libavfilter/vf_weave.c

   1 /*
   2  * Copyright (c) 2013 Paul B Mahol
   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 #include "libavutil/imgutils.h"
  22 #include "libavutil/opt.h"
  23 #include "libavutil/pixdesc.h"
  24 #include "avfilter.h"
  25 #include "internal.h"
  26
  27 typedef struct WeaveContext {
  28     const AVClass *class;
  29     int first_field;
  30     int double_weave;
  31     int nb_planes;
  32     int planeheight[4];
  33     int linesize[4];
  34
  35     AVFrame *prev;
  36 } WeaveContext;
  37
  38 #define OFFSET(x) offsetof(WeaveContext, x)
  39 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
  40
  41 static const AVOption weave_options[] = {
  42     { "first_field", "set first field", OFFSET(first_field), AV_OPT_TYPE_INT,   {.i64=0}, 0, 1, FLAGS, "field"},
  43         { "top",     "set top field first",               0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "field"},
  44         { "t",       "set top field first",               0, AV_OPT_TYPE_CONST, {.i64=0}, 0, 0, FLAGS, "field"},
  45         { "bottom",  "set bottom field first",            0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "field"},
  46         { "b",       "set bottom field first",            0, AV_OPT_TYPE_CONST, {.i64=1}, 0, 0, FLAGS, "field"},
  47     { NULL }
  48 };
  49
  50 AVFILTER_DEFINE_CLASS(weave);
  51
  52 static int config_props_output(AVFilterLink *outlink)
  53 {
  54     AVFilterContext *ctx = outlink->src;
  55     WeaveContext *s = ctx->priv;
  56     AVFilterLink *inlink = ctx->inputs[0];
  57     const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
  58     int ret;
  59
  60     if (!s->double_weave) {
  61         outlink->time_base.num = inlink->time_base.num * 2;
  62         outlink->time_base.den = inlink->time_base.den;
  63         outlink->frame_rate.num = inlink->frame_rate.num;
  64         outlink->frame_rate.den = inlink->frame_rate.den * 2;
  65     }
  66     outlink->w = inlink->w;
  67     outlink->h = inlink->h * 2;
  68
  69     if ((ret = av_image_fill_linesizes(s->linesize, inlink->format, inlink->w)) < 0)
  70         return ret;
  71
  72     s->planeheight[1] = s->planeheight[2] = AV_CEIL_RSHIFT(inlink->h, desc->log2_chroma_h);
  73     s->planeheight[0] = s->planeheight[3] = inlink->h;
  74
  75     s->nb_planes = av_pix_fmt_count_planes(inlink->format);
  76
  77     return 0;
  78 }
  79
  80 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
  81 {
  82     AVFilterContext *ctx = inlink->dst;
  83     WeaveContext *s = ctx->priv;
  84     AVFilterLink *outlink = ctx->outputs[0];
  85     AVFrame *out;
  86     int i;
  87
  88     if (!s->prev) {
  89         s->prev = in;
  90         return 0;
  91     }
  92
  93     out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
  94     if (!out) {
  95         av_frame_free(&in);
  96         av_frame_free(&s->prev);
  97         return AVERROR(ENOMEM);
  98     }
  99     av_frame_copy_props(out, in);
 100
 101     for (i = 0; i < s->nb_planes; i++) {
 102         if (s->double_weave && !(inlink->frame_count_out & 1)) {
 103             av_image_copy_plane(out->data[i] + out->linesize[i] * !s->first_field,
 104                                 out->linesize[i] * 2,
 105                                 in->data[i], in->linesize[i],
 106                                 s->linesize[i], s->planeheight[i]);
 107             av_image_copy_plane(out->data[i] + out->linesize[i] * s->first_field,
 108                                 out->linesize[i] * 2,
 109                                 s->prev->data[i], s->prev->linesize[i],
 110                                 s->linesize[i], s->planeheight[i]);
 111         } else {
 112             av_image_copy_plane(out->data[i] + out->linesize[i] * s->first_field,
 113                                 out->linesize[i] * 2,
 114                                 in->data[i], in->linesize[i],
 115                                 s->linesize[i], s->planeheight[i]);
 116             av_image_copy_plane(out->data[i] + out->linesize[i] * !s->first_field,
 117                                 out->linesize[i] * 2,
 118                                 s->prev->data[i], s->prev->linesize[i],
 119                                 s->linesize[i], s->planeheight[i]);
 120         }
 121     }
 122
 123     out->pts = s->double_weave ? s->prev->pts : in->pts / 2;
 124     out->interlaced_frame = 1;
 125     out->top_field_first = !s->first_field;
 126
 127     if (!s->double_weave)
 128         av_frame_free(&in);
 129     av_frame_free(&s->prev);
 130     if (s->double_weave)
 131         s->prev = in;
 132     return ff_filter_frame(outlink, out);
 133 }
 134
 135 static av_cold void uninit(AVFilterContext *ctx)
 136 {
 137     WeaveContext *s = ctx->priv;
 138
 139     av_frame_free(&s->prev);
 140 }
 141
 142 static const AVFilterPad weave_inputs[] = {
 143     {
 144         .name             = "default",
 145         .type             = AVMEDIA_TYPE_VIDEO,
 146         .filter_frame     = filter_frame,
 147     },
 148     { NULL }
 149 };
 150
 151 static const AVFilterPad weave_outputs[] = {
 152     {
 153         .name          = "default",
 154         .type          = AVMEDIA_TYPE_VIDEO,
 155         .config_props  = config_props_output,
 156     },
 157     { NULL }
 158 };
 159
 160 AVFilter ff_vf_weave = {
 161     .name          = "weave",
 162     .description   = NULL_IF_CONFIG_SMALL("Weave input video fields into frames."),
 163     .priv_size     = sizeof(WeaveContext),
 164     .priv_class    = &weave_class,
 165     .uninit        = uninit,
 166     .inputs        = weave_inputs,
 167     .outputs       = weave_outputs,
 168 };
 169
 170 static av_cold int init(AVFilterContext *ctx)
 171 {
 172     WeaveContext *s = ctx->priv;
 173
 174     if (!strcmp(ctx->filter->name, "doubleweave"))
 175         s->double_weave = 1;
 176
 177     return 0;
 178 }
 179
 180 #define doubleweave_options weave_options
 181 AVFILTER_DEFINE_CLASS(doubleweave);
 182
 183 AVFilter ff_vf_doubleweave = {
 184     .name          = "doubleweave",
 185     .description   = NULL_IF_CONFIG_SMALL("Weave input video fields into double number of frames."),
 186     .priv_size     = sizeof(WeaveContext),
 187     .priv_class    = &doubleweave_class,
 188     .init          = init,
 189     .uninit        = uninit,
 190     .inputs        = weave_inputs,
 191     .outputs       = weave_outputs,
 192 };