gstalpha.c 32.6 KB
Newer Older
1 2
/* GStreamer
 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
3 4 5
 * Copyright (C) <2007> Wim Taymans <wim.taymans@collabora.co.uk>
 * Copyright (C) <2007> Edward Hervey <edward.hervey@collabora.co.uk>
 * Copyright (C) <2007> Jan Schmidt <thaytan@noraisin.net>
6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
26 27

#include "gstalpha.h"
28

29
#include <stdlib.h>
30
#include <string.h>
31
#include <math.h>
32

33 34 35 36
#ifndef M_PI
#define M_PI  3.14159265358979323846
#endif

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
/* Generated by -bad/ext/cog/generate_tables */
static const int cog_ycbcr_to_rgb_matrix_8bit_hdtv[] = {
  298, 0, 459, -63514,
  298, -55, -136, 19681,
  298, 541, 0, -73988,
};

static const int cog_ycbcr_to_rgb_matrix_8bit_sdtv[] = {
  298, 0, 409, -57068,
  298, -100, -208, 34707,
  298, 516, 0, -70870,
};

static const gint cog_rgb_to_ycbcr_matrix_8bit_hdtv[] = {
  47, 157, 16, 4096,
  -26, -87, 112, 32768,
  112, -102, -10, 32768,
};

static const gint cog_rgb_to_ycbcr_matrix_8bit_sdtv[] = {
  66, 129, 25, 4096,
  -38, -74, 112, 32768,
  112, -94, -18, 32768,
};

static const gint cog_ycbcr_sdtv_to_ycbcr_hdtv_matrix_8bit[] = {
  256, -30, -53, 10600,
  0, 261, 29, -4367,
  0, 19, 262, -3289,
};

static const gint cog_ycbcr_hdtv_to_ycbcr_sdtv_matrix_8bit[] = {
  256, 25, 49, -9536,
  0, 253, -28, 3958,
  0, -19, 252, 2918,
};

74 75 76 77 78 79 80
/* Alpha signals and args */
enum
{
  /* FILL ME */
  LAST_SIGNAL
};

81
#define DEFAULT_METHOD ALPHA_METHOD_SET
82 83 84 85 86 87
#define DEFAULT_ALPHA 1.0
#define DEFAULT_TARGET_R 0
#define DEFAULT_TARGET_G 255
#define DEFAULT_TARGET_B 0
#define DEFAULT_ANGLE 20.0
#define DEFAULT_NOISE_LEVEL 2.0
88 89
#define DEFAULT_BLACK_SENSITIVITY 100
#define DEFAULT_WHITE_SENSITIVITY 100
90

91 92
enum
{
93 94 95 96 97 98 99 100 101 102 103
  PROP_0,
  PROP_METHOD,
  PROP_ALPHA,
  PROP_TARGET_R,
  PROP_TARGET_G,
  PROP_TARGET_B,
  PROP_ANGLE,
  PROP_NOISE_LEVEL,
  PROP_BLACK_SENSITIVITY,
  PROP_WHITE_SENSITIVITY,
  PROP_LAST
104 105 106 107 108 109 110 111 112 113
};

static GstStaticPadTemplate gst_alpha_src_template =
GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("AYUV"))
    );

static GstStaticPadTemplate gst_alpha_sink_template =
114
    GST_STATIC_PAD_TEMPLATE ("sink",
115 116
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
117
    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("AYUV") ";" GST_VIDEO_CAPS_YUV ("I420")
118
    )
119 120
    );

121 122 123 124 125 126 127 128 129
static gboolean gst_alpha_start (GstBaseTransform * trans);
static gboolean gst_alpha_get_unit_size (GstBaseTransform * btrans,
    GstCaps * caps, guint * size);
static GstCaps *gst_alpha_transform_caps (GstBaseTransform * btrans,
    GstPadDirection direction, GstCaps * caps);
static gboolean gst_alpha_set_caps (GstBaseTransform * btrans,
    GstCaps * incaps, GstCaps * outcaps);
static GstFlowReturn gst_alpha_transform (GstBaseTransform * btrans,
    GstBuffer * in, GstBuffer * out);
130

131
static void gst_alpha_init_params (GstAlpha * alpha);
132
static gboolean gst_alpha_set_process_function (GstAlpha * alpha);
133 134 135 136 137 138

static void gst_alpha_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec);
static void gst_alpha_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec);

139
GST_BOILERPLATE (GstAlpha, gst_alpha, GstVideoFilter, GST_TYPE_VIDEO_FILTER);
140 141 142 143 144 145

#define GST_TYPE_ALPHA_METHOD (gst_alpha_method_get_type())
static GType
gst_alpha_method_get_type (void)
{
  static GType alpha_method_type = 0;
146
  static const GEnumValue alpha_method[] = {
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
147 148 149 150
    {ALPHA_METHOD_SET, "Set/adjust alpha channel", "set"},
    {ALPHA_METHOD_GREEN, "Chroma Key green", "green"},
    {ALPHA_METHOD_BLUE, "Chroma Key blue", "blue"},
    {ALPHA_METHOD_CUSTOM, "Chroma Key on target_r/g/b", "custom"},
151 152 153 154 155 156 157 158 159 160 161 162 163 164
    {0, NULL, NULL},
  };

  if (!alpha_method_type) {
    alpha_method_type = g_enum_register_static ("GstAlphaMethod", alpha_method);
  }
  return alpha_method_type;
}

static void
gst_alpha_base_init (gpointer g_class)
{
  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);

