aboutsummaryrefslogtreecommitdiffstats
path: root/libavfilter/vf_eq.c
blob: f3855f66a3dc41d8a9ba2d6149332081447f03a5 (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
/*
 * Original MPlayer filters by Richard Felker, Hampa Hug, Daniel Moreno,
 * and Michael Niedermeyer.
 *
 * Copyright (c) 2014 James Darnley <james.darnley@gmail.com>
 * Copyright (c) 2015 Arwa Arif <arwaarif1994@gmail.com>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 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 General Public License for more details.
 *
 * You should have received a copy of the GNU 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.
 */

/**
 * @file
 * very simple video equalizer
 */

#include "libavutil/common.h"
#include "libavutil/imgutils.h"
#include "libavutil/opt.h"
#include "libavutil/pixdesc.h"

#include "filters.h"
#include "vf_eq.h"
#include "video.h"

static void create_lut(EQParameters *param)
{
    int i;
    double   g  = 1.0 / param->gamma;
    double   lw = 1.0 - param->gamma_weight;

    for (i = 0; i < 256; i++) {
        double v = i / 255.0;
        v = param->contrast * (v - 0.5) + 0.5 + param->brightness;

        if (v <= 0.0) {
            param->lut[i] = 0;
        } else {
            v = v * lw + pow(v, g) * param->gamma_weight;

            if (v >= 1.0)
                param->lut[i] = 255;
            else
                param->lut[i] = 256.0 * v;
        }
    }

    param->lut_clean = 1;
}

static void apply_lut(EQParameters *param, uint8_t *dst, int dst_stride,
                      const uint8_t *src, int src_stride, int w, int h)
{
    int x, y;

    if (!param->lut_clean)
        create_lut(param);

    for (y = 0; y < h; y++) {
        for (x = 0; x < w; x++) {
            dst[y * dst_stride + x] = param->lut[src[y * src_stride + x]];
        }
    }
}

static void check_values(EQParameters *param, EQContext *eq)
{
    if (param->contrast == 1.0 && param->brightness == 0.0 && param->gamma == 1.0)
        param->adjust = NULL;
    else if (param->gamma == 1.0 && fabs(param->contrast) < 7.9)
        param->adjust = eq->process;
    else
        param->adjust = apply_lut;
}

static void set_contrast(EQContext *eq)
{
    eq->contrast = av_clipf(av_expr_eval(eq->contrast_pexpr, eq->var_values, eq), -1000.0, 1000.0);
    eq->param[0].contrast = eq->contrast;
    eq->param[0].lut_clean = 0;
    check_values(&eq->param[0], eq);
}

static void set_brightness(EQContext *eq)
{
    eq->brightness = av_clipf(av_expr_eval(eq->brightness_pexpr, eq->var_values, eq), -1.0, 1.0);
    eq->param[0].brightness = eq->brightness;
    eq->param[0].lut_clean = 0;
    check_values(&eq->param[0], eq);
}

static void set_gamma(EQContext *eq)
{
    int i;

    eq->gamma        = av_clipf(av_expr_eval(eq->gamma_pexpr,        eq->var_values, eq), 0.1, 10.0);
    eq->gamma_r      = av_clipf(av_expr_eval(eq->gamma_r_pexpr,      eq->var_values, eq), 0.1, 10.0);
    eq->gamma_g      = av_clipf(av_expr_eval(eq->gamma_g_pexpr,      eq->var_values, eq), 0.1, 10.0);
    eq->gamma_b      = av_clipf(av_expr_eval(eq->gamma_b_pexpr,      eq->var_values, eq), 0.1, 10.0);
    eq->gamma_weight = av_clipf(av_expr_eval(eq->gamma_weight_pexpr, eq->var_values, eq), 0.0,  1.0);

    eq->param[0].gamma = eq->gamma * eq->gamma_g;
    eq->param[1].gamma = sqrt(eq->gamma_b / eq->gamma_g);
    eq->param[2].gamma = sqrt(eq->gamma_r / eq->gamma_g);

    for (i = 0; i < 3; i++) {
        eq->param[i].gamma_weight = eq->gamma_weight;
        eq->param[i].lut_clean = 0;
        check_values(&eq->param[i], eq);
    }
}

static void set_saturation(EQContext *eq)
{
    int i;

    eq->saturation = av_clipf(av_expr_eval(eq->saturation_pexpr, eq->var_values, eq), 0.0, 3.0);

    for (i = 1; i < 3; i++) {
        eq->param[i].contrast = eq->saturation;
        eq->param[i].lut_clean = 0;
        check_values(&eq->param[i], eq);
    }
}

static int set_expr(AVExpr **pexpr, const char *expr, const char *option, void *log_ctx)
{
    int ret;
    AVExpr *old = NULL;

    if (*pexpr)
        old = *pexpr;
    ret = av_expr_parse(pexpr, expr, var_names, NULL, NULL, NULL, NULL, 0, log_ctx);
    if (ret < 0) {
        av_log(log_ctx, AV_LOG_ERROR,
               "Error when parsing the expression '%s' for %s\n",
               expr, option);
        *pexpr = old;
        return ret;
    }

