1/* 2 * Copyright (c) 2000,2001 Fabrice Bellard 3 * Copyright (c) 2006 Luca Abeni 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22/** 23 * @file 24 * Video4Linux2 grab interface 25 * 26 * Part of this file is based on the V4L2 video capture example 27 * (http://linuxtv.org/downloads/v4l-dvb-apis/capture-example.html) 28 * 29 * Thanks to Michael Niedermayer for providing the mapping between 30 * V4L2_PIX_FMT_* and AV_PIX_FMT_* 31 */ 32 33#include "v4l2-common.h" 34 35#if CONFIG_LIBV4L2 36#include <libv4l2.h> 37#endif 38 39static const int desired_video_buffers = 256; 40 41#define V4L_ALLFORMATS 3 42#define V4L_RAWFORMATS 1 43#define V4L_COMPFORMATS 2 44 45/** 46 * Return timestamps to the user exactly as returned by the kernel 47 */ 48#define V4L_TS_DEFAULT 0 49/** 50 * Autodetect the kind of timestamps returned by the kernel and convert to 51 * absolute (wall clock) timestamps. 52 */ 53#define V4L_TS_ABS 1 54/** 55 * Assume kernel timestamps are from the monotonic clock and convert to 56 * absolute timestamps. 57 */ 58#define V4L_TS_MONO2ABS 2 59 60/** 61 * Once the kind of timestamps returned by the kernel have been detected, 62 * the value of the timefilter (NULL or not) determines whether a conversion 63 * takes place. 64 */ 65#define V4L_TS_CONVERT_READY V4L_TS_DEFAULT 66 67struct video_data { 68 AVClass *class; 69 int fd; 70 int frame_format; /* V4L2_PIX_FMT_* */ 71 int width, height; 72 int frame_size; 73 int interlaced; 74 int top_field_first; 75 int ts_mode; 76 TimeFilter *timefilter; 77 int64_t last_time_m; 78 79 int buffers; 80 volatile int buffers_queued; 81 void **buf_start; 82 unsigned int *buf_len; 83 char *standard; 84 v4l2_std_id std_id; 85 int channel; 86 char *pixel_format; /**< Set by a private option. */ 87 int list_format; /**< Set by a private option. */ 88 int list_standard; /**< Set by a private option. */ 89 char *framerate; /**< Set by a private option. */ 90 91 int use_libv4l2; 92 int (*open_f)(const char *file, int oflag, ...); 93 int (*close_f)(int fd); 94 int (*dup_f)(int fd); 95 int (*ioctl_f)(int fd, unsigned long int request, ...); 96 ssize_t (*read_f)(int fd, void *buffer, size_t n); 97 void *(*mmap_f)(void *start, size_t length, int prot, int flags, int fd, int64_t offset); 98 int (*munmap_f)(void *_start, size_t length); 99}; 100 101struct buff_data { 102 struct video_data *s; 103 int index; 104}; 105 106static int device_open(AVFormatContext *ctx) 107{ 108 struct video_data *s = ctx->priv_data; 109 struct v4l2_capability cap; 110 int fd; 111 int ret; 112 int flags = O_RDWR; 113 114#define SET_WRAPPERS(prefix) do { \ 115 s->open_f = prefix ## open; \ 116 s->close_f = prefix ## close; \ 117 s->dup_f = prefix ## dup; \ 118 s->ioctl_f = prefix ## ioctl; \ 119 s->read_f = prefix ## read; \ 120 s->mmap_f = prefix ## mmap; \ 121 s->munmap_f = prefix ## munmap; \ 122} while (0) 123 124 if (s->use_libv4l2) { 125#if CONFIG_LIBV4L2 126 SET_WRAPPERS(v4l2_); 127#else 128 av_log(ctx, AV_LOG_ERROR, "libavdevice is not build with libv4l2 support.\n"); 129 return AVERROR(EINVAL); 130#endif 131 } else { 132 SET_WRAPPERS(); 133 } 134 135#define v4l2_open s->open_f 136#define v4l2_close s->close_f 137#define v4l2_dup s->dup_f 138#define v4l2_ioctl s->ioctl_f 139#define v4l2_read s->read_f 140#define v4l2_mmap s->mmap_f 141#define v4l2_munmap s->munmap_f 142 143 if (ctx->flags & AVFMT_FLAG_NONBLOCK) { 144 flags |= O_NONBLOCK; 145 } 146 147 fd = v4l2_open(ctx->filename, flags, 0); 148 if (fd < 0) { 149 ret = AVERROR(errno); 150 av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s: %s\n", 151 ctx->filename, av_err2str(ret)); 152 return ret; 153 } 154 155 if (v4l2_ioctl(fd, VIDIOC_QUERYCAP, &cap) < 0) { 156 ret = AVERROR(errno); 157 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n", 158 av_err2str(ret)); 159 goto fail; 160 } 161 162 av_log(ctx, AV_LOG_VERBOSE, "fd:%d capabilities:%x\n", 163 fd, cap.capabilities); 164 165 if (!