FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/v4l2_buffers.c
Date: 2024-07-24 19:24:46
Exec Total Coverage
Lines: 0 296 0.0%
Functions: 0 21 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 "libavutil/pixdesc.h"
32 #include "refstruct.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 ff_refstruct_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 = ff_refstruct_ref(s->self_ref);
245
246 in->context_refcount = 1;
247 }
248
249 in->status = V4L2BUF_RET_USER;
250 atomic_fetch_add_explicit(&s->refcount, 1, memory_order_relaxed);
251
252 return 0;
253 }
254
255 static int v4l2_buf_to_bufref(V4L2Buffer *in, int plane, AVBufferRef **buf)
256 {
257 int ret;
258
259 if (plane >= in->num_planes)
260 return AVERROR(EINVAL);
261
262 /* even though most encoders return 0 in data_offset encoding vp8 does require this value */
263 *buf = av_buffer_create((char *)in->plane_info[plane].mm_addr + in->planes[plane].data_offset,
264 in->plane_info[plane].length, v4l2_free_buffer, in, 0);
265 if (!*buf)
266 return AVERROR(ENOMEM);
267
268 ret = v4l2_buf_increase_ref(in);
269 if (ret)
270 av_buffer_unref(buf);
271
272 return ret;
273 }
274
275 static int v4l2_bufref_to_buf(V4L2Buffer *out, int plane, const uint8_t* data, int size, int offset)
276 {
277 unsigned int bytesused, length;
278
279 if (plane >= out->num_planes)
280 return AVERROR(EINVAL);
281
282 length = out->plane_info[plane].length;
283 bytesused = FFMIN(size+offset, length);
284
285 memcpy((uint8_t*)out->plane_info[plane].mm_addr+offset, data, FFMIN(size, length-offset));
286
287 if (V4L2_TYPE_IS_MULTIPLANAR(out->buf.type)) {
288 out->planes[plane].bytesused = bytesused;
289 out->planes[plane].length = length;
290 } else {
291 out->buf.bytesused = bytesused;
292 out->buf.length = length;
293 }
294
295 return 0;
296 }
297
298 static int v4l2_buffer_buf_to_swframe(AVFrame *frame, V4L2Buffer *avbuf)
299 {
300 int i, ret;
301
302 frame->format = avbuf->context->av_pix_fmt;
303
304 for (i = 0; i < avbuf->num_planes; i++) {
305 ret = v4l2_buf_to_bufref(avbuf, i, &frame->buf[i]);
306 if (ret)
307 return ret;
308
309 frame->linesize[i] = avbuf->plane_info[i].bytesperline;
310 frame->data[i] = frame->buf[i]->data;
311 }
312
313 /* fixup special cases */
314 switch (avbuf->context->av_pix_fmt) {
315 case AV_PIX_FMT_NV12:
316 case AV_PIX_FMT_NV21:
317 if (avbuf->num_planes > 1)
318 break;
319 frame->linesize[1] = avbuf->plane_info[0].bytesperline;
320 frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
321 break;
322
323 case AV_PIX_FMT_YUV420P:
324 if (avbuf->num_planes > 1)
325 break;
326 frame->linesize[1] = avbuf->plane_info[0].bytesperline >> 1;
327 frame->linesize[2] = avbuf->plane_info[0].bytesperline >> 1;
328 frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
329 frame->data[2] = frame->data[1] + ((avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height) >> 2);
330 break;
331
332 default:
333 break;
334 }
335
336 return 0;
337 }
338
339 static int v4l2_buffer_swframe_to_buf(const AVFrame *frame, V4L2Buffer *out)
340 {
341 int i, ret;
342 struct v4l2_format fmt = out->context->format;
343 int pixel_format = V4L2_TYPE_IS_MULTIPLANAR(fmt.type) ?
344 fmt.fmt.pix_mp.pixelformat : fmt.fmt.pix.pixelformat;
345 int height = V4L2_TYPE_IS_MULTIPLANAR(fmt.type) ?
