aboutsummaryrefslogtreecommitdiffstats
path: root/libavfilter/vf_decimate.c
blob: 53347c7f10936fd42754417e2b3fcb8c0d097826 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
/*
 * Copyright (c) 2012 Fredrik Mellbin
 * Copyright (c) 2013 Clément Bœsch
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"
#include "libavutil/timestamp.h"
#include "avfilter.h"
#include "internal.h"

#define INPUT_MAIN     0
#define INPUT_CLEANSRC 1

struct qitem {
    AVFrame *frame;
    int64_t maxbdiff;
    int64_t totdiff;
};

typedef struct DecimateContext {
    const AVClass *class;
    struct qitem *queue;    ///< window of cycle frames and the associated data diff
    int fid;                ///< current frame id in the queue
    int filled;             ///< 1 if the queue is filled, 0 otherwise
    AVFrame *last;          ///< last frame from the previous queue
    AVFrame **clean_src;    ///< frame queue for the clean source
    int got_frame[2];       ///< frame request flag for each input stream
    AVRational ts_unit;     ///< timestamp units for the output frames
    int64_t start_pts;      ///< base for output timestamps
    uint32_t eof;           ///< bitmask for end of stream
    int hsub, vsub;         ///< chroma subsampling values
    int depth;
    int nxblocks, nyblocks;
    int bdiffsize;
    int64_t *bdiffs;

    /* options */
    int cycle;
    double dupthresh_flt;
    double scthresh_flt;
    int64_t dupthresh;
    int64_t scthresh;
    int blockx, blocky;
    int ppsrc;
    int chroma;
} DecimateContext;

#define OFFSET(x) offsetof(DecimateContext, x)
#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM

static const AVOption decimate_options[] = {
    { "cycle",     "set the number of frame from which one will be dropped", OFFSET(cycle), AV_OPT_TYPE_INT, {.i64 = 5}, 2, 25, FLAGS },
    { "dupthresh", "set duplicate threshold",    OFFSET(dupthresh_flt), AV_OPT_TYPE_DOUBLE, {.dbl =  1.1}, 0, 100, FLAGS },
    { "scthresh",  "set scene change threshold", OFFSET(scthresh_flt),  AV_OPT_TYPE_DOUBLE, {.dbl = 15.0}, 0, 100, FLAGS },
    { "blockx",    "set the size of the x-axis blocks used during metric calculations", OFFSET(blockx), AV_OPT_TYPE_INT, {.i64 = 32}, 4, 1<<9, FLAGS },
    { "blocky",    "set the size of the y-axis blocks used during metric calculations", OFFSET(blocky), AV_OPT_TYPE_INT, {.i64 = 32}, 4, 1<<9, FLAGS },
    { "ppsrc",     "mark main input as a pre-processed input and activate clean source input stream", OFFSET(ppsrc), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS },
    { "chroma",    "set whether or not chroma is considered in the metric calculations", OFFSET(chroma), AV_OPT_TYPE_BOOL, {.i64=1}, 0, 1, FLAGS },
    { NULL }
};

AVFILTER_DEFINE_CLASS(decimate);

static void calc_diffs(const DecimateContext *dm, struct qitem *q,
                       const AVFrame *f1, const AVFrame *f2)
{
    int64_t maxdiff = -1;
    int64_t *bdiffs = dm->bdiffs;
    int plane, i, j;

    memset(bdiffs, 0, dm->bdiffsize * sizeof(*bdiffs));

    for (plane = 0; plane < (dm->chroma && f1->data[2] ? 3 : 1); plane++) {
        int x, y, xl;
        const int linesize1 = f1->linesize[plane];
        const int linesize2 = f2->linesize[plane];
        const uint8_t *f1p = f1->data[plane];
        const uint8_t *f2p = f2->data[plane];
        int width    = plane ? AV_CEIL_RSHIFT(f1->width,  dm->hsub) : f1->width;
        int height   = plane ? AV_CEIL_RSHIFT(f1->height, dm->vsub) : f1->height;
        int hblockx  = dm->blockx / 2;
        int hblocky  = dm->blocky / 2;

        if (plane) {
            hblockx >>= dm->hsub;
            hblocky >>= dm->vsub;
        }

        for (y = 0; y < height; y++) {
            int ydest = y / hblocky;
            int xdest = 0;