(cap.capabilities & V4L2_CAP_VIDEO_CAPTURE)) { 166 av_log(ctx, AV_LOG_ERROR, "Not a video capture device.\n"); 167 ret = AVERROR(ENODEV); 168 goto fail; 169 } 170 171 if (!(cap.capabilities & V4L2_CAP_STREAMING)) { 172 av_log(ctx, AV_LOG_ERROR, 173 "The device does not support the streaming I/O method.\n"); 174 ret = AVERROR(ENOSYS); 175 goto fail; 176 } 177 178 return fd; 179 180fail: 181 v4l2_close(fd); 182 return ret; 183} 184 185static int device_init(AVFormatContext *ctx, int *width, int *height, 186 uint32_t pix_fmt) 187{ 188 struct video_data *s = ctx->priv_data; 189 int fd = s->fd; 190 struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE }; 191 struct v4l2_pix_format *pix = &fmt.fmt.pix; 192 193 int res = 0; 194 195 pix->width = *width; 196 pix->height = *height; 197 pix->pixelformat = pix_fmt; 198 pix->field = V4L2_FIELD_ANY; 199 200 if (v4l2_ioctl(fd, VIDIOC_S_FMT, &fmt) < 0) 201 res = AVERROR(errno); 202 203 if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) { 204 av_log(ctx, AV_LOG_INFO, 205 "The V4L2 driver changed the video from %dx%d to %dx%d\n", 206 *width, *height, fmt.fmt.pix.width, fmt.fmt.pix.height); 207 *width = fmt.fmt.pix.width; 208 *height = fmt.fmt.pix.height; 209 } 210 211 if (pix_fmt != fmt.fmt.pix.pixelformat) { 212 av_log(ctx, AV_LOG_DEBUG, 213 "The V4L2 driver changed the pixel format " 214 "from 0x%08X to 0x%08X\n", 215 pix_fmt, fmt.fmt.pix.pixelformat); 216 res = AVERROR(EINVAL); 217 } 218 219 if (fmt.fmt.pix.field == V4L2_FIELD_INTERLACED) { 220 av_log(ctx, AV_LOG_DEBUG, 221 "The V4L2 driver is using the interlaced mode\n"); 222 s->interlaced = 1; 223 } 224 225 return res; 226} 227 228static int first_field(const struct video_data *s, int fd) 229{ 230 int res; 231 v4l2_std_id std; 232 233 res = v4l2_ioctl(fd, VIDIOC_G_STD, &std); 234 if (res < 0) { 235 return 0; 236 } 237 if (std & V4L2_STD_NTSC) { 238 return 0; 239 } 240 241 return 1; 242} 243 244#if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE 245static void list_framesizes(AVFormatContext *ctx, int fd, uint32_t pixelformat) 246{ 247 const struct video_data *s = ctx->priv_data; 248 struct v4l2_frmsizeenum vfse = { .pixel_format = pixelformat }; 249 250 while(!v4l2_ioctl(fd, VIDIOC_ENUM_FRAMESIZES, &vfse)) { 251 switch (vfse.type) { 252 case V4L2_FRMSIZE_TYPE_DISCRETE: 253 av_log(ctx, AV_LOG_INFO, " %ux%u", 254 vfse.discrete.width, vfse.discrete.height); 255 break; 256 case V4L2_FRMSIZE_TYPE_CONTINUOUS: 257 case V4L2_FRMSIZE_TYPE_STEPWISE: 258 av_log(ctx, AV_LOG_INFO, " {%u-%u, %u}x{%u-%u, %u}", 259 vfse.stepwise.min_width, 260 vfse.stepwise.max_width, 261 vfse.stepwise.step_width, 262 vfse.stepwise.min_height, 263 vfse.stepwise.max_height, 264 vfse.stepwise.step_height); 265 } 266 vfse.index++; 267 } 268} 269#endif 270 271static void list_formats(AVFormatContext *ctx, int fd, int type) 272{ 273 const struct video_data *s = ctx->priv_data; 274 struct v4l2_fmtdesc vfd = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE }; 275 276 while(!v4l2_ioctl(fd, VIDIOC_ENUM_FMT, &vfd)) { 277 enum AVCodecID codec_id = avpriv_fmt_v4l2codec(vfd.pixelformat); 278 enum AVPixelFormat pix_fmt = avpriv_fmt_v4l2ff(vfd.pixelformat, codec_id); 279 280 vfd.index++; 281 282 if (!(vfd.flags & V4L2_FMT_FLAG_COMPRESSED) && 283 type & V4L_RAWFORMATS) { 284 const char *fmt_name = av_get_pix_fmt_name(pix_fmt); 285 av_log(ctx, AV_LOG_INFO, "Raw : %9s : %20s :", 286 fmt_name ? fmt_name : "Unsupported", 287 vfd.description); 288 } else if (vfd.flags & V4L2_FMT_FLAG_COMPRESSED && 289 type & V4L_COMPFORMATS) { 290 AVCodec *codec = avcodec_find_decoder(codec_id); 291 av_log(ctx, AV_LOG_INFO, "Compressed: %9s : %20s :", 292 codec ? codec->name : "Unsupported", 293 vfd.description); 294 } else { 295 continue; 296 } 297 298#ifdef V4L2_FMT_FLAG_EMULATED 299 if (vfd.flags & V4L2_FMT_FLAG_EMULATED) 300 av_log(ctx, AV_LOG_INFO, " Emulated :"); 301#endif 302#if HAVE_STRUCT_V4L2_FRMIVALENUM_DISCRETE 303 list_framesizes(ctx, fd, vfd.pixelformat); 304#endif 305 av_log(ctx, AV_LOG_INFO, "\n"); 306 } 307} 308 309static void list_standards(AVFormatContext *ctx) 310{ 311 int ret; 312 struct video_data *s = ctx->priv_data; 313 struct v4l2_standard standard; 314 315 if (s->std_id == 0) 316 return; 317 318 for (standard.index = 0; ; standard.index++) { 319 if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) { 320 ret = AVERROR(errno); 321 if (ret == AVERROR(EINVAL)) { 322 break; 323 } else { 324 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret)); 325 return; 326 } 327 } 328 av_log(ctx, AV_LOG_INFO, "%2d, %16"PRIx64", %s\n", 329 standard.index, (uint64_t)standard.id, standard.name); 330 } 331} 332 333static int mmap_init(AVFormatContext *ctx) 334{ 335 int i, res; 336 struct video_data *s = ctx->priv_data; 337 struct v4l2_requestbuffers req = { 338 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE, 339 .count = desired_video_buffers, 340 .memory = V4L2_MEMORY_MMAP 341 }; 342 343 if (v4l2_ioctl(s->fd, VIDIOC_REQBUFS, &req) < 0) { 344 res = AVERROR(errno); 345 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS): %s\n", av_err2str(res)); 346 return res; 347 } 348 349 if (req.count < 2) { 350 av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n"); 351 return AVERROR(ENOMEM); 352 } 353 s->buffers = req.count; 354 s->buf_start = av_malloc_array(s->buffers, sizeof(void *)); 355 if (s->buf_start == NULL) { 356 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n"); 357 return AVERROR(ENOMEM); 358 } 359 s->buf_len = av_malloc_array(s->buffers, sizeof(unsigned int)); 360 if (s->buf_len == NULL) { 361 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n"); 362 av_free(s->buf_start); 363 return AVERROR(ENOMEM); 364 } 365 366 for (i = 0; i < req.count; i++) { 367 struct v4l2_buffer buf = { 368 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE, 369 .index = i, 370 .memory = V4L2_MEMORY_MMAP 371 }; 372 if (v4l2_ioctl(s->fd, VIDIOC_QUERYBUF, &buf) < 0) { 373 res = AVERROR(errno); 374 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF): %s\n", av_err2str(res)); 375 return res; 376 } 377 378 s->buf_len[i] = buf.length; 379 if (s->frame_size > 0 && s->buf_len[i] < s->frame_size) { 380 av_log(ctx, AV_LOG_ERROR, 381 "buf_len[%d] = %d < expected frame size %d\n", 382 i, s->buf_len[i], s->frame_size); 383 return AVERROR(ENOMEM); 384 } 385 s->buf_start[i] = v4l2_mmap(NULL, buf.length, 386 PROT_READ | PROT_WRITE, MAP_SHARED, 387 s->fd, buf.m.offset); 388 389 if (s->buf_start[i] == MAP_FAILED) { 390 res = AVERROR(errno); 391 av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", av_err2str(res)); 392 return res; 393 } 394 } 395 396 return 0; 397} 398 399#if FF_API_DESTRUCT_PACKET 400static void dummy_release_buffer(AVPacket *pkt) 401{ 402 av_assert0(0); 403} 404#endif 405 406static void mmap_release_buffer(void *opaque, uint8_t *data) 407{ 408 struct v4l2_buffer buf = { 0 }; 409 int res; 410 struct buff_data *buf_descriptor = opaque; 411 struct video_data *s = buf_descriptor->s; 412 413 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; 414 buf.memory = V4L2_MEMORY_MMAP; 415 buf.index = buf_descriptor->index; 416 av_free(buf_descriptor); 417 418 if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) < 0) { 419 res = AVERROR(errno); 420 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", 421 av_err2str(res)); 422 } 423 424 avpriv_atomic_int_add_and_fetch(&s->buffers_queued, 1); 425} 426 427#if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC) 428static int64_t av_gettime_monotonic(void) 429{ 430 return av_gettime_relative(); 431} 432#endif 433 434static int init_convert_timestamp(AVFormatContext *ctx, int64_t ts) 435{ 436 struct video_data *s = ctx->priv_data; 437 int64_t now; 438 439 now = av_gettime(); 440 if (s->ts_mode == V4L_TS_ABS && 