| /* |
| * Copyright (c) 2010 Stefano Sabatini |
| * Copyright (c) 2008 Victor Paesa |
| * |
| * 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 |
| * video presentation timestamp (PTS) modification filter |
| */ |
| |
| /* #define DEBUG */ |
| |
| #include "libavutil/eval.h" |
| #include "libavutil/mathematics.h" |
| #include "avfilter.h" |
| #include "video.h" |
| |
| static const char *const var_names[] = { |
| "INTERLACED", ///< tell if the current frame is interlaced |
| "N", ///< frame number (starting at zero) |
| "POS", ///< original position in the file of the frame |
| "PREV_INPTS", ///< previous input PTS |
| "PREV_OUTPTS", ///< previous output PTS |
| "PTS", ///< original pts in the file of the frame |
| "STARTPTS", ///< PTS at start of movie |
| "TB", ///< timebase |
| NULL |
| }; |
| |
| enum var_name { |
| VAR_INTERLACED, |
| VAR_N, |
| VAR_POS, |
| VAR_PREV_INPTS, |
| VAR_PREV_OUTPTS, |
| VAR_PTS, |
| VAR_STARTPTS, |
| VAR_TB, |
| VAR_VARS_NB |
| }; |
| |
| typedef struct { |
| AVExpr *expr; |
| double var_values[VAR_VARS_NB]; |
| } SetPTSContext; |
| |
| static av_cold int init(AVFilterContext *ctx, const char *args, void *opaque) |
| { |
| SetPTSContext *setpts = ctx->priv; |
| int ret; |
| |
| if ((ret = av_expr_parse(&setpts->expr, args ? args : "PTS", |
| var_names, NULL, NULL, NULL, NULL, 0, ctx)) < 0) { |
| av_log(ctx, AV_LOG_ERROR, "Error while parsing expression '%s'\n", args); |
| return ret; |
| } |
| |
| setpts->var_values[VAR_N ] = 0.0; |
| setpts->var_values[VAR_PREV_INPTS ] = NAN; |
| setpts->var_values[VAR_PREV_OUTPTS] = NAN; |
| setpts->var_values[VAR_STARTPTS ] = NAN; |
| return 0; |
| } |
| |
| static int config_input(AVFilterLink *inlink) |
| { |
| SetPTSContext *setpts = inlink->dst->priv; |
| |
| setpts->var_values[VAR_TB] = av_q2d(inlink->time_base); |
| |
| av_log(inlink->src, AV_LOG_INFO, "TB:%f\n", setpts->var_values[VAR_TB]); |
| return 0; |
| } |
| |
| #define D2TS(d) (isnan(d) ? AV_NOPTS_VALUE : (int64_t)(d)) |
| #define TS2D(ts) ((ts) == AV_NOPTS_VALUE ? NAN : (double)(ts)) |
| |
| static void start_frame(AVFilterLink *inlink, AVFilterBufferRef *inpicref) |
| { |
| SetPTSContext *setpts = inlink->dst->priv; |
| double d; |
| AVFilterBufferRef *outpicref = avfilter_ref_buffer(inpicref, ~0); |
| |
| if (isnan(setpts->var_values[VAR_STARTPTS])) |
| setpts->var_values[VAR_STARTPTS] = TS2D(inpicref->pts); |
| |
| setpts->var_values[VAR_INTERLACED] = inpicref->video->interlaced; |
| setpts->var_values[VAR_PTS ] = TS2D(inpicref->pts); |
| setpts->var_values[VAR_POS ] = inpicref->pos == -1 ? NAN : inpicref->pos; |
| |
| d = av_expr_eval(setpts->expr, setpts->var_values, NULL); |
| outpicref->pts = D2TS(d); |
| |
| #ifdef DEBUG |
| av_log(inlink->dst, AV_LOG_DEBUG, |
| "n:%"PRId64" interlaced:%d pos:%"PRId64" pts:%"PRId64" t:%f -> pts:%"PRId64" t:%f\n", |
| (int64_t)setpts->var_values[VAR_N], |
| (int)setpts->var_values[VAR_INTERLACED], |
| inpicref ->pos, |
| inpicref ->pts, inpicref ->pts * av_q2d(inlink->time_base), |
| outpicref->pts, outpicref->pts * av_q2d(inlink->time_base)); |
| #endif |
| |
| setpts->var_values[VAR_N] += 1.0; |
| setpts->var_values[VAR_PREV_INPTS ] = TS2D(inpicref ->pts); |
| setpts->var_values[VAR_PREV_OUTPTS] = TS2D(outpicref->pts); |
| avfilter_start_frame(inlink->dst->outputs[0], outpicref); |
| } |
| |
| static av_cold void uninit(AVFilterContext *ctx) |
| { |
| SetPTSContext *setpts = ctx->priv; |
| av_expr_free(setpts->expr); |
| setpts->expr = NULL; |
| } |
| |
| AVFilter avfilter_vf_setpts = { |
| .name = "setpts", |
| .description = NULL_IF_CONFIG_SMALL("Set PTS for the output video frame."), |
| .init = init, |
| .uninit = uninit, |
| |
| .priv_size = sizeof(SetPTSContext), |
| |
| .inputs = (const AVFilterPad[]) {{ .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, |
| .get_video_buffer = ff_null_get_video_buffer, |
| .config_props = config_input, |
| .start_frame = start_frame, }, |
| { .name = NULL }}, |
| .outputs = (const AVFilterPad[]) {{ .name = "default", |
| .type = AVMEDIA_TYPE_VIDEO, }, |
| { .name = NULL}}, |
| }; |