GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavfilter/vf_crop.c Lines: 117 166 70.5 %
Date: 2020-09-25 23:16:12 Branches: 38 82 46.3 %

Line Branch Exec Source
1
/*
2
 * Copyright (c) 2007 Bobby Bingham
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
/**
22
 * @file
23
 * video crop filter
24
 */
25
26
#include <stdio.h>
27
28
#include "avfilter.h"
29
#include "formats.h"
30
#include "internal.h"
31
#include "video.h"
32
#include "libavutil/eval.h"
33
#include "libavutil/avstring.h"
34
#include "libavutil/internal.h"
35
#include "libavutil/libm.h"
36
#include "libavutil/imgutils.h"
37
#include "libavutil/mathematics.h"
38
#include "libavutil/opt.h"
39
40
static const char *const var_names[] = {
41
    "in_w", "iw",   ///< width  of the input video
42
    "in_h", "ih",   ///< height of the input video
43
    "out_w", "ow",  ///< width  of the cropped video
44
    "out_h", "oh",  ///< height of the cropped video
45
    "a",
46
    "sar",
47
    "dar",
48
    "hsub",
49
    "vsub",
50
    "x",
51
    "y",
52
    "n",            ///< number of frame
53
    "pos",          ///< position in the file
54
    "t",            ///< timestamp expressed in seconds
55
    NULL
56
};
57
58
enum var_name {
59
    VAR_IN_W,  VAR_IW,
60
    VAR_IN_H,  VAR_IH,
61
    VAR_OUT_W, VAR_OW,
62
    VAR_OUT_H, VAR_OH,
63
    VAR_A,
64
    VAR_SAR,
65
    VAR_DAR,
66
    VAR_HSUB,
67
    VAR_VSUB,
68
    VAR_X,
69
    VAR_Y,
70
    VAR_N,
71
    VAR_POS,
72
    VAR_T,
73
    VAR_VARS_NB
74
};
75
76
typedef struct CropContext {
77
    const AVClass *class;
78
    int  x;             ///< x offset of the non-cropped area with respect to the input area
79
    int  y;             ///< y offset of the non-cropped area with respect to the input area
80
    int  w;             ///< width of the cropped area
81
    int  h;             ///< height of the cropped area
82
83
    AVRational out_sar; ///< output sample aspect ratio
84
    int keep_aspect;    ///< keep display aspect ratio when cropping
85
    int exact;          ///< exact cropping, for subsampled formats
86
87
    int max_step[4];    ///< max pixel step for each plane, expressed as a number of bytes
88
    int hsub, vsub;     ///< chroma subsampling
89
    char *x_expr, *y_expr, *w_expr, *h_expr;
90
    AVExpr *x_pexpr, *y_pexpr;  /* parsed expressions for x and y */
91
    double var_values[VAR_VARS_NB];
92
} CropContext;
93
94
164
static int query_formats(AVFilterContext *ctx)
95
{
96
164
    AVFilterFormats *formats = NULL;
97
    int ret;
98
99
164
    ret = ff_formats_pixdesc_filter(&formats, 0, AV_PIX_FMT_FLAG_BITSTREAM | FF_PIX_FMT_FLAG_SW_FLAT_SUB);
100
164
    if (ret < 0)
101
        return ret;
102
164
    return ff_set_common_formats(ctx, formats);
103
}
104
105
164
static av_cold void uninit(AVFilterContext *ctx)
106
{
107
164
    CropContext *s = ctx->priv;
108
109
164
    av_expr_free(s->x_pexpr);
110
164
    s->x_pexpr = NULL;
111
164
    av_expr_free(s->y_pexpr);
112
164
    s->y_pexpr = NULL;
113
164
}
114
115
716
static inline int normalize_double(int *n, double d)
116
{
117
716
    int ret = 0;
118
119
716
    if (isnan(d)) {
120
        ret = AVERROR(EINVAL);
121

716
    } else if (d > INT_MAX || d < INT_MIN) {
122
        *n = d > INT_MAX ? INT_MAX : INT_MIN;
123
        ret = AVERROR(EINVAL);
124
    } else
125
716
        *n = lrint(d);
126
127
716
    return ret;
128
}
129
130
163
static int config_input(AVFilterLink *link)
131
{
132
163
    AVFilterContext *ctx = link->dst;
133
163
    CropContext *s = ctx->priv;
134
163
    const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(link->format);
135
    int ret;
136
    const char *expr;
137
    double res;
138
139
163
    s->var_values[VAR_IN_W]  = s->var_values[VAR_IW] = ctx->inputs[0]->w;
140
163
