1 /*
2 * GStreamer
3 * Copyright (C) 2019 Mathieu Duponchelle <mathieu@centricular.com>
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
14 *
15 * You should have received a copy of the GNU Library General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
18 * Boston, MA 02110-1301, USA.
19 */
20
21 /**
22 * SECTION:element-line21encoder
23 * @title: line21encoder
24 *
25 */
26
27 #ifdef HAVE_CONFIG_H
28 # include <config.h>
29 #endif
30
31 #include <gst/gst.h>
32 #include <gst/base/base.h>
33 #include <gst/video/video.h>
34 #include <string.h>
35
36 #include "gstline21enc.h"
37 #include "io-sim.h"
38
39 GST_DEBUG_CATEGORY_STATIC (gst_line_21_encoder_debug);
40 #define GST_CAT_DEFAULT gst_line_21_encoder_debug
41
42 enum
43 {
44 PROP_0,
45 PROP_REMOVE_CAPTION_META,
46 };
47
48 /* FIXME: add and test support for PAL resolutions */
49 #define CAPS "video/x-raw, format={ I420, YUY2, YVYU, UYVY, VYUY }, width=(int)720, height=(int){ 525, 486 }, interlace-mode=interleaved"
50
51 static GstStaticPadTemplate sinktemplate = GST_STATIC_PAD_TEMPLATE ("sink",
52 GST_PAD_SINK,
53 GST_PAD_ALWAYS,
54 GST_STATIC_CAPS (CAPS));
55
56 static GstStaticPadTemplate srctemplate = GST_STATIC_PAD_TEMPLATE ("src",
57 GST_PAD_SRC,
58 GST_PAD_ALWAYS,
59 GST_STATIC_CAPS (CAPS));
60
61 G_DEFINE_TYPE (GstLine21Encoder, gst_line_21_encoder, GST_TYPE_VIDEO_FILTER);
62 #define parent_class gst_line_21_encoder_parent_class
63 GST_ELEMENT_REGISTER_DEFINE (line21encoder, "line21encoder",
64 GST_RANK_NONE, GST_TYPE_LINE21ENCODER);
65
66 static gboolean gst_line_21_encoder_set_info (GstVideoFilter * filter,
67 GstCaps * incaps, GstVideoInfo * in_info,
68 GstCaps * outcaps, GstVideoInfo * out_info);
69 static GstFlowReturn gst_line_21_encoder_transform_ip (GstVideoFilter * filter,
70 GstVideoFrame * frame);
71 static void gst_line_21_encoder_set_property (GObject * self, guint prop_id,
72 const GValue * value, GParamSpec * pspec);
73 static void gst_line_21_encoder_get_property (GObject * self, guint prop_id,
74 GValue * value, GParamSpec * pspec);
75
76
77 static void
gst_line_21_encoder_class_init(GstLine21EncoderClass * klass)78 gst_line_21_encoder_class_init (GstLine21EncoderClass * klass)
79 {
80 GObjectClass *gobject_class;
81 GstElementClass *gstelement_class;
82 GstVideoFilterClass *filter_class;
83
84 gobject_class = (GObjectClass *) klass;
85 gstelement_class = (GstElementClass *) klass;
86 filter_class = (GstVideoFilterClass *) klass;
87
88 gobject_class->set_property = gst_line_21_encoder_set_property;
89 gobject_class->get_property = gst_line_21_encoder_get_property;
90
91 /**
92 * line21encoder:remove-caption-meta
93 *
94 * Selects whether the encoded #GstVideoCaptionMeta should be removed from
95 * the outgoing video buffers or whether it should be kept.
