| 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 | int limit; |
| 39 | int round; |
| 40 | int reset_count; |
| 41 | int frame_nb; |
| 42 | int max_pixsteps[4]; |
| 43 | } CropDetectContext; |
| 44 | |
| 45 | static int query_formats(AVFilterContext *ctx) |
| 46 | { |
| 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, |
| 53 | AV_PIX_FMT_NONE |
| 54 | }; |
| 55 | |
| 56 | ff_set_common_formats(ctx, ff_make_format_list(pix_fmts)); |
| 57 | return 0; |
| 58 | } |
| 59 | |
| 60 | static int checkline(void *ctx, const unsigned char *src, int stride, int len, int bpp) |
| 61 | { |
| 62 | int total = 0; |
| 63 | int div = len; |
| 64 | |
| 65 | switch (bpp) { |
| 66 | case 1: |
| 67 | while (--len >= 0) { |
| 68 | total += src[0]; |
| 69 | src += stride; |
| 70 | } |
| 71 | break; |
| 72 | case 3: |
| 73 | case 4: |
| 74 | while (--len >= 0) { |
| 75 | total += src[0] + src[1] + src[2]; |
| 76 | src += stride; |
| 77 | } |
| 78 | div *= 3; |
| 79 | break; |
| 80 | } |
| 81 | total /= div; |
| 82 | |
| 83 | av_log(ctx, AV_LOG_DEBUG, "total:%d\n", total); |
| 84 | return total; |
| 85 | } |
| 86 | |
| 87 | static av_cold int init(AVFilterContext *ctx) |
| 88 | { |
| 89 | CropDetectContext *s = ctx->priv; |
| 90 | |
| 91 | s->frame_nb = -2; |
| 92 | |
| 93 | av_log(ctx, AV_LOG_VERBOSE, "limit:%d round:%d reset_count:%d\n", |
| 94 | s->limit, s->round, s->reset_count); |
| 95 | |
| 96 | return 0; |
| 97 | } |
| 98 | |
| 99 | static int config_input(AVFilterLink *inlink) |
| 100 | { |
| 101 | AVFilterContext *ctx = inlink->dst; |
| 102 | CropDetectContext *s = ctx->priv; |
| 103 | |
| 104 | av_image_fill_max_pixsteps(s->max_pixsteps, NULL, |
| 105 | av_pix_fmt_desc_get(inlink->format)); |
| 106 | |
| 107 | s->x1 = inlink->w - 1; |
| 108 | s->y1 = inlink->h - 1; |
| 109 | s->x2 = 0; |
| 110 | s->y2 = 0; |
| 111 | |
| 112 | return 0; |
| 113 | } |
| 114 | |
| 115 | #define SET_META(key, value) \ |
| 116 | av_dict_set_int(metadata, key, value, 0) |
| 117 | |
| 118 | static int filter_frame(AVFilterLink *inlink, AVFrame *frame) |
| 119 | { |
| 120 | AVFilterContext *ctx = inlink->dst; |
| 121 | CropDetectContext *s = ctx->priv; |
| 122 | int bpp = s->max_pixsteps[0]; |
| 123 | int w, h, x, y, shrink_by; |
| 124 | AVDictionary **metadata; |
| 125 | |
| 126 | // ignore first 2 frames - they may be empty |
| 127 | if (++s->frame_nb > 0) { |
| 128 | metadata = avpriv_frame_get_metadatap(frame); |
| 129 | |
| 130 | // Reset the crop area every reset_count frames, if reset_count is > 0 |
| 131 | if (s->reset_count > 0 && s->frame_nb > s->reset_count) { |
| 132 | s->x1 = frame->width - 1; |
| 133 | s->y1 = frame->height - 1; |
| 134 | s->x2 = 0; |
| 135 | s->y2 = 0; |
| 136 | s->frame_nb = 1; |
| 137 | } |
| 138 | |
| 139 | for (y = 0; y < s->y1; y++) { |
| 140 | if (checkline(ctx, frame->data[0] + frame->linesize[0] * y, bpp, frame->width, bpp) > s->limit) { |
| 141 | s->y1 = y; |
| 142 | break; |
| 143 | } |
| 144 | } |
| 145 | |
| 146 | for (y = frame->height - 1; y > FFMAX(s->y2, s->y1); y--) { |
| 147 | if (checkline(ctx, frame->data[0] + frame->linesize[0] * y, bpp, frame->width, bpp) > s->limit) { |
| 148 | s->y2 = y; |
| 149 | break; |
| 150 | } |
| 151 | } |
| 152 | |
| 153 | for (y = 0; y < s->x1; y++) { |
| 154 | if (checkline(ctx, frame->data[0] + bpp*y, frame->linesize[0], frame->height, bpp) > s->limit) { |
| 155 | s->x1 = y; |
| 156 | break; |
| 157 | } |
| 158 | } |
| 159 | |
| 160 | for (y = frame->width - 1; y > FFMAX(s->x2, s->x1); y--) { |
