libavfilter/vf_pad.c

   1 /*
   2  * Copyright (c) 2008 vmrsss
   3  * Copyright (c) 2009 Stefano Sabatini
   4  *
   5  * This file is part of Libav.
   6  *
   7  * Libav 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  * Libav 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 Libav; 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 padding filter
  25  */
  26
  27 #include "avfilter.h"
  28 #include "formats.h"
  29 #include "internal.h"
  30 #include "video.h"
  31 #include "libavutil/avstring.h"
  32 #include "libavutil/common.h"
  33 #include "libavutil/eval.h"
  34 #include "libavutil/pixdesc.h"
  35 #include "libavutil/colorspace.h"
  36 #include "libavutil/avassert.h"
  37 #include "libavutil/imgutils.h"
  38 #include "libavutil/parseutils.h"
  39 #include "libavutil/mathematics.h"
  40 #include "drawutils.h"
  41
  42 static const char *const var_names[] = {
  43     "PI",
  44     "PHI",
  45     "E",
  46     "in_w",   "iw",
  47     "in_h",   "ih",
  48     "out_w",  "ow",
  49     "out_h",  "oh",
  50     "x",
  51     "y",
  52     "a",
  53     "hsub",
  54     "vsub",
  55     NULL
  56 };
  57
  58 enum var_name {
  59     VAR_PI,
  60     VAR_PHI,
  61     VAR_E,
  62     VAR_IN_W,   VAR_IW,
  63     VAR_IN_H,   VAR_IH,
  64     VAR_OUT_W,  VAR_OW,
  65     VAR_OUT_H,  VAR_OH,
  66     VAR_X,
  67     VAR_Y,
  68     VAR_A,
  69     VAR_HSUB,
  70     VAR_VSUB,
  71     VARS_NB
  72 };
  73
  74 static int query_formats(AVFilterContext *ctx)
  75 {
  76     static const enum AVPixelFormat pix_fmts[] = {
  77         AV_PIX_FMT_ARGB,         AV_PIX_FMT_RGBA,
  78         AV_PIX_FMT_ABGR,         AV_PIX_FMT_BGRA,
  79         AV_PIX_FMT_RGB24,        AV_PIX_FMT_BGR24,
  80
  81         AV_PIX_FMT_YUV444P,      AV_PIX_FMT_YUV422P,
  82         AV_PIX_FMT_YUV420P,      AV_PIX_FMT_YUV411P,
  83         AV_PIX_FMT_YUV410P,      AV_PIX_FMT_YUV440P,
  84         AV_PIX_FMT_YUVJ444P,     AV_PIX_FMT_YUVJ422P,
  85         AV_PIX_FMT_YUVJ420P,     AV_PIX_FMT_YUVJ440P,
  86         AV_PIX_FMT_YUVA420P,
  87
  88         AV_PIX_FMT_NONE
  89     };
  90
  91     ff_set_common_formats(ctx, ff_make_format_list(pix_fmts));
  92     return 0;
  93 }
  94
  95 typedef struct {
  96     int w, h;               ///< output dimensions, a value of 0 will result in the input size
  97     int x, y;               ///< offsets of the input area with respect to the padded area
  98     int in_w, in_h;         ///< width and height for the padded input video, which has to be aligned to the chroma values in order to avoid chroma issues
  99
 100     char w_expr[256];       ///< width  expression string
 101     char h_expr[256];       ///< height expression string
 102     char x_expr[256];       ///< width  expression string
 103     char y_expr[256];       ///< height expression string
 104
 105     uint8_t color[4];       ///< color expressed either in YUVA or RGBA colorspace for the padding area
 106     uint8_t *line[4];
 107     int      line_step[4];
 108     int hsub, vsub;         ///< chroma subsampling values
 109 } PadContext;
 110
 111 static av_cold int init(AVFilterContext *ctx, const char *args)
 112 {
 113     PadContext *pad = ctx->priv;
 114     char color_string[128] = "black";
 115
 116     av_strlcpy(pad->w_expr, "iw", sizeof(pad->w_expr));
 117     av_strlcpy(pad->h_expr, "ih", sizeof(pad->h_expr));
 118     av_strlcpy(pad->x_expr, "0" , sizeof(pad->w_expr));
 119     av_strlcpy(pad->y_expr, "0" , sizeof(pad->h_expr));
 120
 121     if (args)
 122         sscanf(args, "%255[^:]:%255[^:]:%255[^:]:%255[^:]:%255s",
 123                pad->w_expr, pad->h_expr, pad->x_expr, pad->y_expr, color_string);
 124
 125     if (av_parse_color(pad->color, color_string, -1, ctx) < 0)
 126         return AVERROR(EINVAL);
 127
 128     return 0;
 129 }
 130
 131 static av_cold void uninit(AVFilterContext *ctx)
