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"
38 typedef struct FieldOrderContext {
40 int dst_tff; ///< output bff/tff
41 int line_size[4]; ///< bytes of pixel data per line for each plane
44 static int query_formats(AVFilterContext *ctx)
46 AVFilterFormats *formats;
47 enum AVPixelFormat pix_fmt;
50 /** accept any input pixel format that is not hardware accelerated, not
51 * a bitstream format, and does not have vertically sub-sampled chroma */
53 const AVPixFmtDescriptor *desc = NULL;
55 while ((desc = av_pix_fmt_desc_next(desc))) {
56 pix_fmt = av_pix_fmt_desc_get_id(desc);
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 *s = 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 s->line_size[plane] = av_image_get_linesize(inlink->format, inlink->w,
88 static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
90 AVFilterContext *ctx = inlink->dst;
91 FieldOrderContext *s = ctx->priv;
92 AVFilterLink *outlink = ctx->outputs[0];
93 int h, plane, line_step, line_size, line;
96 if (!frame->interlaced_frame ||
97 frame->top_field_first == s->dst_tff) {
98 av_log(ctx, AV_LOG_VERBOSE,
100 frame->interlaced_frame ?
101 "frame with same field order" : "progressive frame");
102 return ff_filter_frame(outlink, frame);
106 "picture will move %s one line\n",
107 s->dst_tff ? "up" : "down");
109 for (plane = 0; plane < 4 && frame->data[plane]; plane++) {
110 line_step = frame->linesize[plane];
111 line_size = s->line_size[plane];
112 data = frame->data[plane];
114 /** Move every line up one line, working from
115 * the top to the bottom of the frame.
116 * The original top line is lost.
117 * The new last line is created as a copy of the
118 * penultimate line from that field. */
119 for (line = 0; line < h; line++) {
120 if (1 + line < frame->height) {
121 memcpy(data, data + line_step, line_size);
123 memcpy(data, data - line_step - line_step, line_size);
128 /** Move every line down one line, working from
129 * the bottom to the top of the frame.
130 * The original bottom line is lost.
131 * The new first line is created as a copy of the
132 * second line from that field. */
133 data += (h - 1) * line_step;
134 for (line = h - 1; line >= 0 ; line--) {
136 memcpy(data, data - line_step, line_size);
138 memcpy(data, data + line_step + line_step, line_size);
144 frame->top_field_first = s->dst_tff;
146 return ff_filter_frame(outlink, frame);
149 #define OFFSET(x) offsetof(FieldOrderContext, x)
150 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM
151 static const AVOption options[] = {
152 { "order", "output field order", OFFSET(dst_tff), AV_OPT_TYPE_INT, { .i64 = 1 }, 0, 1, FLAGS, "order" },
153 { "bff", "bottom field first", 0, AV_OPT_TYPE_CONST, { .i64 = 0 }, .unit = "order" },
154 { "tff", "top field first", 0, AV_OPT_TYPE_CONST, { .i64 = 1 }, .unit = "order" },
158 static const AVClass fieldorder_class = {
159 .class_name = "fieldorder",
160 .item_name = av_default_item_name,
162 .version = LIBAVUTIL_VERSION_INT,
165 static const AVFilterPad avfilter_vf_fieldorder_inputs[] = {
168 .type = AVMEDIA_TYPE_VIDEO,
169 .config_props = config_input,
170 .filter_frame = filter_frame,
176 static const AVFilterPad avfilter_vf_fieldorder_outputs[] = {
179 .type = AVMEDIA_TYPE_VIDEO,
184 AVFilter ff_vf_fieldorder = {
185 .name = "fieldorder",
186 .description = NULL_IF_CONFIG_SMALL("Set the field order."),
187 .priv_size = sizeof(FieldOrderContext),
188 .priv_class = &fieldorder_class,
189 .query_formats = query_formats,
190 .inputs = avfilter_vf_fieldorder_inputs,
191 .outputs = avfilter_vf_fieldorder_outputs,