| 161 | if (checkline(ctx, frame->data[0] + bpp*y, frame->linesize[0], frame->height, bpp) > s->limit) { |
| 162 | s->x2 = y; |
| 163 | break; |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | // round x and y (up), important for yuv colorspaces |
| 168 | // make sure they stay rounded! |
| 169 | x = (s->x1+1) & ~1; |
| 170 | y = (s->y1+1) & ~1; |
| 171 | |
| 172 | w = s->x2 - x + 1; |
| 173 | h = s->y2 - y + 1; |
| 174 | |
| 175 | // w and h must be divisible by 2 as well because of yuv |
| 176 | // colorspace problems. |
| 177 | if (s->round <= 1) |
| 178 | s->round = 16; |
| 179 | if (s->round % 2) |
| 180 | s->round *= 2; |
| 181 | |
| 182 | shrink_by = w % s->round; |
| 183 | w -= shrink_by; |
| 184 | x += (shrink_by/2 + 1) & ~1; |
| 185 | |
| 186 | shrink_by = h % s->round; |
| 187 | h -= shrink_by; |
| 188 | y += (shrink_by/2 + 1) & ~1; |
| 189 | |
| 190 | SET_META("lavfi.cropdetect.x1", s->x1); |
| 191 | SET_META("lavfi.cropdetect.x2", s->x2); |
| 192 | SET_META("lavfi.cropdetect.y1", s->y1); |
| 193 | SET_META("lavfi.cropdetect.y2", s->y2); |
| 194 | SET_META("lavfi.cropdetect.w", w); |
| 195 | SET_META("lavfi.cropdetect.h", h); |
| 196 | SET_META("lavfi.cropdetect.x", x); |
| 197 | SET_META("lavfi.cropdetect.y", y); |
| 198 | |
| 199 | av_log(ctx, AV_LOG_INFO, |
| 200 | "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", |
| 201 | s->x1, s->x2, s->y1, s->y2, w, h, x, y, frame->pts, |
| 202 | frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base), |
| 203 | w, h, x, y); |
| 204 | } |
| 205 | |
| 206 | return ff_filter_frame(inlink->dst->outputs[0], frame); |
| 207 | } |
| 208 | |
| 209 | #define OFFSET(x) offsetof(CropDetectContext, x) |
| 210 | #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM |
| 211 | |
| 212 | static const AVOption cropdetect_options[] = { |
| 213 | { "limit", "Threshold below which the pixel is considered black", OFFSET(limit), AV_OPT_TYPE_INT, { .i64 = 24 }, 0, 255, FLAGS }, |
| 214 | { "round", "Value by which the width/height should be divisible", OFFSET(round), AV_OPT_TYPE_INT, { .i64 = 16 }, 0, INT_MAX, FLAGS }, |
| 215 | { "reset", "Recalculate the crop area after this many frames", OFFSET(reset_count), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS }, |
| 216 | { "reset_count", "Recalculate the crop area after this many frames",OFFSET(reset_count),AV_OPT_TYPE_INT,{ .i64 = 0 }, 0, INT_MAX, FLAGS }, |
| 217 | { NULL } |
| 218 | }; |
| 219 | |
| 220 | AVFILTER_DEFINE_CLASS(cropdetect); |
| 221 | |
| 222 | static const AVFilterPad avfilter_vf_cropdetect_inputs[] = { |
| 223 | { |
| 224 | .name = "default", |
| 225 | .type = AVMEDIA_TYPE_VIDEO, |
| 226 | .config_props = config_input, |
| 227 | .filter_frame = filter_frame, |
| 228 | }, |
| 229 | { NULL } |
| 230 | }; |
| 231 | |
| 232 | static const AVFilterPad avfilter_vf_cropdetect_outputs[] = { |
| 233 | { |
| 234 | .name = "default", |
| 235 | .type = AVMEDIA_TYPE_VIDEO |
| 236 | }, |
| 237 | { NULL } |
| 238 | }; |
| 239 | |
| 240 | AVFilter ff_vf_cropdetect = { |
| 241 | .name = "cropdetect", |
| 242 | .description = NULL_IF_CONFIG_SMALL("Auto-detect crop size."), |
| 243 | .priv_size = sizeof(CropDetectContext), |
| 244 | .priv_class = &cropdetect_class, |
| 245 | .init = init, |
| 246 | .query_formats = query_formats, |
| 247 | .inputs = avfilter_vf_cropdetect_inputs, |
| 248 | .outputs = avfilter_vf_cropdetect_outputs, |
| 249 | .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, |
| 250 | }; |