FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavcodec/v4l2_buffers.c
Date: 2025-10-10 03:51:19
Exec Total Coverage
Lines: 0 308 0.0%
Functions: 0 22 0.0%
Branches: 0 235 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 "libavutil/refstruct.h"
33 #include "v4l2_context.h"
34 #include "v4l2_buffers.h"
35 #include "v4l2_m2m.h"
36
37 #ifndef USEC_PER_SEC
38 #define USEC_PER_SEC 1000000
39 #endif
40
41 static AVRational v4l2_timebase = { 1, USEC_PER_SEC };
42
43 static inline V4L2m2mContext *buf_to_m2mctx(V4L2Buffer *buf)
44 {
45 return V4L2_TYPE_IS_OUTPUT(buf->context->type) ?
46 container_of(buf->context, V4L2m2mContext, output) :
47 container_of(buf->context, V4L2m2mContext, capture);
48 }
49
50 static inline AVCodecContext *logger(V4L2Buffer *buf)
51 {
52 return buf_to_m2mctx(buf)->avctx;
53 }
54
55 static inline AVRational v4l2_get_timebase(V4L2Buffer *avbuf)
56 {
57 V4L2m2mContext *s = buf_to_m2mctx(avbuf);
58
59 if (s->avctx->pkt_timebase.num)
60 return s->avctx->pkt_timebase;
61 return s->avctx->time_base;
62 }
63
64 static inline void v4l2_set_pts(V4L2Buffer *out, int64_t pts)
65 {
66 int64_t v4l2_pts;
67
68 if (pts == AV_NOPTS_VALUE)
69 pts = 0;
70
71 /* convert pts to v4l2 timebase */
72 v4l2_pts = av_rescale_q(pts, v4l2_get_timebase(out), v4l2_timebase);
73 out->buf.timestamp.tv_usec = v4l2_pts % USEC_PER_SEC;
74 out->buf.timestamp.tv_sec = v4l2_pts / USEC_PER_SEC;
75 }
76
77 static inline int64_t v4l2_get_pts(V4L2Buffer *avbuf)
78 {
79 int64_t v4l2_pts;
80
81 /* convert pts back to encoder timebase */
82 v4l2_pts = (int64_t)avbuf->buf.timestamp.tv_sec * USEC_PER_SEC +
83 avbuf->buf.timestamp.tv_usec;
84
85 return av_rescale_q(v4l2_pts, v4l2_timebase, v4l2_get_timebase(avbuf));
86 }
87
88 static enum AVColorPrimaries v4l2_get_color_primaries(V4L2Buffer *buf)
89 {
90 enum v4l2_ycbcr_encoding ycbcr;
91 enum v4l2_colorspace cs;
92
93 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
94 buf->context->format.fmt.pix_mp.colorspace :
95 buf->context->format.fmt.pix.colorspace;
96
97 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
98 buf->context->format.fmt.pix_mp.ycbcr_enc:
99 buf->context->format.fmt.pix.ycbcr_enc;
100
101 switch(ycbcr) {
102 case V4L2_YCBCR_ENC_XV709:
103 case V4L2_YCBCR_ENC_709: return AVCOL_PRI_BT709;
104 case V4L2_YCBCR_ENC_XV601:
105 case V4L2_YCBCR_ENC_601:return AVCOL_PRI_BT470M;
106 default:
107 break;
108 }
109
110 switch(cs) {
111 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_PRI_BT470BG;
112 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_PRI_SMPTE170M;
113 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_PRI_SMPTE240M;
114 case V4L2_COLORSPACE_BT2020: return AVCOL_PRI_BT2020;
115 default:
116 break;
117 }
118
119 return AVCOL_PRI_UNSPECIFIED;
120 }
121
122 static enum AVColorRange v4l2_get_color_range(V4L2Buffer *buf)
123 {
124 enum v4l2_quantization qt;
125
126 qt = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