 132 {
 133     PadContext *pad = ctx->priv;
 134     int i;
 135
 136     for (i = 0; i < 4; i++) {
 137         av_freep(&pad->line[i]);
 138         pad->line_step[i] = 0;
 139     }
 140 }
 141
 142 static int config_input(AVFilterLink *inlink)
 143 {
 144     AVFilterContext *ctx = inlink->dst;
 145     PadContext *pad = ctx->priv;
 146     const AVPixFmtDescriptor *pix_desc = av_pix_fmt_desc_get(inlink->format);
 147     uint8_t rgba_color[4];
 148     int ret, is_packed_rgba;
 149     double var_values[VARS_NB], res;
 150     char *expr;
 151
 152     pad->hsub = pix_desc->log2_chroma_w;
 153     pad->vsub = pix_desc->log2_chroma_h;
 154
 155     var_values[VAR_PI]    = M_PI;
 156     var_values[VAR_PHI]   = M_PHI;
 157     var_values[VAR_E]     = M_E;
 158     var_values[VAR_IN_W]  = var_values[VAR_IW] = inlink->w;
 159     var_values[VAR_IN_H]  = var_values[VAR_IH] = inlink->h;
 160     var_values[VAR_OUT_W] = var_values[VAR_OW] = NAN;
 161     var_values[VAR_OUT_H] = var_values[VAR_OH] = NAN;
 162     var_values[VAR_A]     = (double) inlink->w / inlink->h;
 163     var_values[VAR_HSUB]  = 1<<pad->hsub;
 164     var_values[VAR_VSUB]  = 1<<pad->vsub;
 165
 166     /* evaluate width and height */
 167     av_expr_parse_and_eval(&res, (expr = pad->w_expr),
 168                            var_names, var_values,
 169                            NULL, NULL, NULL, NULL, NULL, 0, ctx);
 170     pad->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
 171     if ((ret = av_expr_parse_and_eval(&res, (expr = pad->h_expr),
 172                                       var_names, var_values,
 173                                       NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
 174         goto eval_fail;
 175     pad->h = var_values[VAR_OUT_H] = var_values[VAR_OH] = res;
 176     /* evaluate the width again, as it may depend on the evaluated output height */
 177     if ((ret = av_expr_parse_and_eval(&res, (expr = pad->w_expr),
 178                                       var_names, var_values,
 179                                       NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
 180         goto eval_fail;
 181     pad->w = var_values[VAR_OUT_W] = var_values[VAR_OW] = res;
 182
 183     /* evaluate x and y */
 184     av_expr_parse_and_eval(&res, (expr = pad->x_expr),
 185                            var_names, var_values,
 186                            NULL, NULL, NULL, NULL, NULL, 0, ctx);
 187     pad->x = var_values[VAR_X] = res;
 188     if ((ret = av_expr_parse_and_eval(&res, (expr = pad->y_expr),
 189                                       var_names, var_values,
 190                                       NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
 191         goto eval_fail;
 192     pad->y = var_values[VAR_Y] = res;
 193     /* evaluate x again, as it may depend on the evaluated y value */
 194     if ((ret = av_expr_parse_and_eval(&res, (expr = pad->x_expr),
 195                                       var_names, var_values,
 196                                       NULL, NULL, NULL, NULL, NULL, 0, ctx)) < 0)
 197         goto eval_fail;
 198     pad->x = var_values[VAR_X] = res;
 199
 200     /* sanity check params */
 201     if (pad->w < 0 || pad->h < 0 || pad->x < 0 || pad->y < 0) {
 202         av_log(ctx, AV_LOG_ERROR, "Negative values are not acceptable.\n");
 203         return AVERROR(EINVAL);
 204     }
 205
 206     if (!pad->w)
 207         pad->w = inlink->w;
 208     if (!pad->h)
 209         pad->h = inlink->h;
 210
 211     pad->w &= ~((1 << pad->hsub) - 1);
 212     pad->h &= ~((1 << pad->vsub) - 1);
 213     pad->x &= ~((1 << pad->hsub) - 1);
 214     pad->y &= ~((1 << pad->vsub) - 1);
 215
 216     pad->in_w = inlink->w & ~((1 << pad->hsub) - 1);
 217     pad->in_h = inlink->h & ~((1 << pad->vsub) - 1);
 218
 219     memcpy(rgba_color, pad->color, sizeof(rgba_color));
