ffmpeg/libavfilter/vf_pad.c
Andreas Rheinhardt b4f5201967 avfilter: Replace query_formats callback with union of list and callback
If one looks at the many query_formats callbacks in existence,
one will immediately recognize that there is one type of default
callback for video and a slightly different default callback for
audio: It is "return ff_set_common_formats_from_list(ctx, pix_fmts);"
for video with a filter-specific pix_fmts list. For audio, it is
the same with a filter-specific sample_fmts list together with
ff_set_common_all_samplerates() and ff_set_common_all_channel_counts().

This commit allows to remove the boilerplate query_formats callbacks
by replacing said callback with a union consisting the old callback
and pointers for pixel and sample format arrays. For the not uncommon
case in which these lists only contain a single entry (besides the
sentinel) enum AVPixelFormat and enum AVSampleFormat fields are also
added to the union to store them directly in the AVFilter,
thereby avoiding a relocation.

The state of said union will be contained in a new, dedicated AVFilter
field (the nb_inputs and nb_outputs fields have been shrunk to uint8_t
in order to create a hole for this new field; this is no problem, as
the maximum of all the nb_inputs is four; for nb_outputs it is only
two).

The state's default value coincides with the earlier default of
query_formats being unset, namely that the filter accepts all formats
(and also sample rates and channel counts/layouts for audio)
provided that these properties agree coincide for all inputs and
outputs.

By using different union members for audio and video filters
the type-unsafety of using the same functions for audio and video
lists will furthermore be more confined to formats.c than before.

When the new fields are used, they will also avoid allocations:
Currently something nearly equivalent to ff_default_query_formats()
is called after every successful call to a query_formats callback;
yet in the common case that the newly allocated AVFilterFormats
are not used at all (namely if there are no free links) these newly
allocated AVFilterFormats are freed again without ever being used.
Filters no longer using the callback will not exhibit this any more.

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2021-10-05 17:48:25 +02:00

463 lines
16 KiB
C

/*
* 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 <float.h> /* DBL_MAX */
#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/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));
}
enum EvalMode {
EVAL_MODE_INIT,
EVAL_MODE_FRAME,
EVAL_MODE_NB
};
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
int inlink_w, inlink_h;
AVRational aspect;
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;
int eval_mode; ///< expression evaluation mode
} PadContext;
static int config_input(AVFilterLink *inlink)
{
AVFilterContext *ctx = inlink->dst;
PadContext *s = ctx->priv;
AVRational adjusted_aspect = s->aspect;
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;
if (!s->h)
var_values[VAR_OUT_H] = var_values[VAR_OH] = s->h = inlink->h;
/* 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;
if (!s->w)
var_values[VAR_OUT_W] = var_values[VAR_OW] = s->w = inlink->w;
if (adjusted_aspect.num && adjusted_aspect.den) {
adjusted_aspect = av_div_q(adjusted_aspect, inlink->sample_aspect_ratio);
if (s->h < av_rescale(s->w, adjusted_aspect.den, adjusted_aspect.num)) {
s->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = av_rescale(s->w, adjusted_aspect.den, adjusted_aspect.num);
} else {
s->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = av_rescale(s->h, adjusted_aspect.num, adjusted_aspect.den);
}
}
/* 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;
if (s->x < 0 || s->x + inlink->w > s->w)
s->x = var_values[VAR_X] = (s->w - inlink->w) / 2;
if (s->y < 0 || s->y + inlink->h > s->h)
s->y = var_values[VAR_Y] = (s->h - inlink->h) / 2;
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);
/* sanity check params */
if (s->w < inlink->w || s->h < inlink->h) {
av_log(ctx, AV_LOG_ERROR, "Padded dimensions cannot be smaller than input dimensions.\n");
return AVERROR(EINVAL);
}
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);
s->inlink_w = inlink->w;
s->inlink_h = 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(ctx, 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;
int plane;
if (s->inlink_w <= 0)
return NULL;
frame = ff_get_video_buffer(inlink->dst->outputs[0],
w + (s->w - s->in_w),
h + (s->h - s->in_h) + (s->x > 0));
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;
AVFilterLink *outlink = inlink->dst->outputs[0];
AVFrame *out;
int needs_copy;
if(s->eval_mode == EVAL_MODE_FRAME && (
in->width != s->inlink_w
|| in->height != s->inlink_h
|| in->format != outlink->format
|| in->sample_aspect_ratio.den != outlink->sample_aspect_ratio.den || in->sample_aspect_ratio.num != outlink->sample_aspect_ratio.num)) {
int ret;
inlink->dst->inputs[0]->format = in->format;
inlink->dst->inputs[0]->w = in->width;
inlink->dst->inputs[0]->h = in->height;
inlink->dst->inputs[0]->sample_aspect_ratio.den = in->sample_aspect_ratio.den;
inlink->dst->inputs[0]->sample_aspect_ratio.num = in->sample_aspect_ratio.num;
if ((ret = config_input(inlink)) < 0) {
s->inlink_w = -1;
return ret;
}
if ((ret = config_output(outlink)) < 0) {
s->inlink_w = -1;
return ret;
}
}
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"}, 0, 0, FLAGS },
{ "w", "set the pad area width expression", OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, 0, 0, FLAGS },
{ "height", "set the pad area height expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, 0, 0, FLAGS },
{ "h", "set the pad area height expression", OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, 0, 0, FLAGS },
{ "x", "set the x offset expression for the input image position", OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str = "0"}, 0, 0, FLAGS },
{ "y", "set the y offset expression for the input image position", OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str = "0"}, 0, 0, FLAGS },
{ "color", "set the color of the padded area border", OFFSET(rgba_color), AV_OPT_TYPE_COLOR, {.str = "black"}, .flags = FLAGS },
{ "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_INIT}, 0, EVAL_MODE_NB-1, FLAGS, "eval" },
{ "init", "eval expressions once during initialization", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_INIT}, .flags = FLAGS, .unit = "eval" },
{ "frame", "eval expressions during initialization and per-frame", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = FLAGS, .unit = "eval" },
{ "aspect", "pad to fit an aspect instead of a resolution", OFFSET(aspect), AV_OPT_TYPE_RATIONAL, {.dbl = 0}, 0, DBL_MAX, FLAGS },
{ NULL }
};
AVFILTER_DEFINE_CLASS(pad);
static const AVFilterPad avfilter_vf_pad_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_input,
.get_buffer.video = get_video_buffer,
.filter_frame = filter_frame,
},
};
static const AVFilterPad avfilter_vf_pad_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.config_props = config_output,
},
};
const AVFilter ff_vf_pad = {
.name = "pad",
.description = NULL_IF_CONFIG_SMALL("Pad the input video."),
.priv_size = sizeof(PadContext),
.priv_class = &pad_class,
FILTER_INPUTS(avfilter_vf_pad_inputs),
FILTER_OUTPUTS(avfilter_vf_pad_outputs),
FILTER_QUERY_FUNC(query_formats),
};