1 /*
2 * Copyright (c) 2020 Paul B Mahol
3 *
4 * This file is part of FFmpeg.
5 *
6 * FFmpeg is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * FFmpeg is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with FFmpeg; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19 */
20
21 #include "avfilter.h"
22 #include "formats.h"
23 #include "video.h"
24 #include "internal.h"
25 #include "libavutil/imgutils.h"
26 #include "libavutil/intreadwrite.h"
27 #include "libavutil/opt.h"
28 #include "libavutil/parseutils.h"
29 #include "libavutil/lfg.h"
30 #include "libavutil/random_seed.h"
31 #include <float.h>
32 #include <math.h>
33
34 typedef struct GradientsContext {
35 const AVClass *class;
36 int w, h;
37 int type;
38 AVRational frame_rate;
39 uint64_t pts;
40
41 uint8_t color_rgba[8][4];
42 int nb_colors;
43 int x0, y0, x1, y1;
44 float fx0, fy0, fx1, fy1;
45
46 int64_t seed;
47
48 AVLFG lfg;
49 int (*draw_slice)(AVFilterContext *ctx, void *arg, int job, int nb_jobs);
50 } GradientsContext;
51
52 #define OFFSET(x) offsetof(GradientsContext, x)
53 #define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
54
55 static const AVOption gradients_options[] = {
56 {"size", "set frame size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"}, 0, 0, FLAGS },
57 {"s", "set frame size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str="640x480"}, 0, 0, FLAGS },
58 {"rate", "set frame rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, INT_MAX, FLAGS },
59 {"r", "set frame rate", OFFSET(frame_rate), AV_OPT_TYPE_VIDEO_RATE, {.str="25"}, 0, INT_MAX, FLAGS },
60 {"c0", "set 1st color", OFFSET(color_rgba[0]), AV_OPT_TYPE_COLOR, {.str = "random"}, 0, 0, FLAGS },
61 {"c1", "set 2nd color", OFFSET(color_rgba[1]), AV_OPT_TYPE_COLOR, {.str = "random"}, 0, 0, FLAGS },
62 {"c2", "set 3rd color", OFFSET(color_rgba[2]), AV_OPT_TYPE_COLOR, {.str = "random"}, 0, 0, FLAGS },
63 {"c3", "set 4th color", OFFSET(color_rgba[3]), AV_OPT_TYPE_COLOR, {.str = "random"}, 0, 0, FLAGS },
64 {"c4", "set 5th color", OFFSET(color_rgba[4]), AV_OPT_TYPE_COLOR, {.str = "random"}, 0, 0, FLAGS },
65 {"c5", "set 6th color", OFFSET(color_rgba[5]), AV_OPT_TYPE_COLOR, {.str = "random"}, 0, 0, FLAGS },
66 {"c6", "set 7th color", OFFSET(color_rgba[6]), AV_OPT_TYPE_COLOR, {.str = "random"}, 0, 0, FLAGS },
67 {"c7", "set 8th color", OFFSET(color_rgba[7]), AV_OPT_TYPE_COLOR, {.str = "random"}, 0, 0, FLAGS },
68 {"x0", "set gradient line source x0", OFFSET(x0), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, FLAGS },
69 {"y0", "set gradient line source y0", OFFSET(y0), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, FLAGS },
70 {"x1", "set gradient line destination x1", OFFSET(x1), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, FLAGS },
71 {"y1", "set gradient line destination y1", OFFSET(y1), AV_OPT_TYPE_INT, {.i64=-1}, -1, INT_MAX, FLAGS },
72 {"nb_colors", "set the number of colors", OFFSET(nb_colors), AV_OPT_TYPE_INT, {.i64=2}, 2, 8, FLAGS },
73 {"n", "set the number of colors", OFFSET(nb_colors), AV_OPT_TYPE_INT, {.i64=2}, 2, 8, FLAGS },
