1/*
2 * Copyright (c) 2010 Brandon Mintern
3 * Copyright (c) 2007 Bobby Bingham
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22/**
23 * @file
24 * video fade filter
25 * based heavily on vf_negate.c by Bobby Bingham
26 */
27
28#include "libavutil/avassert.h"
29#include "libavutil/avstring.h"
30#include "libavutil/common.h"
31#include "libavutil/eval.h"
32#include "libavutil/opt.h"
33#include "libavutil/pixdesc.h"
34#include "avfilter.h"
35#include "drawutils.h"
36#include "formats.h"
37#include "internal.h"
38#include "video.h"
39
40#define R 0
41#define G 1
42#define B 2
43#define A 3
44
45#define Y 0
46#define U 1
47#define V 2
48
49#define FADE_IN  0
50#define FADE_OUT 1
51
52typedef struct FadeContext {
53    const AVClass *class;
54    int type;
55    int factor, fade_per_frame;
56    int start_frame, nb_frames;
57    int hsub, vsub, bpp;
58    unsigned int black_level, black_level_scaled;
59    uint8_t is_packed_rgb;
60    uint8_t rgba_map[4];
61    int alpha;
62    uint64_t start_time, duration;
63    enum {VF_FADE_WAITING=0, VF_FADE_FADING, VF_FADE_DONE} fade_state;
64    uint8_t color_rgba[4];  ///< fade color
65    int black_fade;         ///< if color_rgba is black
66} FadeContext;
67
68static av_cold int init(AVFilterContext *ctx)
69{
70    FadeContext *s = ctx->priv;
71
72    s->fade_per_frame = (1 << 16) / s->nb_frames;
73    s->fade_state = VF_FADE_WAITING;
74
75    if (s->duration != 0) {
76        // If duration (seconds) is non-zero, assume that we are not fading based on frames
77        s->nb_frames = 0; // Mostly to clean up logging
78    }
79
80    // Choose what to log. If both time-based and frame-based options, both lines will be in the log
81    if (s->start_frame || s->nb_frames) {
82        av_log(ctx, AV_LOG_VERBOSE,
83               "type:%s start_frame:%d nb_frames:%d alpha:%d\n",
84               s->type == FADE_IN ? "in" : "out", s->start_frame,
85               s->nb_frames,s->alpha);
86    }
87    if (s->start_time || s->duration) {
88        av_log(ctx, AV_LOG_VERBOSE,
89               "type:%s start_time:%f duration:%f alpha:%d\n",
90               s->type == FADE_IN ? "in" : "out", (s->start_time / (double)AV_TIME_BASE),
91               (s->duration / (double)AV_TIME_BASE),s->alpha);
92    }
93
94    s->black_fade = !memcmp(s->color_rgba, "\x00\x00\x00\xff", 4);
95    return 0;
96}
97
98static int query_formats(AVFilterContext *ctx)
99{
100    const FadeContext *s = ctx->priv;
101    static const enum AVPixelFormat pix_fmts[] = {
102        AV_PIX_FMT_YUV444P,  AV_PIX_FMT_YUV422P,  AV_PIX_FMT_YUV420P,
103        AV_PIX_FMT_YUV411P,  AV_PIX_FMT_YUV410P,
104        AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ420P,
105        AV_PIX_FMT_YUV440P,  AV_PIX_FMT_YUVJ440P,
106        AV_PIX_FMT_YUVA420P, AV_PIX_FMT_YUVA422P, AV_PIX_FMT_YUVA444P,
107        AV_PIX_FMT_RGB24,    AV_PIX_FMT_BGR24,
108        AV_PIX_FMT_ARGB,     AV_PIX_FMT_ABGR,
109        AV_PIX_FMT_RGBA,     AV_PIX_FMT_BGRA,
110        AV_PIX_FMT_NONE
111    };
112    static const enum AVPixelFormat pix_fmts_rgb[] = {
113        AV_PIX_FMT_RGB24,    AV_PIX_FMT_BGR24,
114        AV_PIX_FMT_ARGB,     AV_PIX_FMT_ABGR,
115        AV_PIX_FMT_RGBA,     AV_PIX_FMT_BGRA,
116        AV_PIX_FMT_NONE
117    };
118
119    if (s->black_fade)
120        ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
121    else
122        ff_set_common_formats(ctx, ff_make_format_list(pix_fmts_rgb));
123    return 0;
124}
125
126const static enum AVPixelFormat studio_level_pix_fmts[] = {
127    AV_PIX_FMT_YUV444P,  AV_PIX_FMT_YUV422P,  AV_PIX_FMT_YUV420P,
128    AV_PIX_FMT_YUV411P,  AV_PIX_FMT_YUV410P,
129    AV_PIX_FMT_YUV440P,
130    AV_PIX_FMT_NONE
131};
132
133static int config_props(AVFilterLink *inlink)
134{
135    FadeContext *s = inlink->dst->priv;
136    const AVPixFmtDescriptor *pixdesc = av_pix_fmt_desc_get(inlink->format);
137
138    s->hsub = pixdesc->log2_chroma_w;
139    s->vsub = pixdesc->log2_chroma_h;
140
141    s->bpp = av_get_bits_per_pixel(pixdesc) >> 3;