441 ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE) { 442 av_log(ctx, AV_LOG_INFO, "Detected absolute timestamps\n"); 443 s->ts_mode = V4L_TS_CONVERT_READY; 444 return 0; 445 } 446#if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC) 447 if (ctx->streams[0]->avg_frame_rate.num) { 448 now = av_gettime_monotonic(); 449 if (s->ts_mode == V4L_TS_MONO2ABS || 450 (ts <= now + 1 * AV_TIME_BASE && ts >= now - 10 * AV_TIME_BASE)) { 451 AVRational tb = {AV_TIME_BASE, 1}; 452 int64_t period = av_rescale_q(1, tb, ctx->streams[0]->avg_frame_rate); 453 av_log(ctx, AV_LOG_INFO, "Detected monotonic timestamps, converting\n"); 454 /* microseconds instead of seconds, MHz instead of Hz */ 455 s->timefilter = ff_timefilter_new(1, period, 1.0E-6); 456 if (!s->timefilter) 457 return AVERROR(ENOMEM); 458 s->ts_mode = V4L_TS_CONVERT_READY; 459 return 0; 460 } 461 } 462#endif 463 av_log(ctx, AV_LOG_ERROR, "Unknown timestamps\n"); 464 return AVERROR(EIO); 465} 466 467static int convert_timestamp(AVFormatContext *ctx, int64_t *ts) 468{ 469 struct video_data *s = ctx->priv_data; 470 471 if (s->ts_mode) { 472 int r = init_convert_timestamp(ctx, *ts); 473 if (r < 0) 474 return r; 475 } 476#if HAVE_CLOCK_GETTIME && defined(CLOCK_MONOTONIC) 477 if (s->timefilter) { 478 int64_t nowa = av_gettime(); 479 int64_t nowm = av_gettime_monotonic(); 480 ff_timefilter_update(s->timefilter, nowa, nowm - s->last_time_m); 481 s->last_time_m = nowm; 482 *ts = ff_timefilter_eval(s->timefilter, *ts - nowm); 483 } 484#endif 485 return 0; 486} 487 488static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt) 489{ 490 struct video_data *s = ctx->priv_data; 491 struct v4l2_buffer buf = { 492 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE, 493 .memory = V4L2_MEMORY_MMAP 494 }; 495 int res; 496 497 /* FIXME: Some special treatment might be needed in case of loss of signal... */ 498 while ((res = v4l2_ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR)); 499 if (res < 0) { 500 if (errno == EAGAIN) { 501 pkt->size = 0; 502 return AVERROR(EAGAIN); 503 } 504 res = AVERROR(errno); 505 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n", av_err2str(res)); 506 return res; 507 } 508 509 if (buf.index >= s->buffers) { 510 av_log(ctx, AV_LOG_ERROR, "Invalid buffer index received.\n"); 511 return AVERROR(EINVAL); 512 } 513 avpriv_atomic_int_add_and_fetch(&s->buffers_queued, -1); 514 // always keep at least one buffer queued 515 av_assert0(avpriv_atomic_int_get(&s->buffers_queued) >= 1); 516 517 /* CPIA is a compressed format and we don't know the exact number of bytes 518 * used by a frame, so set it here as the driver announces it. 519 */ 520 if (ctx->video_codec_id == AV_CODEC_ID_CPIA) 521 s->frame_size = buf.bytesused; 522 523 if (s->frame_size > 0 && buf.bytesused != s->frame_size) { 524 av_log(ctx, AV_LOG_ERROR, 525 "The v4l2 frame is %d bytes, but %d bytes are expected\n", 526 buf.bytesused, s->frame_size); 527 return AVERROR_INVALIDDATA; 528 } 529 530 /* Image is at s->buff_start[buf.index] */ 531 if (avpriv_atomic_int_get(&s->buffers_queued) == FFMAX(s->buffers / 8, 1)) { 532 /* when we start getting low on queued buffers, fall back on copying data */ 533 res = av_new_packet(pkt, buf.bytesused); 534 if (res < 0) { 535 av_log(ctx, AV_LOG_ERROR, "Error allocating a packet.\n"); 536 if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) == 0) 537 avpriv_atomic_int_add_and_fetch(&s->buffers_queued, 1); 538 return res; 539 } 540 memcpy(pkt->data, s->buf_start[buf.index], buf.bytesused); 541 542 if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) < 0) { 543 res = AVERROR(errno); 544 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", av_err2str(res)); 545 av_free_packet(pkt); 546 return res; 547 } 548 avpriv_atomic_int_add_and_fetch(&s->buffers_queued, 1); 549 } else { 550 struct buff_data *buf_descriptor; 551 552 pkt->data = s->buf_start[buf.index]; 