FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/v4l2_buffers.c
Date: 2021-09-22 23:55:11
Exec Total Coverage
Lines: 0 295 0.0%
Branches: 0 228 0.0%

Line Branch Exec Source
1 /*
2 * V4L2 buffer helper functions.
3 *
4 * Copyright (C) 2017 Alexis Ballier <aballier@gentoo.org>
5 * Copyright (C) 2017 Jorge Ramirez <jorge.ramirez-ortiz@linaro.org>
6 *
7 * This file is part of FFmpeg.
8 *
9 * FFmpeg is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2.1 of the License, or (at your option) any later version.
13 *
14 * FFmpeg is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with FFmpeg; if not, write to the Free Software
21 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22 */
23
24 #include <linux/videodev2.h>
25 #include <sys/ioctl.h>
26 #include <sys/mman.h>
27 #include <unistd.h>
28 #include <fcntl.h>
29 #include <poll.h>
30 #include "libavcodec/avcodec.h"
31 #include "libavcodec/internal.h"
32 #include "libavutil/pixdesc.h"
33 #include "v4l2_context.h"
34 #include "v4l2_buffers.h"
35 #include "v4l2_m2m.h"
36
37 #define USEC_PER_SEC 1000000
38 static AVRational v4l2_timebase = { 1, USEC_PER_SEC };
39
40 static inline V4L2m2mContext *buf_to_m2mctx(V4L2Buffer *buf)
41 {
42 return V4L2_TYPE_IS_OUTPUT(buf->context->type) ?
43 container_of(buf->context, V4L2m2mContext, output) :
44 container_of(buf->context, V4L2m2mContext, capture);
45 }
46
47 static inline AVCodecContext *logger(V4L2Buffer *buf)
48 {
49 return buf_to_m2mctx(buf)->avctx;
50 }
51
52 static inline AVRational v4l2_get_timebase(V4L2Buffer *avbuf)
53 {
54 V4L2m2mContext *s = buf_to_m2mctx(avbuf);
55
56 if (s->avctx->pkt_timebase.num)
57 return s->avctx->pkt_timebase;
58 return s->avctx->time_base;
59 }
60
61 static inline void v4l2_set_pts(V4L2Buffer *out, int64_t pts)
62 {
63 int64_t v4l2_pts;
64
65 if (pts == AV_NOPTS_VALUE)
66 pts = 0;
67
68 /* convert pts to v4l2 timebase */
69 v4l2_pts = av_rescale_q(pts, v4l2_get_timebase(out), v4l2_timebase);
70 out->buf.timestamp.tv_usec = v4l2_pts % USEC_PER_SEC;
71 out->buf.timestamp.tv_sec = v4l2_pts / USEC_PER_SEC;
72 }
73
74 static inline int64_t v4l2_get_pts(V4L2Buffer *avbuf)
75 {
76 int64_t v4l2_pts;
77
78 /* convert pts back to encoder timebase */
79 v4l2_pts = (int64_t)avbuf->buf.timestamp.tv_sec * USEC_PER_SEC +
80 avbuf->buf.timestamp.tv_usec;
81
82 return av_rescale_q(v4l2_pts, v4l2_timebase, v4l2_get_timebase(avbuf));
83 }
84
85 static enum AVColorPrimaries v4l2_get_color_primaries(V4L2Buffer *buf)
86 {
87 enum v4l2_ycbcr_encoding ycbcr;
88 enum v4l2_colorspace cs;
89
90 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
91 buf->context->format.fmt.pix_mp.colorspace :
92 buf->context->format.fmt.pix.colorspace;
93
94 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
95 buf->context->format.fmt.pix_mp.ycbcr_enc:
96 buf->context->format.fmt.pix.ycbcr_enc;
97
98 switch(ycbcr) {
99 case V4L2_YCBCR_ENC_XV709:
100 case V4L2_YCBCR_ENC_709: return AVCOL_PRI_BT709;
101 case V4L2_YCBCR_ENC_XV601:
102 case V4L2_YCBCR_ENC_601:return AVCOL_PRI_BT470M;
103 default:
104 break;
105 }
106
107 switch(cs) {
108 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_PRI_BT470BG;
109 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_PRI_SMPTE170M;
110 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_PRI_SMPTE240M;
111 case V4L2_COLORSPACE_BT2020: return AVCOL_PRI_BT2020;
112 default:
113 break;