142    s->alpha &= !!(pixdesc->flags & AV_PIX_FMT_FLAG_ALPHA);
143    s->is_packed_rgb = ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0;
144
145    /* use CCIR601/709 black level for studio-level pixel non-alpha components */
146    s->black_level =
147            ff_fmt_is_in(inlink->format, studio_level_pix_fmts) && !s->alpha ? 16 : 0;
148    /* 32768 = 1 << 15, it is an integer representation
149     * of 0.5 and is for rounding. */
150    s->black_level_scaled = (s->black_level << 16) + 32768;
151    return 0;
152}
153
154static av_always_inline void filter_rgb(FadeContext *s, const AVFrame *frame,
155                                        int slice_start, int slice_end,
156                                        int do_alpha, int step)
157{
158    int i, j;
159    const uint8_t r_idx  = s->rgba_map[R];
160    const uint8_t g_idx  = s->rgba_map[G];
161    const uint8_t b_idx  = s->rgba_map[B];
162    const uint8_t a_idx  = s->rgba_map[A];
163    const uint8_t *c = s->color_rgba;
164
165    for (i = slice_start; i < slice_end; i++) {
166        uint8_t *p = frame->data[0] + i * frame->linesize[0];
167        for (j = 0; j < frame->width; j++) {
168#define INTERP(c_name, c_idx) av_clip_uint8(((c[c_idx]<<16) + ((int)p[c_name] - (int)c[c_idx]) * s->factor + (1<<15)) >> 16)
169            p[r_idx] = INTERP(r_idx, 0);
170            p[g_idx] = INTERP(g_idx, 1);
171            p[b_idx] = INTERP(b_idx, 2);
172            if (do_alpha)
173                p[a_idx] = INTERP(a_idx, 3);
174            p += step;
175        }
176    }
177}
178
179static int filter_slice_rgb(AVFilterContext *ctx, void *arg, int jobnr,
180                            int nb_jobs)
181{
182    FadeContext *s = ctx->priv;
183    AVFrame *frame = arg;
184    int slice_start = (frame->height *  jobnr   ) / nb_jobs;
185    int slice_end   = (frame->height * (jobnr+1)) / nb_jobs;
186
187    if      (s->alpha)    filter_rgb(s, frame, slice_start, slice_end, 1, 4);
188    else if (s->bpp == 3) filter_rgb(s, frame, slice_start, slice_end, 0, 3);
189    else if (s->bpp == 4) filter_rgb(s, frame, slice_start, slice_end, 0, 4);
190    else                  av_assert0(0);
191
192    return 0;
193}
194
195static int filter_slice_luma(AVFilterContext *ctx, void *arg, int jobnr,
196                             int nb_jobs)
197{
198    FadeContext *s = ctx->priv;
199    AVFrame *frame = arg;
200    int slice_start = (frame->height *  jobnr   ) / nb_jobs;
201    int slice_end   = (frame->height * (jobnr+1)) / nb_jobs;
202    int i, j;
203
204    for (i = slice_start; i < slice_end; i++) {
205        uint8_t *p = frame->data[0] + i * frame->linesize[0];
206        for (j = 0; j < frame->width * s->bpp; j++) {
207            /* s->factor is using 16 lower-order bits for decimal
208             * places. 32768 = 1 << 15, it is an integer representation
209             * of 0.5 and is for rounding. */
210            *p = ((*p - s->black_level) * s->factor + s->black_level_scaled) >> 16;
211            p++;
212        }
213    }
214
215    return 0;
216}
217
218static int filter_slice_chroma(AVFilterContext *ctx, void *arg, int jobnr,
219                               int nb_jobs)
220{
221    FadeContext *s = ctx->priv;
222    AVFrame *frame = arg;
223    int i, j, plane;
224    const int width = FF_CEIL_RSHIFT(frame->width, s->hsub);
225    const int height= FF_CEIL_RSHIFT(frame->height, s->vsub);
226    int slice_start = (height *  jobnr   ) / nb_jobs;
227    int slice_end   = (height * (jobnr+1)) / nb_jobs;
228
229    for (plane = 1; plane < 3; plane++) {
230        for (i = slice_start; i < slice_end; i++) {
231            uint8_t *p = frame->data[plane] + i * frame->linesize[plane];
232            for (j = 0; j < width; j++) {
233                /* 8421367 = ((128 << 1) + 1) << 15. It is an integer
234                 * representation of 128.5. The .5 is for rounding
235                 * purposes. */
236                *p = ((*p - 128) * s->factor + 8421367) >> 16;
237                p++;
