2 * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
4 * FFmpeg is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * FFmpeg is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21 * Motion Compensation Deinterlacer
22 * Ported from MPlayer libmpcodecs/vf_mcdeint.c.
26 * The motion estimation is somewhat at the mercy of the input, if the
27 * input frames are created purely based on spatial interpolation then
28 * for example a thin black line or another random and not
29 * interpolateable pattern will cause problems.
30 * Note: completely ignoring the "unavailable" lines during motion
31 * estimation did not look any better, so the most obvious solution
32 * would be to improve tfields or penalize problematic motion vectors.
34 * If non iterative ME is used then snow currently ignores the OBMC
35 * window and as a result sometimes creates artifacts.
37 * Only past frames are used, we should ideally use future frames too,
38 * something like filtering the whole movie in forward and then
39 * backward direction seems like a interesting idea but the current
40 * filter framework is FAR from supporting such things.
42 * Combining the motion compensated image with the input image also is
43 * not as trivial as it seems, simple blindly taking even lines from
44 * one and odd ones from the other does not work at all as ME/MC
45 * sometimes has nothing in the previous frames which matches the
46 * current. The current algorithm has been found by trial and error
47 * and almost certainly can be improved...
50 #include "libavutil/opt.h"
51 #include "libavutil/pixdesc.h"
52 #include "libavcodec/avcodec.h"
66 PARITY_TFF = 0, ///< top field first
67 PARITY_BFF = 1, ///< bottom field first
72 enum MCDeintMode mode;
73 enum MCDeintParity parity;
75 AVCodecContext *enc_ctx;
78 #define OFFSET(x) offsetof(MCDeintContext, x)
79 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
80 #define CONST(name, help, val, unit) { name, help, 0, AV_OPT_TYPE_CONST, {.i64=val}, INT_MIN, INT_MAX, FLAGS, unit }
82 static const AVOption mcdeint_options[] = {
83 { "mode", "set mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=MODE_FAST}, 0, MODE_NB-1, FLAGS, .unit="mode" },
84 CONST("fast", NULL, MODE_FAST, "mode"),
85 CONST("medium", NULL, MODE_MEDIUM, "mode"),
86 CONST("slow", NULL, MODE_SLOW, "mode"),
87 CONST("extra_slow", NULL, MODE_EXTRA_SLOW, "mode"),
89 { "parity", "set the assumed picture field parity", OFFSET(parity), AV_OPT_TYPE_INT, {.i64=PARITY_BFF}, -1, 1, FLAGS, "parity" },
90 CONST("tff", "assume top field first", PARITY_TFF, "parity"),
91 CONST("bff", "assume bottom field first", PARITY_BFF, "parity"),
93 { "qp", "set qp", OFFSET(qp), AV_OPT_TYPE_INT, {.i64=1}, INT_MIN, INT_MAX, FLAGS },
97 AVFILTER_DEFINE_CLASS(mcdeint);
99 static int config_props(AVFilterLink *inlink)
101 AVFilterContext *ctx = inlink->dst;
102 MCDeintContext *mcdeint = ctx->priv;
104 AVCodecContext *enc_ctx;
105 AVDictionary *opts = NULL;
108 if (!(enc = avcodec_find_encoder(AV_CODEC_ID_SNOW))) {
109 av_log(ctx, AV_LOG_ERROR, "Snow encoder is not enabled in libavcodec\n");
110 return AVERROR(EINVAL);
113 mcdeint->enc_ctx = avcodec_alloc_context3(enc);
114 if (!mcdeint->enc_ctx)
115 return AVERROR(ENOMEM);
116 enc_ctx = mcdeint->enc_ctx;
117 enc_ctx->width = inlink->w;
118 enc_ctx->height = inlink->h;
119 enc_ctx->time_base = (AVRational){1,25}; // meaningless
120 enc_ctx->gop_size = INT_MAX;
121 enc_ctx->max_b_frames = 0;
122 enc_ctx->pix_fmt = AV_PIX_FMT_YUV420P;
123 enc_ctx->flags = CODEC_FLAG_QSCALE | CODEC_FLAG_LOW_DELAY;
124 enc_ctx->strict_std_compliance = FF_COMPLIANCE_EXPERIMENTAL;
125 enc_ctx->global_quality = 1;
126 enc_ctx->me_cmp = enc_ctx->me_sub_cmp = FF_CMP_SAD;
127 enc_ctx->mb_cmp = FF_CMP_SSE;
128 av_dict_set(&opts, "memc_only", "1", 0);
130 switch (mcdeint->mode) {
131 case MODE_EXTRA_SLOW:
134 enc_ctx->me_method = ME_ITER;
136 enc_ctx->flags |= CODEC_FLAG_4MV;
137 enc_ctx->dia_size = 2;
139 enc_ctx->flags |= CODEC_FLAG_QPEL;
