/*
* Copyright (c) 2002 A'rpi
* 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
* border detection filter
* Ported from MPlayer libmpcodecs/vf_cropdetect.c.
*/
#include "libavutil/imgutils.h"
#include "libavutil/internal.h"
#include "libavutil/opt.h"
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
typedef struct CropDetectContext {
const AVClass *class;
int x1, y1, x2, y2;
float limit;
int round;
int reset_count;
int frame_nb;
int max_pixsteps[4];
int max_outliers;
} CropDetectContext;
static int query_formats(AVFilterContext *ctx)
{
static const enum AVPixelFormat pix_fmts[] = {
AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVJ420P,
AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUVJ422P,
AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVJ444P,
AV_PIX_FMT_YUV411P, AV_PIX_FMT_GRAY8,
AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV410P,
AV_PIX_FMT_YUV420P9 , AV_PIX_FMT_YUV422P9 , AV_PIX_FMT_YUV444P9,
AV_PIX_FMT_YUV420P10, AV_PIX_FMT_YUV422P10, AV_PIX_FMT_YUV444P10,
AV_PIX_FMT_YUV420P12, AV_PIX_FMT_YUV422P12, AV_PIX_FMT_YUV444P12,
AV_PIX_FMT_YUV420P14, AV_PIX_FMT_YUV422P14, AV_PIX_FMT_YUV444P14,
AV_PIX_FMT_YUV420P16, AV_PIX_FMT_YUV422P16, AV_PIX_FMT_YUV444P16,
AV_PIX_FMT_NV12, AV_PIX_FMT_NV21,
AV_PIX_FMT_RGB24, AV_PIX_FMT_BGR24,
AV_PIX_FMT_RGBA, AV_PIX_FMT_BGRA,
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);
}
static int checkline(void *ctx, const unsigned char *src, int stride, int len, int bpp)
{
int total = 0;
const uint16_t *src16 = (const uint16_t *)src;
switch (bpp) {
case 1:
while (len >= 8) {
total += src[ 0] + src[ stride] + src[2*stride] + src[3*stride]
+ src[4*stride] + src[5*stride] + src[6*stride] + src[7*stride];
src += 8*stride;
len -= 8;
}
while (--len >= 0) {
total += src[0];
src += stride;
}
break;
case 2:
stride >>= 1;
while (len >= 8) {
total += src16[ 0] + src16[ stride] + src16[2*stride] + src16[3*stride]
+ src16[4*stride] + src16[5*stride] + src16[6*stride] + src16[7*stride];
src16 += 8*stride;
len -= 8;
}
while (--len >= 0) {
total += src16[0];
src16 += stride;
}
break;
case 3:
case 4:
while (len >= 4) {
total += src[0] + src[1 ] + src[2 ]
+ src[ stride] + src[1+ stride] + src[2+ stride]
+ src[2*stride] + src[1+2*stride] + src[2+2*stride]
+ src[3*stride] + src[1+3*stride] + src[2+3*stride];
src += 4*stride;
len -= 4;
}
while (--len >= 0) {
total += src[0] + src[1] + src[2];
src += stride;
}
break;
}
av_log(ctx, AV_LOG_DEBUG, "total:%d\n", total);
return total;
}
static av_cold int init(AVFilterContext *ctx)
{
CropDetectContext *s = ctx->priv;
s->frame_nb = -2;
av_log(ctx, AV_LOG_VERBOSE, "limit:%f round:%d reset_count:%d\n",
s->limit, s->round, s->reset_count);
return 0;
}
static int config_input(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
CropDetectContext *s = ctx->priv;
const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
av_image_fill_max_pixsteps(s->max_pixsteps, NULL, desc);
if (s->limit < 1.0)
s->limit *= (1 << (desc->comp[0].depth_minus1 + 1)) - 1;
s->x1 = inlink->w - 1;
s->y1 = inlink->h - 1;
s->x2 = 0;
s->y2 = 0;
return 0;
}
#define SET_META(key, value) \
av_dict_set_int(metadata, key, value, 0)
static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
{
AVFilterContext *ctx = inlink->dst;
CropDetectContext *s = ctx->priv;
int bpp = s->max_pixsteps[0];
int w, h, x, y, shrink_by;
AVDictionary **metadata;
int outliers, last_y;
int limit = round(s->limit);
// ignore first 2 frames - they may be empty