#define CALC_DIFF(nbits) do {                               \
    for (x = 0; x < width; x += hblockx) {                  \
        int64_t acc = 0;                                    \
        int m = FFMIN(width, x + hblockx);                  \
        for (xl = x; xl < m; xl++)                          \
            acc += abs(((const uint##nbits##_t *)f1p)[xl] - \
                       ((const uint##nbits##_t *)f2p)[xl]); \
        bdiffs[ydest * dm->nxblocks + xdest] += acc;        \
        xdest++;                                            \
    }                                                       \
} while (0)
            if (dm->depth == 8) CALC_DIFF(8);
            else                CALC_DIFF(16);

            f1p += linesize1;
            f2p += linesize2;
        }
    }

    for (i = 0; i < dm->nyblocks - 1; i++) {
        for (j = 0; j < dm->nxblocks - 1; j++) {
            int64_t tmp = bdiffs[      i * dm->nxblocks + j    ]
                        + bdiffs[      i * dm->nxblocks + j + 1]
                        + bdiffs[(i + 1) * dm->nxblocks + j    ]
                        + bdiffs[(i + 1) * dm->nxblocks + j + 1];
            if (tmp > maxdiff)
                maxdiff = tmp;
        }
    }

    q->totdiff = 0;
    for (i = 0; i < dm->bdiffsize; i++)
        q->totdiff += bdiffs[i];
    q->maxbdiff = maxdiff;
}

static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
    int scpos = -1, duppos = -1;
    int drop = INT_MIN, i, lowest = 0, ret;
    AVFilterContext *ctx  = inlink->dst;
    AVFilterLink *outlink = ctx->outputs[0];
    DecimateContext *dm   = ctx->priv;
    AVFrame *prv;

    /* update frames queue(s) */
    if (FF_INLINK_IDX(inlink) == INPUT_MAIN) {
        dm->queue[dm->fid].frame = in;
        dm->got_frame[INPUT_MAIN] = 1;
    } else {
        dm->clean_src[dm->fid] = in;
        dm->got_frame[INPUT_CLEANSRC] = 1;
    }
    if (!dm->got_frame[INPUT_MAIN] || (dm->ppsrc && !dm->got_frame[INPUT_CLEANSRC]))
        return 0;
    dm->got_frame[INPUT_MAIN] = dm->got_frame[INPUT_CLEANSRC] = 0;

    if (dm->ppsrc)
        in = dm->clean_src[dm->fid];

    if (in) {
        /* update frame metrics */
        prv = dm->fid ? (dm->ppsrc ? dm->clean_src[dm->fid - 1] : dm->queue[dm->fid - 1].frame) : dm->last;
        if (!prv) {
            dm->queue[dm->fid].maxbdiff = INT64_MAX;
            dm->queue[dm->fid].totdiff  = INT64_MAX;
        } else {
            calc_diffs(dm, &dm->queue[dm->fid], prv, in);
        }
        if (++dm->fid != dm->cycle)
            return 0;
        av_frame_free(&dm->last);
        dm->last = av_frame_clone(in);
        dm->fid = 0;

        /* we have a complete cycle, select the frame to drop */
        lowest = 0;
        for (i = 0; i < dm->cycle; i++) {
            if (dm->queue[i].totdiff > dm->scthresh)
                scpos = i;
            if (dm->queue[i].maxbdiff < dm->queue[lowest].maxbdiff)
                lowest = i;
        }
        if (dm->queue[lowest].maxbdiff < dm->dupthresh)
            duppos = lowest;
        drop = scpos >= 0 && duppos < 0 ? scpos : lowest;
    }

    /* metrics debug */
    if (av_log_get_level() >= AV_LOG_DEBUG) {
        av_log(ctx, AV_LOG_DEBUG, "1/%d frame drop:\n", dm->cycle);
        for (i = 0; i < dm->cycle && dm->queue[i].frame; i++) {
            av_log(ctx, AV_LOG_DEBUG,"  #%d: totdiff=%08"PRIx64" maxbdiff=%08"PRIx64"%s%s%s%s\n",
                   i + 1, dm->queue[i].totdiff, dm->queue[i].maxbdiff,
                   i == scpos  ? " sc"     : "",
                   i == duppos ? " dup"    : "",
                   i == lowest ? " lowest" : "",
                   i == drop   ? " [DROP]" : "");
        }
    }

