/*
* Copyright (c) 2008 vmrsss
* Copyright (c) 2009 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 Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser 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
* video padding filter
*/
#include "avfilter.h"
#include "formats.h"
#include "internal.h"
#include "video.h"
#include "libavutil/avstring.h"
#include "libavutil/common.h"
#include "libavutil/eval.h"
#include "libavutil/pixdesc.h"
#include "libavutil/colorspace.h"
#include "libavutil/avassert.h"
#include "libavutil/imgutils.h"
#include "libavutil/parseutils.h"
#include "libavutil/mathematics.h"
#include "libavutil/opt.h"
#include "drawutils.h"
static const char *const var_names[] = {
"in_w", "iw",
"in_h", "ih",
"out_w", "ow",
"out_h", "oh",
"x",
"y",
"a",
"sar",
"dar",
"hsub",
"vsub",
NULL
};
enum var_name {
VAR_IN_W, VAR_IW,
VAR_IN_H, VAR_IH,
VAR_OUT_W, VAR_OW,
VAR_OUT_H, VAR_OH,
VAR_X,
VAR_Y,
VAR_A,
VAR_SAR,
VAR_DAR,
VAR_HSUB,
VAR_VSUB,
VARS_NB
};
static int query_formats(AVFilterContext *ctx)
{
return ff_set_common_formats(ctx, ff_draw_supported_pixel_formats(0));
}
typedef struct PadContext {
const AVClass *class;
int w, h; ///< output dimensions, a value of 0 will result in the input size
int x, y; ///< offsets of the input area with respect to the padded area
int in_w, in_h; ///< width and height for the padded input video, which has to be aligned to the chroma values in order to avoid chroma issues
char *w_expr; ///< width expression string
char *h_expr; ///< height expression string
char *x_expr; ///< width expression string
char *y_expr; ///< height expression string
uint8_t rgba_color[4]; ///< color for the padding area
FFDrawContext draw;
FFDrawColor color;
} PadContext;
static int config_input(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
PadContext *s = ctx->priv;
int ret;
double var_values[VARS_NB], res;
char *expr;
ff_draw_init(&s->draw, inlink->format, 0);
ff_draw_color(&s->draw, &s->color, s->rgba_color);
var_values[VAR_IN_W] = var_values[VAR_IW] = inlink->w;
var_values[VAR_IN_H] = var_values[VAR_IH] = inlink->h;
var_values[VAR_OUT_W] = var_values[VAR_OW] = NAN;
var_values[VAR_OUT_H] = var_values[VAR_OH] = NAN;
var_values[VAR_A] = (double) inlink->w / inlink->h;
var_values[VAR_SAR] = inlink->sample_aspect_ratio.num ?
(double) inlink->sample_aspect_ratio.num / inlink->sample_aspect_ratio.den : 1;
var_values[VAR_DAR] = var_values[VAR_A] * var_values[VAR_SAR];
var_values[VAR_HSUB] = 1 << s->draw.hsub_max;
var_values[VAR_VSUB] = 1 << s->draw.vsub_max;
/* evaluate width and height */
av_expr_parse_and_eval(&res, (expr = s->w_expr),
var_names, var_values,
NULL, NULL, NULL, NULL, NULL, 0, ctx);
s->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
if ((ret = av_expr_parse_and_eval(&res, (expr = s->h_expr),
var_names, var_values,
NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
goto eval_fail;
s->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = res;
/* evaluate the width again, as it may depend on the evaluated output height */
if ((ret = av_expr_parse_and_eval(&res, (expr = s->w_expr),
var_names, var_values,
NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
goto eval_fail;
s->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
/* evaluate x and y */
av_expr_parse_and_eval(&res, (expr = s->x_expr),
var_names, var_values,
NULL, NULL, NULL, NULL, NULL, 0, ctx);
s->x = var_values[VAR_X] = res;
if ((ret = av_expr_parse_and_eval(&res, (expr = s->y_expr),
var_names, var_values,
NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
goto eval_fail;
s->y = var_values[VAR_Y] = res;
