libavfilter/vf_fieldorder.c

   1 /*
   2  * Copyright (c) 2011 Mark Himsley
   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  * video field order filter, heavily influenced by vf_pad.c
  24  */
  25
  26 #include "libavutil/imgutils.h"
  27 #include "libavutil/internal.h"
  28 #include "libavutil/opt.h"
  29 #include "libavutil/pixdesc.h"
  30 #include "avfilter.h"
  31 #include "filters.h"
  32 #include "formats.h"
  33 #include "video.h"
  34
  35 typedef struct FieldOrderContext {
  36     const AVClass *class;
  37     int dst_tff;               ///< output bff/tff
  38     int          line_size[4]; ///< bytes of pixel data per line for each plane
  39 } FieldOrderContext;
  40
  41 static int query_formats(const AVFilterContext *ctx,
  42                          AVFilterFormatsConfig **cfg_in,
  43                          AVFilterFormatsConfig **cfg_out)
  44 {
  45     const AVPixFmtDescriptor *desc = NULL;
  46     AVFilterFormats  *formats;
  47     int              ret;
  48
  49     /** accept any input pixel format that is not hardware accelerated, not
  50      *  a bitstream format, and does not have vertically sub-sampled chroma */
  51     formats = NULL;
  52     while ((desc = av_pix_fmt_desc_next(desc))) {
  53         enum AVPixelFormat pix_fmt = av_pix_fmt_desc_get_id(desc);
  54         if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL ||
  55                 desc->flags & AV_PIX_FMT_FLAG_PAL     ||
  56                 desc->flags & AV_PIX_FMT_FLAG_BITSTREAM) &&
  57             desc->nb_components && !desc->log2_chroma_h &&
  58             (ret = ff_add_format(&formats, pix_fmt)) < 0)
  59             return ret;
  60     }
  61     return ff_set_common_formats2(ctx, cfg_in, cfg_out, formats);
  62 }
  63
  64 static int config_input(AVFilterLink *inlink)
  65 {
  66     AVFilterContext   *ctx = inlink->dst;
  67     FieldOrderContext *s   = ctx->priv;
  68
  69     return av_image_fill_linesizes(s->line_size, inlink->format, inlink->w);
  70 }
  71
  72 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
  73 {
  74     AVFilterContext   *ctx     = inlink->dst;
  75     FieldOrderContext *s       = ctx->priv;
  76     AVFilterLink      *outlink = ctx->outputs[0];
  77     int h, plane, src_line_step, dst_line_step, line_size, line;
  78     uint8_t *dst, *src;
  79     AVFrame *out;
  80
  81     if (!(frame->flags & AV_FRAME_FLAG_INTERLACED) ||
  82         !!(frame->flags & AV_FRAME_FLAG_TOP_FIELD_FIRST) == s->dst_tff) {
  83         av_log(ctx, AV_LOG_VERBOSE,
  84                "Skipping %s.\n",
  85                (frame->flags & AV_FRAME_FLAG_INTERLACED) ?
  86                "frame with same field order" : "progressive frame");
  87         return ff_filter_frame(outlink, frame);
  88     }
  89
  90     if (av_frame_is_writable(frame)) {
  91         out = frame;
  92     } else {
  93         out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
  94         if (!out) {
  95             av_frame_free(&frame);
  96             return AVERROR(ENOMEM);
  97         }
  98         av_frame_copy_props(out, frame);
  99     }
 100
 101     av_log(ctx, AV_LOG_TRACE,
 102             "picture will move %s one line\n",
 103             s->dst_tff ? "up" : "down");
 104     h = frame->height;
 105     for (plane = 0; plane < 4 && frame->data[plane] && frame->linesize[plane]; plane++) {
 106         dst_line_step = out->linesize[plane] * (h > 2);
 107         src_line_step = frame->linesize[plane] * (h > 2);
 108         line_size = s->line_size[plane];
 109         dst = out->data[plane];
 110         src = frame->data[plane];
 111         if (s->dst_tff) {
 112             /** Move every line up one line, working from
 113              *  the top to the bottom of the frame.
 114              *  The original top line is lost.
 115              *  The new last line is created as a copy of the
 116              *  penultimate line from that field. */
 117             for (line = 0; line < h; line++) {
 118                 if (1 + line < frame->height) {
 119                     memcpy(dst, src + src_line_step, line_size);
 120                 } else {
 121                     memcpy(dst, src - 2 * src_line_step, line_size);
 122                 }
 123                 dst += dst_line_step;
 124                 src += src_line_step;
 125             }
 126         } else {
 127             /** Move every line down one line, working from
 128              *  the bottom to the top of the frame.
 129              *  The original bottom line is lost.
 130              *  The new first line is created as a copy of the
 131              *  second line from that field. */
 132             dst += (h - 1) * dst_line_step;
 133             src += (h - 1) * src_line_step;
 134             for (line = h - 1; line >= 0 ; line--) {
 135                 if (line > 0) {
 136                     memcpy(dst, src - src_line_step, line_size);
 137                 } else {
 138                     memcpy(dst, src + 2 * src_line_step, line_size);
 139                 }
 140                 dst -= dst_line_step;
 141                 src -= src_line_step;
 142             }
 143         }
 144     }
 145 #if FF_API_INTERLACED_FRAME
 146 FF_DISABLE_DEPRECATION_WARNINGS
 147     out->top_field_first = s->dst_tff;
 148 FF_ENABLE_DEPRECATION_WARNINGS
 149 #endif
 150     if (s->dst_tff)
 151         out->flags |= AV_FRAME_FLAG_TOP_FIELD_FIRST;
 152     else
 153         out->flags &= ~AV_FRAME_FLAG_TOP_FIELD_FIRST;
 154
 155     if (frame != out)
 156         av_frame_free(&frame);
 157     return ff_filter_frame(outlink, out);
 158 }
 159
 160 #define OFFSET(x) offsetof(FieldOrderContext, x)
 161 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
 162
 163 static const AVOption fieldorder_options[] = {
 164     { "order", "output field order", OFFSET(dst_tff), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, FLAGS, .unit = "order" },
 165         { "bff", "bottom field first", 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, .flags=FLAGS, .unit = "order" },
 166         { "tff", "top field first",    0, AV_OPT_TYPE_CONST, { .i64 = 1 }, .flags=FLAGS, .unit = "order" },
 167     { NULL }
 168 };
 169
 170 AVFILTER_DEFINE_CLASS(fieldorder);
 171
 172 static const AVFilterPad avfilter_vf_fieldorder_inputs[] = {
 173     {
 174         .name         = "default",
 175         .type         = AVMEDIA_TYPE_VIDEO,
 176         .config_props = config_input,
 177         .filter_frame = filter_frame,
 178     },
 179 };
 180
 181 const FFFilter ff_vf_fieldorder = {
 182     .p.name        = "fieldorder",
 183     .p.description = NULL_IF_CONFIG_SMALL("Set the field order."),
 184     .p.priv_class  = &fieldorder_class,
 185     .p.flags       = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
 186     .priv_size     = sizeof(FieldOrderContext),
 187     FILTER_INPUTS(avfilter_vf_fieldorder_inputs),
 188     FILTER_OUTPUTS(ff_video_default_filterpad),
 189     FILTER_QUERY_FUNC2(query_formats),
 190 };