165 166 167 168 169 170
  gst_element_class_set_details_simple (element_class, "Alpha filter",
      "Filter/Effect/Video",
      "Adds an alpha channel to video - uniform or via chroma-keying",
      "Wim Taymans <wim@fluendo.com>\n"
      "Edward Hervey <edward.hervey@collabora.co.uk>\n"
      "Jan Schmidt <thaytan@noraisin.net>");
171 172 173 174 175

  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&gst_alpha_sink_template));
  gst_element_class_add_pad_template (element_class,
      gst_static_pad_template_get (&gst_alpha_src_template));
176 177 178

  GST_DEBUG_CATEGORY_INIT (gst_alpha_debug, "alpha", 0,
      "alpha - Element for adding alpha channel to streams");
179
}
180

181 182 183
static void
gst_alpha_class_init (GstAlphaClass * klass)
{
184 185
  GObjectClass *gobject_class = (GObjectClass *) klass;
  GstBaseTransformClass *btrans_class = (GstBaseTransformClass *) klass;
186

187 188 189
  gobject_class->set_property = gst_alpha_set_property;
  gobject_class->get_property = gst_alpha_get_property;

190
  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_METHOD,
191 192
      g_param_spec_enum ("method", "Method",
          "How the alpha channels should be created", GST_TYPE_ALPHA_METHOD,
193
          DEFAULT_METHOD, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
194
  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_ALPHA,
195
      g_param_spec_double ("alpha", "Alpha", "The value for the alpha channel",
196
          0.0, 1.0, DEFAULT_ALPHA,
197
          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
198
  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_TARGET_R,
199
      g_param_spec_uint ("target-r", "Target Red", "The Red target", 0, 255,
200
          DEFAULT_TARGET_R,
201
          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
202
  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_TARGET_G,
203
      g_param_spec_uint ("target-g", "Target Green", "The Green target", 0, 255,
204
          DEFAULT_TARGET_G,
205
          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
206
  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_TARGET_B,
207
      g_param_spec_uint ("target-b", "Target Blue", "The Blue target", 0, 255,
208
          DEFAULT_TARGET_B,
209
          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
210
  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_ANGLE,
211
      g_param_spec_float ("angle", "Angle", "Size of the colorcube to change",
212
          0.0, 90.0, DEFAULT_ANGLE,
213
          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
214
  g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_NOISE_LEVEL,
215
      g_param_spec_float ("noise-level", "Noise Level", "Size of noise radius",
216
          0.0, 64.0, DEFAULT_NOISE_LEVEL,
217
          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
218 219 220 221
  g_object_class_install_property (G_OBJECT_CLASS (klass),
      PROP_BLACK_SENSITIVITY, g_param_spec_uint ("black-sensitivity",
          "Black Sensitivity", "Sensitivity to dark colors", 0, 128,
          DEFAULT_BLACK_SENSITIVITY,
222
          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
223 224 225 226
  g_object_class_install_property (G_OBJECT_CLASS (klass),
      PROP_WHITE_SENSITIVITY, g_param_spec_uint ("white-sensitivity",
          "Sensitivity", "Sensitivity to bright colors", 0, 128,
          DEFAULT_WHITE_SENSITIVITY,
227
          G_PARAM_READWRITE | GST_PARAM_CONTROLLABLE | G_PARAM_STATIC_STRINGS));
228

229

230 231 232 233 234
  btrans_class->start = GST_DEBUG_FUNCPTR (gst_alpha_start);
  btrans_class->transform = GST_DEBUG_FUNCPTR (gst_alpha_transform);
  btrans_class->get_unit_size = GST_DEBUG_FUNCPTR (gst_alpha_get_unit_size);
  btrans_class->transform_caps = GST_DEBUG_FUNCPTR (gst_alpha_transform_caps);
  btrans_class->set_caps = GST_DEBUG_FUNCPTR (gst_alpha_set_caps);
235 236 237
}

static void
238
gst_alpha_init (GstAlpha * alpha, GstAlphaClass * klass)
239 240 241
{
  alpha->alpha = DEFAULT_ALPHA;
  alpha->method = DEFAULT_METHOD;
242 243 244 245 246
  alpha->target_r = DEFAULT_TARGET_R;
  alpha->target_g = DEFAULT_TARGET_G;
  alpha->target_b = DEFAULT_TARGET_B;
  alpha->angle = DEFAULT_ANGLE;
  alpha->noise_level = DEFAULT_NOISE_LEVEL;
247 248
  alpha->black_sensitivity = DEFAULT_BLACK_SENSITIVITY;
  alpha->white_sensitivity = DEFAULT_WHITE_SENSITIVITY;
249 250 251 252 253 254 255
}

/* do we need this function? */
static void
gst_alpha_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
256
  GstAlpha *alpha = GST_ALPHA (object);
257

