2 * Copyright (c) 2011 Stefano Sabatini
3 * Copyright (c) 2010 Baptiste Coudurier
4 * Copyright (c) 2003 Michael Zucchi <notzed@ximian.com>
6 * This file is part of FFmpeg.
8 * FFmpeg is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with FFmpeg if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
25 * temporal field interlace filter, ported from MPlayer/libmpcodecs
28 #include "libavutil/opt.h"
29 #include "libavutil/imgutils.h"
30 #include "libavutil/avassert.h"
40 MODE_INTERLEAVE_BOTTOM,
47 enum TInterlaceMode mode; ///< interlace mode selected
48 int flags; ///< flags affecting interlacing algorithm
49 int frame; ///< number of the output frame
50 int vsub; ///< chroma vertical subsampling
53 uint8_t *black_data[4]; ///< buffer used to fill padded lines
54 int black_linesize[4];
57 #define OFFSET(x) offsetof(TInterlaceContext, x)
58 #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
59 #define TINTERLACE_FLAG_VLPF 01
61 static const AVOption tinterlace_options[] = {
62 {"mode", "select interlace mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=MODE_MERGE}, 0, MODE_NB-1, FLAGS, "mode"},
63 {"merge", "merge fields", 0, AV_OPT_TYPE_CONST, {.i64=MODE_MERGE}, INT_MIN, INT_MAX, FLAGS, "mode"},
64 {"drop_even", "drop even fields", 0, AV_OPT_TYPE_CONST, {.i64=MODE_DROP_EVEN}, INT_MIN, INT_MAX, FLAGS, "mode"},
65 {"drop_odd", "drop odd fields", 0, AV_OPT_TYPE_CONST, {.i64=MODE_DROP_ODD}, INT_MIN, INT_MAX, FLAGS, "mode"},
66 {"pad", "pad alternate lines with black", 0, AV_OPT_TYPE_CONST, {.i64=MODE_PAD}, INT_MIN, INT_MAX, FLAGS, "mode"},
67 {"interleave_top", "interleave top and bottom fields", 0, AV_OPT_TYPE_CONST, {.i64=MODE_INTERLEAVE_TOP}, INT_MIN, INT_MAX, FLAGS, "mode"},
68 {"interleave_bottom", "interleave bottom and top fields", 0, AV_OPT_TYPE_CONST, {.i64=MODE_INTERLEAVE_BOTTOM}, INT_MIN, INT_MAX, FLAGS, "mode"},
69 {"interlacex2", "interlace fields from two consecutive frames", 0, AV_OPT_TYPE_CONST, {.i64=MODE_INTERLACEX2}, INT_MIN, INT_MAX, FLAGS, "mode"},
71 {"flags", "set flags", OFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0}, 0, INT_MAX, 0, "flags" },
72 {"low_pass_filter", "enable vertical low-pass filter", 0, AV_OPT_TYPE_CONST, {.i64 = TINTERLACE_FLAG_VLPF}, INT_MIN, INT_MAX, FLAGS, "flags" },
73 {"vlpf", "enable vertical low-pass filter", 0, AV_OPT_TYPE_CONST, {.i64 = TINTERLACE_FLAG_VLPF}, INT_MIN, INT_MAX, FLAGS, "flags" },
78 AVFILTER_DEFINE_CLASS(tinterlace);
80 #define FULL_SCALE_YUVJ_FORMATS \
81 AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P
83 static const enum AVPixelFormat full_scale_yuvj_pix_fmts[] = {
84 FULL_SCALE_YUVJ_FORMATS, AV_PIX_FMT_NONE
87 static int query_formats(AVFilterContext *ctx)
89 static const enum AVPixelFormat pix_fmts[] = {
90 AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV411P,
91 AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P,
92 AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV444P,
93 AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P,
94 AV_PIX_FMT_GRAY8, FULL_SCALE_YUVJ_FORMATS,
98 ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
102 static av_cold void uninit(AVFilterContext *ctx)
104 TInterlaceContext *tinterlace = ctx->priv;
106 av_frame_free(&tinterlace->cur );
107 av_frame_free(&tinterlace->next);
108 av_freep(&tinterlace->black_data[0]);
111 static int config_out_props(AVFilterLink *outlink)
113 AVFilterContext *ctx = outlink->src;
114 AVFilterLink *inlink = outlink->src->inputs[0];
115 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(outlink->format);
116 TInterlaceContext *tinterlace = ctx->priv;
118 tinterlace->vsub = desc->log2_chroma_h;
119 outlink->flags |= FF_LINK_FLAG_REQUEST_LOOP;
120 outlink->w = inlink->w;
121 outlink->h = tinterlace->mode == MODE_MERGE || tinterlace->mode == MODE_PAD ?