96 *
97 * Since: 1.20
98 */
99 g_object_class_install_property (G_OBJECT_CLASS (klass),
100 PROP_REMOVE_CAPTION_META, g_param_spec_boolean ("remove-caption-meta",
101 "Remove Caption Meta",
102 "Remove encoded caption meta from outgoing video buffers", FALSE,
103 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
104
105
106 gst_element_class_set_static_metadata (gstelement_class,
107 "Line 21 CC Encoder",
108 "Filter/Video/ClosedCaption",
109 "Inject line21 CC in SD video streams",
110 "Mathieu Duponchelle <mathieu@centricular.com>");
111
112 gst_element_class_add_static_pad_template (gstelement_class, &sinktemplate);
113 gst_element_class_add_static_pad_template (gstelement_class, &srctemplate);
114
115 filter_class->set_info = gst_line_21_encoder_set_info;
116 filter_class->transform_frame_ip = gst_line_21_encoder_transform_ip;
117
118 GST_DEBUG_CATEGORY_INIT (gst_line_21_encoder_debug, "line21encoder",
119 0, "Line 21 CC Encoder");
120 vbi_initialize_gst_debug ();
121 }
122
123 static void
gst_line_21_encoder_init(GstLine21Encoder * filter)124 gst_line_21_encoder_init (GstLine21Encoder * filter)
125 {
126 }
127
128 static void
gst_line_21_encoder_set_property(GObject * object,guint prop_id,const GValue * value,GParamSpec * pspec)129 gst_line_21_encoder_set_property (GObject * object, guint prop_id,
130 const GValue * value, GParamSpec * pspec)
131 {
132 GstLine21Encoder *enc = GST_LINE21ENCODER (object);
133
134 switch (prop_id) {
135 case PROP_REMOVE_CAPTION_META:
136 enc->remove_caption_meta = g_value_get_boolean (value);
137 break;
138 default:
139 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
140 break;
141 }
142 }
143
144 static void
gst_line_21_encoder_get_property(GObject * object,guint prop_id,GValue * value,GParamSpec * pspec)145 gst_line_21_encoder_get_property (GObject * object, guint prop_id,
146 GValue * value, GParamSpec * pspec)
147 {
148 GstLine21Encoder *enc = GST_LINE21ENCODER (object);
149
150 switch (prop_id) {
151 case PROP_REMOVE_CAPTION_META:
152 g_value_set_boolean (value, enc->remove_caption_meta);
153 break;
154 default:
155 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
156 break;
157 }
158 }
159
160 static vbi_pixfmt
vbi_pixfmt_from_gst_video_format(GstVideoFormat format)161 vbi_pixfmt_from_gst_video_format (GstVideoFormat format)
162 {
163 switch (format) {
164 case GST_VIDEO_FORMAT_I420:
165 return VBI_PIXFMT_YUV420;
166 case GST_VIDEO_FORMAT_YUY2:
167 return VBI_PIXFMT_YUYV;
168 case GST_VIDEO_FORMAT_YVYU:
169 return VBI_PIXFMT_YVYU;
170 case GST_VIDEO_FORMAT_UYVY:
171 return VBI_PIXFMT_UYVY;
172 case GST_VIDEO_FORMAT_VYUY:
173 return VBI_PIXFMT_VYUY;
174 default:
175 g_assert_not_reached ();
176 return (vbi_pixfmt) 0;
177 }
178 #undef NATIVE_VBI_FMT
179 }
180
181 static gboolean
gst_line_21_encoder_set_info(GstVideoFilter * filter,GstCaps * incaps,GstVideoInfo * in_info,GstCaps * outcaps,GstVideoInfo * out_info)182 gst_line_21_encoder_set_info (GstVideoFilter * filter,
183 GstCaps * incaps, GstVideoInfo * in_info,
184 GstCaps * outcaps, GstVideoInfo * out_info)
185 {
186 GstLine21Encoder *self = GST_LINE21ENCODER (filter);
187
188 self->info = *in_info;
189
190 /*
191 * Set up blank / black / white levels fit for NTSC, no actual relation
192 * with the height of the video
193 */
194 self->sp.scanning = 525;
195 /* The pixel format */
196 self->sp.sampling_format =