    s->var_values[VAR_IN_H]  = s->var_values[VAR_IH] = ctx->inputs[0]->h;
141
163
    s->var_values[VAR_A]     = (float) link->w / link->h;
142
163
    s->var_values[VAR_SAR]   = link->sample_aspect_ratio.num ? av_q2d(link->sample_aspect_ratio) : 1;
143
163
    s->var_values[VAR_DAR]   = s->var_values[VAR_A] * s->var_values[VAR_SAR];
144
163
    s->var_values[VAR_HSUB]  = 1<<pix_desc->log2_chroma_w;
145
163
    s->var_values[VAR_VSUB]  = 1<<pix_desc->log2_chroma_h;
146
163
    s->var_values[VAR_X]     = NAN;
147
163
    s->var_values[VAR_Y]     = NAN;
148
163
    s->var_values[VAR_OUT_W] = s->var_values[VAR_OW] = NAN;
149
163
    s->var_values[VAR_OUT_H] = s->var_values[VAR_OH] = NAN;
150
163
    s->var_values[VAR_N]     = 0;
151
163
    s->var_values[VAR_T]     = NAN;
152
163
    s->var_values[VAR_POS]   = NAN;
153
154
163
    av_image_fill_max_pixsteps(s->max_step, NULL, pix_desc);
155
156
163
    if (pix_desc->flags & AV_PIX_FMT_FLAG_HWACCEL) {
157
        s->hsub = 1;
158
        s->vsub = 1;
159
    } else {
160
163
        s->hsub = pix_desc->log2_chroma_w;
161
163
        s->vsub = pix_desc->log2_chroma_h;
162
    }
163
164
163
    av_expr_parse_and_eval(&res, (expr = s->w_expr),
165
163
                           var_names, s->var_values,
166
                           NULL, NULL, NULL, NULL, NULL, 0, ctx);
167
163
    s->var_values[VAR_OUT_W] = s->var_values[VAR_OW] = res;
168
163
    if ((ret = av_expr_parse_and_eval(&res, (expr = s->h_expr),
169
163
                                      var_names, s->var_values,
170
                                      NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
171
        goto fail_expr;
172
163
    s->var_values[VAR_OUT_H] = s->var_values[VAR_OH] = res;
173
    /* evaluate again ow as it may depend on oh */
174
163
    if ((ret = av_expr_parse_and_eval(&res, (expr = s->w_expr),
175
163
                                      var_names, s->var_values,
176
                                      NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
177
        goto fail_expr;
178
179
163
    s->var_values[VAR_OUT_W] = s->var_values[VAR_OW] = res;
180

326
    if (normalize_double(&s->w, s->var_values[VAR_OUT_W]) < 0 ||
181
163
        normalize_double(&s->h, s->var_values[VAR_OUT_H]) < 0) {
182
        av_log(ctx, AV_LOG_ERROR,
183
               "Too big value or invalid expression for out_w/ow or out_h/oh. "
184
               "Maybe the expression for out_w:'%s' or for out_h:'%s' is self-referencing.\n",
185
               s->w_expr, s->h_expr);
186
        return AVERROR(EINVAL);
187
    }
188
189
163
    if (!s->exact) {
190
163
        s->w &= ~((1 << s->hsub) - 1);
191
163
        s->h &= ~((1 << s->vsub) - 1);
192
    }
193
194
163
    av_expr_free(s->x_pexpr);
195
163
    av_expr_free(s->y_pexpr);
196
163
    s->x_pexpr = s->y_pexpr = NULL;
197
163
    if ((ret = av_expr_parse(&s->x_pexpr, s->x_expr, var_names,
198
163
                             NULL, NULL, NULL, NULL, 0, ctx)) < 0 ||
199
163
        (ret = av_expr_parse(&s->y_pexpr, s->y_expr, var_names,
200
                             NULL, NULL, NULL, NULL, 0, ctx)) < 0)
201
        return AVERROR(EINVAL);
202
203
163
    if (s->keep_aspect) {
204
        AVRational dar = av_mul_q(link->sample_aspect_ratio,
205
                                  (AVRational){ link->w, link->h });
206
        av_reduce(&s->out_sar.num, &s->out_sar.den,
207
                  dar.num * s->h, dar.den * s->w, INT_MAX);
208
    } else
209
163
        s->out_sar = link->sample_aspect_ratio;
210
211
163
    av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d sar:%d/%d -> w:%d h:%d sar:%d/%d\n",
212
           link->w, link->h, link->sample_aspect_ratio.num, link->sample_aspect_ratio.den,
213
           s->w, s->h, s->out_sar.num, s->out_sar.den);
