| /* |
| * 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 "avfilter.h" |
| #include "internal.h" |
| #include "formats.h" |
| #include "internal.h" |
| #include "video.h" |
| |
| typedef struct { |
| unsigned int bamount; ///< black amount |
| unsigned 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 |
| }; |
| |
| ff_set_common_formats(ctx, ff_make_format_list(pix_fmts)); |
| return 0; |
| } |
| |
| static av_cold int init(AVFilterContext *ctx, const char *args) |
| { |
| BlackFrameContext *blackframe = ctx->priv; |
| |
| blackframe->bamount = 98; |
| blackframe->bthresh = 32; |
| blackframe->nblack = 0; |
| blackframe->frame = 0; |
| blackframe->last_keyframe = 0; |
| |
| if (args) |
| sscanf(args, "%u:%u", &blackframe->bamount, &blackframe->bthresh); |
| |
| av_log(ctx, AV_LOG_VERBOSE, "bamount:%u bthresh:%u\n", |
| blackframe->bamount, blackframe->bthresh); |
| |
| if (blackframe->bamount > 100 || blackframe->bthresh > 255) { |
| av_log(ctx, AV_LOG_ERROR, "Too big value for bamount (max is 100) or bthresh (max is 255)\n"); |
| return AVERROR(EINVAL); |
| } |
| |
| return 0; |
| } |
| |
| static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *frame) |
| { |
| AVFilterContext *ctx = inlink->dst; |
| BlackFrameContext *blackframe = ctx->priv; |
| int x, i; |
| int pblack = 0; |
| uint8_t *p = frame->data[0]; |
| |
| for (i = 0; i < frame->video->h; i++) { |
| for (x = 0; x < inlink->w; x++) |
| blackframe->nblack += p[x] < blackframe->bthresh; |
| p += frame->linesize[0]; |
| } |
| |
| if (frame->video->key_frame) |
| blackframe->last_keyframe = blackframe->frame; |
| |
| pblack = blackframe->nblack * 100 / (inlink->w * inlink->h); |
| if (pblack >= blackframe->bamount) |
| av_log(ctx, AV_LOG_INFO, "frame:%u pblack:%u pos:%"PRId64" pts:%"PRId64" t:%f " |
| "type:%c last_keyframe:%d\n", |
| blackframe->frame, pblack, frame->pos, frame->pts, |
| frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base), |
| av_get_picture_type_char(frame->video->pict_type), blackframe->last_keyframe); |
| |
| blackframe->frame++; |
| blackframe->nblack = 0; |
| return ff_filter_frame(inlink->dst->outputs[0], frame); |
| } |
| |
| static const AVFilterPad avfilter_vf_blackframe_inputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, |
| .get_video_buffer = ff_null_get_video_buffer, |
| .filter_frame = filter_frame, |
| }, |
| { NULL } |
| }; |
| |
| static const AVFilterPad avfilter_vf_blackframe_outputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO |
| }, |
| { NULL } |
| }; |
| |
| AVFilter avfilter_vf_blackframe = { |
| .name = "blackframe", |
| .description = NULL_IF_CONFIG_SMALL("Detect frames that are (almost) black."), |
| |
| .priv_size = sizeof(BlackFrameContext), |
| .init = init, |
| |
| .query_formats = query_formats, |
| |
| .inputs = avfilter_vf_blackframe_inputs, |
| |
| .outputs = avfilter_vf_blackframe_outputs, |
| }; |