197 vbi_pixfmt_from_gst_video_format (GST_VIDEO_INFO_FORMAT (&self->info));
198 /* Sampling rate. For BT.601 it's 13.5MHz */
199 self->sp.sampling_rate = 13.5e6;
200 /* Stride */
201 self->sp.bytes_per_line = GST_VIDEO_INFO_COMP_STRIDE (&self->info, 0);
202 /* Horizontal offset of the VBI image */
203 self->sp.offset = 122;
204
205 /* FIXME: magic numbers */
206 self->sp.start[0] = 21;
207 self->sp.count[0] = 1;
208 self->sp.start[1] = 284;
209 self->sp.count[1] = 1;
210
211 self->sp.interlaced = FALSE;
212 self->sp.synchronous = TRUE;
213
214 return TRUE;
215 }
216
217 #define MAX_CDP_PACKET_LEN 256
218 #define MAX_CEA608_LEN 32
219
220 /* Converts CDP into raw CEA708 cc_data, taken from ccconverter */
221 static guint
convert_cea708_cdp_cea708_cc_data_internal(GstLine21Encoder * self,const guint8 * cdp,guint cdp_len,guint8 cc_data[256])222 convert_cea708_cdp_cea708_cc_data_internal (GstLine21Encoder * self,
223 const guint8 * cdp, guint cdp_len, guint8 cc_data[256])
224 {
225 GstByteReader br;
226 guint16 u16;
227 guint8 u8;
228 guint8 flags;
229 guint len = 0;
230
231 /* Header + footer length */
232 if (cdp_len < 11) {
233 GST_WARNING_OBJECT (self, "cdp packet too short (%u). expected at "
234 "least %u", cdp_len, 11);
235 return 0;
236 }
237
238 gst_byte_reader_init (&br, cdp, cdp_len);
239 u16 = gst_byte_reader_get_uint16_be_unchecked (&br);
240 if (u16 != 0x9669) {
241 GST_WARNING_OBJECT (self, "cdp packet does not have initial magic bytes "
242 "of 0x9669");
243 return 0;
244 }
245
246 u8 = gst_byte_reader_get_uint8_unchecked (&br);
247 if (u8 != cdp_len) {
248 GST_WARNING_OBJECT (self, "cdp packet length (%u) does not match passed "
249 "in value (%u)", u8, cdp_len);
250 return 0;
251 }
252
253 gst_byte_reader_skip_unchecked (&br, 1);
254
255 flags = gst_byte_reader_get_uint8_unchecked (&br);
256 /* No cc_data? */
257 if ((flags & 0x40) == 0) {
258 GST_DEBUG_OBJECT (self, "cdp packet does have any cc_data");
259 return 0;
260 }
261
262 /* cdp_hdr_sequence_cntr */
263 gst_byte_reader_skip_unchecked (&br, 2);
264
265 /* time_code_present */
266 if (flags & 0x80) {
267 if (gst_byte_reader_get_remaining (&br) < 5) {
268 GST_WARNING_OBJECT (self, "cdp packet does not have enough data to "
269 "contain a timecode (%u). Need at least 5 bytes",
270 gst_byte_reader_get_remaining (&br));
271 return 0;
272 }
273
274 gst_byte_reader_skip_unchecked (&br, 5);
275 }
276
277 /* ccdata_present */
278 if (flags & 0x40) {
279 guint8 cc_count;
280
281 if (gst_byte_reader_get_remaining (&br) < 2) {
282 GST_WARNING_OBJECT (self, "not enough data to contain valid cc_data");
283 return 0;
284 }
285 u8 = gst_byte_reader_get_uint8_unchecked (&br);
286 if (u8 != 0x72) {
287 GST_WARNING_OBJECT (self, "missing cc_data start code of 0x72, "
288 "found 0x%02x", u8);
289 return 0;
290 }
291
292 cc_count = gst_byte_reader_get_uint8_unchecked (&br);
293 if ((cc_count & 0xe0) != 0xe0) {
294 GST_WARNING_OBJECT (self, "reserved bits are not 0xe0, found 0x%02x", u8);
295 return 0;
296 }
297 cc_count &= 0x1f;
298
299 len = 3 * cc_count;
300 if (gst_byte_reader_get_remaining (&br) < len)
301 return 0;
302
303 memcpy (cc_data, gst_byte_reader_get_data_unchecked (&br, len), len);
304 }
305
306 /* skip everything else we don't care about */
307 return len;
308 }
309
310 #define VAL_OR_0(v) ((v) ? (*(v)) : 0)
311
312 static guint
compact_cc_data(guint8 * cc_data,guint cc_data_len)313 compact_cc_data (guint8 * cc_data, guint cc_data_len)
