| /* |
| * CEA-708 Closed Caption Repacker |
| * Copyright (c) 2023 LTN Global Communications |
| * |
| * Author: Devin Heitmueller <dheitmueller@ltnglobal.com> |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| /* |
| * Repackage CEA-708 arrays, which deals with incorrect cc_count for a given |
| * output framerate, and incorrect 708 padding. |
| * |
| * See CEA CEA-10-A "EIA-708-B Implementation Guidance", Section 26.5 |
| * "Grouping DTVCC Data Within user_data() Structure" |
| */ |
| |
| #include "avfilter.h" |
| #include "internal.h" |
| #include "ccfifo.h" |
| #include "video.h" |
| #include "libavutil/opt.h" |
| |
| typedef struct CCRepackContext |
| { |
| const AVClass *class; |
| CCFifo cc_fifo; |
| } CCRepackContext; |
| |
| static const AVOption ccrepack_options[] = { |
| { NULL } |
| }; |
| |
| AVFILTER_DEFINE_CLASS(ccrepack); |
| |
| static int config_input(AVFilterLink *link) |
| { |
| CCRepackContext *ctx = link->dst->priv; |
| |
| int ret = ff_ccfifo_init(&ctx->cc_fifo, link->frame_rate, ctx); |
| if (ret < 0) { |
| av_log(ctx, AV_LOG_ERROR, "Failure to setup CC FIFO queue\n"); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int filter_frame(AVFilterLink *inlink, AVFrame *frame) |
| { |
| CCRepackContext *ctx = inlink->dst->priv; |
| AVFilterLink *outlink = inlink->dst->outputs[0]; |
| |
| ff_ccfifo_extract(&ctx->cc_fifo, frame); |
| ff_ccfifo_inject(&ctx->cc_fifo, frame); |
| |
| return ff_filter_frame(outlink, frame); |
| } |
| |
| static av_cold void uninit(AVFilterContext *ctx) |
| { |
| CCRepackContext *s = ctx->priv; |
| ff_ccfifo_uninit(&s->cc_fifo); |
| } |
| |
| static const AVFilterPad avfilter_vf_ccrepack_inputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, |
| .filter_frame = filter_frame, |
| .config_props = config_input, |
| }, |
| }; |
| |
| const AVFilter ff_vf_ccrepack = { |
| .name = "ccrepack", |
| .description = NULL_IF_CONFIG_SMALL("Repack CEA-708 closed caption metadata"), |
| .uninit = uninit, |
| .priv_size = sizeof(CCRepackContext), |
| .priv_class = &ccrepack_class, |
| FILTER_INPUTS(avfilter_vf_ccrepack_inputs), |
| FILTER_OUTPUTS(ff_video_default_filterpad), |
| }; |