114 }
115
116 return AVCOL_PRI_UNSPECIFIED;
117 }
118
119 static enum AVColorRange v4l2_get_color_range(V4L2Buffer *buf)
120 {
121 enum v4l2_quantization qt;
122
123 qt = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
124 buf->context->format.fmt.pix_mp.quantization :
125 buf->context->format.fmt.pix.quantization;
126
127 switch (qt) {
128 case V4L2_QUANTIZATION_LIM_RANGE: return AVCOL_RANGE_MPEG;
129 case V4L2_QUANTIZATION_FULL_RANGE: return AVCOL_RANGE_JPEG;
130 default:
131 break;
132 }
133
134 return AVCOL_RANGE_UNSPECIFIED;
135 }
136
137 static enum AVColorSpace v4l2_get_color_space(V4L2Buffer *buf)
138 {
139 enum v4l2_ycbcr_encoding ycbcr;
140 enum v4l2_colorspace cs;
141
142 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
143 buf->context->format.fmt.pix_mp.colorspace :
144 buf->context->format.fmt.pix.colorspace;
145
146 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
147 buf->context->format.fmt.pix_mp.ycbcr_enc:
148 buf->context->format.fmt.pix.ycbcr_enc;
149
150 switch(cs) {
151 case V4L2_COLORSPACE_SRGB: return AVCOL_SPC_RGB;
152 case V4L2_COLORSPACE_REC709: return AVCOL_SPC_BT709;
153 case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_SPC_FCC;
154 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_SPC_BT470BG;
155 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_SPC_SMPTE170M;
156 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_SPC_SMPTE240M;
157 case V4L2_COLORSPACE_BT2020:
158 if (ycbcr == V4L2_YCBCR_ENC_BT2020_CONST_LUM)
159 return AVCOL_SPC_BT2020_CL;
160 else
161 return AVCOL_SPC_BT2020_NCL;
162 default:
163 break;
164 }
165
166 return AVCOL_SPC_UNSPECIFIED;
167 }
168
169 static enum AVColorTransferCharacteristic v4l2_get_color_trc(V4L2Buffer *buf)
170 {
171 enum v4l2_ycbcr_encoding ycbcr;
172 enum v4l2_xfer_func xfer;
173 enum v4l2_colorspace cs;
174
175 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
176 buf->context->format.fmt.pix_mp.colorspace :
177 buf->context->format.fmt.pix.colorspace;
178
179 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
180 buf->context->format.fmt.pix_mp.ycbcr_enc:
181 buf->context->format.fmt.pix.ycbcr_enc;
182
183 xfer = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
184 buf->context->format.fmt.pix_mp.xfer_func:
185 buf->context->format.fmt.pix.xfer_func;
186
187 switch (xfer) {
188 case V4L2_XFER_FUNC_709: return AVCOL_TRC_BT709;
189 case V4L2_XFER_FUNC_SRGB: return AVCOL_TRC_IEC61966_2_1;
190 default:
191 break;
192 }
193
194 switch (cs) {
195 case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_TRC_GAMMA22;
196 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_TRC_GAMMA28;
197 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_TRC_SMPTE170M;
198 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_TRC_SMPTE240M;
199 default:
200 break;
201 }
202
203 switch (ycbcr) {
204 case V4L2_YCBCR_ENC_XV709:
205 case V4L2_YCBCR_ENC_XV601: return AVCOL_TRC_BT1361_ECG;
206 default:
207 break;
208 }
209
210 return AVCOL_TRC_UNSPECIFIED;
211 }
212
213 static void v4l2_free_buffer(void *opaque, uint8_t *unused)
214 {
215 V4L2Buffer* avbuf = opaque;
216 V4L2m2mContext *s = buf_to_m2mctx(avbuf);
217
218 if (atomic_fetch_sub(&avbuf->context_refcount, 1) == 1) {
219 atomic_fetch_sub_explicit(&s->refcount, 1, memory_order_acq_rel);
220
221 if (s->reinit) {
222 if (!atomic_load(&s->refcount))
223 sem_post(&s->refsync);
