| /* |
| * Copyright (c) 2010 Stefano Sabatini |
| * Copyright (c) 2006 Ivo van Poorten |
| * Copyright (c) 2006 Julian Hall |
| * Copyright (c) 2002-2003 Brian J. Murrell |
| * |
| * 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 |
| * Search for black frames to detect scene transitions. |
| * Ported from MPlayer libmpcodecs/vf_blackframe.c. |
| */ |
| |
| #include <stdio.h> |
| #include <inttypes.h> |
| |
| #include "libavutil/internal.h" |
| #include "libavutil/opt.h" |
| #include "avfilter.h" |
| #include "formats.h" |
| #include "internal.h" |
| #include "video.h" |
| |
| typedef struct BlackFrameContext { |
| const AVClass *class; |
| int bamount; ///< black amount |
| int bthresh; ///< black threshold |
| unsigned int frame; ///< frame number |
| unsigned int nblack; ///< number of black pixels counted so far |
| unsigned int last_keyframe; ///< frame number of the last received key-frame |
| } BlackFrameContext; |
| |
| static int query_formats(AVFilterContext *ctx) |
| { |
| static const enum AVPixelFormat pix_fmts[] = { |
| AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV420P, AV_PIX_FMT_GRAY8, AV_PIX_FMT_NV12, |
| AV_PIX_FMT_NV21, AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV411P, |
| AV_PIX_FMT_NONE |
| }; |
| |
| AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts); |
| if (!fmts_list) |
| return AVERROR(ENOMEM); |
| return ff_set_common_formats(ctx, fmts_list); |
| } |
| |
| #define SET_META(key, format, value) \ |
| snprintf(buf, sizeof(buf), format, value); \ |
| av_dict_set(metadata, key, buf, 0) |
| |
| static int filter_frame(AVFilterLink *inlink, AVFrame *frame) |
| { |
| AVFilterContext *ctx = inlink->dst; |
| BlackFrameContext *s = ctx->priv; |
| int x, i; |
| int pblack = 0; |
| uint8_t *p = frame->data[0]; |
| AVDictionary **metadata; |
| char buf[32]; |
| |
| for (i = 0; i < frame->height; i++) { |
| for (x = 0; x < inlink->w; x++) |
| s->nblack += p[x] < s->bthresh; |
| p += frame->linesize[0]; |
| } |
| |
| if (frame->key_frame) |
| s->last_keyframe = s->frame; |
| |
| pblack = s->nblack * 100 / (inlink->w * inlink->h); |
| if (pblack >= s->bamount) { |
| metadata = avpriv_frame_get_metadatap(frame); |
| |
| av_log(ctx, AV_LOG_INFO, "frame:%u pblack:%u pts:%"PRId64" t:%f " |
| "type:%c last_keyframe:%d\n", |
| s->frame, pblack, frame->pts, |
| frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base), |
| av_get_picture_type_char(frame->pict_type), s->last_keyframe); |
| |
| SET_META("lavfi.blackframe.pblack", "%u", pblack); |
| } |
| |
| s->frame++; |
| s->nblack = 0; |
| return ff_filter_frame(inlink->dst->outputs[0], frame); |
| } |
| |
| #define OFFSET(x) offsetof(BlackFrameContext, x) |
| #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM |
| static const AVOption blackframe_options[] = { |
| { "amount", "Percentage of the pixels that have to be below the threshold " |
| "for the frame to be considered black.", OFFSET(bamount), AV_OPT_TYPE_INT, { .i64 = 98 }, 0, 100, FLAGS }, |
| { "threshold", "threshold below which a pixel value is considered black", |
| OFFSET(bthresh), AV_OPT_TYPE_INT, { .i64 = 32 }, 0, 255, FLAGS }, |
| { "thresh", "threshold below which a pixel value is considered black", |
| OFFSET(bthresh), AV_OPT_TYPE_INT, { .i64 = 32 }, 0, 255, FLAGS }, |
| { NULL } |
| }; |
| |
| AVFILTER_DEFINE_CLASS(blackframe); |
| |
| static const AVFilterPad avfilter_vf_blackframe_inputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, |
| .filter_frame = filter_frame, |
| }, |
| { NULL } |
| }; |
| |
| static const AVFilterPad avfilter_vf_blackframe_outputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO |
| }, |
| { NULL } |
| }; |
| |
| AVFilter ff_vf_blackframe = { |
| .name = "blackframe", |
| .description = NULL_IF_CONFIG_SMALL("Detect frames that are (almost) black."), |
| .priv_size = sizeof(BlackFrameContext), |
| .priv_class = &blackframe_class, |
| .query_formats = query_formats, |
| .inputs = avfilter_vf_blackframe_inputs, |
| .outputs = avfilter_vf_blackframe_outputs, |
| }; |