314 {
315 gboolean started_ccp = FALSE;
316 guint out_len = 0;
317 guint i;
318
319 if (cc_data_len % 3 != 0) {
320 GST_WARNING ("Invalid cc_data buffer size");
321 cc_data_len = cc_data_len - (cc_data_len % 3);
322 }
323
324 for (i = 0; i < cc_data_len / 3; i++) {
325 gboolean cc_valid = (cc_data[i * 3] & 0x04) == 0x04;
326 guint8 cc_type = cc_data[i * 3] & 0x03;
327
328 if (!started_ccp && (cc_type == 0x00 || cc_type == 0x01)) {
329 if (cc_valid) {
330 /* copy over valid 608 data */
331 cc_data[out_len++] = cc_data[i * 3];
332 cc_data[out_len++] = cc_data[i * 3 + 1];
333 cc_data[out_len++] = cc_data[i * 3 + 2];
334 }
335 continue;
336 }
337
338 if (cc_type & 0x10)
339 started_ccp = TRUE;
340
341 if (!cc_valid)
342 continue;
343
344 if (cc_type == 0x00 || cc_type == 0x01) {
345 GST_WARNING ("Invalid cc_data. cea608 bytes after cea708");
346 return 0;
347 }
348
349 cc_data[out_len++] = cc_data[i * 3];
350 cc_data[out_len++] = cc_data[i * 3 + 1];
351 cc_data[out_len++] = cc_data[i * 3 + 2];
352 }
353
354 GST_LOG ("compacted cc_data from %u to %u", cc_data_len, out_len);
355
356 return out_len;
357 }
358
359 static gint
cc_data_extract_cea608(guint8 * cc_data,guint cc_data_len,guint8 * cea608_field1,guint * cea608_field1_len,guint8 * cea608_field2,guint * cea608_field2_len)360 cc_data_extract_cea608 (guint8 * cc_data, guint cc_data_len,
361 guint8 * cea608_field1, guint * cea608_field1_len,
362 guint8 * cea608_field2, guint * cea608_field2_len)
363 {
364 guint i, field_1_len = 0, field_2_len = 0;
365
366 if (cea608_field1_len) {
367 field_1_len = *cea608_field1_len;
368 *cea608_field1_len = 0;
369 }
370 if (cea608_field2_len) {
371 field_2_len = *cea608_field2_len;
372 *cea608_field2_len = 0;
373 }
374
375 if (cc_data_len % 3 != 0) {
376 GST_WARNING ("Invalid cc_data buffer size %u. Truncating to a multiple "
377 "of 3", cc_data_len);
378 cc_data_len = cc_data_len - (cc_data_len % 3);
379 }
380
381 for (i = 0; i < cc_data_len / 3; i++) {
382 gboolean cc_valid = (cc_data[i * 3] & 0x04) == 0x04;
383 guint8 cc_type = cc_data[i * 3] & 0x03;
384
385 GST_TRACE ("0x%02x 0x%02x 0x%02x, valid: %u, type: 0b%u%u",
386 cc_data[i * 3 + 0], cc_data[i * 3 + 1], cc_data[i * 3 + 2], cc_valid,
387 cc_type & 0x2, cc_type & 0x1);
388
389 if (cc_type == 0x00) {
390 if (!cc_valid)
391 continue;
392
393 if (cea608_field1 && cea608_field1_len) {
394 if (*cea608_field1_len + 2 > field_1_len) {
395 GST_WARNING ("Too many cea608 input bytes %u for field 1",
396 *cea608_field1_len + 2);
397 return -1;
398 }
399 cea608_field1[(*cea608_field1_len)++] = cc_data[i * 3 + 1];
400 cea608_field1[(*cea608_field1_len)++] = cc_data[i * 3 + 2];
401 }
402 } else if (cc_type == 0x01) {
403 if (!cc_valid)
404 continue;
405
406 if (cea608_field2 && cea608_field2_len) {
407 if (*cea608_field2_len + 2 > field_2_len) {
408 GST_WARNING ("Too many cea608 input bytes %u for field 2",
409 *cea608_field2_len + 2);
410 return -1;
411 }
412 cea608_field2[(*cea608_field2_len)++] = cc_data[i * 3 + 1];
413 cea608_field2[(*cea608_field2_len)++] = cc_data[i * 3 + 2];
414 }
415 } else {
416 /* all cea608 packets must be at the beginning of a cc_data */
417 break;
418 }
419 }
420
421 g_assert_cmpint (i * 3, <=, cc_data_len);
422
423 GST_LOG ("Extracted cea608-1 of length %u and cea608-2 of length %u",
424 VAL_OR_0 (cea608_field1_len), VAL_OR_0 (cea608_field2_len));
425
426 return i * 3;