127 buf->context->format.fmt.pix_mp.quantization :
128 buf->context->format.fmt.pix.quantization;
129
130 switch (qt) {
131 case V4L2_QUANTIZATION_LIM_RANGE: return AVCOL_RANGE_MPEG;
132 case V4L2_QUANTIZATION_FULL_RANGE: return AVCOL_RANGE_JPEG;
133 default:
134 break;
135 }
136
137 return AVCOL_RANGE_UNSPECIFIED;
138 }
139
140 static enum AVColorSpace v4l2_get_color_space(V4L2Buffer *buf)
141 {
142 enum v4l2_ycbcr_encoding ycbcr;
143 enum v4l2_colorspace cs;
144
145 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
146 buf->context->format.fmt.pix_mp.colorspace :
147 buf->context->format.fmt.pix.colorspace;
148
149 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
150 buf->context->format.fmt.pix_mp.ycbcr_enc:
151 buf->context->format.fmt.pix.ycbcr_enc;
152
153 switch(cs) {
154 case V4L2_COLORSPACE_SRGB: return AVCOL_SPC_RGB;
155 case V4L2_COLORSPACE_REC709: return AVCOL_SPC_BT709;
156 case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_SPC_FCC;
157 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_SPC_BT470BG;
158 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_SPC_SMPTE170M;
159 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_SPC_SMPTE240M;
160 case V4L2_COLORSPACE_BT2020:
161 if (ycbcr == V4L2_YCBCR_ENC_BT2020_CONST_LUM)
162 return AVCOL_SPC_BT2020_CL;
163 else
164 return AVCOL_SPC_BT2020_NCL;
165 default:
166 break;
167 }
168
169 return AVCOL_SPC_UNSPECIFIED;
170 }
171
172 static enum AVColorTransferCharacteristic v4l2_get_color_trc(V4L2Buffer *buf)
173 {
174 enum v4l2_ycbcr_encoding ycbcr;
175 enum v4l2_xfer_func xfer;
176 enum v4l2_colorspace cs;
177
178 cs = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
179 buf->context->format.fmt.pix_mp.colorspace :
180 buf->context->format.fmt.pix.colorspace;
181
182 ycbcr = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
183 buf->context->format.fmt.pix_mp.ycbcr_enc:
184 buf->context->format.fmt.pix.ycbcr_enc;
185
186 xfer = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
187 buf->context->format.fmt.pix_mp.xfer_func:
188 buf->context->format.fmt.pix.xfer_func;
189
190 switch (xfer) {
191 case V4L2_XFER_FUNC_709: return AVCOL_TRC_BT709;
192 case V4L2_XFER_FUNC_SRGB: return AVCOL_TRC_IEC61966_2_1;
193 default:
194 break;
195 }
196
197 switch (cs) {
198 case V4L2_COLORSPACE_470_SYSTEM_M: return AVCOL_TRC_GAMMA22;
199 case V4L2_COLORSPACE_470_SYSTEM_BG: return AVCOL_TRC_GAMMA28;
200 case V4L2_COLORSPACE_SMPTE170M: return AVCOL_TRC_SMPTE170M;
201 case V4L2_COLORSPACE_SMPTE240M: return AVCOL_TRC_SMPTE240M;
202 default:
203 break;
204 }
205
206 switch (ycbcr) {
207 case V4L2_YCBCR_ENC_XV709:
208 case V4L2_YCBCR_ENC_XV601: return AVCOL_TRC_BT1361_ECG;
209 default:
210 break;
211 }
212
213 return AVCOL_TRC_UNSPECIFIED;
214 }
215
216 static void v4l2_get_interlacing(AVFrame *frame, V4L2Buffer *buf)
217 {
218 enum v4l2_field field = V4L2_TYPE_IS_MULTIPLANAR(buf->buf.type) ?