74 {"seed", "set the seed", OFFSET(seed), AV_OPT_TYPE_INT64, {.i64=-1}, -1, UINT32_MAX, FLAGS },
75 {NULL},
76 };
77
78 AVFILTER_DEFINE_CLASS(gradients);
79
query_formats(AVFilterContext * ctx)80 static int query_formats(AVFilterContext *ctx)
81 {
82 static const enum AVPixelFormat pix_fmts[] = {
83 AV_PIX_FMT_RGBA,
84 AV_PIX_FMT_RGBA64,
85 AV_PIX_FMT_NONE
86 };
87
88 AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
89 if (!fmts_list)
90 return AVERROR(ENOMEM);
91 return ff_set_common_formats(ctx, fmts_list);
92 }
93
lerp_color(uint8_t c0[4],uint8_t c1[4],float x)94 static uint32_t lerp_color(uint8_t c0[4], uint8_t c1[4], float x)
95 {
96 const float y = 1.f - x;
97
98 return (lrint(c0[0] * y + c1[0] * x)) << 0 |
99 (lrint(c0[1] * y + c1[1] * x)) << 8 |
100 (lrint(c0[2] * y + c1[2] * x)) << 16 |
101 (lrint(c0[3] * y + c1[3] * x)) << 24;
102 }
103
lerp_color16(uint8_t c0[4],uint8_t c1[4],float x)104 static uint64_t lerp_color16(uint8_t c0[4], uint8_t c1[4], float x)
105 {
106 const float y = 1.f - x;
107
108 return (llrint((c0[0] * y + c1[0] * x) * 256)) << 0 |
109 (llrint((c0[1] * y + c1[1] * x) * 256)) << 16 |
110 (llrint((c0[2] * y + c1[2] * x) * 256)) << 32 |
111 (llrint((c0[3] * y + c1[3] * x) * 256)) << 48;
112 }
113
lerp_colors(uint8_t arr[3][4],int nb_colors,float step)114 static uint32_t lerp_colors(uint8_t arr[3][4], int nb_colors, float step)
115 {
116 float scl;
117 int i;
118
119 if (nb_colors == 1 || step <= 0.0) {
120 return arr[0][0] | (arr[0][1] << 8) | (arr[0][2] << 16) | (arr[0][3] << 24);
121 } else if (step >= 1.0) {
122 i = nb_colors - 1;
123 return arr[i][0] | (arr[i][1] << 8) | (arr[i][2] << 16) | (arr[i][3] << 24);
124 }
125
126 scl = step * (nb_colors - 1);
127 i = floorf(scl);
128
129 return lerp_color(arr[i], arr[i + 1], scl - i);
130 }
131
lerp_colors16(uint8_t arr[3][4],int nb_colors,float step)132 static uint64_t lerp_colors16(uint8_t arr[3][4], int nb_colors, float step)
133 {
134 float scl;
135 int i;
136
137 if (nb_colors == 1 || step <= 0.0) {
138 return ((uint64_t)arr[0][0] << 8) | ((uint64_t)arr[0][1] << 24) | ((uint64_t)arr[0][2] << 40) | ((uint64_t)arr[0][3] << 56);
139 } else if (step >= 1.0) {
140 i = nb_colors - 1;
141 return ((uint64_t)arr[i][0] << 8) | ((uint64_t)arr[i][1] << 24) | ((uint64_t)arr[i][2] << 40) | ((uint64_t)arr[i][3] << 56);
142 }
143
144 scl = step * (nb_colors - 1);
145 i = floorf(scl);
146
147 return lerp_color16(arr[i], arr[i + 1], scl - i);
148 }
149
project(float origin_x,float origin_y,float dest_x,float dest_y,int point_x,int point_y)150 static float project(float origin_x, float origin_y,
151 float dest_x, float dest_y,
152 int point_x, int point_y)
153 {
154 // Rise and run of line.
155 float od_x = dest_x - origin_x;
156 float od_y = dest_y - origin_y;
157
158 // Distance-squared of line.
159 float od_s_q = od_x * od_x + od_y * od_y;
160
161 // Rise and run of projection.
162 float op_x = point_x - origin_x;
163 float op_y = point_y - origin_y;
164 float op_x_od = op_x * od_x + op_y * od_y;
165
166 // Normalize and clamp range.
