143 lines
		
	
	
		
			4.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			143 lines
		
	
	
		
			4.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * Copyright (c) 2010 Stefano Sabatini
 | 
						|
 *
 | 
						|
 * This file is part of Libav.
 | 
						|
 *
 | 
						|
 * Libav 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.
 | 
						|
 *
 | 
						|
 * Libav 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 Libav; 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 *var_names[] = {
 | 
						|
    "E",
 | 
						|
    "PHI",
 | 
						|
    "PI",
 | 
						|
    "AVTB",   /* default timebase 1/AV_TIME_BASE */
 | 
						|
    "intb",   /* input timebase */
 | 
						|
    NULL
 | 
						|
};
 | 
						|
 | 
						|
enum var_name {
 | 
						|
    VAR_E,
 | 
						|
    VAR_PHI,
 | 
						|
    VAR_PI,
 | 
						|
    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_E]    = M_E;
 | 
						|
    settb->var_values[VAR_PHI]  = M_PHI;
 | 
						|
    settb->var_values[VAR_PI]   = M_PI;
 | 
						|
    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    = (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   = (AVFilterPad[]) {{ .name            = "default",
 | 
						|
                                    .type            = AVMEDIA_TYPE_VIDEO,
 | 
						|
                                    .config_props    = config_output_props, },
 | 
						|
                                  { .name = NULL}},
 | 
						|
};
 |