FFmpeg
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 
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 */
Context structure for the Lagged Fibonacci PRNG.
Definition: lfg.h:33
Definition: f_perms.c:74
#define NULL
Definition: coverity.c:32
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
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:1093
#define av_cold
Definition: attributes.h:82
AVOptions.
static const char *const perm_str[2]
Definition: f_perms.c:75
#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
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
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
perm
Definition: f_perms.c:74
#define s(width, name)
Definition: cbs_vp9.c:257
int mode
Definition: f_perms.c:40
AVFrame * av_frame_clone(const AVFrame *src)
Create a new frame that references the same data as src.
Definition: frame.c:540
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:594
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:53
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several inputs
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:611
The exact code depends on how similar the blocks are and how related they are to the and needs to apply these operations to the correct inlink or outlink if there are several Macros are available to factor that when no extra processing is inlink
#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
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
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