| 1 | /* |
| 2 | * Copyright (c) 2013 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/pixdesc.h" |
| 22 | #include "avfilter.h" |
| 23 | #include "internal.h" |
| 24 | |
| 25 | typedef struct { |
| 26 | int nb_planes; |
| 27 | AVFrame *second; |
| 28 | } SeparateFieldsContext; |
| 29 | |
| 30 | static int config_props_output(AVFilterLink *outlink) |
| 31 | { |
| 32 | AVFilterContext *ctx = outlink->src; |
| 33 | SeparateFieldsContext *sf = ctx->priv; |
| 34 | AVFilterLink *inlink = ctx->inputs[0]; |
| 35 | |
| 36 | sf->nb_planes = av_pix_fmt_count_planes(inlink->format); |
| 37 | |
| 38 | if (inlink->h & 1) { |
| 39 | av_log(ctx, AV_LOG_ERROR, "height must be even\n"); |
| 40 | return AVERROR_INVALIDDATA; |
| 41 | } |
| 42 | |
| 43 | outlink->time_base.num = inlink->time_base.num; |
| 44 | outlink->time_base.den = inlink->time_base.den * 2; |
| 45 | outlink->frame_rate.num = inlink->frame_rate.num * 2; |
| 46 | outlink->frame_rate.den = inlink->frame_rate.den; |
| 47 | outlink->w = inlink->w; |
| 48 | outlink->h = inlink->h / 2; |
| 49 | |
| 50 | return 0; |
| 51 | } |
| 52 | |
| 53 | static void extract_field(AVFrame *frame, int nb_planes, int type) |
| 54 | { |
| 55 | int i; |
| 56 | |
| 57 | for (i = 0; i < nb_planes; i++) { |
| 58 | if (type) |
| 59 | frame->data[i] = frame->data[i] + frame->linesize[i]; |
| 60 | frame->linesize[i] *= 2; |
| 61 | } |
| 62 | } |
| 63 | |
| 64 | static int filter_frame(AVFilterLink *inlink, AVFrame *inpicref) |
| 65 | { |
| 66 | AVFilterContext *ctx = inlink->dst; |
| 67 | SeparateFieldsContext *sf = ctx->priv; |
| 68 | AVFilterLink *outlink = ctx->outputs[0]; |
| 69 | int ret; |
| 70 | |
| 71 | inpicref->height = outlink->h; |
| 72 | inpicref->interlaced_frame = 0; |
| 73 | |
| 74 | if (!sf->second) { |
| 75 | goto clone; |
| 76 | } else { |
| 77 | AVFrame *second = sf->second; |
| 78 | |
| 79 | extract_field(second, sf->nb_planes, second->top_field_first); |
| 80 | |
| 81 | if (second->pts != AV_NOPTS_VALUE && |
| 82 | inpicref->pts != AV_NOPTS_VALUE) |
| 83 | second->pts += inpicref->pts; |
| 84 | else |
| 85 | second->pts = AV_NOPTS_VALUE; |
| 86 | |
| 87 | ret = ff_filter_frame(outlink, second); |
| 88 | if (ret < 0) |
| 89 | return ret; |
| 90 | clone: |
| 91 | sf->second = av_frame_clone(inpicref); |
| 92 | if (!sf->second) |
| 93 | return AVERROR(ENOMEM); |
| 94 | } |
| 95 | |
| 96 | extract_field(inpicref, sf->nb_planes, !inpicref->top_field_first); |
| 97 | |
| 98 | if (inpicref->pts != AV_NOPTS_VALUE) |
| 99 | inpicref->pts *= 2; |
| 100 | |
| 101 | return ff_filter_frame(outlink, inpicref); |
| 102 | } |
| 103 | |
| 104 | static int request_frame(AVFilterLink *outlink) |
| 105 | { |
| 106 | AVFilterContext *ctx = outlink->src; |
| 107 | SeparateFieldsContext *sf = ctx->priv; |
| 108 | int ret; |
| 109 | |
| 110 | ret = ff_request_frame(ctx->inputs[0]); |
| 111 | if (ret == AVERROR_EOF && sf->second) { |
| 112 | sf->second->pts *= 2; |
| 113 | extract_field(sf->second, sf->nb_planes, sf->second->top_field_first); |
| 114 | ret = ff_filter_frame(outlink, sf->second); |
| 115 | sf->second = 0; |
| 116 | } |
| 117 | |
| 118 | return ret; |
| 119 | } |
| 120 | |
| 121 | static const AVFilterPad separatefields_inputs[] = { |
| 122 | { |
| 123 | .name = "default", |
| 124 | .type = AVMEDIA_TYPE_VIDEO, |
| 125 | .filter_frame = filter_frame, |
| 126 | }, |
| 127 | { NULL } |
| 128 | }; |
| 129 | |
| 130 | static const AVFilterPad separatefields_outputs[] = { |
| 131 | { |
| 132 | .name = "default", |
| 133 | .type = AVMEDIA_TYPE_VIDEO, |
| 134 | .config_props = config_props_output, |
| 135 | .request_frame = request_frame, |
| 136 | }, |
| 137 | { NULL } |
| 138 | }; |
| 139 | |
| 140 | AVFilter ff_vf_separatefields = { |
| 141 | .name = "separatefields", |
| 142 | .description = NULL_IF_CONFIG_SMALL("Split input video frames into fields."), |
| 143 | .priv_size = sizeof(SeparateFieldsContext), |
| 144 | .inputs = separatefields_inputs, |
| 145 | .outputs = separatefields_outputs, |
| 146 | }; |