2 * Copyright (c) 2003 Michael Zucchi <notzed@ximian.com>
3 * Copyright (c) 2010 Baptiste Coudurier
4 * Copyright (c) 2011 Stefano Sabatini
5 * Copyright (c) 2013 Vittorio Giovara <vittorio.giovara@gmail.com>
7 * This file is part of FFmpeg.
9 * FFmpeg is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License along
20 * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
21 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
26 * progressive to interlaced content filter, inspired by heavy debugging of tinterlace filter
29 #include "libavutil/common.h"
30 #include "libavutil/opt.h"
31 #include "libavutil/imgutils.h"
32 #include "libavutil/avassert.h"
49 typedef struct InterlaceContext
{
51 enum ScanMode scan
; // top or bottom field first scanning
52 int lowpass
; // enable or disable low pass filterning
53 AVFrame
*cur
, *next
; // the two frames from which the new one is obtained
56 #define OFFSET(x) offsetof(InterlaceContext, x)
57 #define V AV_OPT_FLAG_VIDEO_PARAM
58 static const AVOption interlace_options
[] = {
59 { "scan", "scanning mode", OFFSET(scan
),
60 AV_OPT_TYPE_INT
, {.i64
= MODE_TFF
}, 0, 1, .flags
= V
, .unit
= "scan" },
61 { "tff", "top field first", 0,
62 AV_OPT_TYPE_CONST
, {.i64
= MODE_TFF
}, INT_MIN
, INT_MAX
, .flags
= V
, .unit
= "scan" },
63 { "bff", "bottom field first", 0,
64 AV_OPT_TYPE_CONST
, {.i64
= MODE_BFF
}, INT_MIN
, INT_MAX
, .flags
= V
, .unit
= "scan" },
65 { "lowpass", "enable vertical low-pass filter", OFFSET(lowpass
),
66 AV_OPT_TYPE_INT
, {.i64
= 1 }, 0, 1, .flags
= V
},
70 AVFILTER_DEFINE_CLASS(interlace
);
72 static const enum AVPixelFormat formats_supported
[] = {
73 AV_PIX_FMT_YUV420P
, AV_PIX_FMT_YUV422P
, AV_PIX_FMT_YUV444P
,
74 AV_PIX_FMT_YUV444P
, AV_PIX_FMT_YUV410P
, AV_PIX_FMT_YUVA420P
,
75 AV_PIX_FMT_GRAY8
, AV_PIX_FMT_YUVJ420P
, AV_PIX_FMT_YUVJ422P
,
76 AV_PIX_FMT_YUVJ444P
, AV_PIX_FMT_YUVJ440P
, AV_PIX_FMT_NONE
79 static int query_formats(AVFilterContext
*ctx
)
81 ff_set_common_formats(ctx
, ff_make_format_list(formats_supported
));
85 static av_cold
void uninit(AVFilterContext
*ctx
)
87 InterlaceContext
*s
= ctx
->priv
;
89 av_frame_free(&s
->cur
);
90 av_frame_free(&s
->next
);
93 static int config_out_props(AVFilterLink
*outlink
)
95 AVFilterContext
*ctx
= outlink
->src
;
96 AVFilterLink
*inlink
= outlink
->src
->inputs
[0];
97 InterlaceContext
*s
= ctx
->priv
;
100 av_log(ctx
, AV_LOG_ERROR
, "input video height is too small\n");
101 return AVERROR_INVALIDDATA
;
105 av_log(ctx
, AV_LOG_WARNING
, "***warning*** Lowpass filter is disabled, "
106 "the resulting video will be aliased rather than interlaced.\n");
109 outlink
->w
= inlink
->w
;
110 outlink
->h
= inlink
->h
;
111 outlink
->time_base
= inlink
->time_base
;
112 outlink
->frame_rate
= inlink
->frame_rate
;
114 outlink
->time_base
.num
*= 2;
115 outlink
->frame_rate
.den
*= 2;
116 outlink
->flags
|= FF_LINK_FLAG_REQUEST_LOOP
;
118 av_log(ctx
, AV_LOG_VERBOSE
, "%s interlacing %s lowpass filter\n",
119 s
->scan
== MODE_TFF
? "tff" : "bff", (s
->lowpass
) ? "with" : "without");
124 static void copy_picture_field(AVFrame
*src_frame
, AVFrame
*dst_frame
,
125 AVFilterLink
*inlink
, enum FieldType field_type
,
128 const AVPixFmtDescriptor
*desc