553 pkt->size = buf.bytesused; 554#if FF_API_DESTRUCT_PACKET 555FF_DISABLE_DEPRECATION_WARNINGS 556 pkt->destruct = dummy_release_buffer; 557FF_ENABLE_DEPRECATION_WARNINGS 558#endif 559 560 buf_descriptor = av_malloc(sizeof(struct buff_data)); 561 if (buf_descriptor == NULL) { 562 /* Something went wrong... Since av_malloc() failed, we cannot even 563 * allocate a buffer for memcpying into it 564 */ 565 av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n"); 566 if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) == 0) 567 avpriv_atomic_int_add_and_fetch(&s->buffers_queued, 1); 568 569 return AVERROR(ENOMEM); 570 } 571 buf_descriptor->index = buf.index; 572 buf_descriptor->s = s; 573 574 pkt->buf = av_buffer_create(pkt->data, pkt->size, mmap_release_buffer, 575 buf_descriptor, 0); 576 if (!pkt->buf) { 577 av_log(ctx, AV_LOG_ERROR, "Failed to create a buffer\n"); 578 if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) == 0) 579 avpriv_atomic_int_add_and_fetch(&s->buffers_queued, 1); 580 av_freep(&buf_descriptor); 581 return AVERROR(ENOMEM); 582 } 583 } 584 pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec; 585 convert_timestamp(ctx, &pkt->pts); 586 587 return s->buf_len[buf.index]; 588} 589 590static int mmap_start(AVFormatContext *ctx) 591{ 592 struct video_data *s = ctx->priv_data; 593 enum v4l2_buf_type type; 594 int i, res; 595 596 for (i = 0; i < s->buffers; i++) { 597 struct v4l2_buffer buf = { 598 .type = V4L2_BUF_TYPE_VIDEO_CAPTURE, 599 .index = i, 600 .memory = V4L2_MEMORY_MMAP 601 }; 602 603 if (v4l2_ioctl(s->fd, VIDIOC_QBUF, &buf) < 0) { 604 res = AVERROR(errno); 605 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", av_err2str(res)); 606 return res; 607 } 608 } 609 s->buffers_queued = s->buffers; 610 611 type = V4L2_BUF_TYPE_VIDEO_CAPTURE; 612 if (v4l2_ioctl(s->fd, VIDIOC_STREAMON, &type) < 0) { 613 res = AVERROR(errno); 614 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n", av_err2str(res)); 615 return res; 616 } 617 618 return 0; 619} 620 621static void mmap_close(struct video_data *s) 622{ 623 enum v4l2_buf_type type; 624 int i; 625 626 type = V4L2_BUF_TYPE_VIDEO_CAPTURE; 627 /* We do not check for the result, because we could 628 * not do anything about it anyway... 629 */ 630 v4l2_ioctl(s->fd, VIDIOC_STREAMOFF, &type); 631 for (i = 0; i < s->buffers; i++) { 632 v4l2_munmap(s->buf_start[i], s->buf_len[i]); 633 } 634 av_free(s->buf_start); 635 av_free(s->buf_len); 636} 637 638static int v4l2_set_parameters(AVFormatContext *s1) 639{ 640 struct video_data *s = s1->priv_data; 641 struct v4l2_standard standard = { 0 }; 642 struct v4l2_streamparm streamparm = { 0 }; 643 struct v4l2_fract *tpf; 644 AVRational framerate_q = { 0 }; 645 int i, ret; 646 647 if (s->framerate && 648 (ret = av_parse_video_rate(&framerate_q, s->framerate)) < 0) { 649 av_log(s1, AV_LOG_ERROR, "Could not parse framerate '%s'.\n", 650 s->framerate); 651 return ret; 652 } 653 654 if (s->standard) { 655 if (s->std_id) { 656 ret = 0; 657 av_log(s1, AV_LOG_DEBUG, "Setting standard: %s\n", s->standard); 658 /* set tv standard */ 659 for (i = 0; ; i++) { 660 standard.index = i; 661 if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) { 662 ret = AVERROR(errno); 663 break; 664 } 665 if (!av_strcasecmp(standard.name, s->standard)) 666 break; 667 } 668 if (ret < 0) { 669 av_log(s1, AV_LOG_ERROR, "Unknown or unsupported standard '%s'\n", s->standard); 670 return ret; 671 } 672 673 if (v4l2_ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) { 674 ret = AVERROR(errno); 675 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_S_STD): %s\n", av_err2str(ret)); 676 return ret; 677 } 678 } else { 679 av_log(s1, AV_LOG_WARNING, 680 "This device does not support any standard\n"); 681 } 682 } 683 684 /* get standard */ 685 if (v4l2_ioctl(s->fd, VIDIOC_G_STD, &s->std_id) == 0) { 686 tpf = &standard.frameperiod; 687 for (i = 