258
  GST_OBJECT_LOCK (alpha);
259
  switch (prop_id) {
260
    case PROP_METHOD:
261
      alpha->method = g_value_get_enum (value);
262 263 264 265 266 267 268 269 270 271 272 273 274 275
      switch (alpha->method) {
        case ALPHA_METHOD_GREEN:
          alpha->target_r = 0;
          alpha->target_g = 255;
          alpha->target_b = 0;
          break;
        case ALPHA_METHOD_BLUE:
          alpha->target_r = 0;
          alpha->target_g = 0;
          alpha->target_b = 255;
          break;
        default:
          break;
      }
276
      gst_alpha_set_process_function (alpha);
277
      gst_alpha_init_params (alpha);
278
      break;
279
    case PROP_ALPHA:
280 281
      alpha->alpha = g_value_get_double (value);
      break;
282
    case PROP_TARGET_R:
283 284 285
      alpha->target_r = g_value_get_uint (value);
      gst_alpha_init_params (alpha);
      break;
286
    case PROP_TARGET_G:
287 288 289
      alpha->target_g = g_value_get_uint (value);
      gst_alpha_init_params (alpha);
      break;
290
    case PROP_TARGET_B:
291 292
      alpha->target_b = g_value_get_uint (value);
      gst_alpha_init_params (alpha);
293
      break;
294
    case PROP_ANGLE:
295 296 297
      alpha->angle = g_value_get_float (value);
      gst_alpha_init_params (alpha);
      break;
298
    case PROP_NOISE_LEVEL:
299 300
      alpha->noise_level = g_value_get_float (value);
      gst_alpha_init_params (alpha);
301
      break;
302 303 304 305 306 307
    case PROP_BLACK_SENSITIVITY:
      alpha->black_sensitivity = g_value_get_uint (value);
      break;
    case PROP_WHITE_SENSITIVITY:
      alpha->white_sensitivity = g_value_get_uint (value);
      break;
308 309 310 311
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
312
  GST_OBJECT_UNLOCK (alpha);
313
}
314

315 316 317 318
static void
gst_alpha_get_property (GObject * object, guint prop_id, GValue * value,
    GParamSpec * pspec)
{
319
  GstAlpha *alpha = GST_ALPHA (object);
320 321

  switch (prop_id) {
322
    case PROP_METHOD:
323 324
      g_value_set_enum (value, alpha->method);
      break;
325
    case PROP_ALPHA:
326 327
      g_value_set_double (value, alpha->alpha);
      break;
328
    case PROP_TARGET_R:
329 330
      g_value_set_uint (value, alpha->target_r);
      break;
331
    case PROP_TARGET_G:
332 333
      g_value_set_uint (value, alpha->target_g);
      break;
334
    case PROP_TARGET_B:
335
      g_value_set_uint (value, alpha->target_b);
336
      break;
337
    case PROP_ANGLE:
338 339
      g_value_set_float (value, alpha->angle);
      break;
340
    case PROP_NOISE_LEVEL:
341
      g_value_set_float (value, alpha->noise_level);
342
      break;
343 344 345 346 347 348
    case PROP_BLACK_SENSITIVITY:
      g_value_set_uint (value, alpha->black_sensitivity);
      break;
    case PROP_WHITE_SENSITIVITY:
      g_value_set_uint (value, alpha->white_sensitivity);
      break;
349 350 351 352 353 354
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

355
static gboolean
356 357
gst_alpha_get_unit_size (GstBaseTransform * btrans,
    GstCaps * caps, guint * size)
358
{
359 360 361 362 363 364 365 366
  GstVideoFormat format;
  gint width, height;

  if (!gst_video_format_parse_caps (caps, &format, &width, &height))
    return FALSE;

  *size = gst_video_format_get_size (format, width, height);

367
  GST_DEBUG_OBJECT (btrans, "unit size = %d for format %d w %d height %d",
368 369 370 371 372 373 374 375 376 377
      *size, format, width, height);

  return TRUE;
}

static GstCaps *
gst_alpha_transform_caps (GstBaseTransform * btrans,
    GstPadDirection direction, GstCaps * caps)
{
  GstCaps *ret;
378
  GstStructure *structure;
379 380
  gint i;

381
  ret = gst_caps_new_empty ();
382 383 384 385

  /* When going from the SINK pad to the src, we just need to make sure the
   * format is AYUV */
  if (direction == GST_PAD_SINK) {
386 387
    for (i = 0; i < gst_caps_get_size (caps); i++) {
      structure = gst_structure_copy (gst_caps_get_structure (caps, i));
388 389
      gst_structure_set (structure, "format",
          GST_TYPE_FOURCC, GST_MAKE_FOURCC ('A', 'Y', 'U', 'V'), NULL);
390 391 392
      gst_structure_remove_field (structure, "chroma-site");
      gst_structure_remove_field (structure, "color-matrix");
      gst_caps_append_structure (ret, structure);
393 394
    }
  } else {
395 396 397
    /* In the other direction, prepend a copy of the caps with format AYUV, 
     * and set the first to I420 */

398 399 400 401
    for (i = 0; i < gst_caps_get_size (caps); i++) {
      structure = gst_structure_copy (gst_caps_get_structure (caps, i));
      gst_structure_remove_field (structure, "color-matrix");

402 403
      gst_structure_set (structure, "format",
          GST_TYPE_FOURCC, GST_MAKE_FOURCC ('I', '4', '2', '0'), NULL);
404
      gst_caps_append_structure (ret, gst_structure_copy (structure));
405

406 407 408 409 410
      gst_structure_set (structure, "format",
          GST_TYPE_FOURCC, GST_MAKE_FOURCC ('A', 'Y', 'U', 'V'), NULL);
      gst_structure_remove_field (structure, "chroma-site");
      gst_caps_append_structure (ret, structure);
    }
411 412
  }

413 414 415 416 417 418 419 420 421 422
  gst_caps_do_simplify (ret);

  return ret;
}

static gboolean
gst_alpha_set_caps (GstBaseTransform * btrans,
    GstCaps * incaps, GstCaps * outcaps)
{
  GstAlpha *alpha = GST_ALPHA (btrans);
423 424 425
  const gchar *matrix;