if (++s->frame_nb > 0) {
metadata = avpriv_frame_get_metadatap(frame);
// Reset the crop area every reset_count frames, if reset_count is > 0
if (s->reset_count > 0 && s->frame_nb > s->reset_count) {
s->x1 = frame->width - 1;
s->y1 = frame->height - 1;
s->x2 = 0;
s->y2 = 0;
s->frame_nb = 1;
}
#define FIND(DST, FROM, NOEND, INC, STEP0, STEP1, LEN) \
outliers = 0;\
for (last_y = y = FROM; NOEND; y = y INC) {\
if (checkline(ctx, frame->data[0] + STEP0 * y, STEP1, LEN, bpp) > limit) {\
if (++outliers > s->max_outliers) { \
DST = last_y;\
break;\
}\
} else\
last_y = y INC;\
}
FIND(s->y1, 0, y < s->y1, +1, frame->linesize[0], bpp, frame->width);
FIND(s->y2, frame->height - 1, y > FFMAX(s->y2, s->y1), -1, frame->linesize[0], bpp, frame->width);
FIND(s->x1, 0, y < s->x1, +1, bpp, frame->linesize[0], frame->height);
FIND(s->x2, frame->width - 1, y > FFMAX(s->x2, s->x1), -1, bpp, frame->linesize[0], frame->height);
// round x and y (up), important for yuv colorspaces
// make sure they stay rounded!
x = (s->x1+1) & ~1;
y = (s->y1+1) & ~1;
w = s->x2 - x + 1;
h = s->y2 - y + 1;
// w and h must be divisible by 2 as well because of yuv
// colorspace problems.
if (s->round <= 1)
s->round = 16;
if (s->round % 2)
s->round *= 2;
shrink_by = w % s->round;
w -= shrink_by;
x += (shrink_by/2 + 1) & ~1;
shrink_by = h % s->round;
h -= shrink_by;
y += (shrink_by/2 + 1) & ~1;
SET_META("lavfi.cropdetect.x1", s->x1);
SET_META("lavfi.cropdetect.x2", s->x2);
SET_META("lavfi.cropdetect.y1", s->y1);
SET_META("lavfi.cropdetect.y2", s->y2);
SET_META("lavfi.cropdetect.w", w);
SET_META("lavfi.cropdetect.h", h);
SET_META("lavfi.cropdetect.x", x);
SET_META("lavfi.cropdetect.y", y);
av_log(ctx, AV_LOG_INFO,
"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",
s->x1, s->x2, s->y1, s->y2, w, h, x, y, frame->pts,
frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base),
w, h, x, y);
}
return ff_filter_frame(inlink->dst->outputs[0], frame);
}
#define OFFSET(x) offsetof(CropDetectContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
static const AVOption cropdetect_options[] = {
{ "limit", "Threshold below which the pixel is considered black", OFFSET(limit), AV_OPT_TYPE_FLOAT, { .dbl = 24.0/255 }, 0, 65535, FLAGS },
{ "round", "Value by which the width/height should be divisible", OFFSET(round), AV_OPT_TYPE_INT, { .i64 = 16 }, 0, INT_MAX, FLAGS },
{ "reset", "Recalculate the crop area after this many frames", OFFSET(reset_count), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
{ "reset_count", "Recalculate the crop area after this many frames",OFFSET(reset_count),AV_OPT_TYPE_INT,{ .i64 = 0 }, 0, INT_MAX, FLAGS },
{ "max_outliers", "Threshold count of outliers", OFFSET(max_outliers),AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(cropdetect);
static const AVFilterPad avfilter_vf_cropdetect_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_input,
.filter_frame = filter_frame,
},
{ NULL }
};
static const AVFilterPad avfilter_vf_cropdetect_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO
},
{ NULL }
};
AVFilter ff_vf_cropdetect = {
.name = "cropdetect",
.description = NULL_IF_CONFIG_SMALL("Auto-detect crop size."),
.priv_size = sizeof(CropDetectContext),
.priv_class = &cropdetect_class,
.init = init,
.query_formats = query_formats,
.inputs = avfilter_vf_cropdetect_inputs,
.outputs = avfilter_vf_cropdetect_outputs,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};