224 } else {
225 if (s->draining && V4L2_TYPE_IS_OUTPUT(avbuf->context->type)) {
226 /* no need to queue more buffers to the driver */
227 avbuf->status = V4L2BUF_AVAILABLE;
228 }
229 else if (avbuf->context->streamon)
230 ff_v4l2_buffer_enqueue(avbuf);
231 }
232
233 av_buffer_unref(&avbuf->context_ref);
234 }
235 }
236
237 static int v4l2_buf_increase_ref(V4L2Buffer *in)
238 {
239 V4L2m2mContext *s = buf_to_m2mctx(in);
240
241 if (in->context_ref)
242 atomic_fetch_add(&in->context_refcount, 1);
243 else {
244 in->context_ref = av_buffer_ref(s->self_ref);
245 if (!in->context_ref)
246 return AVERROR(ENOMEM);
247
248 in->context_refcount = 1;
249 }
250
251 in->status = V4L2BUF_RET_USER;
252 atomic_fetch_add_explicit(&s->refcount, 1, memory_order_relaxed);
253
254 return 0;
255 }
256
257 static int v4l2_buf_to_bufref(V4L2Buffer *in, int plane, AVBufferRef **buf)
258 {
259 int ret;
260
261 if (plane >= in->num_planes)
262 return AVERROR(EINVAL);
263
264 /* even though most encoders return 0 in data_offset encoding vp8 does require this value */
265 *buf = av_buffer_create((char *)in->plane_info[plane].mm_addr + in->planes[plane].data_offset,
266 in->plane_info[plane].length, v4l2_free_buffer, in, 0);
267 if (!*buf)
268 return AVERROR(ENOMEM);
269
270 ret = v4l2_buf_increase_ref(in);
271 if (ret)
272 av_buffer_unref(buf);
273
274 return ret;
275 }
276
277 static int v4l2_bufref_to_buf(V4L2Buffer *out, int plane, const uint8_t* data, int size, int offset)
278 {
279 unsigned int bytesused, length;
280
281 if (plane >= out->num_planes)
282 return AVERROR(EINVAL);
283
284 length = out->plane_info[plane].length;
285 bytesused = FFMIN(size+offset, length);
286
287 memcpy((uint8_t*)out->plane_info[plane].mm_addr+offset, data, FFMIN(size, length-offset));
288
289 if (V4L2_TYPE_IS_MULTIPLANAR(out->buf.type)) {
290 out->planes[plane].bytesused = bytesused;
291 out->planes[plane].length = length;
292 } else {
293 out->buf.bytesused = bytesused;
294 out->buf.length = length;
295 }
296
297 return 0;
298 }
299
300 static int v4l2_buffer_buf_to_swframe(AVFrame *frame, V4L2Buffer *avbuf)
301 {
302 int i, ret;
303
304 frame->format = avbuf->context->av_pix_fmt;
305
306 for (i = 0; i < avbuf->num_planes; i++) {
307 ret = v4l2_buf_to_bufref(avbuf, i, &frame->buf[i]);
308 if (ret)
309 return ret;
310
311 frame->linesize[i] = avbuf->plane_info[i].bytesperline;
312 frame->data[i] = frame->buf[i]->data;
313 }
314
315 /* fixup special cases */
316 switch (avbuf->context->av_pix_fmt) {
317 case AV_PIX_FMT_NV12:
318 case AV_PIX_FMT_NV21:
319 if (avbuf->num_planes > 1)
320 break;
321 frame->linesize[1] = avbuf->plane_info[0].bytesperline;
322 frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
323 break;
324
325 case AV_PIX_FMT_YUV420P:
326 if (avbuf->num_planes > 1)
327 break;
328 frame->linesize[1] = avbuf->plane_info[0].bytesperline >> 1;
329 frame->linesize[2] = avbuf->plane_info[0].bytesperline >> 1;
330 frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
331 frame->data[2] = frame->data[1] + ((avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height) >> 2);
332 break;
333
334 default:
335 break;
336 }
337
338 return 0;
339 }
340
341 static int v4l2_buffer_swframe_to_buf(const AVFrame *frame, V4L2Buffer *out)
342 {
343 int i, ret;
344 struct v4l2_format fmt = out->context->format;
345 int pixel_format = V4L2_TYPE_IS_MULTIPLANAR(fmt.type) ?