219 buf->context->format.fmt.pix_mp.field :
220 buf->context->format.fmt.pix.field;
221
222 switch (field) {
223 case V4L2_FIELD_INTERLACED:
224 case V4L2_FIELD_INTERLACED_TB:
225 frame->flags |= AV_FRAME_FLAG_TOP_FIELD_FIRST;
226 /* fallthrough */
227 case V4L2_FIELD_INTERLACED_BT:
228 frame->flags |= AV_FRAME_FLAG_INTERLACED;
229 break;
230 }
231 }
232
233 static void v4l2_free_buffer(void *opaque, uint8_t *unused)
234 {
235 V4L2Buffer* avbuf = opaque;
236 V4L2m2mContext *s = buf_to_m2mctx(avbuf);
237
238 if (atomic_fetch_sub(&avbuf->context_refcount, 1) == 1) {
239 atomic_fetch_sub_explicit(&s->refcount, 1, memory_order_acq_rel);
240
241 if (s->reinit) {
242 if (!atomic_load(&s->refcount))
243 sem_post(&s->refsync);
244 } else {
245 if (s->draining && V4L2_TYPE_IS_OUTPUT(avbuf->context->type)) {
246 /* no need to queue more buffers to the driver */
247 avbuf->status = V4L2BUF_AVAILABLE;
248 }
249 else if (avbuf->context->streamon)
250 ff_v4l2_buffer_enqueue(avbuf);
251 }
252
253 av_refstruct_unref(&avbuf->context_ref);
254 }
255 }
256
257 static int v4l2_buf_increase_ref(V4L2Buffer *in)
258 {
259 V4L2m2mContext *s = buf_to_m2mctx(in);
260
261 if (in->context_ref)
262 atomic_fetch_add(&in->context_refcount, 1);
263 else {
264 in->context_ref = av_refstruct_ref(s->self_ref);
265
266 in->context_refcount = 1;
267 }
268
269 in->status = V4L2BUF_RET_USER;
270 atomic_fetch_add_explicit(&s->refcount, 1, memory_order_relaxed);
271
272 return 0;
273 }
274
275 static int v4l2_buf_to_bufref(V4L2Buffer *in, int plane, AVBufferRef **buf)
276 {
277 int ret;
278
279 if (plane >= in->num_planes)
280 return AVERROR(EINVAL);
281
282 /* even though most encoders return 0 in data_offset encoding vp8 does require this value */
283 *buf = av_buffer_create((char *)in->plane_info[plane].mm_addr + in->planes[plane].data_offset,
284 in->plane_info[plane].length, v4l2_free_buffer, in, 0);
285 if (!*buf)
286 return AVERROR(ENOMEM);
287
288 ret = v4l2_buf_increase_ref(in);
289 if (ret)
290 av_buffer_unref(buf);
291
292 return ret;
293 }
294
295 static int v4l2_bufref_to_buf(V4L2Buffer *out, int plane, const uint8_t* data, int size, int offset)
296 {
297 unsigned int bytesused, length;
298
299 if (plane >= out->num_planes)
300 return AVERROR(EINVAL);
301
302 length = out->plane_info[plane].length;
303 bytesused = FFMIN(size+offset, length);
304
305 memcpy((uint8_t*)out->plane_info[plane].mm_addr+offset, data, FFMIN(size, length-offset));
306
307 if (V4L2_TYPE_IS_MULTIPLANAR(out->buf.type)) {
308 out->planes[plane].bytesused = bytesused;
309 out->planes[plane].length = length;
310 } else {
311 out->buf.bytesused = bytesused;
312 out->buf.length = length;
313 }
314
315 return 0;
316 }
317
318 static int v4l2_buffer_buf_to_swframe(AVFrame *frame, V4L2Buffer *avbuf)
319 {
320 int i, ret;
321
322 frame->format = avbuf->context->av_pix_fmt;
323
324 for (i = 0; i < avbuf->num_planes; i++) {
325 ret = v4l2_buf_to_bufref(avbuf, i, &frame->buf[i]);
326 if (ret)
327 return ret;
328
329 frame->linesize[i] = avbuf->plane_info[i].bytesperline;
330 frame->data[i] = frame->buf[i]->data;
331 }
332
333 /* fixup special cases */
334 switch (avbuf->context->av_pix_fmt) {
335 case AV_PIX_FMT_NV12:
336 case AV_PIX_FMT_NV21:
337 if (avbuf->num_planes > 1)
338 break;
339 frame->linesize[1] = avbuf->plane_info[0].bytesperline;
340 frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
341 break;
342
343 case AV_PIX_FMT_YUV420P:
344 if (avbuf->num_planes > 1)
345 break;
346 frame->linesize[1] = avbuf->plane_info[0].bytesperline >> 1;
347 frame->linesize[2] = avbuf->plane_info[0].bytesperline >> 1;
348 frame->data[1] = frame->buf[0]->data + avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height;
349 frame->data[2] = frame->data[1] + ((avbuf->plane_info[0].bytesperline * avbuf->context->format.fmt.pix_mp.height) >> 2);
350 break;
351
352 default:
353 break;
354 }
355
356 return 0;
357 }
358
359 static int v4l2_buffer_swframe_to_buf(const AVFrame *frame, V4L2Buffer *out)
360 {
361 int i, ret;
362 struct v4l2_format fmt = out->context->format;
363 int pixel_format = V4L2_TYPE_IS_MULTIPLANAR(fmt.type) ?
364 fmt.fmt.pix_mp.pixelformat : fmt.fmt.pix.pixelformat;
365 int height = V4L2_TYPE_IS_MULTIPLANAR(fmt.type) ?
