| /* |
| * Copyright (c) 2003 Rich Felker |
| * Copyright (c) 2012 Stefano Sabatini |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with FFmpeg; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| */ |
| |
| /** |
| * @file decimate filter, ported from libmpcodecs/vf_decimate.c by |
| * Rich Felker. |
| */ |
| |
| #include "libavutil/pixdesc.h" |
| #include "libavutil/timestamp.h" |
| #include "libavcodec/dsputil.h" |
| #include "avfilter.h" |
| #include "internal.h" |
| #include "formats.h" |
| #include "video.h" |
| |
| typedef struct { |
| int lo, hi; ///< lower and higher threshold number of differences |
| ///< values for 8x8 blocks |
| |
| float frac; ///< threshold of changed pixels over the total fraction |
| |
| int max_drop_count; ///< if positive: maximum number of sequential frames to drop |
| ///< if negative: minimum number of frames between two drops |
| |
| int drop_count; ///< if positive: number of frames sequentially dropped |
| ///< if negative: number of sequential frames which were not dropped |
| |
| int hsub, vsub; ///< chroma subsampling values |
| AVFilterBufferRef *ref; ///< reference picture |
| DSPContext dspctx; ///< context providing optimized diff routines |
| AVCodecContext *avctx; ///< codec context required for the DSPContext |
| } DecimateContext; |
| |
| /** |
| * Return 1 if the two planes are different, 0 otherwise. |
| */ |
| static int diff_planes(AVFilterContext *ctx, |
| uint8_t *cur, uint8_t *ref, int linesize, |
| int w, int h) |
| { |
| DecimateContext *decimate = ctx->priv; |
| DSPContext *dspctx = &decimate->dspctx; |
| |
| int x, y; |
| int d, c = 0; |
| int t = (w/16)*(h/16)*decimate->frac; |
| DCTELEM block[8*8]; |
| |
| /* compute difference for blocks of 8x8 bytes */ |
| for (y = 0; y < h-7; y += 4) { |
| for (x = 8; x < w-7; x += 4) { |
| dspctx->diff_pixels(block, |
| cur+x+y*linesize, |
| ref+x+y*linesize, linesize); |
| d = dspctx->sum_abs_dctelem(block); |
| if (d > decimate->hi) |
| return 1; |
| if (d > decimate->lo) { |
| c++; |
| if (c > t) |
| return 1; |
| } |
| } |
| } |
| return 0; |
| } |
| |
| /** |
| * Tell if the frame should be decimated, for example if it is no much |
| * different with respect to the reference frame ref. |
| */ |
| static int decimate_frame(AVFilterContext *ctx, |
| AVFilterBufferRef *cur, AVFilterBufferRef *ref) |
| { |
| DecimateContext *decimate = ctx->priv; |
| int plane; |
| |
| if (decimate->max_drop_count > 0 && |
| decimate->drop_count >= decimate->max_drop_count) |
| return 0; |
| if (decimate->max_drop_count < 0 && |
| (decimate->drop_count-1) > decimate->max_drop_count) |
| return 0; |
| |
| for (plane = 0; ref->data[plane] && ref->linesize[plane]; plane++) { |
| int vsub = plane == 1 || plane == 2 ? decimate->vsub : 0; |
| int hsub = plane == 1 || plane == 2 ? decimate->hsub : 0; |
| if (diff_planes(ctx, |
| cur->data[plane], ref->data[plane], ref->linesize[plane], |
| ref->video->w>>hsub, ref->video->h>>vsub)) |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| static av_cold int init(AVFilterContext *ctx, const char *args) |
| { |
| DecimateContext *decimate = ctx->priv; |
| |
| /* set default values */ |
| decimate->drop_count = decimate->max_drop_count = 0; |
| decimate->lo = 64*5; |
| decimate->hi = 64*12; |
| decimate->frac = 0.33; |
| |
| if (args) { |
| char c1, c2, c3, c4; |
| int n = sscanf(args, "%d%c%d%c%d%c%f%c", |
| &decimate->max_drop_count, &c1, |
| &decimate->hi, &c2, &decimate->lo, &c3, |
| &decimate->frac, &c4); |
| if (n != 1 && |
| (n != 3 || c1 != ':') && |
| (n != 5 || c1 != ':' || c2 != ':') && |
| (n != 7 || c1 != ':' || c2 != ':' || c3 != ':')) { |
