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 "config_components.h"
22
23 #include "libavutil/lfg.h"
24 #include "libavutil/opt.h"
25 #include "libavutil/random_seed.h"
26 #include "audio.h"
27 #include "video.h"
28
29 enum mode {
30 MODE_NONE,
31 MODE_RO,
32 MODE_RW,
33 MODE_TOGGLE,
34 MODE_RANDOM,
35 NB_MODES
36 };
37
38 typedef struct PermsContext {
39 const AVClass *class;
40 AVLFG lfg;
41 int64_t random_seed;
42 int mode;
43 } PermsContext;
44
45 #define OFFSET(x) offsetof(PermsContext, x)
46 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_VIDEO_PARAM
47 #define TFLAGS AV_OPT_FLAG_FILTERING_PARAM | AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_RUNTIME_PARAM
48
49 static const AVOption options[] = {
50 { "mode", "select permissions mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64 = MODE_NONE}, MODE_NONE, NB_MODES-1, TFLAGS, "mode" },
51 { "none", "do nothing", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_NONE}, 0, 0, TFLAGS, "mode" },
52 { "ro", "set all output frames read-only", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_RO}, 0, 0, TFLAGS, "mode" },
53 { "rw", "set all output frames writable", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_RW}, 0, 0, TFLAGS, "mode" },
54 { "toggle", "switch permissions", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_TOGGLE}, 0, 0, TFLAGS, "mode" },
55 { "random", "set permissions randomly", 0, AV_OPT_TYPE_CONST, {.i64 = MODE_RANDOM}, 0, 0, TFLAGS, "mode" },
56 { "seed", "set the seed for the random mode", OFFSET(random_seed), AV_OPT_TYPE_INT64, {.i64 = -1}, -1, UINT32_MAX, FLAGS },
57 { NULL }
58 };
59
init(AVFilterContext * ctx)60 static av_cold int init(AVFilterContext *ctx)
61 {
62 PermsContext *s = ctx->priv;
63 uint32_t seed;
64
65 if (s->random_seed == -1)
66 s->random_seed = av_get_random_seed();
67 seed = s->random_seed;
68 av_log(ctx, AV_LOG_INFO, "random seed: 0x%08"PRIx32"\n", seed);
69 av_lfg_init(&s->lfg, seed);
70
71 return 0;
72 }
73
74 enum perm { RO, RW };
75 static const char * const perm_str[2] = { "RO", "RW" };
76
filter_frame(AVFilterLink * inlink,AVFrame * frame)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 AVFILTER_DEFINE_CLASS_EXT(perms, "(a)perms", options);
115
116 #if CONFIG_APERMS_FILTER
117
118 static const AVFilterPad aperms_inputs[] = {
119 {
120 .name = "default",
121 .type = AVMEDIA_TYPE_AUDIO,
122 .filter_frame = filter_frame,
123 },
124 };
125
126 static const AVFilterPad aperms_outputs[] = {
127 {
128 .name = "default",
129 .type = AVMEDIA_TYPE_AUDIO,
130 },
131 };
132
133 const AVFilter ff_af_aperms = {
134 .name = "aperms",
135 .description = NULL_IF_CONFIG_SMALL("Set permissions for the output audio frame."),
136 .priv_class = &perms_class,
137 .init = init,
138 .priv_size = sizeof(PermsContext),
139 FILTER_INPUTS(aperms_inputs),
140 FILTER_OUTPUTS(aperms_outputs),
141 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC |
142 AVFILTER_FLAG_METADATA_ONLY,
143 .process_command = ff_filter_process_command,
144 };
145 #endif /* CONFIG_APERMS_FILTER */
146
147 #if CONFIG_PERMS_FILTER
148
149 static const AVFilterPad perms_inputs[] = {
150 {
151 .name = "default",
152 .type = AVMEDIA_TYPE_VIDEO,
153 .filter_frame = filter_frame,
154 },
155 };
156
157 static const AVFilterPad perms_outputs[] = {
158 {
159 .name = "default",
160 .type = AVMEDIA_TYPE_VIDEO,
161 },
162 };
163
164 const AVFilter ff_vf_perms = {
165 .name = "perms",
166 .description = NULL_IF_CONFIG_SMALL("Set permissions for the output video frame."),
167 .init = init,
168 .priv_size = sizeof(PermsContext),
169 FILTER_INPUTS(perms_inputs),
170 FILTER_OUTPUTS(perms_outputs),
171 .priv_class = &perms_class,
172 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC |
173 AVFILTER_FLAG_METADATA_ONLY,
174 .process_command = ff_filter_process_command,
175 };
176 #endif /* CONFIG_PERMS_FILTER */
177