214
215

163
    if (s->w <= 0 || s->h <= 0 ||
216

163
        s->w > link->w || s->h > link->h) {
217
        av_log(ctx, AV_LOG_ERROR,
218
               "Invalid too big or non positive size for width '%d' or height '%d'\n",
219
               s->w, s->h);
220
        return AVERROR(EINVAL);
221
    }
222
223
    /* set default, required in the case the first computed value for x/y is NAN */
224
163
    s->x = (link->w - s->w) / 2;
225
163
    s->y = (link->h - s->h) / 2;
226
163
    if (!s->exact) {
227
163
        s->x &= ~((1 << s->hsub) - 1);
228
163
        s->y &= ~((1 << s->vsub) - 1);
229
    }
230
163
    return 0;
231
232
fail_expr:
233
    av_log(ctx, AV_LOG_ERROR, "Error when evaluating the expression '%s'\n", expr);
234
    return ret;
235
}
236
237
163
static int config_output(AVFilterLink *link)
238
{
239
163
    CropContext *s = link->src->priv;
240
163
    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
241
242
163
    if (desc->flags & AV_PIX_FMT_FLAG_HWACCEL) {
243
        // Hardware frames adjust the cropping regions rather than
244
        // changing the frame size.
245
    } else {
246
163
        link->w = s->w;
247
163
        link->h = s->h;
248
    }
249
163
    link->sample_aspect_ratio = s->out_sar;
250
251
163
    return 0;
252
}
253
254
195
static int filter_frame(AVFilterLink *link, AVFrame *frame)
255
{
256
195
    AVFilterContext *ctx = link->dst;
257
195
    CropContext *s = ctx->priv;
258
195
    const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(link->format);
259
    int i;
260
261
195
    s->var_values[VAR_N] = link->frame_count_out;
262
390
    s->var_values[VAR_T] = frame->pts == AV_NOPTS_VALUE ?
263
195
        NAN : frame->pts * av_q2d(link->time_base);
264
390
    s->var_values[VAR_POS] = frame->pkt_pos == -1 ?
265
195
        NAN : frame->pkt_pos;
266
195
    s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, NULL);
267
195
    s->var_values[VAR_Y] = av_expr_eval(s->y_pexpr, s->var_values, NULL);
268
    /* It is necessary if x is expressed from y  */
269
195
    s->var_values[VAR_X] = av_expr_eval(s->x_pexpr, s->var_values, NULL);
270
271
195
    normalize_double(&s->x, s->var_values[VAR_X]);
272
195
    normalize_double(&s->y, s->var_values[VAR_Y]);
273
274
195
    if (s->x < 0)
275
        s->x = 0;
276
195
    if (s->y < 0)
277
        s->y = 0;
278
195
    if ((unsigned)s->x + (unsigned)s->w > link->w)
279
        s->x = link->w - s->w;
280
195
    if ((unsigned)s->y + (unsigned)s->h > link->h)
281
        s->y = link->h - s->h;
282
195
    if (!s->exact) {
283
195
        s->x &= ~((1 << s->hsub) - 1);
284
195
        s->y &= ~((1 << s->vsub) - 1);
285
    }
286
287
195
    av_log(ctx, AV_LOG_TRACE, "n:%d t:%f pos:%f x:%d y:%d x+w:%d y+h:%d\n",
288
195
            (int)s->var_values[VAR_N], s->var_values[VAR_T], s->var_values[VAR_POS],
289
195
            s->x, s->y, s->x+s->w, s->y+s->h);
290
291
195
    if (desc->flags & AV_PIX_FMT_FLAG_HWACCEL) {
292
        frame->crop_top   += s->y;
293
        frame->crop_left  += s->x;
294
        frame->crop_bottom = frame->height - frame->crop_top - frame->crop_bottom - s->h;
295
        frame->crop_right  = frame->width  - frame->crop_left - frame->crop_right - s->w;
296
    } else {
297
195
        frame->width  = s->w;
298
195
        frame->height = s->h;
299
300
195
        frame->data[0] += s->y * frame->linesize[0];
301
195
        frame->data[0] += s->x * s->max_step[0];
302
303

195
        if (!(desc->flags & AV_PIX_FMT_FLAG_PAL || desc->flags & FF_PSEUDOPAL)) {
304
567
            for (i = 1; i < 3; i ++) {
305
378
                if (frame->data[i]) {
306
272
                    frame->data[i] += (s->y >> s->vsub) * frame->linesize[i];
307
272
                    frame->data[i] += (s->x * s->max_step[i]) >> s->hsub;