122 inlink->h*2 : inlink->h;
124 if (tinterlace->mode == MODE_PAD) {
125 uint8_t black[4] = { 16, 128, 128, 16 };
127 if (ff_fmt_is_in(outlink->format, full_scale_yuvj_pix_fmts))
128 black[0] = black[3] = 0;
129 ret = av_image_alloc(tinterlace->black_data, tinterlace->black_linesize,
130 outlink->w, outlink->h, outlink->format, 1);
134 /* fill black picture with black */
135 for (i = 0; i < 4 && tinterlace->black_data[i]; i++) {
136 int h = i == 1 || i == 2 ? FF_CEIL_RSHIFT(outlink->h, desc->log2_chroma_h) : outlink->h;
137 memset(tinterlace->black_data[i], black[i],
138 tinterlace->black_linesize[i] * h);
141 if ((tinterlace->flags & TINTERLACE_FLAG_VLPF)
142 && !(tinterlace->mode == MODE_INTERLEAVE_TOP
143 || tinterlace->mode == MODE_INTERLEAVE_BOTTOM)) {
144 av_log(ctx, AV_LOG_WARNING, "low_pass_filter flag ignored with mode %d\n",
146 tinterlace->flags &= ~TINTERLACE_FLAG_VLPF;
148 if (tinterlace->mode == MODE_INTERLACEX2) {
149 outlink->time_base.num = inlink->time_base.num;
150 outlink->time_base.den = inlink->time_base.den * 2;
151 outlink->frame_rate = av_mul_q(inlink->frame_rate, (AVRational){2,1});
152 } else if (tinterlace->mode != MODE_PAD) {
153 outlink->frame_rate = av_mul_q(inlink->frame_rate, (AVRational){1,2});
156 av_log(ctx, AV_LOG_VERBOSE, "mode:%d filter:%s h:%d -> h:%d\n",
157 tinterlace->mode, (tinterlace->flags & TINTERLACE_FLAG_VLPF) ? "on" : "off",
158 inlink->h, outlink->h);
163 #define FIELD_UPPER 0
164 #define FIELD_LOWER 1
165 #define FIELD_UPPER_AND_LOWER 2
168 * Copy picture field from src to dst.
170 * @param src_field copy from upper, lower field or both
171 * @param interleave leave a padding line between each copied line
172 * @param dst_field copy to upper or lower field,
173 * only meaningful when interleave is selected
174 * @param flags context flags
177 void copy_picture_field(uint8_t *dst[4], int dst_linesize[4],
178 const uint8_t *src[4], int src_linesize[4],
179 enum AVPixelFormat format, int w, int src_h,
180 int src_field, int interleave, int dst_field,
183 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(format);
184 int plane, vsub = desc->log2_chroma_h;
185 int k = src_field == FIELD_UPPER_AND_LOWER ? 1 : 2;
188 for (plane = 0; plane < desc->nb_components; plane++) {
189 int lines = plane == 1 || plane == 2 ? FF_CEIL_RSHIFT(src_h, vsub) : src_h;
190 int linesize = av_image_get_linesize(format, w, plane);
191 uint8_t *dstp = dst[plane];
192 const uint8_t *srcp = src[plane];
197 lines = (lines + (src_field == FIELD_UPPER)) / k;
198 if (src_field == FIELD_LOWER)
199 srcp += src_linesize[plane];
200 if (interleave && dst_field == FIELD_LOWER)
201 dstp += dst_linesize[plane];
202 if (flags & TINTERLACE_FLAG_VLPF) {
203 // Low-pass filtering is required when creating an interlaced destination from
204 // a progressive source which contains high-frequency vertical detail.