238            }
239        }
240    }
241
242    return 0;
243}
244
245static int filter_slice_alpha(AVFilterContext *ctx, void *arg, int jobnr,
246                              int nb_jobs)
247{
248    FadeContext *s = ctx->priv;
249    AVFrame *frame = arg;
250    int plane = s->is_packed_rgb ? 0 : A;
251    int slice_start = (frame->height *  jobnr   ) / nb_jobs;
252    int slice_end   = (frame->height * (jobnr+1)) / nb_jobs;
253    int i, j;
254
255    for (i = slice_start; i < slice_end; i++) {
256        uint8_t *p = frame->data[plane] + i * frame->linesize[plane] + s->is_packed_rgb*s->rgba_map[A];
257        int step = s->is_packed_rgb ? 4 : 1;
258        for (j = 0; j < frame->width; j++) {
259            /* s->factor is using 16 lower-order bits for decimal
260             * places. 32768 = 1 << 15, it is an integer representation
261             * of 0.5 and is for rounding. */
262            *p = ((*p - s->black_level) * s->factor + s->black_level_scaled) >> 16;
263            p += step;
264        }
265    }
266
267    return 0;
268}
269
270static int filter_frame(AVFilterLink *inlink, AVFrame *frame)
271{
272    AVFilterContext *ctx = inlink->dst;
273    FadeContext *s       = ctx->priv;
274    double frame_timestamp = frame->pts == AV_NOPTS_VALUE ? -1 : frame->pts * av_q2d(inlink->time_base);
275
276    // Calculate Fade assuming this is a Fade In
277    if (s->fade_state == VF_FADE_WAITING) {
278        s->factor=0;
279        if (frame_timestamp >= s->start_time/(double)AV_TIME_BASE
280            && inlink->frame_count >= s->start_frame) {
281            // Time to start fading
282            s->fade_state = VF_FADE_FADING;
283
284            // Save start time in case we are starting based on frames and fading based on time
285            if (s->start_time == 0 && s->start_frame != 0) {
286                s->start_time = frame_timestamp*(double)AV_TIME_BASE;
287            }
288
289            // Save start frame in case we are starting based on time and fading based on frames
290            if (s->start_time != 0 && s->start_frame == 0) {
291                s->start_frame = inlink->frame_count;
292            }
293        }
294    }
295    if (s->fade_state == VF_FADE_FADING) {
296        if (s->duration == 0) {
297            // Fading based on frame count
298            s->factor = (inlink->frame_count - s->start_frame) * s->fade_per_frame;
299            if (inlink->frame_count > s->start_frame + s->nb_frames) {
300                s->fade_state = VF_FADE_DONE;
301            }
302
303        } else {
304            // Fading based on duration
305            s->factor = (frame_timestamp - s->start_time/(double)AV_TIME_BASE)
306                            * (float) UINT16_MAX / (s->duration/(double)AV_TIME_BASE);
307            if (frame_timestamp > s->start_time/(double)AV_TIME_BASE
308                                  + s->duration/(double)AV_TIME_BASE) {
309                s->fade_state = VF_FADE_DONE;
310            }
311        }
312    }
313    if (s->fade_state == VF_FADE_DONE) {
314        s->factor=UINT16_MAX;
315    }
316
317    s->factor = av_clip_uint16(s->factor);
318
319    // Invert fade_factor if Fading Out
320    if (s->type == FADE_OUT) {
321        s->factor=UINT16_MAX-s->factor;
322    }
323
324    if (s->factor < UINT16_MAX) {
325        if (s->alpha) {
326            ctx->internal->execute(ctx, filter_slice_alpha, frame, NULL,
327                                FFMIN(frame->height, ctx->graph->nb_threads));
328        } else if (s->is_packed_rgb && !s->black_fade) {
329            ctx->internal->execute(ctx, filter_slice_rgb, frame, NULL,
330                                   FFMIN(frame->height, ctx->graph->nb_threads));
331        } else {
332            /* luma, or rgb plane in case of black */
333            ctx->internal->execute(ctx, filter_slice_luma, frame, NULL,
334                                FFMIN(frame->height, ctx->graph->nb_threads));
335
336            if (frame->data[1] && frame->data[2]) {