308
                }
309
            }
310
        }
311
312
        /* alpha plane */
313
195
        if (frame->data[3]) {
314
34
            frame->data[3] += s->y * frame->linesize[3];
315
34
            frame->data[3] += s->x * s->max_step[3];
316
        }
317
    }
318
319
195
    return ff_filter_frame(link->dst->outputs[0], frame);
320
}
321
322
static int process_command(AVFilterContext *ctx, const char *cmd, const char *args,
323
                           char *res, int res_len, int flags)
324
{
325
    CropContext *s = ctx->priv;
326
    int ret;
327
328
    if (   !strcmp(cmd, "out_w")  || !strcmp(cmd, "w")
329
        || !strcmp(cmd, "out_h")  || !strcmp(cmd, "h")
330
        || !strcmp(cmd, "x")      || !strcmp(cmd, "y")) {
331
332
        int old_x = s->x;
333
        int old_y = s->y;
334
        int old_w = s->w;
335
        int old_h = s->h;
336
337
        AVFilterLink *outlink = ctx->outputs[0];
338
        AVFilterLink *inlink  = ctx->inputs[0];
339
340
        av_opt_set(s, cmd, args, 0);
341
342
        if ((ret = config_input(inlink)) < 0) {
343
            s->x = old_x;
344
            s->y = old_y;
345
            s->w = old_w;
346
            s->h = old_h;
347
            return ret;
348
        }
349
350
        ret = config_output(outlink);
351
352
    } else
353
        ret = AVERROR(ENOSYS);
354
355
    return ret;
356
}
357
358
#define OFFSET(x) offsetof(CropContext, x)
359
#define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM
360
#define TFLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_RUNTIME_PARAM
361
362
static const AVOption crop_options[] = {
363
    { "out_w",       "set the width crop area expression",   OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, 0, 0, TFLAGS },
364
    { "w",           "set the width crop area expression",   OFFSET(w_expr), AV_OPT_TYPE_STRING, {.str = "iw"}, 0, 0, TFLAGS },
365
    { "out_h",       "set the height crop area expression",  OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, 0, 0, TFLAGS },
366
    { "h",           "set the height crop area expression",  OFFSET(h_expr), AV_OPT_TYPE_STRING, {.str = "ih"}, 0, 0, TFLAGS },
367
    { "x",           "set the x crop area expression",       OFFSET(x_expr), AV_OPT_TYPE_STRING, {.str = "(in_w-out_w)/2"}, 0, 0, TFLAGS },
368
    { "y",           "set the y crop area expression",       OFFSET(y_expr), AV_OPT_TYPE_STRING, {.str = "(in_h-out_h)/2"}, 0, 0, TFLAGS },
369
    { "keep_aspect", "keep aspect ratio",                    OFFSET(keep_aspect), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS },
370
    { "exact",       "do exact cropping",                    OFFSET(exact),  AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS },
371
    { NULL }
372
};
373
374
AVFILTER_DEFINE_CLASS(crop);
375
376
static const AVFilterPad avfilter_vf_crop_inputs[] = {
377
    {
378
        .name         = "default",
379
        .type         = AVMEDIA_TYPE_VIDEO,
380
        .filter_frame = filter_frame,
381
        .config_props = config_input,
382
    },
383
    { NULL }
384
};
385
386
static const AVFilterPad avfilter_vf_crop_outputs[] = {
387
    {
388
        .name         = "default",
389
        .type         = AVMEDIA_TYPE_VIDEO,
390
        .config_props = config_output,
391
    },
392
    { NULL }
393
};
394
395
AVFilter ff_vf_crop = {
396
    .name            = "crop",
397
    .description     = NULL_IF_CONFIG_SMALL("Crop the input video."),
398
    .priv_size       = sizeof(CropContext),
399
    .priv_class      = &crop_class,
400
    .query_formats   = query_formats,
401
    .uninit          = uninit,
402
    .inputs          = avfilter_vf_crop_inputs,
403
    .outputs         = avfilter_vf_crop_outputs,
404
    .process_command = process_command,
405
};