ffmpeg/libavfilter/vf_setfield.c

   1 /*
   2  * Copyright (c) 2012 Stefano Sabatini
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 /**
  22  * @file
  23  * set field order
  24  */
  25
  26 #include "libavutil/opt.h"
  27 #include "avfilter.h"
  28 #include "internal.h"
  29 #include "video.h"
  30
  31 enum SetFieldMode {
  32     MODE_AUTO = -1,
  33     MODE_BFF,
  34     MODE_TFF,
  35     MODE_PROG,
  36 };
  37
  38 typedef struct {
  39     const AVClass *class;
  40     enum SetFieldMode mode;
  41 } SetFieldContext;
  42
  43 #define OFFSET(x) offsetof(SetFieldContext, x)
  44 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
  45
  46 static const AVOption setfield_options[] = {
  47     {"mode", "select interlace mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=MODE_AUTO}, -1, MODE_PROG, FLAGS, "mode"},
  48     {"auto", "keep the same input field",  0, AV_OPT_TYPE_CONST, {.i64=MODE_AUTO}, INT_MIN, INT_MAX, FLAGS, "mode"},
  49     {"bff",  "mark as bottom-field-first", 0, AV_OPT_TYPE_CONST, {.i64=MODE_BFF},  INT_MIN, INT_MAX, FLAGS, "mode"},
  50     {"tff",  "mark as top-field-first",    0, AV_OPT_TYPE_CONST, {.i64=MODE_TFF},  INT_MIN, INT_MAX, FLAGS, "mode"},
  51     {"prog", "mark as progressive",        0, AV_OPT_TYPE_CONST, {.i64=MODE_PROG}, INT_MIN, INT_MAX, FLAGS, "mode"},
  52     {NULL}
  53 };
  54
  55 AVFILTER_DEFINE_CLASS(setfield);
  56
  57 static int filter_frame(AVFilterLink *inlink, AVFrame *picref)
  58 {
  59     SetFieldContext *setfield = inlink->dst->priv;
  60
  61     if (setfield->mode == MODE_PROG) {
  62         picref->interlaced_frame = 0;
  63     } else if (setfield->mode != MODE_AUTO) {
  64         picref->interlaced_frame = 1;
  65         picref->top_field_first = setfield->mode;
  66     }
  67     return ff_filter_frame(inlink->dst->outputs[0], picref);
  68 }
  69
  70 static const AVFilterPad setfield_inputs[] = {
  71     {
  72         .name         = "default",
  73         .type         = AVMEDIA_TYPE_VIDEO,
  74         .filter_frame = filter_frame,
  75     },
  76     { NULL }
  77 };
  78
  79 static const AVFilterPad setfield_outputs[] = {
  80     {
  81         .name = "default",
  82         .type = AVMEDIA_TYPE_VIDEO,
  83     },
  84     { NULL }
  85 };
  86
  87 AVFilter ff_vf_setfield = {
  88     .name        = "setfield",
  89     .description = NULL_IF_CONFIG_SMALL("Force field for the output video frame."),
  90     .priv_size   = sizeof(SetFieldContext),
  91     .priv_class  = &setfield_class,
  92     .inputs      = setfield_inputs,
  93     .outputs     = setfield_outputs,
  94 };