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"
36 #include "interlace.h"
40 #define OFFSET(x) offsetof(InterlaceContext, x)
41 #define V AV_OPT_FLAG_VIDEO_PARAM
42 static const AVOption interlace_options[] = {
43 { "scan", "scanning mode", OFFSET(scan),
44 AV_OPT_TYPE_INT, {.i64 = MODE_TFF }, 0, 1, .flags = V, .unit = "scan" },
45 { "tff", "top field first", 0,
46 AV_OPT_TYPE_CONST, {.i64 = MODE_TFF }, INT_MIN, INT_MAX, .flags = V, .unit = "scan" },
47 { "bff", "bottom field first", 0,
48 AV_OPT_TYPE_CONST, {.i64 = MODE_BFF }, INT_MIN, INT_MAX, .flags = V, .unit = "scan" },
49 { "lowpass", "enable vertical low-pass filter", OFFSET(lowpass),
50 AV_OPT_TYPE_INT, {.i64 = 1 }, 0, 1, .flags = V },
54 AVFILTER_DEFINE_CLASS(interlace);
56 static void lowpass_line_c(uint8_t *dstp, ptrdiff_t linesize,
58 const uint8_t *srcp_above,
59 const uint8_t *srcp_below)
62 for (i = 0; i < linesize; i++) {
63 // this calculation is an integer representation of
64 // '0.5 * current + 0.25 * above + 0.25 * below'
65 // '1 +' is for rounding.
66 dstp[i] = (1 + srcp[i] + srcp[i] + srcp_above[i] + srcp_below[i]) >> 2;
70 static const enum AVPixelFormat formats_supported[] = {
71 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUV444P,
72 AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUVA420P,
73 AV_PIX_FMT_GRAY8, AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P,
74 AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P, AV_PIX_FMT_NONE
77 static int query_formats(AVFilterContext *ctx)
79 ff_set_common_formats(ctx, ff_make_format_list(formats_supported));
83 static av_cold void uninit(AVFilterContext *ctx)
85 InterlaceContext *s = ctx->priv;
87 av_frame_free(&s->cur);
88 av_frame_free(&s->next);
91 static int config_out_props(AVFilterLink *outlink)
93 AVFilterContext *ctx = outlink->src;
94 AVFilterLink *inlink = outlink->src->inputs[0];
95 InterlaceContext *s = ctx->priv;
98 av_log(ctx, AV_LOG_ERROR, "input video height is too small\n");
99 return AVERROR_INVALIDDATA;
103 av_log(ctx, AV_LOG_WARNING, "Lowpass filter is disabled, "
104 "the resulting video will be aliased rather than interlaced.\n");
107 outlink->w = inlink->w;
108 outlink->h = inlink->h;
109 outlink->time_base = inlink->time_base;
110 outlink->frame_rate = inlink->frame_rate;
112 outlink->time_base.num *= 2;
113 outlink->frame_rate.den *= 2;
114 outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP;
118 s->lowpass_line = lowpass_line_c;
120 ff_interlace_init_x86(s);
123 av_log(ctx, AV_LOG_VERBOSE, "%s interlacing %s lowpass filter\n",
124 s->scan == MODE_TFF ? "tff" : "bff", (s->lowpass) ? "with" : "without");
129 static void copy_picture_field(InterlaceContext *s,
130 AVFrame *src_frame, AVFrame *dst_frame,
131 AVFilterLink *inlink, enum FieldType field_type,
134 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
135 int hsub = desc->log2_chroma_w;
136 int vsub = desc->log2_chroma_h;
139 for (plane = 0; plane < desc->nb_components; plane++) {
140 int cols = (plane == 1 || plane == 2) ? -(-inlink->w) >> hsub : inlink->w;
141 int lines = (plane == 1 || plane == 2) ? FF_CEIL_RSHIFT(inlink->h, vsub) : inlink->h;
142 uint8_t *dstp = dst_frame->data[plane];
143 const uint8_t *srcp = src_frame->data[plane];
145 av_assert0(cols >= 0 || lines >= 0);
147 lines = (lines + (field_type == FIELD_UPPER)) / 2;
148 if (field_type == FIELD_LOWER) {
149 srcp += src_frame->linesize[plane];
150 dstp += dst_frame->linesize[plane];
153 int srcp_linesize = src_frame->linesize[plane] * 2;
154 int dstp_linesize = dst_frame->linesize[plane] * 2;
155 for (j = lines; j > 0; j--) {
156 const uint8_t *srcp_above = srcp - src_frame->linesize[plane];
157 const uint8_t *srcp_below = srcp + src_frame->linesize[plane];
159 srcp_above = srcp; // there is no line above
161 srcp_below = srcp; // there is no line below
162 s->lowpass_line(dstp, cols, srcp, srcp_above, srcp_below);
163 dstp += dstp_linesize;
164 srcp += srcp_linesize;
167 av_image_copy_plane(dstp, dst_frame->linesize[plane] * 2,
168 srcp, src_frame->linesize[plane] * 2,
174 static int filter_frame(AVFilterLink *inlink, AVFrame *buf)
176 AVFilterContext *ctx = inlink->dst;
177 AVFilterLink *outlink = ctx->outputs[0];
178 InterlaceContext *s = ctx->priv;
182 av_frame_free(&s->cur);
186 /* we need at least two frames */
187 if (!s->cur || !s->next)
190 if (s->cur->interlaced_frame) {
191 av_log(ctx, AV_LOG_WARNING,
192 "video is already interlaced, adjusting framerate only\n");
193 out = av_frame_clone(s->cur);
195 return AVERROR(ENOMEM);
196 out->pts /= 2; // adjust pts to new framerate
197 ret = ff_filter_frame(outlink, out);
201 tff = (s->scan == MODE_TFF);
202 out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
204 return AVERROR(ENOMEM);
206 av_frame_copy_props(out, s->cur);
207 out->interlaced_frame = 1;
208 out->top_field_first = tff;
209 out->pts /= 2; // adjust pts to new framerate
211 /* copy upper/lower field from cur */
212 copy_picture_field(s, s->cur, out, inlink, tff ? FIELD_UPPER : FIELD_LOWER, s->lowpass);
213 av_frame_free(&s->cur);
215 /* copy lower/upper field from next */
216 copy_picture_field(s, s->next, out, inlink, tff ? FIELD_LOWER : FIELD_UPPER, s->lowpass);
217 av_frame_free(&s->next);
219 ret = ff_filter_frame(outlink, out);
224 static const AVFilterPad inputs[] = {
227 .type = AVMEDIA_TYPE_VIDEO,
228 .filter_frame = filter_frame,
233 static const AVFilterPad outputs[] = {
236 .type = AVMEDIA_TYPE_VIDEO,
237 .config_props = config_out_props,
242 AVFilter ff_vf_interlace = {
244 .description = NULL_IF_CONFIG_SMALL("Convert progressive video into interlaced."),
246 .priv_class = &interlace_class,
247 .priv_size = sizeof(InterlaceContext),
248 .query_formats = query_formats,