| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | /* | ||
| 2 | * Copyright (c) 2015 Paul B Mahol | ||
| 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 "avfilter.h" | ||
| 25 | #include "filters.h" | ||
| 26 | |||
| 27 | #define MAX_FRAMES 512 | ||
| 28 | |||
| 29 | typedef struct RandomContext { | ||
| 30 | const AVClass *class; | ||
| 31 | |||
| 32 | AVLFG lfg; | ||
| 33 | int nb_frames; | ||
| 34 | int64_t random_seed; | ||
| 35 | int nb_frames_filled; | ||
| 36 | AVFrame *frames[MAX_FRAMES]; | ||
| 37 | int64_t pts[MAX_FRAMES]; | ||
| 38 | int64_t duration[MAX_FRAMES]; | ||
| 39 | int flush_idx; | ||
| 40 | } RandomContext; | ||
| 41 | |||
| 42 | #define OFFSET(x) offsetof(RandomContext, x) | ||
| 43 | #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM | ||
| 44 | |||
| 45 | static const AVOption random_options[] = { | ||
| 46 | { "frames", "set number of frames in cache", OFFSET(nb_frames), AV_OPT_TYPE_INT, {.i64=30}, 2, MAX_FRAMES, FLAGS }, | ||
| 47 | { "seed", "set the seed", OFFSET(random_seed), AV_OPT_TYPE_INT64, {.i64=-1}, -1, UINT32_MAX, FLAGS }, | ||
| 48 | { NULL } | ||
| 49 | }; | ||
| 50 | |||
| 51 | AVFILTER_DEFINE_CLASS(random); | ||
| 52 | |||
| 53 | ✗ | static av_cold int init(AVFilterContext *ctx) | |
| 54 | { | ||
| 55 | ✗ | RandomContext *s = ctx->priv; | |
| 56 | uint32_t seed; | ||
| 57 | |||
| 58 | ✗ | if (s->random_seed < 0) | |
| 59 | ✗ | s->random_seed = av_get_random_seed(); | |
| 60 | ✗ | seed = s->random_seed; | |
| 61 | ✗ | av_lfg_init(&s->lfg, seed); | |
| 62 | |||
| 63 | ✗ | return 0; | |
| 64 | } | ||
| 65 | |||
| 66 | ✗ | static int filter_frame(AVFilterLink *inlink, AVFrame *in) | |
| 67 | { | ||
| 68 | ✗ | AVFilterContext *ctx = inlink->dst; | |
| 69 | ✗ | RandomContext *s = ctx->priv; | |
| 70 | ✗ | AVFilterLink *outlink = ctx->outputs[0]; | |
| 71 | AVFrame *out; | ||
| 72 | int idx; | ||
| 73 | |||
| 74 | ✗ | if (s->nb_frames_filled < s->nb_frames) { | |
| 75 | ✗ | s->frames[s->nb_frames_filled] = in; | |
| 76 | ✗ | s->duration[s->nb_frames_filled] = in->duration; | |
| 77 | ✗ | s->pts[s->nb_frames_filled++] = in->pts; | |
| 78 | ✗ | return 0; | |
| 79 | } | ||
| 80 | |||
| 81 | ✗ | idx = av_lfg_get(&s->lfg) % s->nb_frames; | |
| 82 | |||
| 83 | ✗ | out = s->frames[idx]; | |
| 84 | ✗ | out->pts = s->pts[0]; | |
| 85 | ✗ | out->duration = s->duration[0]; | |
| 86 | ✗ | memmove(&s->pts[0], &s->pts[1], (s->nb_frames - 1) * sizeof(s->pts[0])); | |
| 87 | ✗ | memmove(&s->duration[0], &s->duration[1], (s->nb_frames - 1) * sizeof(s->duration[0])); | |
| 88 | ✗ | s->frames[idx] = in; | |
| 89 | ✗ | s->pts[s->nb_frames - 1] = in->pts; | |
| 90 | ✗ | s->duration[s->nb_frames - 1] = in->duration; | |
| 91 | |||
| 92 | ✗ | return ff_filter_frame(outlink, out); | |
| 93 | } | ||
| 94 | |||
| 95 | ✗ | static int request_frame(AVFilterLink *outlink) | |
| 96 | { | ||
| 97 | ✗ | AVFilterContext *ctx = outlink->src; | |
| 98 | ✗ | RandomContext *s = ctx->priv; | |
| 99 | int ret; | ||
| 100 | |||
| 101 | ✗ | ret = ff_request_frame(ctx->inputs[0]); | |
| 102 | |||
| 103 | ✗ | next: | |
| 104 | ✗ | if (ret == AVERROR_EOF && !ctx->is_disabled && s->nb_frames > 0) { | |
| 105 | ✗ | AVFrame *out = s->frames[s->nb_frames - 1]; | |
| 106 | ✗ | if (!out) { | |
| 107 | ✗ | s->nb_frames--; | |
| 108 | ✗ | goto next; | |
| 109 | } | ||
| 110 | ✗ | out->duration = s->duration[s->flush_idx]; | |
| 111 | ✗ | out->pts = s->pts[s->flush_idx++]; | |
| 112 | ✗ | ret = ff_filter_frame(outlink, out); | |
| 113 | ✗ | s->frames[s->nb_frames - 1] = NULL; | |
| 114 | ✗ | s->nb_frames--; | |
| 115 | } | ||
| 116 | |||
| 117 | ✗ | return ret; | |
| 118 | } | ||
| 119 | |||
| 120 | ✗ | static av_cold void uninit(AVFilterContext *ctx) | |
| 121 | { | ||
| 122 | ✗ | RandomContext *s = ctx->priv; | |
| 123 | |||
| 124 | ✗ | for (int i = 0; i < s->nb_frames; i++) | |
| 125 | ✗ | av_frame_free(&s->frames[i]); | |
| 126 | ✗ | } | |
| 127 | |||
| 128 | static const AVFilterPad random_inputs[] = { | ||
| 129 | { | ||
| 130 | .name = "default", | ||
| 131 | .type = AVMEDIA_TYPE_VIDEO, | ||
| 132 | .filter_frame = filter_frame, | ||
| 133 | }, | ||
| 134 | }; | ||
| 135 | |||
| 136 | static const AVFilterPad random_outputs[] = { | ||
| 137 | { | ||
| 138 | .name = "default", | ||
| 139 | .type = AVMEDIA_TYPE_VIDEO, | ||
| 140 | .request_frame = request_frame, | ||
| 141 | }, | ||
| 142 | }; | ||
| 143 | |||
| 144 | const AVFilter ff_vf_random = { | ||
| 145 | .name = "random", | ||
| 146 | .description = NULL_IF_CONFIG_SMALL("Return random frames."), | ||
| 147 | .priv_size = sizeof(RandomContext), | ||
| 148 | .priv_class = &random_class, | ||
| 149 | .init = init, | ||
| 150 | .uninit = uninit, | ||
| 151 | FILTER_INPUTS(random_inputs), | ||
| 152 | FILTER_OUTPUTS(random_outputs), | ||
| 153 | }; | ||
| 154 |