| 1 | /* |
| 2 | * Copyright (c) 2003 Rich Felker |
| 3 | * Copyright (c) 2012 Stefano Sabatini |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License as published by |
| 9 | * the Free Software Foundation; either version 2 of the License, or |
| 10 | * (at your option) any later version. |
| 11 | * |
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License along |
| 18 | * with FFmpeg; if not, write to the Free Software Foundation, Inc., |
| 19 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | */ |
| 21 | |
| 22 | /** |
| 23 | * @file mpdecimate filter, ported from libmpcodecs/vf_decimate.c by |
| 24 | * Rich Felker. |
| 25 | */ |
| 26 | |
| 27 | #include "libavutil/opt.h" |
| 28 | #include "libavutil/pixdesc.h" |
| 29 | #include "libavutil/pixelutils.h" |
| 30 | #include "libavutil/timestamp.h" |
| 31 | #include "avfilter.h" |
| 32 | #include "internal.h" |
| 33 | #include "formats.h" |
| 34 | #include "video.h" |
| 35 | |
| 36 | typedef struct { |
| 37 | const AVClass *class; |
| 38 | int lo, hi; ///< lower and higher threshold number of differences |
| 39 | ///< values for 8x8 blocks |
| 40 | |
| 41 | float frac; ///< threshold of changed pixels over the total fraction |
| 42 | |
| 43 | int max_drop_count; ///< if positive: maximum number of sequential frames to drop |
| 44 | ///< if negative: minimum number of frames between two drops |
| 45 | |
| 46 | int drop_count; ///< if positive: number of frames sequentially dropped |
| 47 | ///< if negative: number of sequential frames which were not dropped |
| 48 | |
| 49 | int hsub, vsub; ///< chroma subsampling values |
| 50 | AVFrame *ref; ///< reference picture |
| 51 | av_pixelutils_sad_fn sad; ///< sum of absolute difference function |
| 52 | } DecimateContext; |
| 53 | |
| 54 | #define OFFSET(x) offsetof(DecimateContext, x) |
| 55 | #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM |
| 56 | |
| 57 | static const AVOption mpdecimate_options[] = { |
| 58 | { "max", "set the maximum number of consecutive dropped frames (positive), or the minimum interval between dropped frames (negative)", |
| 59 | OFFSET(max_drop_count), AV_OPT_TYPE_INT, {.i64=0}, INT_MIN, INT_MAX, FLAGS }, |
| 60 | { "hi", "set high dropping threshold", OFFSET(hi), AV_OPT_TYPE_INT, {.i64=64*12}, INT_MIN, INT_MAX, FLAGS }, |
| 61 | { "lo", "set low dropping threshold", OFFSET(lo), AV_OPT_TYPE_INT, {.i64=64*5}, INT_MIN, INT_MAX, FLAGS }, |
| 62 | { "frac", "set fraction dropping threshold", OFFSET(frac), AV_OPT_TYPE_FLOAT, {.dbl=0.33}, 0, 1, FLAGS }, |
| 63 | { NULL } |
| 64 | }; |
| 65 | |
| 66 | AVFILTER_DEFINE_CLASS(mpdecimate); |
| 67 | |
| 68 | /** |
| 69 | * Return 1 if the two planes are different, 0 otherwise. |
| 70 | */ |
| 71 | static int diff_planes(AVFilterContext *ctx, |
| 72 | uint8_t *cur, int cur_linesize, |
| 73 | uint8_t *ref, int ref_linesize, |
| 74 | int w, int h) |
| 75 | { |
| 76 | DecimateContext *decimate = ctx->priv; |
| 77 | |
| 78 | int x, y; |
| 79 | int d, c = 0; |
| 80 | int t = (w/16)*(h/16)*decimate->frac; |
| 81 | |
| 82 | /* compute difference for blocks of 8x8 bytes */ |
| 83 | for (y = 0; y < h-7; y += 4) { |
| 84 | for (x = 8; x < w-7; x += 4) { |
| 85 | d = decimate->sad(cur + y*cur_linesize + x, cur_linesize, |
| 86 | ref + y*ref_linesize + x, ref_linesize); |
| 87 | if (d > decimate->hi) |
| 88 | return 1; |
| 89 | if (d > decimate->lo) { |
| 90 | c++; |
| 91 | if (c > t) |
| 92 | return 1; |
| 93 | } |
| 94 | } |
| 95 | } |
| 96 | return 0; |
| 97 | } |
| 98 | |
| 99 | /** |
| 100 | * Tell if the frame should be decimated, for example if it is no much |
| 101 | * different with respect to the reference frame ref. |
| 102 | */ |
| 103 | static int decimate_frame(AVFilterContext *ctx, |
| 104 | AVFrame *cur, AVFrame *ref) |
| 105 | { |
| 106 | DecimateContext *decimate = ctx->priv; |
| 107 | int plane; |
| 108 | |
| 109 | if (decimate->max_drop_count > 0 && |
| 110 | decimate->drop_count >= decimate->max_drop_count) |
| 111 | return 0; |
| 112 | if (decimate->max_drop_count < 0 && |
| 113 | (decimate->drop_count-1) > decimate->max_drop_count) |
| 114 | return 0; |
| 115 | |
| 116 | for (plane = 0; ref->data[plane] && ref->linesize[plane]; plane++) { |
| 117 | int vsub = plane == 1 || plane == 2 ? decimate->vsub : 0; |
| 118 | int hsub = plane == 1 || plane == 2 ? decimate->hsub : 0; |
| 119 | if (diff_planes(ctx, |