 220     ff_fill_line_with_color(pad->line, pad->line_step, pad->w, pad->color,
 221                             inlink->format, rgba_color, &is_packed_rgba, NULL);
 222
 223     av_log(ctx, AV_LOG_VERBOSE, "w:%d h:%d -> w:%d h:%d x:%d y:%d color:0x%02X%02X%02X%02X[%s]\n",
 224            inlink->w, inlink->h, pad->w, pad->h, pad->x, pad->y,
 225            pad->color[0], pad->color[1], pad->color[2], pad->color[3],
 226            is_packed_rgba ? "rgba" : "yuva");
 227
 228     if (pad->x <  0 || pad->y <  0                      ||
 229         pad->w <= 0 || pad->h <= 0                      ||
 230         (unsigned)pad->x + (unsigned)inlink->w > pad->w ||
 231         (unsigned)pad->y + (unsigned)inlink->h > pad->h) {
 232         av_log(ctx, AV_LOG_ERROR,
 233                "Input area %d:%d:%d:%d not within the padded area 0:0:%d:%d or zero-sized\n",
 234                pad->x, pad->y, pad->x + inlink->w, pad->y + inlink->h, pad->w, pad->h);
 235         return AVERROR(EINVAL);
 236     }
 237
 238     return 0;
 239
 240 eval_fail:
 241     av_log(NULL, AV_LOG_ERROR,
 242            "Error when evaluating the expression '%s'\n", expr);
 243     return ret;
 244
 245 }
 246
 247 static int config_output(AVFilterLink *outlink)
 248 {
 249     PadContext *pad = outlink->src->priv;
 250
 251     outlink->w = pad->w;
 252     outlink->h = pad->h;
 253     return 0;
 254 }
 255
 256 static AVFilterBufferRef *get_video_buffer(AVFilterLink *inlink, int perms, int w, int h)
 257 {
 258     PadContext *pad = inlink->dst->priv;
 259
 260     AVFilterBufferRef *picref = ff_get_video_buffer(inlink->dst->outputs[0], perms,
 261                                                     w + (pad->w - pad->in_w),
 262                                                     h + (pad->h - pad->in_h));
 263     int plane;
 264
 265     if (!picref)
 266         return NULL;
 267
 268     picref->video->w = w;
 269     picref->video->h = h;
 270
 271     for (plane = 0; plane < 4 && picref->data[plane]; plane++) {
 272         int hsub = (plane == 1 || plane == 2) ? pad->hsub : 0;
 273         int vsub = (plane == 1 || plane == 2) ? pad->vsub : 0;
 274
 275         picref->data[plane] += (pad->x >> hsub) * pad->line_step[plane] +
 276             (pad->y >> vsub) * picref->linesize[plane];
 277     }
 278
 279     return picref;
 280 }
 281
 282 static int does_clip(PadContext *pad, AVFilterBufferRef *outpicref, int plane, int hsub, int vsub, int x, int y)
 283 {
 284     int64_t x_in_buf, y_in_buf;
 285
 286     x_in_buf =  outpicref->data[plane] - outpicref->buf->data[plane]
 287              +  (x >> hsub) * pad      ->line_step[plane]
 288              +  (y >> vsub) * outpicref->linesize [plane];
 289
 290     if(x_in_buf < 0 || x_in_buf % pad->line_step[plane])
 291         return 1;
 292     x_in_buf /= pad->line_step[plane];
 293
 294     av_assert0(outpicref->buf->linesize[plane]>0); //while reference can use negative linesize the main buffer should not
 295
 296     y_in_buf = x_in_buf / outpicref->buf->linesize[plane];
 297     x_in_buf %= outpicref->buf->linesize[plane];
 298
 299     if(   y_in_buf<<vsub >= outpicref->buf->h
 300        || x_in_buf<<hsub >= outpicref->buf->w)
 301         return 1;
 302     return 0;
 303 }
 304
 305 static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *in)
 306 {
 307     PadContext *pad = inlink->dst->priv;
 308     AVFilterBufferRef *out = avfilter_ref_buffer(in, ~0);
 309     int plane, needs_copy;
 310
 311     if (!out) {
 312         avfilter_unref_bufferp(&in);
 313         return AVERROR(ENOMEM);
 314     }
 315
 316     for (plane = 0; plane < 4 && out->data[plane]; plane++) {
 317         int hsub = (plane == 1 || plane == 2) ? pad->hsub : 0;
 318         int vsub = (plane == 1 || plane == 2) ? pad->vsub : 0;
 319
 320         av_assert0(out->buf->w > 0 && out->buf->h > 0);