/* evaluate x again, as it may depend on the evaluated y value */
if ((ret = av_expr_parse_and_eval(&res, (expr = s->x_expr),
var_names, var_values,
NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
goto eval_fail;
s->x = var_values[VAR_X] = res;
/* sanity check params */
if (s->w < 0 || s->h < 0 || s->x < 0 || s->y < 0) {
av_log(ctx, AV_LOG_ERROR, "Negative values are not acceptable.\n");
return AVERROR(EINVAL);
}
if (!s->w)
s->w = inlink->w;
if (!s->h)
s->h = inlink->h;
s->w = ff_draw_round_to_sub(&s->draw, 0, -1, s->w);
s->h = ff_draw_round_to_sub(&s->draw, 1, -1, s->h);
s->x = ff_draw_round_to_sub(&s->draw, 0, -1, s->x);
s->y = ff_draw_round_to_sub(&s->draw, 1, -1, s->y);
s->in_w = ff_draw_round_to_sub(&s->draw, 0, -1, inlink->w);
s->in_h = ff_draw_round_to_sub(&s->draw, 1, -1, inlink->h);
av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d -> w:%d h:%d x:%d y:%d color:0x%02X%02X%02X%02X\n",
inlink->w, inlink->h, s->w, s->h, s->x, s->y,
s->rgba_color[0], s->rgba_color[1], s->rgba_color[2], s->rgba_color[3]);
if (s->x < 0 || s->y < 0 ||
s->w <= 0 || s->h <= 0 ||
(unsigned)s->x + (unsigned)inlink->w > s->w ||
(unsigned)s->y + (unsigned)inlink->h > s->h) {
av_log(ctx, AV_LOG_ERROR,
"Input area %d:%d:%d:%d not within the padded area 0:0:%d:%d or zero-sized\n",
s->x, s->y, s->x + inlink->w, s->y + inlink->h, s->w, s->h);
return AVERROR(EINVAL);
}
return 0;
eval_fail:
av_log(NULL, AV_LOG_ERROR,
"Error when evaluating the expression '%s'\n", expr);
return ret;
}
static int config_output(AVFilterLink *outlink)
{
PadContext *s = outlink->src->priv;
outlink->w = s->w;
outlink->h = s->h;
return 0;
}
static AVFrame *get_video_buffer(AVFilterLink *inlink, int w, int h)
{
PadContext *s = inlink->dst->priv;
AVFrame *frame = ff_get_video_buffer(inlink->dst->outputs[0],
w + (s->w - s->in_w),
h + (s->h - s->in_h));
int plane;
if (!frame)
return NULL;
frame->width = w;
frame->height = h;
for (plane = 0; plane < 4 && frame->data[plane] && frame->linesize[plane]; plane++) {
int hsub = s->draw.hsub[plane];
int vsub = s->draw.vsub[plane];
frame->data[plane] += (s->x >> hsub) * s->draw.pixelstep[plane] +
(s->y >> vsub) * frame->linesize[plane];
}
return frame;
}
/* check whether each plane in this buffer can be padded without copying */
static int buffer_needs_copy(PadContext *s, AVFrame *frame, AVBufferRef *buf)
{
int planes[4] = { -1, -1, -1, -1}, *p = planes;
int i, j;
/* get all planes in this buffer */
for (i = 0; i < FF_ARRAY_ELEMS(planes) && frame->data[i]; i++) {
if (av_frame_get_plane_buffer(frame, i) == buf)
*p++ = i;
}
/* for each plane in this buffer, check that it can be padded without
* going over buffer bounds or other planes */
for (i = 0; i < FF_ARRAY_ELEMS(planes) && planes[i] >= 0; i++) {
int hsub = s->draw.hsub[planes[i]];
int vsub = s->draw.vsub[planes[i]];
uint8_t *start = frame->data[planes[i]];
uint8_t *end = start + (frame->height >> vsub) *
frame->linesize[planes[i]];
/* amount of free space needed before the start and after the end
* of the plane */
ptrdiff_t req_start = (s->x >> hsub) * s->draw.pixelstep[planes[i]] +
(s->y >> vsub) * frame->linesize[planes[i]];
ptrdiff_t req_end = ((s->w - s->x - frame->width) >> hsub) *
s->draw.pixelstep[planes[i]] +
((s->h - s->y - frame->height) >> vsub) * frame->linesize[planes[i]];
if (frame->linesize[planes[i]] < (s->w >> hsub) * s->draw.pixelstep[planes[i]])
return 1;
if (start - buf->data < req_start ||
(buf->data + buf->size) - end < req_end)
return 1;
for (j = 0; j < FF_ARRAY_ELEMS(planes) && planes[j] >= 0; j++) {
int vsub1 = s->draw.vsub[planes[j]];