| 120 | cur->data[plane], cur->linesize[plane], |
| 121 | ref->data[plane], ref->linesize[plane], |
| 122 | FF_CEIL_RSHIFT(ref->width, hsub), |
| 123 | FF_CEIL_RSHIFT(ref->height, vsub))) |
| 124 | return 0; |
| 125 | } |
| 126 | |
| 127 | return 1; |
| 128 | } |
| 129 | |
| 130 | static av_cold int init(AVFilterContext *ctx) |
| 131 | { |
| 132 | DecimateContext *decimate = ctx->priv; |
| 133 | |
| 134 | decimate->sad = av_pixelutils_get_sad_fn(3, 3, 0, decimate); // 8x8, not aligned on blocksize |
| 135 | if (!decimate->sad) |
| 136 | return AVERROR(EINVAL); |
| 137 | |
| 138 | av_log(ctx, AV_LOG_VERBOSE, "max_drop_count:%d hi:%d lo:%d frac:%f\n", |
| 139 | decimate->max_drop_count, decimate->hi, decimate->lo, decimate->frac); |
| 140 | |
| 141 | return 0; |
| 142 | } |
| 143 | |
| 144 | static av_cold void uninit(AVFilterContext *ctx) |
| 145 | { |
| 146 | DecimateContext *decimate = ctx->priv; |
| 147 | av_frame_free(&decimate->ref); |
| 148 | } |
| 149 | |
| 150 | static int query_formats(AVFilterContext *ctx) |
| 151 | { |
| 152 | static const enum AVPixelFormat pix_fmts[] = { |
| 153 | AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P, |
| 154 | AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV411P, |
| 155 | AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV440P, |
| 156 | AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P, |
| 157 | AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ440P, |
| 158 | AV_PIX_FMT_YUVA420P, |
| 159 | AV_PIX_FMT_NONE |
| 160 | }; |
| 161 | |
| 162 | ff_set_common_formats(ctx, ff_make_format_list(pix_fmts)); |
| 163 | |
| 164 | return 0; |
| 165 | } |
| 166 | |
| 167 | static int config_input(AVFilterLink *inlink) |
| 168 | { |
| 169 | AVFilterContext *ctx = inlink->dst; |
| 170 | DecimateContext *decimate = ctx->priv; |
| 171 | const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format); |
| 172 | decimate->hsub = pix_desc->log2_chroma_w; |
| 173 | decimate->vsub = pix_desc->log2_chroma_h; |
| 174 | |
| 175 | return 0; |
| 176 | } |
| 177 | |
| 178 | static int filter_frame(AVFilterLink *inlink, AVFrame *cur) |
| 179 | { |
| 180 | DecimateContext *decimate = inlink->dst->priv; |
| 181 | AVFilterLink *outlink = inlink->dst->outputs[0]; |
| 182 | int ret; |
| 183 | |
| 184 | if (decimate->ref && decimate_frame(inlink->dst, cur, decimate->ref)) { |
| 185 | decimate->drop_count = FFMAX(1, decimate->drop_count+1); |
| 186 | } else { |
| 187 | av_frame_free(&decimate->ref); |
| 188 | decimate->ref = cur; |
| 189 | decimate->drop_count = FFMIN(-1, decimate->drop_count-1); |
| 190 | |
| 191 | if (ret = ff_filter_frame(outlink, av_frame_clone(cur)) < 0) |
| 192 | return ret; |
| 193 | } |
| 194 | |
| 195 | av_log(inlink->dst, AV_LOG_DEBUG, |
| 196 | "%s pts:%s pts_time:%s drop_count:%d\n", |
| 197 | decimate->drop_count > 0 ? "drop" : "keep", |
| 198 | av_ts2str(cur->pts), av_ts2timestr(cur->pts, &inlink->time_base), |
| 199 | decimate->drop_count); |
| 200 | |
| 201 | if (decimate->drop_count > 0) |
| 202 | av_frame_free(&cur); |
| 203 | |
| 204 | return 0; |
| 205 | } |
| 206 | |
| 207 | static int request_frame(AVFilterLink *outlink) |
| 208 | { |
| 209 | DecimateContext *decimate = outlink->src->priv; |
| 210 | AVFilterLink *inlink = outlink->src->inputs[0]; |
| 211 | int ret; |
| 212 | |
| 213 | do { |
| 214 | ret = ff_request_frame(inlink); |
| 215 | } while (decimate->drop_count > 0 && ret >= 0); |
| 216 | |
| 217 | return ret; |
| 218 | } |
| 219 | |
| 220 | static const AVFilterPad mpdecimate_inputs[] = { |
| 221 | { |
| 222 | .name = "default", |
| 223 | .type = AVMEDIA_TYPE_VIDEO, |
| 224 | .config_props = config_input, |
| 225 | .filter_frame = filter_frame, |
| 226 | }, |
| 227 | { NULL } |
| 228 | }; |
| 229 | |
| 230 | static const AVFilterPad mpdecimate_outputs[] = { |
| 231 | { |
| 232 | .name = "default", |
| 233 | .type = AVMEDIA_TYPE_VIDEO, |
| 234 | .request_frame = request_frame, |
| 235 | }, |
| 236 | { NULL } |
| 237 | }; |
| 238 | |
| 239 | AVFilter ff_vf_mpdecimate = { |
| 240 | .name = "mpdecimate", |
| 241 | .description = NULL_IF_CONFIG_SMALL("Remove near-duplicate frames."), |
| 242 | .init = init, |
| 243 | .uninit = uninit, |
| 244 | .priv_size = sizeof(DecimateContext), |
| 245 | .priv_class = &mpdecimate_class, |
| 246 | .query_formats = query_formats, |
| 247 | .inputs = mpdecimate_inputs, |
| 248 | .outputs = mpdecimate_outputs, |
| 249 | }; |