| /* |
| * Copyright (c) 2023 Thilo Borgmann <thilo.borgmann _at_ mail.de> |
| * |
| * 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 |
| */ |
| |
| /** |
| * @file |
| * Filter for syncing video frames from external source |
| * |
| * @author Thilo Borgmann <thilo.borgmann _at_ mail.de> |
| */ |
| |
| #include "libavutil/avstring.h" |
| #include "libavutil/error.h" |
| #include "libavutil/mem.h" |
| #include "libavutil/opt.h" |
| #include "libavformat/avio.h" |
| #include "video.h" |
| #include "filters.h" |
| |
| #define BUF_SIZE 256 |
| |
| typedef struct FsyncContext { |
| const AVClass *class; |
| AVIOContext *avio_ctx; // reading the map file |
| AVFrame *last_frame; // buffering the last frame for duplicating eventually |
| char *filename; // user-specified map file |
| char *buf; // line buffer for the map file |
| char *cur; // current position in the line buffer |
| char *end; // end pointer of the line buffer |
| int64_t ptsi; // input pts to map to [0-N] output pts |
| int64_t pts; // output pts |
| int tb_num; // output timebase num |
| int tb_den; // output timebase den |
| } FsyncContext; |
| |
| #define OFFSET(x) offsetof(FsyncContext, x) |
| |
| static const AVOption fsync_options[] = { |
| { "file", "set the file name to use for frame sync", OFFSET(filename), AV_OPT_TYPE_STRING, { .str = "" }, .flags= AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_FILTERING_PARAM }, |
| { "f", "set the file name to use for frame sync", OFFSET(filename), AV_OPT_TYPE_STRING, { .str = "" }, .flags= AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_FILTERING_PARAM }, |
| { NULL } |
| }; |
| |
| /** |
| * Fills the buffer from cur to end, add \0 at EOF |
| */ |
| static int buf_fill(FsyncContext *ctx) |
| { |
| int ret; |
| int num = ctx->end - ctx->cur; |
| |
| ret = avio_read(ctx->avio_ctx, ctx->cur, num); |
| if (ret < 0) |
| return ret; |
| if (ret < num) { |
| *(ctx->cur + ret) = '\0'; |
| } |
| |
| return ret; |
| } |
| |
| /** |
| * Copies cur to end to the beginning and fills the rest |
| */ |
| static int buf_reload(FsyncContext *ctx) |
| { |
| int i, ret; |
| int num = ctx->end - ctx->cur; |
| |
| for (i = 0; i < num; i++) { |
| ctx->buf[i] = *ctx->cur++; |
| } |
| |
| ctx->cur = ctx->buf + i; |
| ret = buf_fill(ctx); |
| if (ret < 0) |
| return ret; |
| ctx->cur = ctx->buf; |
| |
| return ret; |
| } |
| |
| /** |
| * Skip from cur over eol |
| */ |
| static void buf_skip_eol(FsyncContext *ctx) |
| { |
| char *i; |
| for (i = ctx->cur; i < ctx->end; i++) { |
| if (*i != '\n')// && *i != '\r') |
| break; |
| } |
| ctx->cur = i; |
| } |
| |
| /** |
| * Get number of bytes from cur until eol |
| * |
| * @return >= 0 in case of success, |
| * -1 in case there is no line ending before end of buffer |
| */ |
| static int buf_get_line_count(FsyncContext *ctx) |
| { |
| int ret = 0; |
| char *i; |
| for (i = ctx->cur; i < ctx->end; i++, ret++) { |
| if (*i == '\0' || *i == '\n') |
| return ret; |
| } |
| |
| return -1; |
| } |
| |
| /** |
| * Get number of bytes from cur to '\0' |
| */ |
| static int buf_get_zero(FsyncContext *ctx) |
| { |
| return av_strnlen(ctx->cur, ctx->end - ctx->cur); |
| } |
| |
| static int activate(AVFilterContext *ctx) |
| { |
| FsyncContext *s = ctx->priv; |
| AVFilterLink *inlink = ctx->inputs[0]; |
| AVFilterLink *outlink = ctx->outputs[0]; |
| |
| int ret, line_count; |
| AVFrame *frame; |
| |
| FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink); |
| |
| buf_skip_eol(s); |
| line_count = buf_get_line_count(s); |
| if (line_count < 0) { |
| line_count = buf_reload(s); |
| if (line_count < 0) |
| return line_count; |
| line_count = buf_get_line_count(s); |
| if (line_count < 0) |
| return line_count; |
| } |
| |
| if (avio_feof(s->avio_ctx) && buf_get_zero(s) < 3) { |
| av_log(ctx, AV_LOG_DEBUG, "End of file. To zero = %i\n", buf_get_zero(s)); |
