repositories / deb_ffmpeg.git / blame
| Commit | Line | Data |
|---|---|---|
| 2ba45a60 DM |
1 | /* |
| 2 | * Copyright (c) 2012 Stefano Sabatini | |
| 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 | /** | |
| 22 | * @file framestep filter, inspired on libmpcodecs/vf_framestep.c by | |
| 23 | * Daniele Fornighieri <guru AT digitalfantasy it>. | |
| 24 | */ | |
| 25 | ||
| 26 | #include "libavutil/opt.h" | |
| 27 | #include "avfilter.h" | |
| 28 | #include "internal.h" | |
| 29 | #include "video.h" | |
| 30 | ||
| 31 | typedef struct NullContext { | |
| 32 | const AVClass *class; | |
| 33 | int frame_step; | |
| 34 | } FrameStepContext; | |
| 35 | ||
| 36 | #define OFFSET(x) offsetof(FrameStepContext, x) | |
| 37 | #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM | |
| 38 | ||
| 39 | static const AVOption framestep_options[] = { | |
| 40 | { "step", "set frame step", OFFSET(frame_step), AV_OPT_TYPE_INT, {.i64=1}, 1, INT_MAX, FLAGS}, | |
| 41 | { NULL }, | |
| 42 | }; | |
| 43 | ||
| 44 | AVFILTER_DEFINE_CLASS(framestep); | |
| 45 | ||
| 46 | static int config_output_props(AVFilterLink *outlink) | |
| 47 | { | |
| 48 | AVFilterContext *ctx = outlink->src; | |
| 49 | FrameStepContext *framestep = ctx->priv; | |
| 50 | AVFilterLink *inlink = ctx->inputs[0]; | |
| 51 | ||
| 52 | outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP; | |
| 53 | outlink->frame_rate = | |
| 54 | av_div_q(inlink->frame_rate, (AVRational){framestep->frame_step, 1}); | |
| 55 | ||
| 56 | av_log(ctx, AV_LOG_VERBOSE, "step:%d frame_rate:%d/%d(%f) -> frame_rate:%d/%d(%f)\n", | |
| 57 | framestep->frame_step, | |
| 58 | inlink->frame_rate.num, inlink->frame_rate.den, av_q2d(inlink->frame_rate), | |
| 59 | outlink->frame_rate.num, outlink->frame_rate.den, av_q2d(outlink->frame_rate)); | |
| 60 | return 0; | |
| 61 | } | |
| 62 | ||
| 63 | static int filter_frame(AVFilterLink *inlink, AVFrame *ref) | |
| 64 | { | |
| 65 | FrameStepContext *framestep = inlink->dst->priv; | |
| 66 | ||
| 67 | if (!(inlink->frame_count % framestep->frame_step)) { | |
| 68 | return ff_filter_frame(inlink->dst->outputs[0], ref); | |
| 69 | } else { | |
| 70 | av_frame_free(&ref); | |
| 71 | return 0; | |
| 72 | } | |
| 73 | } | |
| 74 | ||
| 75 | static const AVFilterPad framestep_inputs[] = { | |
| 76 | { | |
| 77 | .name = "default", | |
| 78 | .type = AVMEDIA_TYPE_VIDEO, | |
| 79 | .filter_frame = filter_frame, | |
| 80 | }, | |
| 81 | { NULL } | |
| 82 | }; | |
| 83 | ||
| 84 | static const AVFilterPad framestep_outputs[] = { | |
| 85 | { | |
| 86 | .name = "default", | |
| 87 | .type = AVMEDIA_TYPE_VIDEO, | |
| 88 | .config_props = config_output_props, | |
| 89 | }, | |
| 90 | { NULL } | |
| 91 | }; | |
| 92 | ||
| 93 | AVFilter ff_vf_framestep = { | |
| 94 | .name = "framestep", | |
| 95 | .description = NULL_IF_CONFIG_SMALL("Select one frame every N frames."), | |
| 96 | .priv_size = sizeof(FrameStepContext), | |
| 97 | .priv_class = &framestep_class, | |
| 98 | .inputs = framestep_inputs, | |
| 99 | .outputs = framestep_outputs, | |
| 100 | .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, | |
| 101 | }; |