    av_expr_free(old);
    return 0;
}

static int initialize(AVFilterContext *ctx)
{
    EQContext *eq = ctx->priv;
    int ret;
    ff_eq_init(eq);

    if ((ret = set_expr(&eq->contrast_pexpr,     eq->contrast_expr,     "contrast",     ctx)) < 0 ||
        (ret = set_expr(&eq->brightness_pexpr,   eq->brightness_expr,   "brightness",   ctx)) < 0 ||
        (ret = set_expr(&eq->saturation_pexpr,   eq->saturation_expr,   "saturation",   ctx)) < 0 ||
        (ret = set_expr(&eq->gamma_pexpr,        eq->gamma_expr,        "gamma",        ctx)) < 0 ||
        (ret = set_expr(&eq->gamma_r_pexpr,      eq->gamma_r_expr,      "gamma_r",      ctx)) < 0 ||
        (ret = set_expr(&eq->gamma_g_pexpr,      eq->gamma_g_expr,      "gamma_g",      ctx)) < 0 ||
        (ret = set_expr(&eq->gamma_b_pexpr,      eq->gamma_b_expr,      "gamma_b",      ctx)) < 0 ||
        (ret = set_expr(&eq->gamma_weight_pexpr, eq->gamma_weight_expr, "gamma_weight", ctx)) < 0 )
        return ret;

    if (eq->eval_mode == EVAL_MODE_INIT) {
        set_gamma(eq);
        set_contrast(eq);
        set_brightness(eq);
        set_saturation(eq);
    }

    return 0;
}

static av_cold void uninit(AVFilterContext *ctx)
{
    EQContext *eq = ctx->priv;

    av_expr_free(eq->contrast_pexpr);     eq->contrast_pexpr     = NULL;
    av_expr_free(eq->brightness_pexpr);   eq->brightness_pexpr   = NULL;
    av_expr_free(eq->saturation_pexpr);   eq->saturation_pexpr   = NULL;
    av_expr_free(eq->gamma_pexpr);        eq->gamma_pexpr        = NULL;
    av_expr_free(eq->gamma_weight_pexpr); eq->gamma_weight_pexpr = NULL;
    av_expr_free(eq->gamma_r_pexpr);      eq->gamma_r_pexpr      = NULL;
    av_expr_free(eq->gamma_g_pexpr);      eq->gamma_g_pexpr      = NULL;
    av_expr_free(eq->gamma_b_pexpr);      eq->gamma_b_pexpr      = NULL;
}

static int config_props(AVFilterLink *inlink)
{
    FilterLink *l = ff_filter_link(inlink);
    EQContext *eq = inlink->dst->priv;

    eq->var_values[VAR_N] = 0;
    eq->var_values[VAR_R] = l->frame_rate.num == 0 || l->frame_rate.den == 0 ?
        NAN : av_q2d(l->frame_rate);

    return 0;
}

static const enum AVPixelFormat pixel_fmts_eq[] = {
    AV_PIX_FMT_GRAY8,
    AV_PIX_FMT_YUV410P,
    AV_PIX_FMT_YUV411P,
    AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUVA420P,
    AV_PIX_FMT_YUV422P, AV_PIX_FMT_YUVA422P,
    AV_PIX_FMT_YUV444P, AV_PIX_FMT_YUVA444P,
    AV_PIX_FMT_NONE
};

static int filter_frame(AVFilterLink *inlink, AVFrame *in)
{
    FilterLink *inl = ff_filter_link(inlink);
    AVFilterContext *ctx = inlink->dst;
    AVFilterLink *outlink = inlink->dst->outputs[0];
    EQContext *eq = ctx->priv;
    AVFrame *out;
    const AVPixFmtDescriptor *desc;
    int i;

    out = ff_get_video_buffer(outlink, inlink->w, inlink->h);
    if (!out) {
        av_frame_free(&in);
        return AVERROR(ENOMEM);
    }

    av_frame_copy_props(out, in);
    desc = av_pix_fmt_desc_get(inlink->format);

    eq->var_values[VAR_N]   = inl->frame_count_out;
#if FF_API_FRAME_PKT
FF_DISABLE_DEPRECATION_WARNINGS
    {
        int64_t pos = in->pkt_pos;
        eq->var_values[VAR_POS] = pos == -1 ? NAN : pos;
    }
FF_ENABLE_DEPRECATION_WARNINGS
#endif
    eq->var_values[VAR_T]   = TS2T(in->pts, inlink->time_base);

    if (eq->eval_mode == EVAL_MODE_FRAME) {
        set_gamma(eq);
        set_contrast(eq);
        set_brightness(eq);
        set_saturation(eq);
    }

    for (i = 0; i < desc->nb_components; i++) {
        int w = inlink->w;
        int h = inlink->h;