 321
 322         if (out->format != out->buf->format) //unsupported currently
 323             break;
 324
 325         out->data[plane] -= (pad->x  >> hsub) * pad->line_step[plane] +
 326                             (pad->y  >> vsub) * out->linesize [plane];
 327
 328         if (does_clip(pad, out, plane, hsub, vsub, 0,                   0) ||
 329             does_clip(pad, out, plane, hsub, vsub, 0,          pad->h - 1) ||
 330             does_clip(pad, out, plane, hsub, vsub, pad->w - 1,          0) ||
 331             does_clip(pad, out, plane, hsub, vsub, pad->w - 1, pad->h - 1))
 332             break;
 333     }
 334     needs_copy = plane < 4 && out->data[plane];
 335     if (needs_copy) {
 336         av_log(inlink->dst, AV_LOG_DEBUG, "Direct padding impossible allocating new frame\n");
 337         avfilter_unref_buffer(out);
 338         out = ff_get_video_buffer(inlink->dst->outputs[0], AV_PERM_WRITE | AV_PERM_NEG_LINESIZES,
 339                                   FFMAX(inlink->w, pad->w),
 340                                   FFMAX(inlink->h, pad->h));
 341         if (!out) {
 342             avfilter_unref_bufferp(&in);
 343             return AVERROR(ENOMEM);
 344         }
 345
 346         avfilter_copy_buffer_ref_props(out, in);
 347     }
 348
 349     out->video->w = pad->w;
 350     out->video->h = pad->h;
 351
 352     /* top bar */
 353     if (pad->y) {
 354         ff_draw_rectangle(out->data, out->linesize,
 355                           pad->line, pad->line_step, pad->hsub, pad->vsub,
 356                           0, 0, pad->w, pad->y);
 357     }
 358
 359     /* bottom bar */
 360     if (pad->h > pad->y + pad->in_h) {
 361         ff_draw_rectangle(out->data, out->linesize,
 362                           pad->line, pad->line_step, pad->hsub, pad->vsub,
 363                           0, pad->y + pad->in_h, pad->w, pad->h - pad->y - pad->in_h);
 364     }
 365
 366     /* left border */
 367     ff_draw_rectangle(out->data, out->linesize, pad->line, pad->line_step,
 368                       pad->hsub, pad->vsub, 0, pad->y, pad->x, in->video->h);
 369
 370     if (needs_copy) {
 371         ff_copy_rectangle(out->data, out->linesize, in->data, in->linesize,
 372                           pad->line_step, pad->hsub, pad->vsub,
 373                           pad->x, pad->y, 0, in->video->w, in->video->h);
 374     }
 375
 376     /* right border */
 377     ff_draw_rectangle(out->data, out->linesize,
 378                       pad->line, pad->line_step, pad->hsub, pad->vsub,
 379                       pad->x + pad->in_w, pad->y, pad->w - pad->x - pad->in_w,
 380                       in->video->h);
 381
 382     avfilter_unref_bufferp(&in);
 383     return ff_filter_frame(inlink->dst->outputs[0], out);
 384 }
 385
 386 static const AVFilterPad avfilter_vf_pad_inputs[] = {
 387     {
 388         .name             = "default",
 389         .type             = AVMEDIA_TYPE_VIDEO,
 390         .config_props     = config_input,
 391         .get_video_buffer = get_video_buffer,
 392         .filter_frame     = filter_frame,
 393     },
 394     { NULL }
 395 };
 396
 397 static const AVFilterPad avfilter_vf_pad_outputs[] = {
 398     {
 399         .name         = "default",
 400         .type         = AVMEDIA_TYPE_VIDEO,
 401         .config_props = config_output,
 402     },
 403     { NULL }
 404 };
 405
 406 AVFilter avfilter_vf_pad = {
 407     .name          = "pad",
 408     .description   = NULL_IF_CONFIG_SMALL("Pad input image to width:height[:x:y[:color]] (default x and y: 0, default color: black)."),
 409
 410     .priv_size     = sizeof(PadContext),
 411     .init          = init,
 412     .uninit        = uninit,
 413     .query_formats = query_formats,
 414
 415     .inputs    = avfilter_vf_pad_inputs,
 416
 417     .outputs   = avfilter_vf_pad_outputs,
 418 };