205 // Filtering will reduce interlace 'twitter' and Moire patterning.
206 int srcp_linesize = src_linesize[plane] * k;
207 int dstp_linesize = dst_linesize[plane] * (interleave ? 2 : 1);
208 for (h = lines; h > 0; h--) {
209 const uint8_t *srcp_above = srcp - src_linesize[plane];
210 const uint8_t *srcp_below = srcp + src_linesize[plane];
211 if (h == lines) srcp_above = srcp; // there is no line above
212 if (h == 1) srcp_below = srcp; // there is no line below
213 for (i = 0; i < linesize; i++) {
214 // this calculation is an integer representation of
215 // '0.5 * current + 0.25 * above + 0.25 * below'
216 // '1 +' is for rounding. */
217 dstp[i] = (1 + srcp[i] + srcp[i] + srcp_above[i] + srcp_below[i]) >> 2;
219 dstp += dstp_linesize;
220 srcp += srcp_linesize;
223 av_image_copy_plane(dstp, dst_linesize[plane] * (interleave ? 2 : 1),
224 srcp, src_linesize[plane]*k, linesize, lines);
229 static int filter_frame(AVFilterLink *inlink, AVFrame *picref)
231 AVFilterContext *ctx = inlink->dst;
232 AVFilterLink *outlink = ctx->outputs[0];
233 TInterlaceContext *tinterlace = ctx->priv;
234 AVFrame *cur, *next, *out;
237 av_frame_free(&tinterlace->cur);
238 tinterlace->cur = tinterlace->next;
239 tinterlace->next = picref;
241 cur = tinterlace->cur;
242 next = tinterlace->next;
243 /* we need at least two frames */
244 if (!tinterlace->cur)
247 switch (tinterlace->mode) {
248 case MODE_MERGE: /* move the odd frame into the upper field of the new image, even into
249 * the lower field, generating a double-height video at half framerate */
250 out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
252 return AVERROR(ENOMEM);
253 av_frame_copy_props(out, cur);
254 out->height = outlink->h;
255 out->interlaced_frame = 1;
256 out->top_field_first = 1;
258 /* write odd frame lines into the upper field of the new frame */
259 copy_picture_field(out->data, out->linesize,
260 (const uint8_t **)cur->data, cur->linesize,
261 inlink->format, inlink->w, inlink->h,
262 FIELD_UPPER_AND_LOWER, 1, FIELD_UPPER, tinterlace->flags);
263 /* write even frame lines into the lower field of the new frame */
264 copy_picture_field(out->data, out->linesize,
265 (const uint8_t **)next->data, next->linesize,
266 inlink->format, inlink->w, inlink->h,
267 FIELD_UPPER_AND_LOWER, 1, FIELD_LOWER, tinterlace->flags);
268 av_frame_free(&tinterlace->next);
271 case MODE_DROP_ODD: /* only output even frames, odd frames are dropped; height unchanged, half framerate */
272 case MODE_DROP_EVEN: /* only output odd frames, even frames are dropped; height unchanged, half framerate */
273 out = av_frame_clone(tinterlace->mode == MODE_DROP_EVEN ? cur : next);
275 return AVERROR(ENOMEM);
276 av_frame_free(&tinterlace->next);
279 case MODE_PAD: /* expand each frame to double height, but pad alternate
280 * lines with black; framerate unchanged */
281 out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
283 return AVERROR(ENOMEM);
284 av_frame_copy_props(out, cur);
285 out->height = outlink->h;
287 field = (1 + tinterlace->frame) & 1 ? FIELD_UPPER : FIELD_LOWER;
288 /* copy upper and lower fields */
289 copy_picture_field(out->data, out->linesize,
290 (const uint8_t **)cur->data, cur->linesize,
291 inlink->format, inlink->w, inlink->h,