  GST_OBJECT_LOCK (alpha);
426

427 428
  if (!gst_video_format_parse_caps (incaps, &alpha->in_format,
          &alpha->width, &alpha->height) ||
429
      !gst_video_format_parse_caps (outcaps, &alpha->out_format,
430 431
          &alpha->width, &alpha->height)) {
    GST_OBJECT_UNLOCK (alpha);
432
    return FALSE;
433 434 435 436 437 438 439 440 441 442 443 444 445 446 447
  }

  if (!gst_alpha_set_process_function (alpha)) {
    GST_OBJECT_UNLOCK (alpha);
    return FALSE;
  }

  matrix = gst_video_parse_caps_color_matrix (incaps);
  alpha->in_sdtv = matrix ? g_str_equal (matrix, "sdtv") : TRUE;

  matrix = gst_video_parse_caps_color_matrix (outcaps);
  alpha->out_sdtv = matrix ? g_str_equal (matrix, "sdtv") : TRUE;

  gst_alpha_init_params (alpha);
  GST_OBJECT_UNLOCK (alpha);
448

449
  return TRUE;
450 451
}

452 453 454 455 456 457
/* based on http://www.cs.utah.edu/~michael/chroma/
 */
static inline gint
chroma_keying_yuv (gint a, gint * y, guint ny, gint * u,
    gint * v, gint cr, gint cb, gint smin, gint smax, guint8 accept_angle_tg,
    guint8 accept_angle_ctg, guint8 one_over_kc, guint8 kfgy_scale, gint8 kg,
458
    guint noise_level2)
459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525
{
  gint tmp, tmp1;
  gint x1, y1;
  gint x, z;
  gint b_alpha;

  for (tmp = 0; tmp < ny; tmp++) {
    /* too dark or too bright, keep alpha */
    if (y[tmp] < smin || y[tmp] > smax)
      return a;
  }

  /* Convert foreground to XZ coords where X direction is defined by
     the key color */
  tmp = ((*u) * cb + (*v) * cr) >> 7;
  x = CLAMP (tmp, -128, 127);
  tmp = ((*v) * cb - (*u) * cr) >> 7;
  z = CLAMP (tmp, -128, 127);

  /* WARNING: accept angle should never be set greater than "somewhat less
     than 90 degrees" to avoid dealing with negative/infinite tg. In reality,
     80 degrees should be enough if foreground is reasonable. If this seems
     to be a problem, go to alternative ways of checking point position
     (scalar product or line equations). This angle should not be too small
     either to avoid infinite ctg (used to suppress foreground without use of
     division) */

  tmp = (x * accept_angle_tg) >> 4;
  tmp = MIN (tmp, 127);

  if (abs (z) > tmp) {
    /* keep foreground Kfg = 0 */
    return a;
  }
  /* Compute Kfg (implicitly) and Kbg, suppress foreground in XZ coord
     according to Kfg */
  tmp = (z * accept_angle_ctg) >> 4;
  tmp = CLAMP (tmp, -128, 127);
  x1 = abs (tmp);
  y1 = z;

  tmp1 = x - x1;
  tmp1 = MAX (tmp1, 0);
  b_alpha = (tmp1 * one_over_kc) / 2;
  b_alpha = 255 - CLAMP (b_alpha, 0, 255);
  b_alpha = (a * b_alpha) >> 8;

  tmp = (tmp1 * kfgy_scale) >> 4;
  tmp1 = MIN (tmp, 255);

  for (tmp = 0; tmp < ny; tmp++)
    y[tmp] = (y[tmp] < tmp1) ? 0 : y[tmp] - tmp1;

  /* Convert suppressed foreground back to CbCr */
  tmp = (x1 * cb - y1 * cr) >> 7;
  *u = CLAMP (tmp, -128, 127);

  tmp = (x1 * cr + y1 * cb) >> 7;
  *v = CLAMP (tmp, -128, 127);

  /* Deal with noise. For now, a circle around the key color with
     radius of noise_level treated as exact key color. Introduces
     sharp transitions.
   */
  tmp = z * z + (x - kg) * (x - kg);
  tmp = MIN (tmp, 0xffff);

526
  if (tmp < noise_level2)
527 528 529 530 531
    b_alpha = 0;

  return b_alpha;
}

532 533
#define APPLY_MATRIX(m,o,v1,v2,v3) ((m[o*4] * v1 + m[o*4+1] * v2 + m[o*4+2] * v3 + m[o*4+3]) >> 8)

534
static void
535 536 537 538 539 540
gst_alpha_set_ayuv_ayuv (const guint8 * src, guint8 * dest, gint width,
    gint height, GstAlpha * alpha)
{
  gint s_alpha = CLAMP ((gint) (alpha->alpha * 256), 0, 256);
  gint y, x;

541 542 543 544 545 546 547 548 549 550 551 552 553
  if (alpha->in_sdtv == alpha->out_sdtv) {
    for (y = 0; y < height; y++) {
      for (x = 0; x < width; x++) {
        dest[0] = (src[0] * s_alpha) >> 8;
        dest[1] = src[1];
        dest[2] = src[2];
        dest[3] = src[3];

        dest += 4;
        src += 4;
      }
    }
  } else {
554 555 556
    gint matrix[12];

    memcpy (matrix,
557
        alpha->out_sdtv ? cog_ycbcr_hdtv_to_ycbcr_sdtv_matrix_8bit :
558
        cog_ycbcr_sdtv_to_ycbcr_hdtv_matrix_8bit, 12 * sizeof (gint));
559 560 561 562 563 564 565 566 567 568 569

    for (y = 0; y < height; y++) {
      for (x = 0; x < width; x++) {
        dest[0] = (src[0] * s_alpha) >> 8;
        dest[1] = APPLY_MATRIX (matrix, 0, src[1], src[2], src[3]);
        dest[2] = APPLY_MATRIX (matrix, 1, src[1], src[2], src[3]);
        dest[3] = APPLY_MATRIX (matrix, 2, src[1], src[2], src[3]);

        dest += 4;
        src += 4;
      }
570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600
    }
  }
}

