FFmpeg  4.0
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 {
34 };
35 
36 typedef struct PermsContext {
37  const AVClass *class;
39  int64_t random_seed;
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)
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) {
102  out = av_frame_clone(frame);
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)
110  av_frame_free(&frame);
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,
144 };
145 #endif /* CONFIG_APERMS_FILTER */
146 
147 #if CONFIG_PERMS_FILTER
148 
149 #define perms_options options
150 AVFILTER_DEFINE_CLASS(perms);
151 
152 static const AVFilterPad perms_inputs[] = {
153  {
154  .name = "default",
155  .type = AVMEDIA_TYPE_VIDEO,
156  .filter_frame = filter_frame,
157  },
158  { NULL }
159 };
160 
161 static const AVFilterPad perms_outputs[] = {
162  {
163  .name = "default",
164  .type = AVMEDIA_TYPE_VIDEO,
165  },
166  { NULL }
167 };
168 
170  .name = "perms",
171  .description = NULL_IF_CONFIG_SMALL("Set permissions for the output video frame."),
172  .init = init,
173  .priv_size = sizeof(PermsContext),
174  .inputs = perms_inputs,
175  .outputs = perms_outputs,
176  .priv_class = &perms_class,
177 };
178 #endif /* CONFIG_PERMS_FILTER */
Definition: lfg.h:27
Definition: f_perms.c:74
#define NULL
Definition: coverity.c:32
const char * s
Definition: avisynth_c.h:768
This structure describes decoded (raw) audio or video data.
Definition: frame.h:218
AVOption.
Definition: opt.h:246
const char * name
Pad name.
Definition: internal.h:60
int ff_filter_frame(AVFilterLink *link, AVFrame *frame)
Send a frame of data to the next filter.
Definition: avfilter.c:1080
#define av_cold
Definition: attributes.h:82
AVOptions.
static const char *const perm_str[2]
Definition: f_perms.c:75
static AVFrame * frame
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
static const AVOption options[]
Definition: f_perms.c:46
#define av_log(a,...)
A filter pad used for either input or output.
Definition: internal.h:54
AVLFG lfg
Definition: f_perms.c:38
#define AVERROR(e)
Definition: error.h:43
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
void * priv
private data for use by the filter
Definition: avfilter.h:353
int64_t random_seed
Definition: f_perms.c:39
Definition: f_perms.c:74
#define FLAGS
Definition: f_perms.c:44
AVFormatContext * ctx
Definition: movenc.c:48
perm
Definition: f_perms.c:74
int mode
Definition: f_perms.c:40
static const AVFilterPad inputs[]
Definition: af_acontrast.c:193
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:538
static const AVFilterPad outputs[]
Definition: af_acontrast.c:203
static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
Definition: f_perms.c:77
#define AV_LOG_INFO
Standard information.
Definition: log.h:187
int av_frame_is_writable(AVFrame *frame)
Check if the frame data is writable.
Definition: frame.c:592
AVFilter ff_af_aperms
static unsigned int seed
Definition: videogen.c:78
static unsigned int av_lfg_get(AVLFG *c)
Get the next random unsigned 32-bit number using an ALFG.
Definition: lfg.h:47
Describe the class of an AVClass context structure.
Definition: log.h:67
Filter definition.
Definition: avfilter.h:144
const char * name
Filter name.
Definition: avfilter.h:148
av_cold void av_lfg_init(AVLFG *c, unsigned int seed)
Definition: lfg.c:32
AVFilterLink ** outputs
array of pointers to output links
Definition: avfilter.h:350
int av_frame_make_writable(AVFrame *frame)
Ensure that the frame data is writable, avoiding data copy if possible.
Definition: frame.c:609
#define OFFSET(x)
Definition: f_perms.c:43
AVFilter ff_vf_perms
#define AVFILTER_DEFINE_CLASS(fname)
Definition: internal.h:334
An instance of a filter.
Definition: avfilter.h:338
FILE * out
Definition: movenc.c:54
uint32_t av_get_random_seed(void)
Get a seed to use in conjunction with random functions.
Definition: random_seed.c:120
mode
Use these values in ebur128_init (or&#39;ed).
Definition: ebur128.h:83
static av_cold int init(AVFilterContext *ctx)
Definition: f_perms.c:57