| goto end; |
| } |
| |
| if (s->last_frame) { |
| ret = av_sscanf(s->cur, "%"PRId64" %"PRId64" %d/%d", &s->ptsi, &s->pts, &s->tb_num, &s->tb_den); |
| if (ret != 4) { |
| av_log(ctx, AV_LOG_ERROR, "Unexpected format found (%i / 4).\n", ret); |
| ff_outlink_set_status(outlink, AVERROR_INVALIDDATA, AV_NOPTS_VALUE); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| av_log(ctx, AV_LOG_DEBUG, "frame %"PRId64" ", s->last_frame->pts); |
| |
| if (s->last_frame->pts >= s->ptsi) { |
| av_log(ctx, AV_LOG_DEBUG, ">= %"PRId64": DUP LAST with pts = %"PRId64"\n", s->ptsi, s->pts); |
| |
| // clone frame |
| frame = av_frame_clone(s->last_frame); |
| if (!frame) { |
| ff_outlink_set_status(outlink, AVERROR(ENOMEM), AV_NOPTS_VALUE); |
| return AVERROR(ENOMEM); |
| } |
| |
| // set output pts and timebase |
| frame->pts = s->pts; |
| frame->time_base = av_make_q((int)s->tb_num, (int)s->tb_den); |
| |
| // advance cur to eol, skip over eol in the next call |
| s->cur += line_count; |
| |
| // call again |
| if (ff_inoutlink_check_flow(inlink, outlink)) |
| ff_filter_set_ready(ctx, 100); |
| |
| // filter frame |
| return ff_filter_frame(outlink, frame); |
| } else if (s->last_frame->pts < s->ptsi) { |
| av_log(ctx, AV_LOG_DEBUG, "< %"PRId64": DROP\n", s->ptsi); |
| av_frame_free(&s->last_frame); |
| |
| // call again |
| if (ff_inoutlink_check_flow(inlink, outlink)) |
| ff_filter_set_ready(ctx, 100); |
| |
| return 0; |
| } |
| } |
| |
| end: |
| if (s->last_frame) |
| av_frame_free(&s->last_frame); |
| |
| ret = ff_inlink_consume_frame(inlink, &s->last_frame); |
| if (ret < 0) |
| return ret; |
| |
| FF_FILTER_FORWARD_STATUS(inlink, outlink); |
| FF_FILTER_FORWARD_WANTED(outlink, inlink); |
| |
| return FFERROR_NOT_READY; |
| } |
| |
| static int fsync_config_props(AVFilterLink* outlink) |
| { |
| AVFilterContext *ctx = outlink->src; |
| FsyncContext *s = ctx->priv; |
| int ret; |
| |
| // read first line to get output timebase |
| ret = av_sscanf(s->cur, "%"PRId64" %"PRId64" %d/%d", &s->ptsi, &s->pts, &s->tb_num, &s->tb_den); |
| if (ret != 4) { |
| av_log(ctx, AV_LOG_ERROR, "Unexpected format found (%i of 4).\n", ret); |
| ff_outlink_set_status(outlink, AVERROR_INVALIDDATA, AV_NOPTS_VALUE); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| outlink->frame_rate = av_make_q(1, 0); // unknown or dynamic |
| outlink->time_base = av_make_q(s->tb_num, s->tb_den); |
| |
| return 0; |
| } |
| |
| static av_cold int fsync_init(AVFilterContext *ctx) |
| { |
| FsyncContext *s = ctx->priv; |
| int ret; |
| |
| av_log(ctx, AV_LOG_DEBUG, "filename: %s\n", s->filename); |
| |
| s->buf = av_malloc(BUF_SIZE + 1); |
| if (!s->buf) |
| return AVERROR(ENOMEM); |
| |
| ret = avio_open(&s->avio_ctx, s->filename, AVIO_FLAG_READ); |
| if (ret < 0) |
| return ret; |
| |
| s->cur = s->buf; |
| s->end = s->buf + BUF_SIZE; |
| s->buf[BUF_SIZE] = '\0'; |
| |
| ret = buf_fill(s); |
| if (ret < 0) |
| return ret; |
| |
| |
| return 0; |
| } |
| |
| static av_cold void fsync_uninit(AVFilterContext *ctx) |
| { |
| FsyncContext *s = ctx->priv; |
| |
| avio_closep(&s->avio_ctx); |
| av_freep(&s->buf); |
| av_frame_free(&s->last_frame); |
| } |
| |
| AVFILTER_DEFINE_CLASS(fsync); |
| |
| static const AVFilterPad fsync_outputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, |
| .config_props = fsync_config_props, |
| }, |
| }; |
| |
| const AVFilter ff_vf_fsync = { |
| .name = "fsync", |
| .description = NULL_IF_CONFIG_SMALL("Synchronize video frames from external source."), |
| .init = fsync_init, |
| .uninit = fsync_uninit, |
| .priv_size = sizeof(FsyncContext), |
| .priv_class = &fsync_class, |
| .activate = activate, |
| .formats_state = FF_FILTER_FORMATS_PASSTHROUGH, |
| FILTER_INPUTS(ff_video_default_filterpad), |
| FILTER_OUTPUTS(fsync_outputs), |
| .flags = AVFILTER_FLAG_METADATA_ONLY, |
| }; |