    /* push all frames except the drop */
    ret = 0;
    for (i = 0; i < dm->cycle && dm->queue[i].frame; i++) {
        if (i == drop) {
            if (dm->ppsrc)
                av_frame_free(&dm->clean_src[i]);
            av_frame_free(&dm->queue[i].frame);
        } else {
            AVFrame *frame = dm->queue[i].frame;
            if (frame->pts != AV_NOPTS_VALUE && dm->start_pts == AV_NOPTS_VALUE)
                dm->start_pts = frame->pts;
            if (dm->ppsrc) {
                av_frame_free(&frame);
                frame = dm->clean_src[i];
            }
            frame->pts = av_rescale_q(outlink->frame_count_in, dm->ts_unit, (AVRational){1,1}) +
                         (dm->start_pts == AV_NOPTS_VALUE ? 0 : dm->start_pts);
            ret = ff_filter_frame(outlink, frame);
            if (ret < 0)
                break;
        }
    }

    return ret;
}

static int config_input(AVFilterLink *inlink)
{
    int max_value;
    AVFilterContext *ctx = inlink->dst;
    DecimateContext *dm = ctx->priv;
    const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
    const int w = inlink->w;
    const int h = inlink->h;

    dm->hsub      = pix_desc->log2_chroma_w;
    dm->vsub      = pix_desc->log2_chroma_h;
    dm->depth     = pix_desc->comp[0].depth;
    max_value     = (1 << dm->depth) - 1;
    dm->scthresh  = (int64_t)(((int64_t)max_value *          w * h          * dm->scthresh_flt)  / 100);
    dm->dupthresh = (int64_t)(((int64_t)max_value * dm->blockx * dm->blocky * dm->dupthresh_flt) / 100);
    dm->nxblocks  = (w + dm->blockx/2 - 1) / (dm->blockx/2);
    dm->nyblocks  = (h + dm->blocky/2 - 1) / (dm->blocky/2);
    dm->bdiffsize = dm->nxblocks * dm->nyblocks;
    dm->bdiffs    = av_malloc_array(dm->bdiffsize, sizeof(*dm->bdiffs));
    dm->queue     = av_calloc(dm->cycle, sizeof(*dm->queue));

    if (!dm->bdiffs || !dm->queue)
        return AVERROR(ENOMEM);

    if (dm->ppsrc) {
        dm->clean_src = av_calloc(dm->cycle, sizeof(*dm->clean_src));
        if (!dm->clean_src)
            return AVERROR(ENOMEM);
    }

    return 0;
}

static av_cold int decimate_init(AVFilterContext *ctx)
{
    DecimateContext *dm = ctx->priv;
    AVFilterPad pad = {
        .name         = av_strdup("main"),
        .type         = AVMEDIA_TYPE_VIDEO,
        .filter_frame = filter_frame,
        .config_props = config_input,
    };
    int ret;

    if (!pad.name)
        return AVERROR(ENOMEM);
    if ((ret = ff_insert_inpad(ctx, INPUT_MAIN, &pad)) < 0) {
        av_freep(&pad.name);
        return ret;
    }

    if (dm->ppsrc) {
        pad.name = av_strdup("clean_src");
        pad.config_props = NULL;
        if (!pad.name)
            return AVERROR(ENOMEM);
        if ((ret = ff_insert_inpad(ctx, INPUT_CLEANSRC, &pad)) < 0) {
            av_freep(&pad.name);
            return ret;
        }
    }

    if ((dm->blockx & (dm->blockx - 1)) ||
        (dm->blocky & (dm->blocky - 1))) {
        av_log(ctx, AV_LOG_ERROR, "blockx and blocky settings must be power of two\n");
        return AVERROR(EINVAL);
    }

    dm->start_pts = AV_NOPTS_VALUE;

    return 0;
}

static av_cold void decimate_uninit(AVFilterContext *ctx)
{
    int i;
    DecimateContext *dm = ctx->priv;

    av_frame_free(&dm->last);
    av_freep(&dm->bdiffs);
    av_freep(&dm->queue);
    av_freep(&dm->clean_src);
    for (i = 0; i < ctx->nb_inputs; i++)
        av_freep(&ctx->input_pads[i].name);
}