346 fmt.fmt.pix_mp.pixelformat : fmt.fmt.pix.pixelformat;
347 int height = V4L2_TYPE_IS_MULTIPLANAR(fmt.type) ?
348 fmt.fmt.pix_mp.height : fmt.fmt.pix.height;
349 int is_planar_format = 0;
350
351 switch (pixel_format) {
352 case V4L2_PIX_FMT_YUV420M:
353 case V4L2_PIX_FMT_YVU420M:
354 #ifdef V4L2_PIX_FMT_YUV422M
355 case V4L2_PIX_FMT_YUV422M:
356 #endif
357 #ifdef V4L2_PIX_FMT_YVU422M
358 case V4L2_PIX_FMT_YVU422M:
359 #endif
360 #ifdef V4L2_PIX_FMT_YUV444M
361 case V4L2_PIX_FMT_YUV444M:
362 #endif
363 #ifdef V4L2_PIX_FMT_YVU444M
364 case V4L2_PIX_FMT_YVU444M:
365 #endif
366 case V4L2_PIX_FMT_NV12M:
367 case V4L2_PIX_FMT_NV21M:
368 case V4L2_PIX_FMT_NV12MT_16X16:
369 case V4L2_PIX_FMT_NV12MT:
370 case V4L2_PIX_FMT_NV16M:
371 case V4L2_PIX_FMT_NV61M:
372 is_planar_format = 1;
373 }
374
375 if (!is_planar_format) {
376 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(frame->format);
377 int planes_nb = 0;
378 int offset = 0;
379
380 for (i = 0; i < desc->nb_components; i++)
381 planes_nb = FFMAX(planes_nb, desc->comp[i].plane + 1);
382
383 for (i = 0; i < planes_nb; i++) {
384 int size, h = height;
385 if (i == 1 || i == 2) {
386 h = AV_CEIL_RSHIFT(h, desc->log2_chroma_h);
387 }
388 size = frame->linesize[i] * h;
389 ret = v4l2_bufref_to_buf(out, 0, frame->data[i], size, offset);
390 if (ret)
391 return ret;
392 offset += size;
393 }
394 return 0;
395 }
396
397 for (i = 0; i < out->num_planes; i++) {
398 ret = v4l2_bufref_to_buf(out, i, frame->buf[i]->data, frame->buf[i]->size, 0);
399 if (ret)
400 return ret;
401 }
402
403 return 0;
404 }
405
406 /******************************************************************************
407 *
408 * V4L2Buffer interface
409 *
410 ******************************************************************************/
411
412 int ff_v4l2_buffer_avframe_to_buf(const AVFrame *frame, V4L2Buffer *out)
413 {
414 v4l2_set_pts(out, frame->pts);
415
416 return v4l2_buffer_swframe_to_buf(frame, out);
417 }
418
419 int ff_v4l2_buffer_buf_to_avframe(AVFrame *frame, V4L2Buffer *avbuf)
420 {
421 int ret;
422
423 av_frame_unref(frame);
424
425 /* 1. get references to the actual data */
426 ret = v4l2_buffer_buf_to_swframe(frame, avbuf);
427 if (ret)
428 return ret;
429
430 /* 2. get frame information */
431 frame->key_frame = !!(avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME);
432 frame->color_primaries = v4l2_get_color_primaries(avbuf);
433 frame->colorspace = v4l2_get_color_space(avbuf);
434 frame->color_range = v4l2_get_color_range(avbuf);
435 frame->color_trc = v4l2_get_color_trc(avbuf);
436 frame->pts = v4l2_get_pts(avbuf);
437 frame->pkt_dts = AV_NOPTS_VALUE;
438
439 /* these values are updated also during re-init in v4l2_process_driver_event */
440 frame->height = avbuf->context->height;
441 frame->width = avbuf->context->width;
442 frame->sample_aspect_ratio = avbuf->context->sample_aspect_ratio;
443
444 /* 3. report errors upstream */
445 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
446 av_log(logger(avbuf), AV_LOG_ERROR, "%s: driver decode error\n", avbuf->context->name);
447 frame->decode_error_flags |= FF_DECODE_ERROR_INVALID_BITSTREAM;
448 }
449
450 return 0;
451 }
452
453 int ff_v4l2_buffer_buf_to_avpkt(AVPacket *pkt, V4L2Buffer *avbuf)
454 {
455 int ret;
456
457 av_packet_unref(pkt);
458 ret = v4l2_buf_to_bufref(avbuf, 0, &pkt->buf);
459 if (ret)