static void
gst_alpha_set_i420_ayuv (const guint8 * src, guint8 * dest, gint width,
    gint height, GstAlpha * alpha)
{
  gint b_alpha = CLAMP ((gint) (alpha->alpha * 255), 0, 255);
  const guint8 *srcY;
  const guint8 *srcU;
  const guint8 *srcV;
  gint i, j;
  gint src_wrap, src_uv_wrap;
  gint y_stride, uv_stride;
  gboolean odd_width;

  y_stride = gst_video_format_get_row_stride (GST_VIDEO_FORMAT_I420, 0, width);
  uv_stride = gst_video_format_get_row_stride (GST_VIDEO_FORMAT_I420, 1, width);

  src_wrap = y_stride - width;
  src_uv_wrap = uv_stride - (width / 2);

  srcY = src;
  srcU = src + gst_video_format_get_component_offset (GST_VIDEO_FORMAT_I420,
      1, width, height);
  srcV = src + gst_video_format_get_component_offset (GST_VIDEO_FORMAT_I420,
      2, width, height);

  odd_width = (width % 2 != 0);

601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635
  if (alpha->in_sdtv == alpha->out_sdtv) {
    for (i = 0; i < height; i++) {
      for (j = 0; j < width / 2; j++) {
        dest[0] = b_alpha;
        dest[1] = srcY[0];
        dest[2] = srcU[0];
        dest[3] = srcV[0];
        dest[4] = b_alpha;
        dest[5] = srcY[1];
        dest[6] = srcU[0];
        dest[7] = srcV[0];

        dest += 8;
        srcY += 2;
        srcU++;
        srcV++;
      }
      /* Might have one odd column left to do */
      if (odd_width) {
        dest[0] = b_alpha;
        dest[1] = srcY[0];
        dest[2] = srcU[0];
        dest[3] = srcV[0];

        dest += 4;
        srcY++;
      }
      if (i % 2 == 0) {
        srcU -= width / 2;
        srcV -= width / 2;
      } else {
        srcU += src_uv_wrap;
        srcV += src_uv_wrap;
      }
      srcY += src_wrap;
636
    }
637
  } else {
638 639 640
    gint matrix[12];

    memcpy (matrix,
641
        alpha->out_sdtv ? cog_ycbcr_hdtv_to_ycbcr_sdtv_matrix_8bit :
642
        cog_ycbcr_sdtv_to_ycbcr_hdtv_matrix_8bit, 12 * sizeof (gint));
643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677

    for (i = 0; i < height; i++) {
      for (j = 0; j < width / 2; j++) {
        dest[0] = b_alpha;
        dest[1] = APPLY_MATRIX (matrix, 0, srcY[0], srcU[0], srcV[0]);
        dest[2] = APPLY_MATRIX (matrix, 1, srcY[0], srcU[0], srcV[0]);
        dest[3] = APPLY_MATRIX (matrix, 2, srcY[0], srcU[0], srcV[0]);
        dest[4] = b_alpha;
        dest[5] = APPLY_MATRIX (matrix, 0, srcY[1], srcU[0], srcV[0]);
        dest[6] = APPLY_MATRIX (matrix, 1, srcY[1], srcU[0], srcV[0]);
        dest[7] = APPLY_MATRIX (matrix, 2, srcY[1], srcU[0], srcV[0]);

        dest += 8;
        srcY += 2;
        srcU++;
        srcV++;
      }
      /* Might have one odd column left to do */
      if (odd_width) {
        dest[0] = b_alpha;
        dest[1] = APPLY_MATRIX (matrix, 0, srcY[0], srcU[0], srcV[0]);
        dest[2] = APPLY_MATRIX (matrix, 1, srcY[0], srcU[0], srcV[0]);
        dest[3] = APPLY_MATRIX (matrix, 2, srcY[0], srcU[0], srcV[0]);

        dest += 4;
        srcY++;
      }
      if (i % 2 == 0) {
        srcU -= width / 2;
        srcV -= width / 2;
      } else {
        srcU += src_uv_wrap;
        srcV += src_uv_wrap;
      }
      srcY += src_wrap;
678 679 680 681 682 683
    }
  }
}

static void
gst_alpha_chroma_key_ayuv_ayuv (const guint8 * src, guint8 * dest, gint width,
684
    gint height, GstAlpha * alpha)
685
{
686
  const guint8 *src1;
687 688
  guint8 *dest1;
  gint i, j;
689
  gint a, y, u, v;
690
  gint smin, smax;
691
  gint pa = alpha->alpha * 255;
692 693 694 695 696 697 698
  gint8 cb = alpha->cb, cr = alpha->cr;
  gint8 kg = alpha->kg;
  guint8 accept_angle_tg = alpha->accept_angle_tg;
  guint8 accept_angle_ctg = alpha->accept_angle_ctg;
  guint8 one_over_kc = alpha->one_over_kc;
  guint8 kfgy_scale = alpha->kfgy_scale;
  guint noise_level2 = alpha->noise_level2;
699 700 701

  smin = 128 - alpha->black_sensitivity;
  smax = 128 + alpha->white_sensitivity;
702 703 704 705

  src1 = src;
  dest1 = dest;

706 707 708 709 710 711 712 713
  if (alpha->in_sdtv == alpha->out_sdtv) {
    for (i = 0; i < height; i++) {
      for (j = 0; j < width; j++) {
        a = (src1[0] * pa) >> 8;
        y = src1[1];
        u = src1[2] - 128;
        v = src1[3] - 128;