0; ; i++) { 688 standard.index = i; 689 if (v4l2_ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) { 690 ret = AVERROR(errno); 691 if (ret == AVERROR(EINVAL)) { 692 tpf = &streamparm.parm.capture.timeperframe; 693 break; 694 } 695 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMSTD): %s\n", av_err2str(ret)); 696 return ret; 697 } 698 if (standard.id == s->std_id) { 699 av_log(s1, AV_LOG_DEBUG, 700 "Current standard: %s, id: %"PRIx64", frameperiod: %d/%d\n", 701 standard.name, (uint64_t)standard.id, tpf->numerator, tpf->denominator); 702 break; 703 } 704 } 705 } else { 706 tpf = &streamparm.parm.capture.timeperframe; 707 } 708 709 streamparm.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; 710 if (v4l2_ioctl(s->fd, VIDIOC_G_PARM, &streamparm) < 0) { 711 ret = AVERROR(errno); 712 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_PARM): %s\n", av_err2str(ret)); 713 return ret; 714 } 715 716 if (framerate_q.num && framerate_q.den) { 717 if (streamparm.parm.capture.capability & V4L2_CAP_TIMEPERFRAME) { 718 tpf = &streamparm.parm.capture.timeperframe; 719 720 av_log(s1, AV_LOG_DEBUG, "Setting time per frame to %d/%d\n", 721 framerate_q.den, framerate_q.num); 722 tpf->numerator = framerate_q.den; 723 tpf->denominator = framerate_q.num; 724 725 if (v4l2_ioctl(s->fd, VIDIOC_S_PARM, &streamparm) < 0) { 726 ret = AVERROR(errno); 727 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_S_PARM): %s\n", av_err2str(ret)); 728 return ret; 729 } 730 731 if (framerate_q.num != tpf->denominator || 732 framerate_q.den != tpf->numerator) { 733 av_log(s1, AV_LOG_INFO, 734 "The driver changed the time per frame from " 735 "%d/%d to %d/%d\n", 736 framerate_q.den, framerate_q.num, 737 tpf->numerator, tpf->denominator); 738 } 739 } else { 740 av_log(s1, AV_LOG_WARNING, 741 "The driver does not allow to change time per frame\n"); 742 } 743 } 744 if (tpf->denominator > 0 && tpf->numerator > 0) { 745 s1->streams[0]->avg_frame_rate.num = tpf->denominator; 746 s1->streams[0]->avg_frame_rate.den = tpf->numerator; 747 s1->streams[0]->r_frame_rate = s1->streams[0]->avg_frame_rate; 748 } else 749 av_log(s1, AV_LOG_WARNING, "Time per frame unknown\n"); 750 751 return 0; 752} 753 754static int device_try_init(AVFormatContext *s1, 755 enum AVPixelFormat pix_fmt, 756 int *width, 757 int *height, 758 uint32_t *desired_format, 759 enum AVCodecID *codec_id) 760{ 761 int ret, i; 762 763 *desired_format = avpriv_fmt_ff2v4l(pix_fmt, s1->video_codec_id); 764 765 if (*desired_format) { 766 ret = device_init(s1, width, height, *desired_format); 767 if (ret < 0) { 768 *desired_format = 0; 769 if (ret != AVERROR(EINVAL)) 770 return ret; 771 } 772 } 773 774 if (!*desired_format) { 775 for (i = 0; avpriv_fmt_conversion_table[i].codec_id != AV_CODEC_ID_NONE; i++) { 776 if (s1->video_codec_id == AV_CODEC_ID_NONE || 777 avpriv_fmt_conversion_table[i].codec_id == s1->video_codec_id) { 778 av_log(s1, AV_LOG_DEBUG, "Trying to set codec:%s pix_fmt:%s\n", 779 avcodec_get_name(avpriv_fmt_conversion_table[i].codec_id), 780 (char *)av_x_if_null(av_get_pix_fmt_name(avpriv_fmt_conversion_table[i].ff_fmt), "none")); 781 782 *desired_format = avpriv_fmt_conversion_table[i].v4l2_fmt; 783 ret = device_init(s1, width, height, *desired_format); 784 if (ret >= 0) 785 break; 786 else if (ret != AVERROR(EINVAL)) 787 return ret; 788 *desired_format = 0; 789 } 790 } 791 792 if (*desired_format == 0) { 793 av_log(s1, AV_LOG_ERROR, "Cannot find a proper format for " 794 "codec '%s' (id %d), pixel format '%s' (id %d)\n", 795 avcodec_get_name(s1->video_codec_id), s1->video_codec_id, 796 (char *)av_x_if_null(av_get_pix_fmt_name(pix_fmt), "none"), pix_fmt); 797 ret = AVERROR(EINVAL); 798 } 799 } 800 801 *codec_id = avpriv_fmt_v4l2codec(*desired_format); 802 av_assert0(*codec_id != AV_CODEC_ID_NONE); 803 return ret; 804} 805 806static int v4l2_read_header(AVFormatContext *s1) 807{ 808 