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;
40 int skip;
41 int reset_count;
42 int frame_nb;
43 int max_pixsteps[4];
44 int max_outliers;
45 } CropDetectContext;
46
query_formats(AVFilterContext * ctx)47 static int query_formats(AVFilterContext *ctx)
48 {
49 static const enum AVPixelFormat pix_fmts[] = {
50 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVJ420P,
51 AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUVJ422P,
52 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVJ444P,
53 AV_PIX_FMT_YUV411P, AV_PIX_FMT_GRAY8,
54 AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV410P,
55 AV_PIX_FMT_YUV420P9 , AV_PIX_FMT_YUV422P9 , AV_PIX_FMT_YUV444P9,
56 AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV444P10,
57 AV_PIX_FMT_YUV420P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV444P12,
58 AV_PIX_FMT_YUV420P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV444P14,
59 AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
60 AV_PIX_FMT_NV12, AV_PIX_FMT_NV21,
61 AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
62 AV_PIX_FMT_RGBA, AV_PIX_FMT_BGRA,
63 AV_PIX_FMT_NONE
64 };
65
66 AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
67 if (!fmts_list)
68 return AVERROR(ENOMEM);
69 return ff_set_common_formats(ctx, fmts_list);
70 }
71
checkline(void * ctx,const unsigned char * src,int stride,int len,int bpp)72 static int checkline(void *ctx, const unsigned char *src, int stride, int len, int bpp)
73 {
74 int total = 0;
75 int div = len;
76 const uint16_t *src16 = (const uint16_t *)src;
77
78 switch (bpp) {
79 case 1:
80 while (len >= 8) {
81 total += src[ 0] + src[ stride] + src[2*stride] + src[3*stride]
82 + src[4*stride] + src[5*stride] + src[6*stride] + src[7*stride];
83 src += 8*stride;
84 len -= 8;
85 }
86 while (--len >= 0) {
87 total += src[0];
88 src += stride;
89 }
90 break;
91 case 2:
92 stride >>= 1;
93 while (len >= 8) {
94 total += src16[ 0] + src16[ stride] + src16[2*stride] + src16[3*stride]
95 + src16[4*stride] + src16[5*stride] + src16[6*stride] + src16[7*stride];
96 src16 += 8*stride;
97 len -= 8;
98 }
99 while (--len >= 0) {
100 total += src16[0];
101 src16 += stride;
102 }
103 break;
104 case 3:
105 case 4:
106 while (len >= 4) {
107 total += src[0] + src[1 ] + src[2 ]
108 + src[ stride] + src[1+ stride] + src[2+ stride]
109 + src[2*stride] + src[1+2*stride] + src[2+2*stride]
110 + src[3*stride] + src[1+3*stride] + src[2+3*stride];
111 src += 4*stride;
112 len -= 4;
113 }
114 while (--len >= 0) {
115 total += src[0] + src[1] + src[2];
116 src += stride;
117 }
118 div *= 3;
119 break;
120 }
121 total /= div;
122
123 av_log(ctx, AV_LOG_DEBUG, "total:%d\n", total);
124 return total;
125 }
126
init(AVFilterContext * ctx)127 static av_cold int init(AVFilterContext *ctx)
128 {
129 CropDetectContext *s = ctx->priv;
130
131 s->frame_nb = -1 * s->skip;
132
133 av_log(ctx, AV_LOG_VERBOSE, "limit:%f round:%d skip:%d reset_count:%d\n",
134 s->limit, s->round, s->skip, s->reset_count);
135
136 return 0;
137 }
138
config_input(AVFilterLink * inlink)139 static int config_input(AVFilterLink *inlink)
140 {
141 AVFilterContext *ctx = inlink->dst;
142 CropDetectContext *s = ctx->priv;
143 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
144
145 av_image_fill_max_pixsteps(s->max_pixsteps, NULL, desc);
146
147 if (s->limit < 1.0)
148 s->limit *= (1 << desc->comp[0].depth) - 1;
149
150 s->x1 = inlink->w - 1;
151 s->y1 = inlink->h - 1;
152 s->x2 = 0;
153 s->y2 = 0;
154
155 return 0;
156 }
157
158 #define SET_META(key, value) \
159 av_dict_set_int(metadata, key, value, 0)
160
filter_frame(AVFilterLink * inlink,AVFrame * frame)161 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
162 {
163 AVFilterContext *ctx = inlink->dst;
164 CropDetectContext *s = ctx->priv;
165 int bpp = s->max_pixsteps[0];
166 int w, h, x, y, shrink_by;
167 AVDictionary **metadata;
168 int outliers, last_y;
169 int limit = lrint(s->limit);
170
171 // ignore first s->skip frames
172 if (++s->frame_nb > 0) {
173 metadata = &frame->metadata;
174
175 // Reset the crop area every reset_count frames, if reset_count is > 0
176 if (s->reset_count > 0 && s->frame_nb > s->reset_count) {
177 s->x1 = frame->width - 1;
178 s->y1 = frame->height - 1;
179 s->x2 = 0;
180 s->y2 = 0;
181 s->frame_nb = 1;
182 }
183
184 #define FIND(DST, FROM, NOEND, INC, STEP0, STEP1, LEN) \
185 outliers = 0;\
186 for (last_y = y = FROM; NOEND; y = y INC) {\
187 if (checkline(ctx, frame->data[0] + STEP0 * y, STEP1, LEN, bpp) > limit) {\
188 if (++outliers > s->max_outliers) { \
189 DST = last_y;\
190 break;\
191 }\
192 } else\
193 last_y = y INC;\
194 }
195
196 FIND(s->y1, 0, y < s->y1, +1, frame->linesize[0], bpp, frame->width);
197 FIND(s->y2, frame->height - 1, y > FFMAX(s->y2, s->y1), -1, frame->linesize[0], bpp, frame->width);
198 FIND(s->x1, 0, y < s->x1, +1, bpp, frame->linesize[0], frame->height);
199 FIND(s->x2, frame->width - 1, y > FFMAX(s->x2, s->x1), -1, bpp, frame->linesize[0], frame->height);
200
201
202 // round x and y (up), important for yuv colorspaces
203 // make sure they stay rounded!