= av_pix_fmt_desc_get(inlink
->format
);
129 int vsub
= desc
->log2_chroma_h
;
132 for (plane
= 0; plane
< desc
->nb_components
; plane
++) {
133 int lines
= (plane
== 1 || plane
== 2) ? FF_CEIL_RSHIFT(inlink
->h
, vsub
) : inlink
->h
;
134 int linesize
= av_image_get_linesize(inlink
->format
, inlink
->w
, plane
);
135 uint8_t *dstp
= dst_frame
->data
[plane
];
136 const uint8_t *srcp
= src_frame
->data
[plane
];
138 av_assert0(linesize
>= 0);
140 lines
= (lines
+ (field_type
== FIELD_UPPER
)) / 2;
141 if (field_type
== FIELD_LOWER
)
142 srcp
+= src_frame
->linesize
[plane
];
143 if (field_type
== FIELD_LOWER
)
144 dstp
+= dst_frame
->linesize
[plane
];
146 int srcp_linesize
= src_frame
->linesize
[plane
] * 2;
147 int dstp_linesize
= dst_frame
->linesize
[plane
] * 2;
148 for (j
= lines
; j
> 0; j
--) {
149 const uint8_t *srcp_above
= srcp
- src_frame
->linesize
[plane
];
150 const uint8_t *srcp_below
= srcp
+ src_frame
->linesize
[plane
];
152 srcp_above
= srcp
; // there is no line above
154 srcp_below
= srcp
; // there is no line below
155 for (i
= 0; i
< linesize
; i
++) {
156 // this calculation is an integer representation of
157 // '0.5 * current + 0.25 * above + 0.25 * below'
158 // '1 +' is for rounding.
159 dstp
[i
] = (1 + srcp
[i
] + srcp
[i
] + srcp_above
[i
] + srcp_below
[i
]) >> 2;
161 dstp
+= dstp_linesize
;
162 srcp
+= srcp_linesize
;
165 av_image_copy_plane(dstp
, dst_frame
->linesize
[plane
] * 2,
166 srcp
, src_frame
->linesize
[plane
] * 2,
172 static int filter_frame(AVFilterLink
*inlink
, AVFrame
*buf
)
174 AVFilterContext
*ctx
= inlink
->dst
;
175 AVFilterLink
*outlink
= ctx
->outputs
[0];
176 InterlaceContext
*s
= ctx
->priv
;
180 av_frame_free(&s
->cur
);
184 /* we need at least two frames */
185 if (!s
->cur
|| !s
->next
)
188 if (s
->cur
->interlaced_frame
) {
189 av_log(ctx
, AV_LOG_WARNING
,
190 "video is already interlaced, adjusting framerate only\n");
191 out
= av_frame_clone(s
->cur
);
193 return AVERROR(ENOMEM
);
194 out
->pts
/= 2; // adjust pts to new framerate
195 ret
= ff_filter_frame(outlink
, out
);
199 tff
= (s
->scan
== MODE_TFF
);
200 out
= ff_get_video_buffer(outlink
, outlink
->w
, outlink
->h
);
202 return AVERROR(ENOMEM
);
204 av_frame_copy_props(out
, s
->cur
);
205 out
->interlaced_frame
= 1;
206 out
->top_field_first
= tff
;
207 out
->pts
/= 2; // adjust pts to new framerate
209 /* copy upper/lower field from cur */
210 copy_picture_field(s
->cur
, out
, inlink
, tff
? FIELD_UPPER
: FIELD_LOWER
, s
->lowpass
);
211 av_frame_free(&s
->cur
);
213 /* copy lower/upper field from next */
214 copy_picture_field(s
->next
, out
, inlink
, tff
? FIELD_LOWER
: FIELD_UPPER
, s
->lowpass
);
215 av_frame_free(&s
->next
);
217 ret
= ff_filter_frame(outlink
, out
);
222 static const AVFilterPad inputs
[] = {
225 .type
= AVMEDIA_TYPE_VIDEO
,
226 .filter_frame
= filter_frame
,
231 static const AVFilterPad outputs
[] = {
234 .type
= AVMEDIA_TYPE_VIDEO
,
235 .config_props
= config_out_props
,
240 AVFilter ff_vf_interlace
= {
242 .description
= NULL_IF_CONFIG_SMALL("Convert progressive video into interlaced."),
244 .priv_class
= &interlace_class
,
245 .priv_size
= sizeof(InterlaceContext
),
246 .query_formats
= query_formats
,