2 * Copyright (c) 2002 A'rpi
3 * This file is part of FFmpeg.
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.
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.
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.
22 * border detection filter
23 * Ported from MPlayer libmpcodecs/vf_cropdetect.c.
26 #include "libavutil/imgutils.h"
27 #include "libavutil/internal.h"
28 #include "libavutil/opt.h"
45 static int query_formats(AVFilterContext *ctx)
47 static const enum AVPixelFormat pix_fmts[] = {
48 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVJ420P,
49 AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUVJ422P,
50 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVJ444P,
51 AV_PIX_FMT_YUV411P, AV_PIX_FMT_GRAY8,
52 AV_PIX_FMT_NV12, AV_PIX_FMT_NV21,
56 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
60 static int checkline(void *ctx, const unsigned char *src, int stride, int len, int bpp)
75 total += src[0] + src[1] + src[2];
83 av_log(ctx, AV_LOG_DEBUG, "total:%d\n", total);
87 static av_cold int init(AVFilterContext *ctx)
89 CropDetectContext *s = ctx->priv;
93 av_log(ctx, AV_LOG_VERBOSE, "limit:%d round:%d reset_count:%d\n",
94 s->limit, s->round, s->reset_count);
99 static int config_input(AVFilterLink *inlink)
101 AVFilterContext *ctx = inlink->dst;
102 CropDetectContext *s = ctx->priv;
104 av_image_fill_max_pixsteps(s->max_pixsteps, NULL,
105 av_pix_fmt_desc_get(inlink->format));
107 s->x1 = inlink->w - 1;
108 s->y1 = inlink->h - 1;
115 #define SET_META(key, value) \
116 snprintf(buf, sizeof(buf), "%d", value); \
117 av_dict_set(metadata, key, buf, 0)
119 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
121 AVFilterContext *ctx = inlink->dst;
122 CropDetectContext *s = ctx->priv;
123 int bpp = s->max_pixsteps[0];
124 int w, h, x, y, shrink_by;
125 AVDictionary **metadata;
128 // ignore first 2 frames - they may be empty
129 if (++s->frame_nb > 0) {
130 metadata = avpriv_frame_get_metadatap(frame);
132 // Reset the crop area every reset_count frames, if reset_count is > 0
133 if (s->reset_count > 0 && s->frame_nb > s->reset_count) {
134 s->x1 = frame->width - 1;
135 s->y1 = frame->height - 1;
141 for (y = 0; y < s->y1; y++) {
142 if (checkline(ctx, frame->data[0] + frame->linesize[0] * y, bpp, frame->width, bpp) > s->limit) {
148 for (y = frame->height - 1; y > s->y2; y--) {
149 if (checkline(ctx, frame->data[0] + frame->linesize[0] * y, bpp, frame->width, bpp) > s->limit) {
155 for (y = 0; y < s->x1; y++) {
156 if (checkline(ctx, frame->data[0] + bpp*y, frame->linesize[0], frame->height, bpp) > s->limit) {
162 for (y = frame->width - 1; y > s->x2; y--) {
163 if (checkline(ctx, frame->data[0] + bpp*y, frame->linesize[0], frame->height, bpp) > s->limit) {
169 // round x and y (up), important for yuv colorspaces
170 // make sure they stay rounded!
177 // w and h must be divisible by 2 as well because of yuv
178 // colorspace problems.
184 shrink_by = w % s->round;
186 x += (shrink_by/2 + 1) & ~1;
188 shrink_by = h % s->round;
190 y += (shrink_by/2 + 1) & ~1;
192 SET_META("lavfi.cropdetect.x1", s->x1);
193 SET_META("lavfi.cropdetect.x2", s->x2);
194 SET_META("lavfi.cropdetect.y1", s->y1);
195 SET_META("lavfi.cropdetect.y2", s->y2);
196 SET_META("lavfi.cropdetect.w", w);
197 SET_META("lavfi.cropdetect.h", h);
198 SET_META("lavfi.cropdetect.x", x);
199 SET_META("lavfi.cropdetect.y", y);
201 av_log(ctx, AV_LOG_INFO,
202 "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",
203 s->x1, s->x2, s->y1, s->y2, w, h, x, y, frame->pts,
204 frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base),
208 return ff_filter_frame(inlink->dst->outputs[0], frame);
211 #define OFFSET(x) offsetof(CropDetectContext, x)
212 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
214 static const AVOption cropdetect_options[] = {
215 { "limit", "Threshold below which the pixel is considered black", OFFSET(limit), AV_OPT_TYPE_INT, { .i64 = 24 }, 0, 255, FLAGS },
216 { "round", "Value by which the width/height should be divisible", OFFSET(round), AV_OPT_TYPE_INT, { .i64 = 16 }, 0, INT_MAX, FLAGS },
217 { "reset", "Recalculate the crop area after this many frames", OFFSET(reset_count), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
218 { "reset_count", "Recalculate the crop area after this many frames",OFFSET(reset_count),AV_OPT_TYPE_INT,{ .i64 = 0 }, 0, INT_MAX, FLAGS },
222 AVFILTER_DEFINE_CLASS(cropdetect);
224 static const AVFilterPad avfilter_vf_cropdetect_inputs[] = {
227 .type = AVMEDIA_TYPE_VIDEO,
228 .config_props = config_input,
229 .filter_frame = filter_frame,
234 static const AVFilterPad avfilter_vf_cropdetect_outputs[] = {
237 .type = AVMEDIA_TYPE_VIDEO
242 AVFilter ff_vf_cropdetect = {
243 .name = "cropdetect",
244 .description = NULL_IF_CONFIG_SMALL("Auto-detect crop size."),
245 .priv_size = sizeof(CropDetectContext),
246 .priv_class = &cropdetect_class,
248 .query_formats = query_formats,
249 .inputs = avfilter_vf_cropdetect_inputs,
250 .outputs = avfilter_vf_cropdetect_outputs,
251 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,