| /* |
| * Copyright (c) 2010 Stefano Sabatini |
| * |
| * 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 |
| * Set timebase for the output link. |
| */ |
| |
| #include "libavutil/avstring.h" |
| #include "libavutil/eval.h" |
| #include "libavutil/mathematics.h" |
| #include "libavutil/rational.h" |
| #include "avfilter.h" |
| #include "internal.h" |
| |
| static const char * const var_names[] = { |
| "AVTB", /* default timebase 1/AV_TIME_BASE */ |
| "intb", /* input timebase */ |
| NULL |
| }; |
| |
| enum var_name { |
| VAR_AVTB, |
| VAR_INTB, |
| VAR_VARS_NB |
| }; |
| |
| typedef struct { |
| char tb_expr[256]; |
| double var_values[VAR_VARS_NB]; |
| } SetTBContext; |
| |
| static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque) |
| { |
| SetTBContext *settb = ctx->priv; |
| av_strlcpy(settb->tb_expr, "intb", sizeof(settb->tb_expr)); |
| |
| if (args) |
| sscanf(args, "%255[^:]", settb->tb_expr); |
| |
| return 0; |
| } |
| |
| static int config_output_props(AVFilterLink *outlink) |
| { |
| AVFilterContext *ctx = outlink->src; |
| SetTBContext *settb = ctx->priv; |
| AVFilterLink *inlink = ctx->inputs[0]; |
| AVRational time_base; |
| int ret; |
| double res; |
| |
| settb->var_values[VAR_AVTB] = av_q2d(AV_TIME_BASE_Q); |
| settb->var_values[VAR_INTB] = av_q2d(inlink->time_base); |
| |
| outlink->w = inlink->w; |
| outlink->h = inlink->h; |
| |
| if ((ret = av_expr_parse_and_eval(&res, settb->tb_expr, var_names, settb->var_values, |
| NULL, NULL, NULL, NULL, NULL, 0, NULL)) < 0) { |
| av_log(ctx, AV_LOG_ERROR, "Invalid expression '%s' for timebase.\n", settb->tb_expr); |
| return ret; |
| } |
| time_base = av_d2q(res, INT_MAX); |
| if (time_base.num <= 0 || time_base.den <= 0) { |
| av_log(ctx, AV_LOG_ERROR, |
| "Invalid non-positive values for the timebase num:%d or den:%d.\n", |
| time_base.num, time_base.den); |
| return AVERROR(EINVAL); |
| } |
| |
| outlink->time_base = time_base; |
| av_log(outlink->src, AV_LOG_INFO, "tb:%d/%d -> tb:%d/%d\n", |
| inlink ->time_base.num, inlink ->time_base.den, |
| outlink->time_base.num, outlink->time_base.den); |
| |
| return 0; |
| } |
| |
| static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *picref) |
| { |
| AVFilterContext *ctx = inlink->dst; |
| AVFilterLink *outlink = ctx->outputs[0]; |
| AVFilterBufferRef *picref2 = picref; |
| |
| if (av_cmp_q(inlink->time_base, outlink->time_base)) { |
| picref2 = avfilter_ref_buffer(picref, ~0); |
| picref2->pts = av_rescale_q(picref->pts, inlink->time_base, outlink->time_base); |
| av_log(ctx, AV_LOG_DEBUG, "tb:%d/%d pts:%"PRId64" -> tb:%d/%d pts:%"PRId64"\n", |
| inlink ->time_base.num, inlink ->time_base.den, picref ->pts, |
| outlink->time_base.num, outlink->time_base.den, picref2->pts); |
| avfilter_unref_buffer(picref); |
| } |
| |
| avfilter_start_frame(outlink, picref2); |
| } |
| |
| AVFilter avfilter_vf_settb = { |
| .name = "settb", |
| .description = NULL_IF_CONFIG_SMALL("Set timebase for the output link."), |
| .init = init, |
| |
| .priv_size = sizeof(SetTBContext), |
| |
| .inputs = (const AVFilterPad[]) {{ .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, |
| .get_video_buffer = avfilter_null_get_video_buffer, |
| .start_frame = start_frame, |
| .end_frame = avfilter_null_end_frame }, |
| { .name = NULL }}, |
| |
| .outputs = (const AVFilterPad[]) {{ .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, |
| .config_props = config_output_props, }, |
| { .name = NULL}}, |
| }; |