        if (i == 1 || i == 2) {
            w = AV_CEIL_RSHIFT(w, desc->log2_chroma_w);
            h = AV_CEIL_RSHIFT(h, desc->log2_chroma_h);
        }

        if (i == 3 || !eq->param[i].adjust)
            av_image_copy_plane(out->data[i], out->linesize[i],
                                in->data[i], in->linesize[i], w, h);

        else
            eq->param[i].adjust(&eq->param[i], out->data[i], out->linesize[i],
                                 in->data[i], in->linesize[i], w, h);
    }

    av_frame_free(&in);
    return ff_filter_frame(outlink, out);
}

static inline int set_param(AVExpr **pexpr, const char *args, const char *cmd,
                            void (*set_fn)(EQContext *eq), AVFilterContext *ctx)
{
    EQContext *eq = ctx->priv;
    int ret;
    if ((ret = set_expr(pexpr, args, cmd, ctx)) < 0)
        return ret;
    if (eq->eval_mode == EVAL_MODE_INIT)
        set_fn(eq);
    return 0;
}

static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
                           char *res, int res_len, int flags)
{
    EQContext *eq = ctx->priv;

#define SET_PARAM(param_name, set_fn_name)                              \
    if (!strcmp(cmd, #param_name)) return set_param(&eq->param_name##_pexpr, args, cmd, set_##set_fn_name, ctx);

         SET_PARAM(contrast, contrast)
    else SET_PARAM(brightness, brightness)
    else SET_PARAM(saturation, saturation)
    else SET_PARAM(gamma, gamma)
    else SET_PARAM(gamma_r, gamma)
    else SET_PARAM(gamma_g, gamma)
    else SET_PARAM(gamma_b, gamma)
    else SET_PARAM(gamma_weight, gamma)
    else return AVERROR(ENOSYS);
}

static const AVFilterPad eq_inputs[] = {
    {
        .name = "default",
        .type = AVMEDIA_TYPE_VIDEO,
        .filter_frame = filter_frame,
        .config_props = config_props,
    },
};

#define OFFSET(x) offsetof(EQContext, x)
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
#define TFLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
static const AVOption eq_options[] = {
    { "contrast",     "set the contrast adjustment, negative values give a negative image",
        OFFSET(contrast_expr),     AV_OPT_TYPE_STRING, {.str = "1.0"}, 0, 0, TFLAGS },
    { "brightness",   "set the brightness adjustment",
        OFFSET(brightness_expr),   AV_OPT_TYPE_STRING, {.str = "0.0"}, 0, 0, TFLAGS },
    { "saturation",   "set the saturation adjustment",
        OFFSET(saturation_expr),   AV_OPT_TYPE_STRING, {.str = "1.0"}, 0, 0, TFLAGS },
    { "gamma",        "set the initial gamma value",
        OFFSET(gamma_expr),        AV_OPT_TYPE_STRING, {.str = "1.0"}, 0, 0, TFLAGS },
    { "gamma_r",      "gamma value for red",
        OFFSET(gamma_r_expr),      AV_OPT_TYPE_STRING, {.str = "1.0"}, 0, 0, TFLAGS },
    { "gamma_g",      "gamma value for green",
        OFFSET(gamma_g_expr),      AV_OPT_TYPE_STRING, {.str = "1.0"}, 0, 0, TFLAGS },
    { "gamma_b",      "gamma value for blue",
        OFFSET(gamma_b_expr),      AV_OPT_TYPE_STRING, {.str = "1.0"}, 0, 0, TFLAGS },
    { "gamma_weight", "set the gamma weight which reduces the effect of gamma on bright areas",
        OFFSET(gamma_weight_expr), AV_OPT_TYPE_STRING, {.str = "1.0"}, 0, 0, TFLAGS },
    { "eval", "specify when to evaluate expressions", OFFSET(eval_mode), AV_OPT_TYPE_INT, {.i64 = EVAL_MODE_INIT}, 0, EVAL_MODE_NB-1, FLAGS, .unit = "eval" },
         { "init",  "eval expressions once during initialization", 0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_INIT},  .flags = FLAGS, .unit = "eval" },
         { "frame", "eval expressions per-frame",                  0, AV_OPT_TYPE_CONST, {.i64=EVAL_MODE_FRAME}, .flags = FLAGS, .unit = "eval" },
    { NULL }
};

AVFILTER_DEFINE_CLASS(eq);

const AVFilter ff_vf_eq = {
    .name            = "eq",
    .description     = NULL_IF_CONFIG_SMALL("Adjust brightness, contrast, gamma, and saturation."),
    .priv_size       = sizeof(EQContext),
    .priv_class      = &eq_class,
    FILTER_INPUTS(eq_inputs),
    FILTER_OUTPUTS(ff_video_default_filterpad),
    FILTER_PIXFMTS_ARRAY(pixel_fmts_eq),
    .process_command = process_command,
    .init            = initialize,
    .uninit          = uninit,
    .flags           = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC,
};