142 ret = avcodec_open2(enc_ctx, enc, &opts);
150 static av_cold void uninit(AVFilterContext *ctx)
152 MCDeintContext *mcdeint = ctx->priv;
154 if (mcdeint->enc_ctx) {
155 avcodec_close(mcdeint->enc_ctx);
156 av_freep(&mcdeint->enc_ctx);
160 static int query_formats(AVFilterContext *ctx)
162 static const enum PixelFormat pix_fmts[] = {
163 AV_PIX_FMT_YUV420P, AV_PIX_FMT_NONE
166 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
171 static int filter_frame(AVFilterLink *inlink, AVFrame *inpic)
173 MCDeintContext *mcdeint = inlink->dst->priv;
174 AVFilterLink *outlink = inlink->dst->outputs[0];
175 AVFrame *outpic, *frame_dec;
177 int x, y, i, ret, got_frame = 0;
179 outpic = ff_get_video_buffer(outlink, outlink->w, outlink->h);
181 av_frame_free(&inpic);
182 return AVERROR(ENOMEM);
184 av_frame_copy_props(outpic, inpic);
185 inpic->quality = mcdeint->qp * FF_QP2LAMBDA;
187 av_init_packet(&pkt);
188 pkt.data = NULL; // packet data will be allocated by the encoder
191 ret = avcodec_encode_video2(mcdeint->enc_ctx, &pkt, inpic, &got_frame);
195 frame_dec = mcdeint->enc_ctx->coded_frame;
197 for (i = 0; i < 3; i++) {
199 int w = FF_CEIL_RSHIFT(inlink->w, is_chroma);
200 int h = FF_CEIL_RSHIFT(inlink->h, is_chroma);
201 int fils = frame_dec->linesize[i];
202 int srcs = inpic ->linesize[i];
203 int dsts = outpic ->linesize[i];
205 for (y = 0; y < h; y++) {
206 if ((y ^ mcdeint->parity) & 1) {
207 for (x = 0; x < w; x++) {
208 uint8_t *filp = &frame_dec->data[i][x + y*fils];
209 uint8_t *srcp = &inpic ->data[i][x + y*srcs];
210 uint8_t *dstp = &outpic ->data[i][x + y*dsts];
212 if (y > 0 && y < h-1){
213 int is_edge = x < 3 || x > w-4;
214 int diff0 = filp[-fils] - srcp[-srcs];
215 int diff1 = filp[+fils] - srcp[+srcs];
218 #define DELTA(j) av_clip(j, -x, w-1-x)
220 #define GET_SCORE_EDGE(j)\
221 FFABS(srcp[-srcs+DELTA(-1+(j))] - srcp[+srcs+DELTA(-1-(j))])+\
222 FFABS(srcp[-srcs+DELTA(j) ] - srcp[+srcs+DELTA( -(j))])+\
223 FFABS(srcp[-srcs+DELTA(1+(j)) ] - srcp[+srcs+DELTA( 1-(j))])
225 #define GET_SCORE(j)\
226 FFABS(srcp[-srcs-1+(j)] - srcp[+srcs-1-(j)])+\
227 FFABS(srcp[-srcs +(j)] - srcp[+srcs -(j)])+\
228 FFABS(srcp[-srcs+1+(j)] - srcp[+srcs+1-(j)])
230 #define CHECK_EDGE(j)\
231 { int score = GET_SCORE_EDGE(j);\
232 if (score < spatial_score){\
233 spatial_score = score;\
234 diff0 = filp[-fils+DELTA(j)] - srcp[-srcs+DELTA(j)];\
235 diff1 = filp[+fils+DELTA(-(j))] - srcp[+srcs+DELTA(-(j))];\
238 { int score = GET_SCORE(j);\
239 if (score < spatial_score){\
240 spatial_score= score;\
241 diff0 = filp[-fils+(j)] - srcp[-srcs+(j)];\
242 diff1 = filp[+fils-(j)] - srcp[+srcs-(j)];\
245 int spatial_score = GET_SCORE_EDGE(0) - 1;
246 CHECK_EDGE(-1) CHECK_EDGE(-2) }} }}
247 CHECK_EDGE( 1) CHECK_EDGE( 2) }} }}
249 int spatial_score = GET_SCORE(0) - 1;
250 CHECK(-1) CHECK(-2) }} }}
251 CHECK( 1) CHECK( 2) }} }}
255 if (diff0 + diff1 > 0)
256 temp -= (diff0 + diff1 - FFABS(FFABS(diff0) - FFABS(diff1)) / 2) / 2;
258 temp -= (diff0 + diff1 + FFABS(FFABS(diff0) - FFABS(diff1)) / 2) / 2;
259 *filp = *dstp = temp > 255U ? ~(temp>>31) : temp;
267 for (y = 0; y < h; y++) {
268 if (!((y ^ mcdeint->parity) & 1)) {
269 for (x = 0; x < w; x++) {
270 frame_dec->data[i][x + y*fils] =
271 outpic ->data[i][x + y*dsts] = inpic->data[i][x + y*srcs];
276 mcdeint->parity ^= 1;
279 av_free_packet(&pkt);
280 av_frame_free(&inpic);
282 av_frame_free(&outpic);
285 return ff_filter_frame(outlink, outpic);
288 static const AVFilterPad mcdeint_inputs[] = {
291 .type = AVMEDIA_TYPE_VIDEO,
292 .filter_frame = filter_frame,
293 .config_props = config_props,
298 static const AVFilterPad mcdeint_outputs[] = {
301 .type = AVMEDIA_TYPE_VIDEO,
306 AVFilter ff_vf_mcdeint = {
308 .description = NULL_IF_CONFIG_SMALL("Apply motion compensating deinterlacing."),
309 .priv_size = sizeof(MCDeintContext),
311 .query_formats = query_formats,
312 .inputs = mcdeint_inputs,
313 .outputs = mcdeint_outputs,
314 .priv_class = &mcdeint_class,