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
);
105 av_log(ctx
, AV_LOG_TRACE
,
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
,