366 fmt.fmt.pix_mp.height : fmt.fmt.pix.height;
367 int is_planar_format = 0;
368
369 switch (pixel_format) {
370 case V4L2_PIX_FMT_YUV420M:
371 case V4L2_PIX_FMT_YVU420M:
372 #ifdef V4L2_PIX_FMT_YUV422M
373 case V4L2_PIX_FMT_YUV422M:
374 #endif
375 #ifdef V4L2_PIX_FMT_YVU422M
376 case V4L2_PIX_FMT_YVU422M:
377 #endif
378 #ifdef V4L2_PIX_FMT_YUV444M
379 case V4L2_PIX_FMT_YUV444M:
380 #endif
381 #ifdef V4L2_PIX_FMT_YVU444M
382 case V4L2_PIX_FMT_YVU444M:
383 #endif
384 case V4L2_PIX_FMT_NV12M:
385 case V4L2_PIX_FMT_NV21M:
386 case V4L2_PIX_FMT_NV12MT_16X16:
387 case V4L2_PIX_FMT_NV12MT:
388 case V4L2_PIX_FMT_NV16M:
389 case V4L2_PIX_FMT_NV61M:
390 is_planar_format = 1;
391 }
392
393 if (!is_planar_format) {
394 const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(frame->format);
395 int planes_nb = 0;
396 int offset = 0;
397
398 for (i = 0; i < desc->nb_components; i++)
399 planes_nb = FFMAX(planes_nb, desc->comp[i].plane + 1);
400
401 for (i = 0; i < planes_nb; i++) {
402 int size, h = height;
403 if (i == 1 || i == 2) {
404 h = AV_CEIL_RSHIFT(h, desc->log2_chroma_h);
405 }
406 size = frame->linesize[i] * h;
407 ret = v4l2_bufref_to_buf(out, 0, frame->data[i], size, offset);
408 if (ret)
409 return ret;
410 offset += size;
411 }
412 return 0;
413 }
414
415 for (i = 0; i < out->num_planes; i++) {
416 ret = v4l2_bufref_to_buf(out, i, frame->buf[i]->data, frame->buf[i]->size, 0);
417 if (ret)
418 return ret;
419 }
420
421 return 0;
422 }
423
424 /******************************************************************************
425 *
426 * V4L2Buffer interface
427 *
428 ******************************************************************************/
429
430 int ff_v4l2_buffer_avframe_to_buf(const AVFrame *frame, V4L2Buffer *out)
431 {
432 v4l2_set_pts(out, frame->pts);
433
434 return v4l2_buffer_swframe_to_buf(frame, out);
435 }
436
437 int ff_v4l2_buffer_buf_to_avframe(AVFrame *frame, V4L2Buffer *avbuf)
438 {
439 int ret;
440
441 av_frame_unref(frame);
442
443 /* 1. get references to the actual data */
444 ret = v4l2_buffer_buf_to_swframe(frame, avbuf);
445 if (ret)
446 return ret;
447
448 /* 2. get frame information */
449 if (avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME)
450 frame->flags |= AV_FRAME_FLAG_KEY;
451 frame->color_primaries = v4l2_get_color_primaries(avbuf);
452 frame->colorspace = v4l2_get_color_space(avbuf);
453 frame->color_range = v4l2_get_color_range(avbuf);
454 frame->color_trc = v4l2_get_color_trc(avbuf);
455 frame->pts = v4l2_get_pts(avbuf);
456 frame->pkt_dts = AV_NOPTS_VALUE;
457 v4l2_get_interlacing(frame, avbuf);
458
459 /* these values are updated also during re-init in v4l2_process_driver_event */
460 frame->height = avbuf->context->height;
461 frame->width = avbuf->context->width;
462 frame->sample_aspect_ratio = avbuf->context->sample_aspect_ratio;
463
464 /* 3. report errors upstream */
465 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
466 av_log(logger(avbuf), AV_LOG_ERROR, "%s: driver decode error\n", avbuf->context->name);
467 frame->decode_error_flags |= FF_DECODE_ERROR_INVALID_BITSTREAM;
468 }
469
470 return 0;
471 }
472
473 int ff_v4l2_buffer_buf_to_avpkt(AVPacket *pkt, V4L2Buffer *avbuf)
474 {
475 int ret;
476
477 av_packet_unref(pkt);
478 ret = v4l2_buf_to_bufref(avbuf, 0, &pkt->buf);