uint8_t *start1 = frame->data[planes[j]];
uint8_t *end1 = start1 + (frame->height >> vsub1) *
frame->linesize[planes[j]];
if (i == j)
continue;
if (FFSIGN(start - end1) != FFSIGN(start - end1 - req_start) ||
FFSIGN(end - start1) != FFSIGN(end - start1 + req_end))
return 1;
}
}
return 0;
}
static int frame_needs_copy(PadContext *s, AVFrame *frame)
{
int i;
if (!av_frame_is_writable(frame))
return 1;
for (i = 0; i < 4 && frame->buf[i]; i++)
if (buffer_needs_copy(s, frame, frame->buf[i]))
return 1;
return 0;
}
static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
PadContext *s = inlink->dst->priv;
AVFrame *out;
int needs_copy = frame_needs_copy(s, in);
if (needs_copy) {
av_log(inlink->dst, AV_LOG_DEBUG, "Direct padding impossible allocating new frame\n");
out = ff_get_video_buffer(inlink->dst->outputs[0],
FFMAX(inlink->w, s->w),
FFMAX(inlink->h, s->h));
if (!out) {
av_frame_free(&in);
return AVERROR(ENOMEM);
}
av_frame_copy_props(out, in);
} else {
int i;
out = in;
for (i = 0; i < 4 && out->data[i] && out->linesize[i]; i++) {
int hsub = s->draw.hsub[i];
int vsub = s->draw.vsub[i];
out->data[i] -= (s->x >> hsub) * s->draw.pixelstep[i] +
(s->y >> vsub) * out->linesize[i];
}
}
/* top bar */
if (s->y) {
ff_fill_rectangle(&s->draw, &s->color,
out->data, out->linesize,
0, 0, s->w, s->y);
}
/* bottom bar */
if (s->h > s->y + s->in_h) {
ff_fill_rectangle(&s->draw, &s->color,
out->data, out->linesize,
0, s->y + s->in_h, s->w, s->h - s->y - s->in_h);
}
/* left border */
ff_fill_rectangle(&s->draw, &s->color, out->data, out->linesize,
0, s->y, s->x, in->height);
if (needs_copy) {
ff_copy_rectangle2(&s->draw,
out->data, out->linesize, in->data, in->linesize,
s->x, s->y, 0, 0, in->width, in->height);
}
/* right border */
ff_fill_rectangle(&s->draw, &s->color, out->data, out->linesize,
s->x + s->in_w, s->y, s->w - s->x - s->in_w,
in->height);
out->width = s->w;
out->height = s->h;
if (in != out)
av_frame_free(&in);
return ff_filter_frame(inlink->dst->outputs[0], out);
}
#define OFFSET(x) offsetof(PadContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
static const AVOption pad_options[] = {
{ "width", "set the pad area width expression", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "w", "set the pad area width expression", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "height", "set the pad area height expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "h", "set the pad area height expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "x", "set the x offset expression for the input image position", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str = "0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "y", "set the y offset expression for the input image position", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str = "0"}, CHAR_MIN, CHAR_MAX, FLAGS },
{ "color", "set the color of the padded area border", OFFSET(rgba_color), AV_OPT_TYPE_COLOR, {.str = "black"}, .flags = FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(pad);
static const AVFilterPad avfilter_vf_pad_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_input,
.get_video_buffer = get_video_buffer,
.filter_frame = filter_frame,
},
{ NULL }
};
static const AVFilterPad avfilter_vf_pad_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_output,
},
{ NULL }
};
AVFilter ff_vf_pad = {
.name = "pad",
.description = NULL_IF_CONFIG_SMALL("Pad the input video."),
.priv_size = sizeof(PadContext),
.priv_class = &pad_class,
.query_formats = query_formats,
.inputs = avfilter_vf_pad_inputs,
.outputs = avfilter_vf_pad_outputs,
};