static int request_inlink(AVFilterContext *ctx, int lid)
{
    int ret = 0;
    DecimateContext *dm = ctx->priv;

    if (!dm->got_frame[lid]) {
        AVFilterLink *inlink = ctx->inputs[lid];
        ret = ff_request_frame(inlink);
        if (ret == AVERROR_EOF) { // flushing
            dm->eof |= 1 << lid;
            ret = filter_frame(inlink, NULL);
        }
    }
    return ret;
}

static int request_frame(AVFilterLink *outlink)
{
    int ret;
    AVFilterContext *ctx = outlink->src;
    DecimateContext *dm = ctx->priv;
    const uint32_t eof_mask = 1<<INPUT_MAIN | dm->ppsrc<<INPUT_CLEANSRC;

    if ((dm->eof & eof_mask) == eof_mask) // flush done?
        return AVERROR_EOF;
    if ((ret = request_inlink(ctx, INPUT_MAIN)) < 0)
        return ret;
    if (dm->ppsrc && (ret = request_inlink(ctx, INPUT_CLEANSRC)) < 0)
        return ret;
    return 0;
}

static int query_formats(AVFilterContext *ctx)
{
    static const enum AVPixelFormat pix_fmts[] = {
#define PF_NOALPHA(suf) AV_PIX_FMT_YUV420##suf,  AV_PIX_FMT_YUV422##suf,  AV_PIX_FMT_YUV444##suf
#define PF_ALPHA(suf)   AV_PIX_FMT_YUVA420##suf, AV_PIX_FMT_YUVA422##suf, AV_PIX_FMT_YUVA444##suf
#define PF(suf)         PF_NOALPHA(suf), PF_ALPHA(suf)
        PF(P), PF(P9), PF(P10), PF_NOALPHA(P12), PF_NOALPHA(P14), PF(P16),
        AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV411P, AV_PIX_FMT_YUV410P,
        AV_PIX_FMT_GRAY8, AV_PIX_FMT_GRAY16,
        AV_PIX_FMT_NONE
    };
    AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
    if (!fmts_list)
        return AVERROR(ENOMEM);
    return ff_set_common_formats(ctx, fmts_list);
}

static int config_output(AVFilterLink *outlink)
{
    AVFilterContext *ctx = outlink->src;
    DecimateContext *dm = ctx->priv;
    const AVFilterLink *inlink =
        ctx->inputs[dm->ppsrc ? INPUT_CLEANSRC : INPUT_MAIN];
    AVRational fps = inlink->frame_rate;

    if (!fps.num || !fps.den) {
        av_log(ctx, AV_LOG_ERROR, "The input needs a constant frame rate; "
               "current rate of %d/%d is invalid\n", fps.num, fps.den);
        return AVERROR(EINVAL);
    }
    fps = av_mul_q(fps, (AVRational){dm->cycle - 1, dm->cycle});
    av_log(ctx, AV_LOG_VERBOSE, "FPS: %d/%d -> %d/%d\n",
           inlink->frame_rate.num, inlink->frame_rate.den, fps.num, fps.den);
    outlink->time_base  = inlink->time_base;
    outlink->frame_rate = fps;
    outlink->sample_aspect_ratio = inlink->sample_aspect_ratio;
    outlink->w = inlink->w;
    outlink->h = inlink->h;
    dm->ts_unit = av_inv_q(av_mul_q(fps, outlink->time_base));
    return 0;
}

static const AVFilterPad decimate_outputs[] = {
    {
        .name          = "default",
        .type          = AVMEDIA_TYPE_VIDEO,
        .request_frame = request_frame,
        .config_props  = config_output,
    },
    { NULL }
};

AVFilter ff_vf_decimate = {
    .name          = "decimate",
    .description   = NULL_IF_CONFIG_SMALL("Decimate frames (post field matching filter)."),
    .init          = decimate_init,
    .uninit        = decimate_uninit,
    .priv_size     = sizeof(DecimateContext),
    .query_formats = query_formats,
    .outputs       = decimate_outputs,
    .priv_class    = &decimate_class,
    .flags         = AVFILTER_FLAG_DYNAMIC_INPUTS,
};