167 return av_clipf(op_x_od / od_s_q, 0.f, 1.f);
168 }
169
draw_gradients_slice(AVFilterContext * ctx,void * arg,int job,int nb_jobs)170 static int draw_gradients_slice(AVFilterContext *ctx, void *arg, int job, int nb_jobs)
171 {
172 GradientsContext *s = ctx->priv;
173 AVFrame *frame = arg;
174 const int width = frame->width;
175 const int height = frame->height;
176 const int start = (height * job ) / nb_jobs;
177 const int end = (height * (job+1)) / nb_jobs;
178 const int linesize = frame->linesize[0] / 4;
179 uint32_t *dst = (uint32_t *)frame->data[0] + start * linesize;
180
181 for (int y = start; y < end; y++) {
182 for (int x = 0; x < width; x++) {
183 float factor = project(s->fx0, s->fy0, s->fx1, s->fy1, x, y);
184 dst[x] = lerp_colors(s->color_rgba, s->nb_colors, factor);;
185 }
186
187 dst += linesize;
188 }
189
190 return 0;
191 }
192
draw_gradients_slice16(AVFilterContext * ctx,void * arg,int job,int nb_jobs)193 static int draw_gradients_slice16(AVFilterContext *ctx, void *arg, int job, int nb_jobs)
194 {
195 GradientsContext *s = ctx->priv;
196 AVFrame *frame = arg;
197 const int width = frame->width;
198 const int height = frame->height;
199 const int start = (height * job ) / nb_jobs;
200 const int end = (height * (job+1)) / nb_jobs;
201 const int linesize = frame->linesize[0] / 8;
202 uint64_t *dst = (uint64_t *)frame->data[0] + start * linesize;
203
204 for (int y = start; y < end; y++) {
205 for (int x = 0; x < width; x++) {
206 float factor = project(s->fx0, s->fy0, s->fx1, s->fy1, x, y);
207 dst[x] = lerp_colors16(s->color_rgba, s->nb_colors, factor);;
208 }
209
210 dst += linesize;
211 }
212
213 return 0;
214 }static int config_output(AVFilterLink *inlink)
215 {
216 AVFilterContext *ctx = inlink->src;
217 GradientsContext *s = ctx->priv;
218 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format);
219
220 if (av_image_check_size(s->w, s->h, 0, ctx) < 0)
221 return AVERROR(EINVAL);
222
223 inlink->w = s->w;
224 inlink->h = s->h;
225 inlink->time_base = av_inv_q(s->frame_rate);
226 inlink->sample_aspect_ratio = (AVRational) {1, 1};
227 if (s->seed == -1)
228 s->seed = av_get_random_seed();
229 av_lfg_init(&s->lfg, s->seed);
230
231 s->draw_slice = desc->comp[0].depth == 16 ? draw_gradients_slice16 : draw_gradients_slice;
232
233 if (s->x0 < 0 || s->x0 >= s->w)
234 s->x0 = av_lfg_get(&s->lfg) % s->w;
235 if (s->y0 < 0 || s->y0 >= s->h)
236 s->y0 = av_lfg_get(&s->lfg) % s->h;
237 if (s->x1 < 0 || s->x1 >= s->w)
238 s->x1 = av_lfg_get(&s->lfg) % s->w;
239 if (s->y1 < 0 || s->y1 >= s->h)
240 s->y1 = av_lfg_get(&s->lfg) % s->h;
241
242 return 0;
243 }
244
gradients_request_frame(AVFilterLink * outlink)245 static int gradients_request_frame(AVFilterLink *outlink)
246 {
247 AVFilterContext *ctx = outlink->src;
248 GradientsContext *s = ctx->priv;
249 AVFrame *frame = ff_get_video_buffer(outlink, s->w, s->h);
250 float angle = fmodf(s->pts / 100.f, 2.f * M_PI);
251 const float w2 = s->w / 2.f;
252 const float h2 = s->h / 2.f;
253
254 s->fx0 = (s->x0 - w2) * cosf(angle) - (s->y0 - h2) * sinf(angle) + w2;
255 s->fy0 = (s->x0 - w2) * sinf(angle) + (s->y0 - h2) * cosf(angle) + h2;
256
257 s->fx1 = (s->x1 - w2) * cosf(angle) - (s->y1 - h2) * sinf(angle) + w2;
258 s->fy1 = (s->x1 - w2) * sinf(angle) + (s->y1 - h2) * cosf(angle) + h2;
259
260 if (!frame)
261 return AVERROR(ENOMEM);
262
263 frame->sample_aspect_ratio = (AVRational) {1, 1};
264 frame->pts = s->pts++;
265
266 ctx->internal->execute(ctx, s->draw_slice, frame, NULL, FFMIN(outlink->h, ff_filter_get_nb_threads(ctx)));
267
268 return ff_filter_frame(outlink, frame);
269 }
270
271 static const AVFilterPad gradients_outputs[] = {
272 {
273 .name = "default",
274 .type = AVMEDIA_TYPE_VIDEO,
275 .request_frame = gradients_request_frame,
276 .config_props = config_output,
277 },
278 { NULL }
279 };
280
281 AVFilter ff_vsrc_gradients = {
282 .name = "gradients",
283 .description = NULL_IF_CONFIG_SMALL("Draw a gradients."),
284 .priv_size = sizeof(GradientsContext),
285 .priv_class = &gradients_class,
286 .query_formats = query_formats,
287 .inputs = NULL,
288 .outputs = gradients_outputs,
289 .flags = AVFILTER_FLAG_SLICE_THREADS,
290 };
291