337                /* chroma planes */
338                ctx->internal->execute(ctx, filter_slice_chroma, frame, NULL,
339                                    FFMIN(frame->height, ctx->graph->nb_threads));
340            }
341        }
342    }
343
344    return ff_filter_frame(inlink->dst->outputs[0], frame);
345}
346
347
348#define OFFSET(x) offsetof(FadeContext, x)
349#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
350
351static const AVOption fade_options[] = {
352    { "type", "'in' or 'out' for fade-in/fade-out", OFFSET(type), AV_OPT_TYPE_INT, { .i64 = FADE_IN }, FADE_IN, FADE_OUT, FLAGS, "type" },
353    { "t",    "'in' or 'out' for fade-in/fade-out", OFFSET(type), AV_OPT_TYPE_INT, { .i64 = FADE_IN }, FADE_IN, FADE_OUT, FLAGS, "type" },
354        { "in",  "fade-in",  0, AV_OPT_TYPE_CONST, { .i64 = FADE_IN },  .unit = "type" },
355        { "out", "fade-out", 0, AV_OPT_TYPE_CONST, { .i64 = FADE_OUT }, .unit = "type" },
356    { "start_frame", "Number of the first frame to which to apply the effect.",
357                                                    OFFSET(start_frame), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
358    { "s",           "Number of the first frame to which to apply the effect.",
359                                                    OFFSET(start_frame), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, INT_MAX, FLAGS },
360    { "nb_frames",   "Number of frames to which the effect should be applied.",
361                                                    OFFSET(nb_frames),   AV_OPT_TYPE_INT, { .i64 = 25 }, 0, INT_MAX, FLAGS },
362    { "n",           "Number of frames to which the effect should be applied.",
363                                                    OFFSET(nb_frames),   AV_OPT_TYPE_INT, { .i64 = 25 }, 0, INT_MAX, FLAGS },
364    { "alpha",       "fade alpha if it is available on the input", OFFSET(alpha),       AV_OPT_TYPE_INT, {.i64 = 0    }, 0,       1, FLAGS },
365    { "start_time",  "Number of seconds of the beginning of the effect.",
366                                                    OFFSET(start_time),  AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
367    { "st",          "Number of seconds of the beginning of the effect.",
368                                                    OFFSET(start_time),  AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
369    { "duration",    "Duration of the effect in seconds.",
370                                                    OFFSET(duration),    AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
371    { "d",           "Duration of the effect in seconds.",
372                                                    OFFSET(duration),    AV_OPT_TYPE_DURATION, {.i64 = 0. }, 0, INT32_MAX, FLAGS },
373    { "color",       "set color",                   OFFSET(color_rgba),  AV_OPT_TYPE_COLOR,    {.str = "black"}, CHAR_MIN, CHAR_MAX, FLAGS },
374    { "c",           "set color",                   OFFSET(color_rgba),  AV_OPT_TYPE_COLOR,    {.str = "black"}, CHAR_MIN, CHAR_MAX, FLAGS },
375    { NULL }
376};
377
378AVFILTER_DEFINE_CLASS(fade);
379
380static const AVFilterPad avfilter_vf_fade_inputs[] = {
381    {
382        .name           = "default",
383        .type           = AVMEDIA_TYPE_VIDEO,
384        .config_props   = config_props,
385        .filter_frame   = filter_frame,
386        .needs_writable = 1,
387    },
388    { NULL }
389};
390
391static const AVFilterPad avfilter_vf_fade_outputs[] = {
392    {
393        .name = "default",
394        .type = AVMEDIA_TYPE_VIDEO,
395    },
396    { NULL }
397};
398
399AVFilter ff_vf_fade = {
400    .name          = "fade",
401    .description   = NULL_IF_CONFIG_SMALL("Fade in/out input video."),
402    .init          = init,
403    .priv_size     = sizeof(FadeContext),
404    .priv_class    = &fade_class,
405    .query_formats = query_formats,
406    .inputs        = avfilter_vf_fade_inputs,
407    .outputs       = avfilter_vf_fade_outputs,
408    .flags         = AVFILTER_FLAG_SLICE_THREADS,
409};
410