460 return ret;
461
462 pkt->size = V4L2_TYPE_IS_MULTIPLANAR(avbuf->buf.type) ? avbuf->buf.m.planes[0].bytesused : avbuf->buf.bytesused;
463 pkt->data = pkt->buf->data;
464
465 if (avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME)
466 pkt->flags |= AV_PKT_FLAG_KEY;
467
468 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
469 av_log(logger(avbuf), AV_LOG_ERROR, "%s driver encode error\n", avbuf->context->name);
470 pkt->flags |= AV_PKT_FLAG_CORRUPT;
471 }
472
473 pkt->dts = pkt->pts = v4l2_get_pts(avbuf);
474
475 return 0;
476 }
477
478 int ff_v4l2_buffer_avpkt_to_buf(const AVPacket *pkt, V4L2Buffer *out)
479 {
480 int ret;
481
482 ret = v4l2_bufref_to_buf(out, 0, pkt->data, pkt->size, 0);
483 if (ret)
484 return ret;
485
486 v4l2_set_pts(out, pkt->pts);
487
488 if (pkt->flags & AV_PKT_FLAG_KEY)
489 out->flags = V4L2_BUF_FLAG_KEYFRAME;
490
491 return 0;
492 }
493
494 int ff_v4l2_buffer_initialize(V4L2Buffer* avbuf, int index)
495 {
496 V4L2Context *ctx = avbuf->context;
497 int ret, i;
498
499 avbuf->buf.memory = V4L2_MEMORY_MMAP;
500 avbuf->buf.type = ctx->type;
501 avbuf->buf.index = index;
502
503 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
504 avbuf->buf.length = VIDEO_MAX_PLANES;
505 avbuf->buf.m.planes = avbuf->planes;
506 }
507
508 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QUERYBUF, &avbuf->buf);
509 if (ret < 0)
510 return AVERROR(errno);
511
512 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
513 avbuf->num_planes = 0;
514 /* in MP, the V4L2 API states that buf.length means num_planes */
515 for (i = 0; i < avbuf->buf.length; i++) {
516 if (avbuf->buf.m.planes[i].length)
517 avbuf->num_planes++;
518 }
519 } else
520 avbuf->num_planes = 1;
521
522 for (i = 0; i < avbuf->num_planes; i++) {
523
524 avbuf->plane_info[i].bytesperline = V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ?
525 ctx->format.fmt.pix_mp.plane_fmt[i].bytesperline :
526 ctx->format.fmt.pix.bytesperline;
527
528 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
529 avbuf->plane_info[i].length = avbuf->buf.m.planes[i].length;
530 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.m.planes[i].length,
531 PROT_READ | PROT_WRITE, MAP_SHARED,
532 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.planes[i].m.mem_offset);
533 } else {
534 avbuf->plane_info[i].length = avbuf->buf.length;
535 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.length,
536 PROT_READ | PROT_WRITE, MAP_SHARED,
537 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.offset);
538 }
539
540 if (avbuf->plane_info[i].mm_addr == MAP_FAILED)
541 return AVERROR(ENOMEM);
542 }
543
544 avbuf->status = V4L2BUF_AVAILABLE;
545
546 if (V4L2_TYPE_IS_OUTPUT(ctx->type))
547 return 0;
548
549 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
550 avbuf->buf.m.planes = avbuf->planes;
551 avbuf->buf.length = avbuf->num_planes;
552
553 } else {
554 avbuf->buf.bytesused = avbuf->planes[0].bytesused;
555 avbuf->buf.length = avbuf->planes[0].length;
556 }
557
558 return ff_v4l2_buffer_enqueue(avbuf);
559 }
560
561 int ff_v4l2_buffer_enqueue(V4L2Buffer* avbuf)
562 {
563 int ret;
564
565 avbuf->buf.flags = avbuf->flags;
566
567 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QBUF, &avbuf->buf);
568 if (ret < 0)
569 return AVERROR(errno);
570
571 avbuf->status = V4L2BUF_IN_DRIVER;
572
573 return 0;
574 }
575