292 FIELD_UPPER_AND_LOWER, 1, field, tinterlace->flags);
293 /* pad with black the other field */
294 copy_picture_field(out->data, out->linesize,
295 (const uint8_t **)tinterlace->black_data, tinterlace->black_linesize,
296 inlink->format, inlink->w, inlink->h,
297 FIELD_UPPER_AND_LOWER, 1, !field, tinterlace->flags);
300 /* interleave upper/lower lines from odd frames with lower/upper lines from even frames,
301 * halving the frame rate and preserving image height */
302 case MODE_INTERLEAVE_TOP: /* top field first */
303 case MODE_INTERLEAVE_BOTTOM: /* bottom field first */
304 tff = tinterlace->mode == MODE_INTERLEAVE_TOP;
305 out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
307 return AVERROR(ENOMEM);
308 av_frame_copy_props(out, cur);
309 out->interlaced_frame = 1;
310 out->top_field_first = tff;
312 /* copy upper/lower field from cur */
313 copy_picture_field(out->data, out->linesize,
314 (const uint8_t **)cur->data, cur->linesize,
315 inlink->format, inlink->w, inlink->h,
316 tff ? FIELD_UPPER : FIELD_LOWER, 1, tff ? FIELD_UPPER : FIELD_LOWER,
318 /* copy lower/upper field from next */
319 copy_picture_field(out->data, out->linesize,
320 (const uint8_t **)next->data, next->linesize,
321 inlink->format, inlink->w, inlink->h,
322 tff ? FIELD_LOWER : FIELD_UPPER, 1, tff ? FIELD_LOWER : FIELD_UPPER,
324 av_frame_free(&tinterlace->next);
326 case MODE_INTERLACEX2: /* re-interlace preserving image height, double frame rate */
327 /* output current frame first */
328 out = av_frame_clone(cur);
330 return AVERROR(ENOMEM);
331 out->interlaced_frame = 1;
332 if (cur->pts != AV_NOPTS_VALUE)
333 out->pts = cur->pts*2;
335 if ((ret = ff_filter_frame(outlink, out)) < 0)
338 /* output mix of current and next frame */
339 tff = next->top_field_first;
340 out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
342 return AVERROR(ENOMEM);
343 av_frame_copy_props(out, next);
344 out->interlaced_frame = 1;
346 if (next->pts != AV_NOPTS_VALUE && cur->pts != AV_NOPTS_VALUE)
347 out->pts = cur->pts + next->pts;
349 out->pts = AV_NOPTS_VALUE;
350 /* write current frame second field lines into the second field of the new frame */
351 copy_picture_field(out->data, out->linesize,
352 (const uint8_t **)cur->data, cur->linesize,
353 inlink->format, inlink->w, inlink->h,
354 tff ? FIELD_LOWER : FIELD_UPPER, 1, tff ? FIELD_LOWER : FIELD_UPPER,
356 /* write next frame first field lines into the first field of the new frame */
357 copy_picture_field(out->data, out->linesize,
358 (const uint8_t **)next->data, next->linesize,
359 inlink->format, inlink->w, inlink->h,
360 tff ? FIELD_UPPER : FIELD_LOWER, 1, tff ? FIELD_UPPER : FIELD_LOWER,
367 ret = ff_filter_frame(outlink, out);
373 static const AVFilterPad tinterlace_inputs[] = {
376 .type = AVMEDIA_TYPE_VIDEO,
377 .filter_frame = filter_frame,
382 static const AVFilterPad tinterlace_outputs[] = {
385 .type = AVMEDIA_TYPE_VIDEO,
386 .config_props = config_out_props,
391 AVFilter ff_vf_tinterlace = {
392 .name = "tinterlace",
393 .description = NULL_IF_CONFIG_SMALL("Perform temporal field interlacing."),
394 .priv_size = sizeof(TInterlaceContext),
396 .query_formats = query_formats,
397 .inputs = tinterlace_inputs,
398 .outputs = tinterlace_outputs,
399 .priv_class = &tinterlace_class,