| av_log(ctx, AV_LOG_ERROR, |
| "Invalid syntax for argument '%s': " |
| "must be in the form 'max:hi:lo:frac'\n", args); |
| return AVERROR(EINVAL); |
| } |
| } |
| |
| av_log(ctx, AV_LOG_VERBOSE, "max_drop_count:%d hi:%d lo:%d frac:%f\n", |
| decimate->max_drop_count, decimate->hi, decimate->lo, decimate->frac); |
| |
| decimate->avctx = avcodec_alloc_context3(NULL); |
| if (!decimate->avctx) |
| return AVERROR(ENOMEM); |
| dsputil_init(&decimate->dspctx, decimate->avctx); |
| |
| return 0; |
| } |
| |
| static av_cold void uninit(AVFilterContext *ctx) |
| { |
| DecimateContext *decimate = ctx->priv; |
| avfilter_unref_bufferp(&decimate->ref); |
| avcodec_close(decimate->avctx); |
| av_freep(&decimate->avctx); |
| } |
| |
| static int query_formats(AVFilterContext *ctx) |
| { |
| static const enum AVPixelFormat pix_fmts[] = { |
| AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P, |
| AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV411P, |
| AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV440P, |
| AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P, |
| AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ440P, |
| AV_PIX_FMT_YUVA420P, |
| AV_PIX_FMT_NONE |
| }; |
| |
| ff_set_common_formats(ctx, ff_make_format_list(pix_fmts)); |
| |
| return 0; |
| } |
| |
| static int config_input(AVFilterLink *inlink) |
| { |
| AVFilterContext *ctx = inlink->dst; |
| DecimateContext *decimate = ctx->priv; |
| const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format); |
| decimate->hsub = pix_desc->log2_chroma_w; |
| decimate->vsub = pix_desc->log2_chroma_h; |
| |
| return 0; |
| } |
| |
| static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *cur) |
| { |
| DecimateContext *decimate = inlink->dst->priv; |
| AVFilterLink *outlink = inlink->dst->outputs[0]; |
| int ret; |
| |
| if (decimate->ref && decimate_frame(inlink->dst, cur, decimate->ref)) { |
| decimate->drop_count = FFMAX(1, decimate->drop_count+1); |
| } else { |
| avfilter_unref_buffer(decimate->ref); |
| decimate->ref = cur; |
| decimate->drop_count = FFMIN(-1, decimate->drop_count-1); |
| |
| if (ret = ff_filter_frame(outlink, avfilter_ref_buffer(cur, ~AV_PERM_WRITE)) < 0) |
| return ret; |
| } |
| |
| av_log(inlink->dst, AV_LOG_DEBUG, |
| "%s pts:%s pts_time:%s drop_count:%d\n", |
| decimate->drop_count > 0 ? "drop" : "keep", |
| av_ts2str(cur->pts), av_ts2timestr(cur->pts, &inlink->time_base), |
| decimate->drop_count); |
| |
| if (decimate->drop_count > 0) |
| avfilter_unref_buffer(cur); |
| |
| return 0; |
| } |
| |
| static int request_frame(AVFilterLink *outlink) |
| { |
| DecimateContext *decimate = outlink->src->priv; |
| AVFilterLink *inlink = outlink->src->inputs[0]; |
| int ret; |
| |
| do { |
| ret = ff_request_frame(inlink); |
| } while (decimate->drop_count > 0 && ret >= 0); |
| |
| return ret; |
| } |
| |
| static const AVFilterPad decimate_inputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, |
| .get_video_buffer = ff_null_get_video_buffer, |
| .config_props = config_input, |
| .filter_frame = filter_frame, |
| .min_perms = AV_PERM_READ | AV_PERM_PRESERVE, |
| }, |
| { NULL } |
| }; |
| |
| static const AVFilterPad decimate_outputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, |
| .request_frame = request_frame, |
| }, |
| { NULL } |
| }; |
| |
| AVFilter avfilter_vf_decimate = { |
| .name = "decimate", |
| .description = NULL_IF_CONFIG_SMALL("Remove near-duplicate frames."), |
| .init = init, |
| .uninit = uninit, |
| |
| .priv_size = sizeof(DecimateContext), |
| .query_formats = query_formats, |
| .inputs = decimate_inputs, |
| .outputs = decimate_outputs, |
| }; |