479 if (ret)
480 return ret;
481
482 pkt->size = V4L2_TYPE_IS_MULTIPLANAR(avbuf->buf.type) ? avbuf->buf.m.planes[0].bytesused : avbuf->buf.bytesused;
483 pkt->data = pkt->buf->data;
484
485 if (avbuf->buf.flags & V4L2_BUF_FLAG_KEYFRAME)
486 pkt->flags |= AV_PKT_FLAG_KEY;
487
488 if (avbuf->buf.flags & V4L2_BUF_FLAG_ERROR) {
489 av_log(logger(avbuf), AV_LOG_ERROR, "%s driver encode error\n", avbuf->context->name);
490 pkt->flags |= AV_PKT_FLAG_CORRUPT;
491 }
492
493 pkt->dts = pkt->pts = v4l2_get_pts(avbuf);
494
495 return 0;
496 }
497
498 int ff_v4l2_buffer_avpkt_to_buf(const AVPacket *pkt, V4L2Buffer *out)
499 {
500 int ret;
501
502 ret = v4l2_bufref_to_buf(out, 0, pkt->data, pkt->size, 0);
503 if (ret)
504 return ret;
505
506 v4l2_set_pts(out, pkt->pts);
507
508 if (pkt->flags & AV_PKT_FLAG_KEY)
509 out->flags = V4L2_BUF_FLAG_KEYFRAME;
510
511 return 0;
512 }
513
514 int ff_v4l2_buffer_initialize(V4L2Buffer* avbuf, int index)
515 {
516 V4L2Context *ctx = avbuf->context;
517 int ret, i;
518
519 avbuf->buf.memory = V4L2_MEMORY_MMAP;
520 avbuf->buf.type = ctx->type;
521 avbuf->buf.index = index;
522
523 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
524 avbuf->buf.length = VIDEO_MAX_PLANES;
525 avbuf->buf.m.planes = avbuf->planes;
526 }
527
528 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QUERYBUF, &avbuf->buf);
529 if (ret < 0)
530 return AVERROR(errno);
531
532 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
533 avbuf->num_planes = 0;
534 /* in MP, the V4L2 API states that buf.length means num_planes */
535 for (i = 0; i < avbuf->buf.length; i++) {
536 if (avbuf->buf.m.planes[i].length)
537 avbuf->num_planes++;
538 }
539 } else
540 avbuf->num_planes = 1;
541
542 for (i = 0; i < avbuf->num_planes; i++) {
543
544 avbuf->plane_info[i].bytesperline = V4L2_TYPE_IS_MULTIPLANAR(ctx->type) ?
545 ctx->format.fmt.pix_mp.plane_fmt[i].bytesperline :
546 ctx->format.fmt.pix.bytesperline;
547
548 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
549 avbuf->plane_info[i].length = avbuf->buf.m.planes[i].length;
550 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.m.planes[i].length,
551 PROT_READ | PROT_WRITE, MAP_SHARED,
552 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.planes[i].m.mem_offset);
553 } else {
554 avbuf->plane_info[i].length = avbuf->buf.length;
555 avbuf->plane_info[i].mm_addr = mmap(NULL, avbuf->buf.length,
556 PROT_READ | PROT_WRITE, MAP_SHARED,
557 buf_to_m2mctx(avbuf)->fd, avbuf->buf.m.offset);
558 }
559
560 if (avbuf->plane_info[i].mm_addr == MAP_FAILED)
561 return AVERROR(ENOMEM);
562 }
563
564 avbuf->status = V4L2BUF_AVAILABLE;
565
566 if (V4L2_TYPE_IS_OUTPUT(ctx->type))
567 return 0;
568
569 if (V4L2_TYPE_IS_MULTIPLANAR(ctx->type)) {
570 avbuf->buf.m.planes = avbuf->planes;
571 avbuf->buf.length = avbuf->num_planes;
572
573 } else {
574 avbuf->buf.bytesused = avbuf->planes[0].bytesused;
575 avbuf->buf.length = avbuf->planes[0].length;
576 }
577
578 return ff_v4l2_buffer_enqueue(avbuf);
579 }
580
581 int ff_v4l2_buffer_enqueue(V4L2Buffer* avbuf)
582 {
583 int ret;
584
585 avbuf->buf.flags = avbuf->flags;
586
587 ret = ioctl(buf_to_m2mctx(avbuf)->fd, VIDIOC_QBUF, &avbuf->buf);
588 if (ret < 0)
589 return AVERROR(errno);
590
591 avbuf->status = V4L2BUF_IN_DRIVER;
592
593 return 0;
594 }
595