346 fmt.fmt.pix_mp.height : fmt.fmt.pix.height;
347 int is_planar_format = 0;
348
349 switch (pixel_format) {
350 case V4L2_PIX_FMT_YUV420M:
351 case V4L2_PIX_FMT_YVU420M:
352 #ifdef V4L2_PIX_FMT_YUV422M
353 case V4L2_PIX_FMT_YUV422M:
354 #endif
355 #ifdef V4L2_PIX_FMT_YVU422M
356 case V4L2_PIX_FMT_YVU422M:
357 #endif
358 #ifdef V4L2_PIX_FMT_YUV444M
359 case V4L2_PIX_FMT_YUV444M:
360 #endif
361 #ifdef V4L2_PIX_FMT_YVU444M
362 case V4L2_PIX_FMT_YVU444M:
363 #endif
364 case V4L2_PIX_FMT_NV12M:
365 case V4L2_PIX_FMT_NV21M:
366 case V4L2_PIX_FMT_NV12MT_16X16:
367 case V4L2_PIX_FMT_NV12MT:
368 case V4L2_PIX_FMT_NV16M:
369 case V4L2_PIX_FMT_NV61M:
370 is_planar_format = 1;
371 }
372
373 if (!is_planar_format) {
374 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(frame->format);
375 int planes_nb = 0;
376 int offset = 0;
377
378 for (i = 0; i < desc->nb_components; i++)
379 planes_nb = FFMAX(planes_nb, desc->comp[i].plane + 1);
380
381 for (i = 0; i < planes_nb; i++) {
382 int size, h = height;
383 if (i == 1 || i == 2) {
384 h = AV_CEIL_RSHIFT(h, desc->log2_chroma_h);
385 }
386 size = frame->linesize[i] * h;
387 ret = v4l2_bufref_to_buf(out, 0, frame->data[i], size, offset);
388 if (ret)
389 return ret;
390 offset += size;
391 }
392 return 0;
393 }
394
395 for (i = 0; i < out->num_planes; i++) {
396 ret = v4l2_bufref_to_buf(out, i, frame->buf[i]->data, frame->buf[i]->size, 0);
397 if (ret)
398 return ret;
399 }
400
401 return 0;
402 }
403
404 /******************************************************************************
405 *
406 * V4L2Buffer interface
407 *
408 ******************************************************************************/
409
410 int ff_v4l2_buffer_avframe_to_buf(const AVFrame *frame, V4L2Buffer *out)
411 {
412 v4l2_set_pts(out, frame->pts);
413
414 return v4l2_buffer_swframe_to_buf(frame, out);
415 }
416
417 int ff_v4l2_buffer_buf_to_avframe(AVFrame *frame, V4L2Buffer *avbuf)
418 {
419 int ret;
420
421 av_frame_unref(frame);
422
423 /* 1. get references to the actual data */
424 ret = v4l2_buffer_buf_to_swframe(frame, avbuf);
425 if (ret)
426 return ret;
427
428 /* 2. get frame information */
429 if (avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME)
430 frame->flags |= AV_FRAME_FLAG_KEY;
431 frame->color_primaries = v4l2_get_color_primaries(avbuf);
432 frame->colorspace = v4l2_get_color_space(avbuf);
433 frame->color_range = v4l2_get_color_range(avbuf);
434 frame->color_trc = v4l2_get_color_trc(avbuf);
435 frame->pts = v4l2_get_pts(avbuf);
436 frame->pkt_dts = AV_NOPTS_VALUE;
437
438 /* these values are updated also during re-init in v4l2_process_driver_event */
439 frame->height = avbuf->context->height;
440 frame->width = avbuf->context->width;
441 frame->sample_aspect_ratio = avbuf->context->sample_aspect_ratio;
442
443 /* 3. report errors upstream */
444 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
445 av_log(logger(avbuf), AV_LOG_ERROR, "%s: driver decode error\n", avbuf->context->name);
446 frame->decode_error_flags |= FF_DECODE_ERROR_INVALID_BITSTREAM;
447 }
448
449 return 0;
450 }
451
452 int ff_v4l2_buffer_buf_to_avpkt(AVPacket *pkt, V4L2Buffer *avbuf)
453 {
454 int ret;
455
456 av_packet_unref(pkt);
457 ret = v4l2_buf_to_bufref(avbuf, 0, &pkt->buf);
458 if (ret)
459 return ret;
460