714 715 716
        a = chroma_keying_yuv (a, &y, 1, &u, &v, cr, cb,
            smin, smax, accept_angle_tg, accept_angle_ctg,
            one_over_kc, kfgy_scale, kg, noise_level2);
717 718 719 720 721 722 723 724 725 726 727 728 729 730

        u += 128;
        v += 128;

        dest1[0] = a;
        dest1[1] = y;
        dest1[2] = u;
        dest1[3] = v;

        src1 += 4;
        dest1 += 4;
      }
    }
  } else {
731 732 733
    gint matrix[12];

    memcpy (matrix,
734
        alpha->out_sdtv ? cog_ycbcr_hdtv_to_ycbcr_sdtv_matrix_8bit :
735
        cog_ycbcr_sdtv_to_ycbcr_hdtv_matrix_8bit, 12 * sizeof (gint));
736 737 738 739 740 741 742 743

    for (i = 0; i < height; i++) {
      for (j = 0; j < width; j++) {
        a = (src1[0] * pa) >> 8;
        y = APPLY_MATRIX (matrix, 0, src1[1], src1[2], src1[3]);
        u = APPLY_MATRIX (matrix, 1, src1[1], src1[2], src1[3]) - 128;
        v = APPLY_MATRIX (matrix, 2, src1[1], src1[2], src1[3]) - 128;

744 745 746
        a = chroma_keying_yuv (a, &y, 1, &u, &v, cr, cb,
            smin, smax, accept_angle_tg, accept_angle_ctg,
            one_over_kc, kfgy_scale, kg, noise_level2);
747 748 749 750 751 752 753 754 755 756 757 758

        u += 128;
        v += 128;

        dest1[0] = a;
        dest1[1] = y;
        dest1[2] = u;
        dest1[3] = v;

        src1 += 4;
        dest1 += 4;
      }
759 760 761 762
    }
  }
}

763
static inline void
764 765 766
gst_alpha_chromakey_row_i420_ayuv (GstAlpha * alpha, guint8 * dest1,
    guint8 * dest2, const guint8 * srcY1, const guint8 * srcY2,
    const guint8 * srcU, const guint8 * srcV, gint width)
767 768
{
  gint xpos;
769
  gint a, a2, u, v;
770
  gint smin, smax;
771 772 773 774 775 776 777
  gint8 cb = alpha->cb, cr = alpha->cr;
  gint8 kg = alpha->kg;
  guint8 accept_angle_tg = alpha->accept_angle_tg;
  guint8 accept_angle_ctg = alpha->accept_angle_ctg;
  guint8 one_over_kc = alpha->one_over_kc;
  guint8 kfgy_scale = alpha->kfgy_scale;
  guint noise_level2 = alpha->noise_level2;
778 779 780 781 782

  a = 255 * alpha->alpha;
  smin = 128 - alpha->black_sensitivity;
  smax = 128 + alpha->white_sensitivity;

783 784 785 786 787 788 789 790 791 792 793
  if (alpha->in_sdtv == alpha->out_sdtv) {
    gint y[4];

    for (xpos = 0; xpos < width / 2; xpos++) {
      y[0] = srcY1[0];
      y[1] = srcY1[1];
      y[2] = srcY2[0];
      y[3] = srcY2[1];
      u = srcU[0] - 128;
      v = srcV[0] - 128;

794 795 796
      a2 = chroma_keying_yuv (a, y, 4, &u, &v, cr, cb, smin,
          smax, accept_angle_tg, accept_angle_ctg,
          one_over_kc, kfgy_scale, kg, noise_level2);
797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826

      u += 128;
      v += 128;

      dest1[0] = a2;
      dest1[1] = y[0];
      dest1[2] = u;
      dest1[3] = v;
      dest1[4] = a2;
      dest1[5] = y[1];
      dest1[6] = u;
      dest1[7] = v;

      dest2[0] = a2;
      dest2[1] = y[2];
      dest2[2] = u;
      dest2[3] = v;
      dest2[4] = a2;
      dest2[5] = y[3];
      dest2[6] = u;
      dest2[7] = v;

      srcY1 += 2;
      srcY2 += 2;
      srcU++;
      srcV++;
      dest1 += 8;
      dest2 += 8;
    }
  } else {
827 828 829
    gint matrix[12], y;

    memcpy (matrix,
830
        alpha->out_sdtv ? cog_ycbcr_hdtv_to_ycbcr_sdtv_matrix_8bit :
831
        cog_ycbcr_sdtv_to_ycbcr_hdtv_matrix_8bit, 12 * sizeof (gint));
832 833 834 835 836 837

    for (xpos = 0; xpos < width / 2; xpos++) {
      y = APPLY_MATRIX (matrix, 0, srcY1[0], srcU[0], srcV[0]);
      u = APPLY_MATRIX (matrix, 1, srcY1[0], srcU[0], srcV[0]) - 128;
      v = APPLY_MATRIX (matrix, 2, srcY1[0], srcU[0], srcV[0]) - 128;

838 839 840
      a2 = chroma_keying_yuv (a, &y, 1, &u, &v, cr, cb, smin,
          smax, accept_angle_tg, accept_angle_ctg,
          one_over_kc, kfgy_scale, kg, noise_level2);
841 842 843 844 845 846 847 848 849 850 851 852 853

      u += 128;
      v += 128;

      dest1[0] = a2;
      dest1[1] = y;
      dest1[2] = u;
      dest1[3] = v;

      y = APPLY_MATRIX (matrix, 0, srcY1[1], srcU[0], srcV[0]);
      u = APPLY_MATRIX (matrix, 1, srcY1[1], srcU[0], srcV[0]) - 128;
      v = APPLY_MATRIX (matrix, 2, srcY1[1], srcU[0], srcV[0]) - 128;

