2 * Copyright (c) 2011 Mark Himsley
4 * This file is part of Libav.
6 * Libav 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 * Libav 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 Libav; 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
29 #include "libavutil/imgutils.h"
30 #include "libavutil/internal.h"
31 #include "libavutil/opt.h"
32 #include "libavutil/pixdesc.h"
41 int dst_tff; ///< output bff/tff
42 int line_size[4]; ///< bytes of pixel data per line for each plane
45 static int query_formats(AVFilterContext *ctx)
47 AVFilterFormats *formats;
48 enum AVPixelFormat pix_fmt;
51 /** accept any input pixel format that is not hardware accelerated, not
52 * a bitstream format, and does not have vertically sub-sampled chroma */
55 for (pix_fmt = 0; pix_fmt < AV_PIX_FMT_NB; pix_fmt++) {
56 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
57 if (!(desc->flags & AV_PIX_FMT_FLAG_HWACCEL ||
58 desc->flags & AV_PIX_FMT_FLAG_BITSTREAM) &&
59 desc->nb_components && !desc->log2_chroma_h &&
60 (ret = ff_add_format(&formats, pix_fmt)) < 0) {
61 ff_formats_unref(&formats);
65 ff_formats_ref(formats, &ctx->inputs[0]->out_formats);
66 ff_formats_ref(formats, &ctx->outputs[0]->in_formats);
72 static int config_input(AVFilterLink *inlink)
74 AVFilterContext *ctx = inlink->dst;
75 FieldOrderContext *fieldorder = ctx->priv;
78 /** full an array with the number of bytes that the video
79 * data occupies per line for each plane of the input video */
80 for (plane = 0; plane < 4; plane++) {
81 fieldorder->line_size[plane] = av_image_get_linesize(
90 static AVFrame *get_video_buffer(AVFilterLink *inlink, int w, int h)
92 AVFilterContext *ctx = inlink->dst;
93 AVFilterLink *outlink = ctx->outputs[0];
95 return ff_get_video_buffer(outlink, w, h);
98 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
100 AVFilterContext *ctx = inlink->dst;
101 FieldOrderContext *s = ctx->priv;
102 AVFilterLink *outlink = ctx->outputs[0];
103 int h, plane, line_step, line_size, line;
106 if (!frame->interlaced_frame ||
107 frame->top_field_first == s->dst_tff)
108 return ff_filter_frame(outlink, frame);
111 "picture will move %s one line\n",
112 s->dst_tff ? "up" : "down");
114 for (plane = 0; plane < 4 && frame->data[plane]; plane++) {
115 line_step = frame->linesize[plane];
116 line_size = s->line_size[plane];
117 data = frame->data[plane];
119 /** Move every line up one line, working from
120 * the top to the bottom of the frame.
121 * The original top line is lost.
122 * The new last line is created as a copy of the
123 * penultimate line from that field. */
124 for (line = 0; line < h; line++) {
125 if (1 + line < frame->height) {
126 memcpy(data, data + line_step, line_size);
128 memcpy(data, data - line_step - line_step, line_size);
133 /** Move every line down one line, working from
134 * the bottom to the top of the frame.
135 * The original bottom line is lost.
136 * The new first line is created as a copy of the
137 * second line from that field. */
138 data += (h - 1) * line_step;
139 for (line = h - 1; line >= 0 ; line--) {
141 memcpy(data, data - line_step, line_size);
143 memcpy(data, data + line_step + line_step, line_size);
149 frame->top_field_first = s->dst_tff;
151 return ff_filter_frame(outlink, frame);
154 #define OFFSET(x) offsetof(FieldOrderContext, x)
155 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM
156 static const AVOption options[] = {
157 { "order", "output field order", OFFSET(dst_tff), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, FLAGS, "order" },
158 { "bff", "bottom field first", 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, .unit = "order" },
159 { "tff", "top field first", 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, .unit = "order" },
163 static const AVClass fieldorder_class = {
164 .class_name = "fieldorder",
165 .item_name = av_default_item_name,
167 .version = LIBAVUTIL_VERSION_INT,
170 static const AVFilterPad avfilter_vf_fieldorder_inputs[] = {
173 .type = AVMEDIA_TYPE_VIDEO,
174 .config_props = config_input,
175 .get_video_buffer = get_video_buffer,
176 .filter_frame = filter_frame,
182 static const AVFilterPad avfilter_vf_fieldorder_outputs[] = {
185 .type = AVMEDIA_TYPE_VIDEO,
190 AVFilter avfilter_vf_fieldorder = {
191 .name = "fieldorder",
192 .description = NULL_IF_CONFIG_SMALL("Set the field order."),
193 .priv_size = sizeof(FieldOrderContext),
194 .priv_class = &fieldorder_class,
195 .query_formats = query_formats,
196 .inputs = avfilter_vf_fieldorder_inputs,
197 .outputs = avfilter_vf_fieldorder_outputs,