461 pkt->size = V4L2_TYPE_IS_MULTIPLANAR(avbuf->buf.type) ? avbuf->buf.m.planes[0].bytesused : avbuf->buf.bytesused;
462 pkt->data = pkt->buf->data;
463
464 if (avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME)
465 pkt->flags |= AV_PKT_FLAG_KEY;
466
467 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
468 av_log(logger(avbuf), AV_LOG_ERROR, "%s driver encode error\n", avbuf->context->name);
469 pkt->flags |= AV_PKT_FLAG_CORRUPT;
470 }
471
472 pkt->dts = pkt->pts = v4l2_get_pts(avbuf);
473
474 return 0;
475 }
476
477 int ff_v4l2_buffer_avpkt_to_buf(const AVPacket *pkt, V4L2Buffer *out)
478 {
479 int ret;
480
481 ret = v4l2_bufref_to_buf(out, 0, pkt->data, pkt->size, 0);
482 if (ret)
483 return ret;
484
485 v4l2_set_pts(out, pkt->pts);
486
487 if (pkt->flags & AV_PKT_FLAG_KEY)
488 out->flags = V4L2_BUF_FLAG_KEYFRAME;
489
490 return 0;
491 }
492
493 int ff_v4l2_buffer_initialize(V4L2Buffer* avbuf, int index)
494 {
495 V4L2Context *ctx = avbuf->context;
496 int ret, i;
497
498 avbuf->buf.memory = V4L2_MEMORY_MMAP;
499 avbuf->buf.type = ctx->type;
500 avbuf->buf.index = index;
501
502 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
503 avbuf->buf.length = VIDEO_MAX_PLANES;
504 avbuf->buf.m.planes = avbuf->planes;
505 }
506
507 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QUERYBUF, &avbuf->buf);
508 if (ret < 0)
509 return AVERROR(errno);
510
511 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
512 avbuf->num_planes = 0;
513 /* in MP, the V4L2 API states that buf.length means num_planes */
514 for (i = 0; i < avbuf->buf.length; i++) {
515 if (avbuf->buf.m.planes[i].length)
516 avbuf->num_planes++;
517 }
518 } else
519 avbuf->num_planes = 1;
520
521 for (i = 0; i < avbuf->num_planes; i++) {
522
523 avbuf->plane_info[i].bytesperline = V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ?
524 ctx->format.fmt.pix_mp.plane_fmt[i].bytesperline :
525 ctx->format.fmt.pix.bytesperline;
526
527 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
528 avbuf->plane_info[i].length = avbuf->buf.m.planes[i].length;
529 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.m.planes[i].length,
530 PROT_READ | PROT_WRITE, MAP_SHARED,
531 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.planes[i].m.mem_offset);
532 } else {
533 avbuf->plane_info[i].length = avbuf->buf.length;
534 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.length,
535 PROT_READ | PROT_WRITE, MAP_SHARED,
536 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.offset);
537 }
538
539 if (avbuf->plane_info[i].mm_addr == MAP_FAILED)
540 return AVERROR(ENOMEM);
541 }
542
543 avbuf->status = V4L2BUF_AVAILABLE;
544
545 if (V4L2_TYPE_IS_OUTPUT(ctx->type))
546 return 0;
547
548 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
549 avbuf->buf.m.planes = avbuf->planes;
550 avbuf->buf.length = avbuf->num_planes;
551
552 } else {
553 avbuf->buf.bytesused = avbuf->planes[0].bytesused;
554 avbuf->buf.length = avbuf->planes[0].length;
555 }
556
557 return ff_v4l2_buffer_enqueue(avbuf);
558 }
559
560 int ff_v4l2_buffer_enqueue(V4L2Buffer* avbuf)
561 {
562 int ret;
563
564 avbuf->buf.flags = avbuf->flags;
565
566 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QBUF, &avbuf->buf);
567 if (ret < 0)
568 return AVERROR(errno);
569
570 avbuf->status = V4L2BUF_IN_DRIVER;
571
572 return 0;
573 }
574