FFmpeg  4.4.5
f_perms.c
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1 /*
2  * Copyright (c) 2013 Clément Bœsch
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * FFmpeg is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include "libavutil/lfg.h"
22 #include "libavutil/opt.h"
23 #include "libavutil/random_seed.h"
24 #include "audio.h"
25 #include "video.h"
26 
27 enum mode {
33  NB_MODES
34 };
35 
36 typedef struct PermsContext {
37  const AVClass *class;
40  int mode;
41 } PermsContext;
42 
43 #define OFFSET(x) offsetof(PermsContext, x)
44 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_VIDEO_PARAM
45 
46 static const AVOption options[] = {
47  { "mode", "select permissions mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64 = MODE_NONE}, MODE_NONE, NB_MODES-1, FLAGS, "mode" },
48  { "none", "do nothing", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_NONE}, INT_MIN, INT_MAX, FLAGS, "mode" },
49  { "ro", "set all output frames read-only", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_RO}, INT_MIN, INT_MAX, FLAGS, "mode" },
50  { "rw", "set all output frames writable", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_RW}, INT_MIN, INT_MAX, FLAGS, "mode" },
51  { "toggle", "switch permissions", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_TOGGLE}, INT_MIN, INT_MAX, FLAGS, "mode" },
52  { "random", "set permissions randomly", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_RANDOM}, INT_MIN, INT_MAX, FLAGS, "mode" },
53  { "seed", "set the seed for the random mode", OFFSET(random_seed), AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT32_MAX, FLAGS },
54  { NULL }
55 };
56 
58 {
59  PermsContext *s = ctx->priv;
60 
61  if (s->mode == MODE_RANDOM) {
62  uint32_t seed;
63 
64  if (s->random_seed == -1)
65  s->random_seed = av_get_random_seed();
66  seed = s->random_seed;
67  av_log(ctx, AV_LOG_INFO, "random seed: 0x%08"PRIx32"\n", seed);
68  av_lfg_init(&s->lfg, seed);
69  }
70 
71  return 0;
72 }
73 
74 enum perm { RO, RW };
75 static const char * const perm_str[2] = { "RO", "RW" };
76 
77 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
78 {
79  int ret;
80  AVFilterContext *ctx = inlink->dst;
81  PermsContext *s = ctx->priv;
82  AVFrame *out = frame;
83  enum perm in_perm = av_frame_is_writable(frame) ? RW : RO;
84  enum perm out_perm;
85 
86  switch (s->mode) {
87  case MODE_TOGGLE: out_perm = in_perm == RO ? RW : RO; break;
88  case MODE_RANDOM: out_perm = av_lfg_get(&s->lfg) & 1 ? RW : RO; break;
89  case MODE_RO: out_perm = RO; break;
90  case MODE_RW: out_perm = RW; break;
91  default: out_perm = in_perm; break;
92  }
93 
94  av_log(ctx, AV_LOG_VERBOSE, "%s -> %s%s\n",
95  perm_str[in_perm], perm_str[out_perm],
96  in_perm == out_perm ? " (no-op)" : "");
97 
98  if (in_perm == RO && out_perm == RW) {
99  if ((ret = av_frame_make_writable(frame)) < 0)
100  return ret;
101  } else if (in_perm == RW && out_perm == RO) {
103  if (!out)
104  return AVERROR(ENOMEM);
105  }
106 
107  ret = ff_filter_frame(ctx->outputs[0], out);
108 
109  if (in_perm == RW && out_perm == RO)
111  return ret;
112 }
113 
114 #if CONFIG_APERMS_FILTER
115 
116 #define aperms_options options
117 AVFILTER_DEFINE_CLASS(aperms);
118 
119 static const AVFilterPad aperms_inputs[] = {
120  {
121  .name = "default",
122  .type = AVMEDIA_TYPE_AUDIO,
123  .filter_frame = filter_frame,
124  },
125  { NULL }
126 };
127 
128 static const AVFilterPad aperms_outputs[] = {
129  {
130  .name = "default",
131  .type = AVMEDIA_TYPE_AUDIO,
132  },
133  { NULL }
134 };
135 
137  .name = "aperms",
138  .description = NULL_IF_CONFIG_SMALL("Set permissions for the output audio frame."),
139  .init = init,
140  .priv_size = sizeof(PermsContext),
141  .inputs = aperms_inputs,
142  .outputs = aperms_outputs,
143  .priv_class = &aperms_class,
145 };
146 #endif /* CONFIG_APERMS_FILTER */
147 
148 #if CONFIG_PERMS_FILTER
149 
150 #define perms_options options
