FFmpeg/libavfilter/f_perms.c
2020-12-07 21:09:08 +01:00

181 lines
5.6 KiB
C

/*
* Copyright (c) 2013 Clément Bœsch
*
* 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
*/
#include "libavutil/lfg.h"
#include "libavutil/opt.h"
#include "libavutil/random_seed.h"
#include "audio.h"
#include "video.h"
enum mode {
MODE_NONE,
MODE_RO,
MODE_RW,
MODE_TOGGLE,
MODE_RANDOM,
NB_MODES
};
typedef struct PermsContext {
const AVClass *class;
AVLFG lfg;
int64_t random_seed;
int mode;
} PermsContext;
#define OFFSET(x) offsetof(PermsContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_VIDEO_PARAM
static const AVOption options[] = {
{ "mode", "select permissions mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64 = MODE_NONE}, MODE_NONE, NB_MODES-1, FLAGS, "mode" },
{ "none", "do nothing", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_NONE}, INT_MIN, INT_MAX, FLAGS, "mode" },
{ "ro", "set all output frames read-only", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_RO}, INT_MIN, INT_MAX, FLAGS, "mode" },
{ "rw", "set all output frames writable", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_RW}, INT_MIN, INT_MAX, FLAGS, "mode" },
{ "toggle", "switch permissions", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_TOGGLE}, INT_MIN, INT_MAX, FLAGS, "mode" },
{ "random", "set permissions randomly", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_RANDOM}, INT_MIN, INT_MAX, FLAGS, "mode" },
{ "seed", "set the seed for the random mode", OFFSET(random_seed), AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT32_MAX, FLAGS },
{ NULL }
};
static av_cold int init(AVFilterContext *ctx)
{
PermsContext *s = ctx->priv;
if (s->mode == MODE_RANDOM) {
uint32_t seed;
if (s->random_seed == -1)
s->random_seed = av_get_random_seed();
seed = s->random_seed;
av_log(ctx, AV_LOG_INFO, "random seed: 0x%08"PRIx32"\n", seed);
av_lfg_init(&s->lfg, seed);
}
return 0;
}
enum perm { RO, RW };
static const char * const perm_str[2] = { "RO", "RW" };
static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
{
int ret;
AVFilterContext *ctx = inlink->dst;
PermsContext *s = ctx->priv;
AVFrame *out = frame;
enum perm in_perm = av_frame_is_writable(frame) ? RW : RO;
enum perm out_perm;
switch (s->mode) {
case MODE_TOGGLE: out_perm = in_perm == RO ? RW : RO; break;
case MODE_RANDOM: out_perm = av_lfg_get(&s->lfg) & 1 ? RW : RO; break;
case MODE_RO: out_perm = RO; break;
case MODE_RW: out_perm = RW; break;
default: out_perm = in_perm; break;
}
av_log(ctx, AV_LOG_VERBOSE, "%s -> %s%s\n",
perm_str[in_perm], perm_str[out_perm],
in_perm == out_perm ? " (no-op)" : "");
if (in_perm == RO && out_perm == RW) {
if ((ret = av_frame_make_writable(frame)) < 0)
return ret;
} else if (in_perm == RW && out_perm == RO) {
out = av_frame_clone(frame);
if (!out)
return AVERROR(ENOMEM);
}
ret = ff_filter_frame(ctx->outputs[0], out);
if (in_perm == RW && out_perm == RO)
av_frame_free(&frame);
return ret;
}
#if CONFIG_APERMS_FILTER
#define aperms_options options
AVFILTER_DEFINE_CLASS(aperms);
static const AVFilterPad aperms_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
.filter_frame = filter_frame,
},
{ NULL }
};
static const AVFilterPad aperms_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_AUDIO,
},
{ NULL }
};
AVFilter ff_af_aperms = {
.name = "aperms",
.description = NULL_IF_CONFIG_SMALL("Set permissions for the output audio frame."),
.init = init,
.priv_size = sizeof(PermsContext),
.inputs = aperms_inputs,
.outputs = aperms_outputs,
.priv_class = &aperms_class,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};
#endif /* CONFIG_APERMS_FILTER */
#if CONFIG_PERMS_FILTER
#define perms_options options
AVFILTER_DEFINE_CLASS(perms);
static const AVFilterPad perms_inputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
.filter_frame = filter_frame,
},
{ NULL }
};
static const AVFilterPad perms_outputs[] = {
{
.name = "default",
.type = AVMEDIA_TYPE_VIDEO,
},
{ NULL }
};
AVFilter ff_vf_perms = {
.name = "perms",
.description = NULL_IF_CONFIG_SMALL("Set permissions for the output video frame."),
.init = init,
.priv_size = sizeof(PermsContext),
.inputs = perms_inputs,
.outputs = perms_outputs,
.priv_class = &perms_class,
.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};
#endif /* CONFIG_PERMS_FILTER */