427 }
428
429 static GstFlowReturn
gst_line_21_encoder_transform_ip(GstVideoFilter * filter,GstVideoFrame * frame)430 gst_line_21_encoder_transform_ip (GstVideoFilter * filter,
431 GstVideoFrame * frame)
432 {
433 GstLine21Encoder *self = GST_LINE21ENCODER (filter);
434 GstVideoCaptionMeta *cc_meta;
435 guint8 *buf;
436 vbi_sliced sliced[2];
437 gpointer iter = NULL;
438 GstFlowReturn ret = GST_FLOW_ERROR;
439 guint offset;
440
441 sliced[0].id = VBI_SLICED_CAPTION_525_F1;
442 sliced[0].line = self->sp.start[0];
443 sliced[1].id = VBI_SLICED_CAPTION_525_F2;
444 sliced[1].line = self->sp.start[1];
445
446 sliced[0].data[0] = 0x80;
447 sliced[0].data[1] = 0x80;
448 sliced[1].data[0] = 0x80;
449 sliced[1].data[1] = 0x80;
450
451 /* We loop over caption metas until we find the first CEA608 meta */
452 while ((cc_meta = (GstVideoCaptionMeta *)
453 gst_buffer_iterate_meta_filtered (frame->buffer, &iter,
454 GST_VIDEO_CAPTION_META_API_TYPE))) {
455 guint n = cc_meta->size;
456 guint i;
457
458 if (cc_meta->caption_type == GST_VIDEO_CAPTION_TYPE_CEA708_CDP) {
459 guint8 cc_data[MAX_CDP_PACKET_LEN];
460 guint8 cea608_field1[MAX_CEA608_LEN];
461 guint8 cea608_field2[MAX_CEA608_LEN];
462 guint cea608_field1_len = MAX_CEA608_LEN;
463 guint cea608_field2_len = MAX_CEA608_LEN;
464 guint cc_data_len = 0;
465
466 cc_data_len =
467 convert_cea708_cdp_cea708_cc_data_internal (self, cc_meta->data,
468 cc_meta->size, cc_data);
469
470 cc_data_len = compact_cc_data (cc_data, cc_data_len);
471
472 cc_data_extract_cea608 (cc_data, cc_data_len,
473 cea608_field1, &cea608_field1_len, cea608_field2, &cea608_field2_len);
474
475 if (cea608_field1_len == 2) {
476 sliced[0].data[0] = cea608_field1[0];
477 sliced[0].data[1] = cea608_field1[1];
478 }
479
480 if (cea608_field2_len == 2) {
481 sliced[1].data[0] = cea608_field2[0];
482 sliced[1].data[1] = cea608_field2[1];
483 }
484
485 break;
486 } else if (cc_meta->caption_type == GST_VIDEO_CAPTION_TYPE_CEA608_S334_1A) {
487 if (n % 3 != 0) {
488 GST_ERROR_OBJECT (filter, "Invalid S334-1A CEA608 buffer size");
489 goto done;
490 }
491
492 n /= 3;
493
494 if (n >= 3) {
495 GST_ERROR_OBJECT (filter, "Too many S334-1A CEA608 triplets %u", n);
496 goto done;
497 }
498
499 for (i = 0; i < n; i++) {
500 if (cc_meta->data[i * 3] & 0x80) {
501 sliced[0].data[0] = cc_meta->data[i * 3 + 1];
502 sliced[0].data[1] = cc_meta->data[i * 3 + 2];
503 } else {
504 sliced[1].data[0] = cc_meta->data[i * 3 + 1];
505 sliced[1].data[1] = cc_meta->data[i * 3 + 2];
506 }
507 }
508
509 break;
510 }
511 }
512
513 /* We've encoded this meta, it can now be removed if required */
514 if (cc_meta && self->remove_caption_meta)
515 gst_buffer_remove_meta (frame->buffer, (GstMeta *) cc_meta);
516
517 /* When dealing with standard NTSC resolution, field 1 goes at line 21,
518 * when dealing with a reduced height the image has 3 VBI lines at the
519 * top and 3 at the bottom, and field 1 goes at line 1 */
520 offset = self->info.height == 525 ? 21 : 1;
521
522 buf =
523 (guint8 *) GST_VIDEO_FRAME_PLANE_DATA (frame,
524 0) + offset * GST_VIDEO_INFO_COMP_STRIDE (&self->info, 0);
525
526 if (!vbi_raw_video_image (buf, GST_VIDEO_INFO_COMP_STRIDE (&self->info,
527 0) * 2, &self->sp, 0, 0, 0, 0x000000FF, 0, sliced, 2)) {
528 GST_ERROR_OBJECT (filter, "Failed to encode CC data");
529 goto done;
530 }
531
532 ret = GST_FLOW_OK;
533
534 done:
535 return ret;
536 }
537