition: pixfmt.h:67
common internal API header
#define AV_PIX_FMT_YUV422P9
Definition: pixfmt.h:378
as above, but U and V bytes are swapped
Definition: pixfmt.h:92
float y
planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV420P and setting col...
Definition: pixfmt.h:75
static const AVOption cropdetect_options[]
packed RGB 8:8:8, 24bpp, BGRBGR...
Definition: pixfmt.h:66
#define AV_PIX_FMT_YUV444P9
Definition: pixfmt.h:379
AVFILTER_DEFINE_CLASS(cropdetect)
static int query_formats(AVFilterContext *ctx)
Definition: vf_cropdetect.c:46
#define AV_PIX_FMT_YUV420P16
Definition: pixfmt.h:391
static const AVFilterPad avfilter_vf_cropdetect_inputs[]
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
#define AV_PIX_FMT_YUV420P14
Definition: pixfmt.h:388
AVS_Value src
Definition: avisynth_c.h:482
AVDictionary ** avpriv_frame_get_metadatap(AVFrame *frame)
Definition: frame.c:47
int linesize[AV_NUM_DATA_POINTERS]
For video, size in bytes of each picture line.
Definition: frame.h:199
Descriptor that unambiguously describes how the bits of a pixel are stored in the up to 4 data planes...
Definition: pixdesc.h:69
#define FLAGS
#define AV_PIX_FMT_YUV420P10
Definition: pixfmt.h:380
planar YUV 4:1:0, 9bpp, (1 Cr & Cb sample per 4x4 Y samples)
Definition: pixfmt.h:69
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:470
static const AVFilterPad inputs[]
Definition: af_ashowinfo.c:239
const char * name
Filter name.
Definition: avfilter.h:474
#define AV_PIX_FMT_YUV420P9
Definition: pixfmt.h:377
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:648
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:209
#define AV_PIX_FMT_YUV422P14
Definition: pixfmt.h:389
#define AV_PIX_FMT_YUV422P10
Definition: pixfmt.h:381
static int flags
Definition: cpu.c:47
#define AV_PIX_FMT_YUV444P12
Definition: pixfmt.h:387
GLint GLenum GLboolean GLsizei stride
Definition: opengl_enc.c:105
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:63
Y , 8bpp.
Definition: pixfmt.h:71
planar YUV 4:4:4, 24bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV444P and setting col...
Definition: pixfmt.h:77
planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
Definition: pixfmt.h:70
static const AVFilterPad avfilter_vf_cropdetect_outputs[]
#define OFFSET(x)
int len
static int config_input(AVFilterLink *inlink)
A list of supported formats for one end of a filter link.
Definition: formats.h:64
An instance of a filter.
Definition: avfilter.h:633
int height
Definition: frame.h:220
planar YUV 4:4:0 (1 Cr & Cb sample per 1x2 Y samples)
Definition: pixfmt.h:101
#define stride
internal API functions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:61
#define AV_PIX_FMT_YUV422P16
Definition: pixfmt.h:392
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:240
static int checkline(void *ctx, const unsigned char *src, int stride, int len, int bpp)
Definition: vf_cropdetect.c:71