854 855 856
      a2 = chroma_keying_yuv (a, &y, 1, &u, &v, cr, cb, smin,
          smax, accept_angle_tg, accept_angle_ctg,
          one_over_kc, kfgy_scale, kg, noise_level2);
857 858 859 860 861 862 863 864 865 866 867 868 869

      u += 128;
      v += 128;

      dest1[4] = a2;
      dest1[5] = y;
      dest1[6] = u;
      dest1[7] = v;

      y = APPLY_MATRIX (matrix, 0, srcY2[0], srcU[0], srcV[0]);
      u = APPLY_MATRIX (matrix, 1, srcY2[0], srcU[0], srcV[0]) - 128;
      v = APPLY_MATRIX (matrix, 2, srcY2[0], srcU[0], srcV[0]) - 128;

870 871 872
      a2 = chroma_keying_yuv (a, &y, 1, &u, &v, cr, cb, smin,
          smax, accept_angle_tg, accept_angle_ctg,
          one_over_kc, kfgy_scale, kg, noise_level2);
873 874 875 876 877 878 879 880 881 882 883 884 885

      u += 128;
      v += 128;

      dest2[0] = a2;
      dest2[1] = y;
      dest2[2] = u;
      dest2[3] = v;

      y = APPLY_MATRIX (matrix, 0, srcY2[1], srcU[0], srcV[0]);
      u = APPLY_MATRIX (matrix, 1, srcY2[1], srcU[0], srcV[0]) - 128;
      v = APPLY_MATRIX (matrix, 2, srcY2[1], srcU[0], srcV[0]) - 128;

886 887 888
      a2 = chroma_keying_yuv (a, &y, 1, &u, &v, cr, cb, smin,
          smax, accept_angle_tg, accept_angle_ctg,
          one_over_kc, kfgy_scale, kg, noise_level2);
889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904

      u += 128;
      v += 128;

      dest2[4] = a2;
      dest2[5] = y;
      dest2[6] = u;
      dest2[7] = v;

      srcY1 += 2;
      srcY2 += 2;
      srcU++;
      srcV++;
      dest1 += 8;
      dest2 += 8;
    }
905 906
  }
}
907

908
static void
909
gst_alpha_chroma_key_i420_ayuv (const guint8 * src, guint8 * dest, gint width,
910
    gint height, GstAlpha * alpha)
911
{
912
  const guint8 *srcY1, *srcY2, *srcU, *srcV;
913 914 915
  guint8 *dest1, *dest2;
  gint ypos;
  gint dest_stride, src_y_stride, src_uv_stride;
916

917 918 919 920 921 922
  dest_stride =
      gst_video_format_get_row_stride (GST_VIDEO_FORMAT_AYUV, 0, width);
  src_y_stride =
      gst_video_format_get_row_stride (GST_VIDEO_FORMAT_I420, 0, width);
  src_uv_stride =
      gst_video_format_get_row_stride (GST_VIDEO_FORMAT_I420, 1, width);
923

924 925
  srcY1 = src;
  srcY2 = src + src_y_stride;
926

927 928 929 930
  srcU = src + gst_video_format_get_component_offset (GST_VIDEO_FORMAT_I420,
      1, width, height);
  srcV = src + gst_video_format_get_component_offset (GST_VIDEO_FORMAT_I420,
      2, width, height);
931

932 933
  dest1 = dest;
  dest2 = dest + dest_stride;
934

935 936 937
  /* Redefine Y strides to skip 2 lines at a time ... */
  dest_stride *= 2;
  src_y_stride *= 2;
938

939
  for (ypos = 0; ypos < height / 2; ypos++) {
940
    gst_alpha_chromakey_row_i420_ayuv (alpha, dest1, dest2,
941
        srcY1, srcY2, srcU, srcV, width);
942

943 944 945 946 947 948
    dest1 += dest_stride;
    dest2 += dest_stride;
    srcY1 += src_y_stride;
    srcY2 += src_y_stride;
    srcU += src_uv_stride;
    srcV += src_uv_stride;
949 950 951
  }
}

952 953 954
static void
gst_alpha_init_params (GstAlpha * alpha)
{
955 956 957 958
  gfloat kgl;
  gfloat tmp;
  gfloat tmp1, tmp2;
  gfloat y;
959 960
  const gint *matrix;

961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982
  /* RGB->RGB: convert to SDTV YUV, chroma keying, convert back
   * YUV->RGB: chroma keying, convert to RGB
   * RGB->YUV: convert to YUV, chroma keying
   * YUV->YUV: convert matrix, chroma keying
   */
  if (gst_video_format_is_rgb (alpha->in_format)
      && gst_video_format_is_rgb (alpha->out_format))
    matrix = cog_rgb_to_ycbcr_matrix_8bit_sdtv;
  else if (gst_video_format_is_yuv (alpha->in_format)
      && gst_video_format_is_rgb (alpha->out_format))
    matrix =
        (alpha->in_sdtv) ? cog_rgb_to_ycbcr_matrix_8bit_sdtv :
        cog_rgb_to_ycbcr_matrix_8bit_hdtv;
  else if (gst_video_format_is_rgb (alpha->in_format)
      && gst_video_format_is_yuv (alpha->out_format))
    matrix =
        (alpha->out_sdtv) ? cog_rgb_to_ycbcr_matrix_8bit_sdtv :
        cog_rgb_to_ycbcr_matrix_8bit_hdtv;
  else                          /* yuv -> yuv */
    matrix =
        (alpha->out_sdtv) ? cog_rgb_to_ycbcr_matrix_8bit_sdtv :
        cog_rgb_to_ycbcr_matrix_8bit_hdtv;
983