204 x = (s->x1+1) & ~1;
205 y = (s->y1+1) & ~1;
206
207 w = s->x2 - x + 1;
208 h = s->y2 - y + 1;
209
210 // w and h must be divisible by 2 as well because of yuv
211 // colorspace problems.
212 if (s->round <= 1)
213 s->round = 16;
214 if (s->round % 2)
215 s->round *= 2;
216
217 shrink_by = w % s->round;
218 w -= shrink_by;
219 x += (shrink_by/2 + 1) & ~1;
220
221 shrink_by = h % s->round;
222 h -= shrink_by;
223 y += (shrink_by/2 + 1) & ~1;
224
225 SET_META("lavfi.cropdetect.x1", s->x1);
226 SET_META("lavfi.cropdetect.x2", s->x2);
227 SET_META("lavfi.cropdetect.y1", s->y1);
228 SET_META("lavfi.cropdetect.y2", s->y2);
229 SET_META("lavfi.cropdetect.w", w);
230 SET_META("lavfi.cropdetect.h", h);
231 SET_META("lavfi.cropdetect.x", x);
232 SET_META("lavfi.cropdetect.y", y);
233
234 av_log(ctx, AV_LOG_INFO,
235 "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",
236 s->x1, s->x2, s->y1, s->y2, w, h, x, y, frame->pts,
237 frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base),
238 w, h, x, y);
239 }
240
241 return ff_filter_frame(inlink->dst->outputs[0], frame);
242 }
243
244 #define OFFSET(x) offsetof(CropDetectContext, x)
245 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
246
247 static const AVOption cropdetect_options[] = {
248 { "limit", "Threshold below which the pixel is considered black", OFFSET(limit), AV_OPT_TYPE_FLOAT, { .dbl = 24.0/255 }, 0, 65535, FLAGS },
249 { "round", "Value by which the width/height should be divisible", OFFSET(round), AV_OPT_TYPE_INT, { .i64 = 16 }, 0, INT_MAX, FLAGS },
250 { "reset", "Recalculate the crop area after this many frames", OFFSET(reset_count), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
251 { "skip", "Number of initial frames to skip", OFFSET(skip), AV_OPT_TYPE_INT, { .i64 = 2 }, 0, INT_MAX, FLAGS },
252 { "reset_count", "Recalculate the crop area after this many frames",OFFSET(reset_count),AV_OPT_TYPE_INT,{ .i64 = 0 }, 0, INT_MAX, FLAGS },
253 { "max_outliers", "Threshold count of outliers", OFFSET(max_outliers),AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
254 { NULL }
255 };
256
257 AVFILTER_DEFINE_CLASS(cropdetect);
258
259 static const AVFilterPad avfilter_vf_cropdetect_inputs[] = {
260 {
261 .name = "default",
262 .type = AVMEDIA_TYPE_VIDEO,
263 .config_props = config_input,
264 .filter_frame = filter_frame,
265 },
266 { NULL }
267 };
268
269 static const AVFilterPad avfilter_vf_cropdetect_outputs[] = {
270 {
271 .name = "default",
272 .type = AVMEDIA_TYPE_VIDEO
273 },
274 { NULL }
275 };
276
277 AVFilter ff_vf_cropdetect = {
278 .name = "cropdetect",
279 .description = NULL_IF_CONFIG_SMALL("Auto-detect crop size."),
280 .priv_size = sizeof(CropDetectContext),
281 .priv_class = &cropdetect_class,
282 .init = init,
283 .query_formats = query_formats,
284 .inputs = avfilter_vf_cropdetect_inputs,
285 .outputs = avfilter_vf_cropdetect_outputs,
286 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
287 };
288