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"
52 enum ScanMode scan; // top or bottom field first scanning
53 #if FF_API_INTERLACE_LOWPASS_SET
54 int lowpass; // enable or disable low pass filterning
56 AVFrame *cur, *next; // the two frames from which the new one is obtained
59 #define OFFSET(x) offsetof(InterlaceContext, x)
60 #define V AV_OPT_FLAG_VIDEO_PARAM
61 static const AVOption interlace_options[] = {
62 { "scan", "scanning mode", OFFSET(scan),
63 AV_OPT_TYPE_INT, {.i64 = MODE_TFF }, 0, 1, .flags = V, .unit = "scan" },
64 { "tff", "top field first", 0,
65 AV_OPT_TYPE_CONST, {.i64 = MODE_TFF }, INT_MIN, INT_MAX, .flags = V, .unit = "scan" },
66 { "bff", "bottom field first", 0,
67 AV_OPT_TYPE_CONST, {.i64 = MODE_BFF }, INT_MIN, INT_MAX, .flags = V, .unit = "scan" },
68 #if FF_API_INTERLACE_LOWPASS_SET
69 { "lowpass", "(deprecated, this option is always set)", OFFSET(lowpass),
70 AV_OPT_TYPE_INT, {.i64 = 1 }, 0, 1, .flags = V },
75 AVFILTER_DEFINE_CLASS(interlace);
77 static const enum AVPixelFormat formats_supported[] = {
78 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV444P,
79 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUVA420P,
80 AV_PIX_FMT_GRAY8, AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P,
81 AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P, AV_PIX_FMT_NONE
84 static int query_formats(AVFilterContext *ctx)
86 ff_set_common_formats(ctx, ff_make_format_list(formats_supported));
90 static av_cold void uninit(AVFilterContext *ctx)
92 InterlaceContext *s = ctx->priv;
94 av_frame_free(&s->cur);
95 av_frame_free(&s->next);
98 static int config_out_props(AVFilterLink *outlink)
100 AVFilterContext *ctx = outlink->src;
101 AVFilterLink *inlink = outlink->src->inputs[0];
102 InterlaceContext *s = ctx->priv;
104 #if FF_API_INTERLACE_LOWPASS_SET
106 av_log(ctx, AV_LOG_WARNING, "This option is deprecated and always set.\n");
110 av_log(ctx, AV_LOG_ERROR, "input video height is too small\n");
111 return AVERROR_INVALIDDATA;
114 outlink->w = inlink->w;
115 outlink->h = inlink->h;
116 outlink->time_base = inlink->time_base;
117 outlink->frame_rate = inlink->frame_rate;
119 outlink->time_base.num *= 2;
120 outlink->frame_rate.den *= 2;
121 outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP;
123 av_log(ctx, AV_LOG_VERBOSE, "%s interlacing\n",
124 s->scan == MODE_TFF ? "tff" : "bff");
129 static void copy_picture_field(AVFrame *src_frame, AVFrame *dst_frame,
130 AVFilterLink *inlink, enum FieldType field_type)
132 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
133 int vsub = desc->log2_chroma_h;
136 for (plane = 0; plane < desc->nb_components; plane++) {
137 int lines = (plane == 1 || plane == 2) ? FF_CEIL_RSHIFT(inlink->h, vsub) : inlink->h;
138 int linesize = av_image_get_linesize(inlink->format, inlink->w, plane);
139 uint8_t *dstp = dst_frame->data[plane];
140 const uint8_t *srcp = src_frame->data[plane];
144 av_assert0(linesize >= 0);
146 lines = (lines + (field_type == FIELD_UPPER)) / 2;
147 if (field_type == FIELD_LOWER)
148 srcp += src_frame->linesize[plane];
149 if (field_type == FIELD_LOWER)
150 dstp += dst_frame->linesize[plane];
152 srcp_linesize = src_frame->linesize[plane] * 2;
153 dstp_linesize = dst_frame->linesize[plane] * 2;
154 for (j = lines; j > 0; j--) {
155 const uint8_t *srcp_above = srcp - src_frame->linesize[plane];
156 const uint8_t *srcp_below = srcp + src_frame->linesize[plane];
158 srcp_above = srcp; // there is no line above
160 srcp_below = srcp; // there is no line below
161 for (i = 0; i < linesize; i++) {
162 // this calculation is an integer representation of
163 // '0.5 * current + 0.25 * above + 0.25 * below'
164 // '1 +' is for rounding.
165 dstp[i] = (1 + srcp[i] + srcp[i] + srcp_above[i] + srcp_below[i]) >> 2;
167 dstp += dstp_linesize;
168 srcp += srcp_linesize;
173 static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
175 AVFilterContext *ctx = inlink->dst;
176 AVFilterLink *outlink = ctx->outputs[0];
177 InterlaceContext *s = ctx->priv;
181 av_frame_free(&s->cur);
185 /* we need at least two frames */
186 if (!s->cur || !s->next)
189 if (s->cur->interlaced_frame) {
190 av_log(ctx, AV_LOG_WARNING,
191 "video is already interlaced, adjusting framerate only\n");
192 out = av_frame_clone(s->cur);
194 return AVERROR(ENOMEM);
195 out->pts /= 2; // adjust pts to new framerate
196 ret = ff_filter_frame(outlink, out);
200 tff = (s->scan == MODE_TFF);
201 out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
203 return AVERROR(ENOMEM);
205 av_frame_copy_props(out, s->cur);
206 out->interlaced_frame = 1;
207 out->top_field_first = tff;
208 out->pts /= 2; // adjust pts to new framerate
210 /* copy upper/lower field from cur */
211 copy_picture_field(s->cur, out, inlink, tff ? FIELD_UPPER : FIELD_LOWER);
212 av_frame_free(&s->cur);
214 /* copy lower/upper field from next */
215 copy_picture_field(s->next, out, inlink, tff ? FIELD_LOWER : FIELD_UPPER);
216 av_frame_free(&s->next);
218 ret = ff_filter_frame(outlink, out);
223 static const AVFilterPad inputs[] = {
226 .type = AVMEDIA_TYPE_VIDEO,
227 .filter_frame = filter_frame,
232 static const AVFilterPad outputs[] = {
235 .type = AVMEDIA_TYPE_VIDEO,
236 .config_props = config_out_props,
241 AVFilter ff_vf_interlace = {
243 .description = NULL_IF_CONFIG_SMALL("Convert progressive video into interlaced."),
245 .priv_class = &interlace_class,
246 .priv_size = sizeof(InterlaceContext),
247 .query_formats = query_formats,