2 * Copyright (c) 2011 Mark Himsley
4 * This file is part of FFmpeg.
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.
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.
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
23 * video field order filter, heavily influenced by vf_pad.c
26 #include "libavutil/imgutils.h"
27 #include "libavutil/internal.h"
28 #include "libavutil/opt.h"
29 #include "libavutil/pixdesc.h"
35 typedef struct FieldOrderContext {
37 int dst_tff; ///< output bff/tff
38 int line_size[4]; ///< bytes of pixel data per line for each plane
41 static int query_formats(AVFilterContext *ctx)
43 AVFilterFormats *formats;
44 enum AVPixelFormat pix_fmt;
47 /** accept any input pixel format that is not hardware accelerated, not
48 * a bitstream format, and does not have vertically sub-sampled chroma */
50 const AVPixFmtDescriptor *desc = NULL;
52 while ((desc = av_pix_fmt_desc_next(desc))) {
53 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)
61 if ((ret = ff_formats_ref(formats, &ctx->inputs[0]->outcfg.formats)) < 0 ||
62 (ret = ff_formats_ref(formats, &ctx->outputs[0]->incfg.formats)) < 0)
69 static int config_input(AVFilterLink *inlink)
71 AVFilterContext *ctx = inlink->dst;
72 FieldOrderContext *s = ctx->priv;
74 return av_image_fill_linesizes(s->line_size, inlink->format, inlink->w);
77 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
79 AVFilterContext *ctx = inlink->dst;
80 FieldOrderContext *s = ctx->priv;
81 AVFilterLink *outlink = ctx->outputs[0];
82 int h, plane, src_line_step, dst_line_step, line_size, line;
86 if (!frame->interlaced_frame ||
87 frame->top_field_first == s->dst_tff) {
88 av_log(ctx, AV_LOG_VERBOSE,
90 frame->interlaced_frame ?
91 "frame with same field order" : "progressive frame");
92 return ff_filter_frame(outlink, frame);
95 if (av_frame_is_writable(frame)) {
98 out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
100 av_frame_free(&frame);
101 return AVERROR(ENOMEM);
103 av_frame_copy_props(out, frame);
106 av_log(ctx, AV_LOG_TRACE,
107 "picture will move %s one line\n",
108 s->dst_tff ? "up" : "down");
110 for (plane = 0; plane < 4 && frame->data[plane] && frame->linesize[plane]; plane++) {
111 dst_line_step = out->linesize[plane] * (h > 2);
112 src_line_step = frame->linesize[plane] * (h > 2);
113 line_size = s->line_size[plane];
114 dst = out->data[plane];
115 src = frame->data[plane];
117 /** Move every line up one line, working from
118 * the top to the bottom of the frame.
119 * The original top line is lost.
120 * The new last line is created as a copy of the
121 * penultimate line from that field. */
122 for (line = 0; line < h; line++) {
123 if (1 + line < frame->height) {
124 memcpy(dst, src + src_line_step, line_size);
126 memcpy(dst, src - 2 * src_line_step, line_size);
128 dst += dst_line_step;
129 src += src_line_step;
132 /** Move every line down one line, working from
133 * the bottom to the top of the frame.
134 * The original bottom line is lost.
135 * The new first line is created as a copy of the
136 * second line from that field. */
137 dst += (h - 1) * dst_line_step;
138 src += (h - 1) * src_line_step;
139 for (line = h - 1; line >= 0 ; line--) {
141 memcpy(dst, src - src_line_step, line_size);
143 memcpy(dst, src + 2 * src_line_step, line_size);
145 dst -= dst_line_step;
146 src -= src_line_step;
150 out->top_field_first = s->dst_tff;
153 av_frame_free(&frame);
154 return ff_filter_frame(outlink, out);
157 #define OFFSET(x) offsetof(FieldOrderContext, x)
158 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
160 static const AVOption fieldorder_options[] = {
161 { "order", "output field order", OFFSET(dst_tff), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, FLAGS, "order" },
162 { "bff", "bottom field first", 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, .flags=FLAGS, .unit = "order" },
163 { "tff", "top field first", 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, .flags=FLAGS, .unit = "order" },
167 AVFILTER_DEFINE_CLASS(fieldorder);
169 static const AVFilterPad avfilter_vf_fieldorder_inputs[] = {
172 .type = AVMEDIA_TYPE_VIDEO,
173 .config_props = config_input,
174 .filter_frame = filter_frame,
179 static const AVFilterPad avfilter_vf_fieldorder_outputs[] = {
182 .type = AVMEDIA_TYPE_VIDEO,
187 const AVFilter ff_vf_fieldorder = {
188 .name = "fieldorder",
189 .description = NULL_IF_CONFIG_SMALL("Set the field order."),
190 .priv_size = sizeof(FieldOrderContext),
191 .priv_class = &fieldorder_class,
192 .query_formats = query_formats,
193 .inputs = avfilter_vf_fieldorder_inputs,
194 .outputs = avfilter_vf_fieldorder_outputs,
195 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,