984
  y = (matrix[0] * ((gint) alpha->target_r) +
985 986 987 988 989
      matrix[1] * ((gint) alpha->target_g) +
      matrix[2] * ((gint) alpha->target_b) + matrix[3]) >> 8;
  /* Cb,Cr without offset here because the chroma keying
   * works with them being in range [-128,127]
   */
990
  tmp1 =
991 992 993
      (matrix[4] * ((gint) alpha->target_r) +
      matrix[5] * ((gint) alpha->target_g) +
      matrix[6] * ((gint) alpha->target_b)) >> 8;
994
  tmp2 =
995 996 997 998
      (matrix[8] * ((gint) alpha->target_r) +
      matrix[9] * ((gint) alpha->target_g) +
      matrix[10] * ((gint) alpha->target_b)) >> 8;

999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010
  kgl = sqrt (tmp1 * tmp1 + tmp2 * tmp2);
  alpha->cb = 127 * (tmp1 / kgl);
  alpha->cr = 127 * (tmp2 / kgl);

  tmp = 15 * tan (M_PI * alpha->angle / 180);
  tmp = MIN (tmp, 255);
  alpha->accept_angle_tg = tmp;
  tmp = 15 / tan (M_PI * alpha->angle / 180);
  tmp = MIN (tmp, 255);
  alpha->accept_angle_ctg = tmp;
  tmp = 1 / (kgl);
  alpha->one_over_kc = 255 * 2 * tmp - 255;
1011
  tmp = 15 * y / kgl;
1012 1013 1014
  tmp = MIN (tmp, 255);
  alpha->kfgy_scale = tmp;
  alpha->kg = MIN (kgl, 127);
1015 1016

  alpha->noise_level2 = alpha->noise_level * alpha->noise_level;
1017 1018
}

1019 1020 1021 1022 1023 1024 1025 1026 1027 1028
static gboolean
gst_alpha_set_process_function (GstAlpha * alpha)
{
  alpha->process = NULL;
  switch (alpha->method) {
    case ALPHA_METHOD_SET:
      switch (alpha->out_format) {
        case GST_VIDEO_FORMAT_AYUV:
          switch (alpha->in_format) {
            case GST_VIDEO_FORMAT_AYUV:
1029
              alpha->process = gst_alpha_set_ayuv_ayuv;
1030 1031
              break;
            case GST_VIDEO_FORMAT_I420:
1032
              alpha->process = gst_alpha_set_i420_ayuv;
1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047
              break;
            default:
              break;
          }
        default:
          break;
      }
      break;
    case ALPHA_METHOD_GREEN:
    case ALPHA_METHOD_BLUE:
    case ALPHA_METHOD_CUSTOM:
      switch (alpha->out_format) {
        case GST_VIDEO_FORMAT_AYUV:
          switch (alpha->in_format) {
            case GST_VIDEO_FORMAT_AYUV:
1048
              alpha->process = gst_alpha_chroma_key_ayuv_ayuv;
1049 1050
              break;
            case GST_VIDEO_FORMAT_I420:
1051
              alpha->process = gst_alpha_chroma_key_i420_ayuv;
1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065
              break;
            default:
              break;
          }
        default:
          break;
      }
      break;
    default:
      break;
  }
  return alpha->process != NULL;
}

1066
static gboolean
1067
gst_alpha_start (GstBaseTransform * btrans)
1068
{
1069
  GstAlpha *alpha = GST_ALPHA (btrans);
1070

1071
  gst_alpha_init_params (alpha);
1072

1073
  return TRUE;
1074 1075
}

1076
static GstFlowReturn
1077
gst_alpha_transform (GstBaseTransform * btrans, GstBuffer * in, GstBuffer * out)
1078
{
1079 1080
  GstAlpha *alpha = GST_ALPHA (btrans);
  gint width, height;
1081
  GstClockTime timestamp;
1082

1083 1084
  width = alpha->width;
  height = alpha->height;
1085

1086 1087 1088 1089
  GST_BUFFER_TIMESTAMP (out) = GST_BUFFER_TIMESTAMP (in);
  GST_BUFFER_DURATION (out) = GST_BUFFER_DURATION (in);
  timestamp = gst_segment_to_stream_time (&btrans->segment, GST_FORMAT_TIME,
      GST_BUFFER_TIMESTAMP (in));
1090 1091 1092
  GST_LOG ("Got stream time of %" GST_TIME_FORMAT, GST_TIME_ARGS (timestamp));
  if (GST_CLOCK_TIME_IS_VALID (timestamp))
    gst_object_sync_values (G_OBJECT (alpha), timestamp);
1093

1094
  GST_OBJECT_LOCK (alpha);
1095 1096 1097 1098
  if (G_UNLIKELY (!alpha->process)) {
    GST_ERROR_OBJECT (alpha, "Not negotiated yet");
    GST_OBJECT_UNLOCK (alpha);
    return GST_FLOW_NOT_NEGOTIATED;
1099
  }
1100 1101 1102

  alpha->process (GST_BUFFER_DATA (in),
      GST_BUFFER_DATA (out), width, height, alpha);
1103
  GST_OBJECT_UNLOCK (alpha);
1104

1105
  return GST_FLOW_OK;
1106 1107 1108 1109 1110
}

static gboolean
plugin_init (GstPlugin * plugin)
{
1111 1112
  gst_controller_init (NULL, NULL);

1113 1114 1115 1116 1117 1118
  return gst_element_register (plugin, "alpha", GST_RANK_NONE, GST_TYPE_ALPHA);
}

GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
    GST_VERSION_MINOR,
    "alpha",
1119
    "adds an alpha channel to video - constant or via chroma-keying",
1120
    plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)