151 AVFILTER_DEFINE_CLASS(perms);
152 
153 static const AVFilterPad perms_inputs[] = {
154  {
155  .name = "default",
156  .type = AVMEDIA_TYPE_VIDEO,
157  .filter_frame = filter_frame,
158  },
159  { NULL }
160 };
161 
162 static const AVFilterPad perms_outputs[] = {
163  {
164  .name = "default",
165  .type = AVMEDIA_TYPE_VIDEO,
166  },
167  { NULL }
168 };
169 
171  .name = "perms",
172  .description = NULL_IF_CONFIG_SMALL("Set permissions for the output video frame."),
173  .init = init,
174  .priv_size = sizeof(PermsContext),
175  .inputs = perms_inputs,
176  .outputs = perms_outputs,
177  .priv_class = &perms_class,
179 };
180 #endif /* CONFIG_PERMS_FILTER */
static const AVFilterPad inputs[]
Definition: af_acontrast.c:193
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
AVFilter ff_vf_perms
AVFilter ff_af_aperms
#define av_cold
Definition: attributes.h:88
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1096
#define flags(name, subs,...)
Definition: cbs_av1.c:572
#define s(width, name)
Definition: cbs_vp9.c:257
#define NULL
Definition: coverity.c:32
long long int64_t
Definition: coverity.c:34
static AVFrame * frame
mode
Use these values in ebur128_init (or'ed).
Definition: ebur128.h:83
@ MODE_RW
Definition: f_perms.c:30
@ MODE_NONE
Definition: f_perms.c:28
@ NB_MODES
Definition: f_perms.c:33
@ MODE_RANDOM
Definition: f_perms.c:32
@ MODE_TOGGLE
Definition: f_perms.c:31
@ MODE_RO
Definition: f_perms.c:29
static const AVOption options[]
Definition: f_perms.c:46
static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
Definition: f_perms.c:77
#define FLAGS
Definition: f_perms.c:44
static const char *const perm_str[2]
Definition: f_perms.c:75
static av_cold int init(AVFilterContext *ctx)
Definition: f_perms.c:57
#define OFFSET(x)
Definition: f_perms.c:43
perm
Definition: f_perms.c:74
@ RO
Definition: f_perms.c:74
@ RW
Definition: f_perms.c:74
@ AV_OPT_TYPE_CONST
Definition: opt.h:234
@ AV_OPT_TYPE_INT64
Definition: opt.h:226
@ AV_OPT_TYPE_INT
Definition: opt.h:225
#define AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC
Some filters support a generic "enable" expression option that can be used to enable or disable a fil...
Definition: avfilter.h:126
uint32_t av_get_random_seed(void)
Get a seed to use in conjunction with random functions.
Definition: random_seed.c:120
#define AVERROR(e)
Definition: error.h:43
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:594
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:540
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:203
int av_frame_make_writable(AVFrame *frame)
Ensure that the frame data is writable, avoiding data copy if possible.
Definition: frame.c:611
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:210
#define AV_LOG_INFO
Standard information.
Definition: log.h:205
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
@ AVMEDIA_TYPE_VIDEO
Definition: avutil.h:201
av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:32
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:53
#define AVFILTER_DEFINE_CLASS(fname)
Definition: internal.h:288
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
AVOptions.
Describe the class of an AVClass context structure.
Definition: log.h:67
An instance of a filter.
Definition: avfilter.h:341
A filter pad used for either input or output.
Definition: internal.h:54
const char * name
Pad name.
Definition: internal.h:60
Filter definition.
Definition: avfilter.h:145
const char * name
Filter name.
Definition: avfilter.h:149
This structure describes decoded (raw) audio or video data.
Definition: frame.h:318
Context structure for the Lagged Fibonacci PRNG.
Definition: lfg.h:33
AVOption.
Definition: opt.h:248
int64_t random_seed
Definition: f_perms.c:39
int mode
Definition: f_perms.c:40
AVLFG lfg
Definition: f_perms.c:38
#define av_log(a,...)
FILE * out
Definition: movenc.c:54
AVFormatContext * ctx
Definition: movenc.c:48
static unsigned int seed
Definition: videogen.c:78