struct video_data *s = s1->priv_data; 809 AVStream *st; 810 int res = 0; 811 uint32_t desired_format; 812 enum AVCodecID codec_id = AV_CODEC_ID_NONE; 813 enum AVPixelFormat pix_fmt = AV_PIX_FMT_NONE; 814 struct v4l2_input input = { 0 }; 815 816 st = avformat_new_stream(s1, NULL); 817 if (!st) 818 return AVERROR(ENOMEM); 819 820#if CONFIG_LIBV4L2 821 /* silence libv4l2 logging. if fopen() fails v4l2_log_file will be NULL 822 and errors will get sent to stderr */ 823 if (s->use_libv4l2) 824 v4l2_log_file = fopen("/dev/null", "w"); 825#endif 826 827 s->fd = device_open(s1); 828 if (s->fd < 0) 829 return s->fd; 830 831 if (s->channel != -1) { 832 /* set video input */ 833 av_log(s1, AV_LOG_DEBUG, "Selecting input_channel: %d\n", s->channel); 834 if (v4l2_ioctl(s->fd, VIDIOC_S_INPUT, &s->channel) < 0) { 835 res = AVERROR(errno); 836 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_S_INPUT): %s\n", av_err2str(res)); 837 return res; 838 } 839 } else { 840 /* get current video input */ 841 if (v4l2_ioctl(s->fd, VIDIOC_G_INPUT, &s->channel) < 0) { 842 res = AVERROR(errno); 843 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_INPUT): %s\n", av_err2str(res)); 844 return res; 845 } 846 } 847 848 /* enum input */ 849 input.index = s->channel; 850 if (v4l2_ioctl(s->fd, VIDIOC_ENUMINPUT, &input) < 0) { 851 res = AVERROR(errno); 852 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_ENUMINPUT): %s\n", av_err2str(res)); 853 return res; 854 } 855 s->std_id = input.std; 856 av_log(s1, AV_LOG_DEBUG, "Current input_channel: %d, input_name: %s, input_std: %"PRIx64"\n", 857 s->channel, input.name, (uint64_t)input.std); 858 859 if (s->list_format) { 860 list_formats(s1, s->fd, s->list_format); 861 return AVERROR_EXIT; 862 } 863 864 if (s->list_standard) { 865 list_standards(s1); 866 return AVERROR_EXIT; 867 } 868 869 avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */ 870 871 if ((res = v4l2_set_parameters(s1)) < 0) 872 return res; 873 874 if (s->pixel_format) { 875 AVCodec *codec = avcodec_find_decoder_by_name(s->pixel_format); 876 877 if (codec) 878 s1->video_codec_id = codec->id; 879 880 pix_fmt = av_get_pix_fmt(s->pixel_format); 881 882 if (pix_fmt == AV_PIX_FMT_NONE && !codec) { 883 av_log(s1, AV_LOG_ERROR, "No such input format: %s.\n", 884 s->pixel_format); 885 886 return AVERROR(EINVAL); 887 } 888 } 889 890 if (!s->width && !s->height) { 891 struct v4l2_format fmt = { .type = V4L2_BUF_TYPE_VIDEO_CAPTURE }; 892 893 av_log(s1, AV_LOG_VERBOSE, 894 "Querying the device for the current frame size\n"); 895 if (v4l2_ioctl(s->fd, VIDIOC_G_FMT, &fmt) < 0) { 896 res = AVERROR(errno); 897 av_log(s1, AV_LOG_ERROR, "ioctl(VIDIOC_G_FMT): %s\n", av_err2str(res)); 898 return res; 899 } 900 901 s->width = fmt.fmt.pix.width; 902 s->height = fmt.fmt.pix.height; 903 av_log(s1, AV_LOG_VERBOSE, 904 "Setting frame size to %dx%d\n", s->width, s->height); 905 } 906 907 res = device_try_init(s1, pix_fmt, &s->width, &s->height, &desired_format, &codec_id); 908 if (res < 0) { 909 v4l2_close(s->fd); 910 return res; 911 } 912 913 /* If no pixel_format was specified, the codec_id was not known up 914 * until now. Set video_codec_id in the context, as codec_id will 915 * not be available outside this function 916 */ 917 if (codec_id != AV_CODEC_ID_NONE && s1->video_codec_id == AV_CODEC_ID_NONE) 918 s1->video_codec_id = codec_id; 919 920 if ((res = av_image_check_size(s->width, s->height, 0, s1)) < 0) 921 return res; 922 923 s->frame_format = desired_format; 924 925 st->codec->pix_fmt = avpriv_fmt_v4l2ff(desired_format, codec_id); 926 s->frame_size = 927 avpicture_get_size(st->codec->pix_fmt, s->width, s->height); 928 929 if ((res = mmap_init(s1)) || 930 (res = mmap_start(s1)) < 0) { 931 v4l2_close(s->fd); 932 return res; 933 } 934 935 s->top_field_first = first_field(s, s->fd); 936 937 st->codec->codec_type = AVMEDIA_TYPE_VIDEO; 938 st->codec->codec_id = codec_id; 939 if (codec_id == AV_CODEC_ID_RAWVIDEO) 940 st->codec->codec_tag = 941 avcodec_pix_fmt_to_codec_tag(st->codec->pix_fmt); 942 else if (codec_id == AV_CODEC_ID_H264) { 943 st->need_parsing = AVSTREAM_PARSE_HEADERS; 944 } 945 if (desired_format == V4L2_PIX_FMT_YVU420) 946 st->codec->codec_tag = MKTAG('Y', 'V', '1', '2'); 947 else if (desired_format == V4L2_PIX_FMT_YVU410) 948 st->codec->codec_tag = MKTAG('Y', 'V', 'U', '9'); 949 st->codec->width = s->width; 950 st->codec->height = s->height; 951 if (st->avg_frame_rate.den) 952 st->codec->bit_rate = s->frame_size * av_q2d(st->avg_frame_rate) * 8; 953 954 return 0; 955} 956 957static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt) 958{ 959 struct video_data *s = s1->priv_data; 960 AVFrame *frame = s1->streams[0]->codec->coded_frame; 961 int res; 962 963 av_init_packet(pkt); 964 if ((res = mmap_read_frame(s1, pkt)) < 0) { 965 return res; 966 } 967 968 if (frame && s->interlaced) { 969 frame->interlaced_frame = 1; 970 frame->top_field_first = s->top_field_first; 971 } 972 973 return pkt->size; 974} 975 976static int v4l2_read_close(AVFormatContext *s1) 977{ 978 struct video_data *s = s1->priv_data; 979 980 if (avpriv_atomic_int_get(&s->buffers_queued) != s->buffers) 981 av_log(s1, AV_LOG_WARNING, "Some buffers are still owned by the caller on " 982 "close.\n"); 983 984 mmap_close(s); 985 986 v4l2_close(s->fd); 987 return 0; 988} 989 990#define OFFSET(x) offsetof(struct video_data, x) 991#define DEC AV_OPT_FLAG_DECODING_PARAM 992 993static const AVOption options[] = { 994 { "standard", "set TV standard, used only by analog frame grabber", OFFSET(standard), AV_OPT_TYPE_STRING, {.str = NULL }, 0, 0, DEC }, 995 { "channel", "set TV channel, used only by frame grabber", OFFSET(channel), AV_OPT_TYPE_INT, {.i64 = -1 }, -1, INT_MAX, DEC }, 996 { "video_size", "set frame size", OFFSET(width), AV_OPT_TYPE_IMAGE_SIZE, {.str = NULL}, 0, 0, DEC }, 997 { "pixel_format", "set preferred pixel format", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC }, 998 { "input_format", "set preferred pixel format (for raw video) or codec name", OFFSET(pixel_format), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC }, 999 { "framerate", "set frame rate", OFFSET(framerate), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, DEC }, 1000 1001 { "list_formats", "list available formats and exit", OFFSET(list_format), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, INT_MAX, DEC, "list_formats" }, 1002 { "all", "show all available formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_ALLFORMATS }, 0, INT_MAX, DEC, "list_formats" }, 1003 { "raw", "show only non-compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_RAWFORMATS }, 0, INT_MAX, DEC, "list_formats" }, 1004 { "compressed", "show only compressed formats", OFFSET(list_format), AV_OPT_TYPE_CONST, {.i64 = V4L_COMPFORMATS }, 0, INT_MAX, DEC, "list_formats" }, 1005 1006 { "list_standards", "list supported standards and exit", OFFSET(list_standard), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 1, DEC, "list_standards" }, 1007 { "all", "show all supported standards", OFFSET(list_standard), AV_OPT_TYPE_CONST, {.i64 = 1 }, 0, 0, DEC, "list_standards" }, 1008 1009 { "timestamps", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" }, 1010 { "ts", "set type of timestamps for grabbed frames", OFFSET(ts_mode), AV_OPT_TYPE_INT, {.i64 = 0 }, 0, 2, DEC, "timestamps" }, 1011 { "default", "use timestamps from the kernel", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_DEFAULT }, 0, 2, DEC, "timestamps" }, 1012 { "abs", "use absolute timestamps (wall clock)", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_ABS }, 0, 2, DEC, "timestamps" }, 1013 { "mono2abs", "force conversion from monotonic to absolute timestamps", OFFSET(ts_mode), AV_OPT_TYPE_CONST, {.i64 = V4L_TS_MONO2ABS }, 0, 2, DEC, "timestamps" }, 1014 { "use_libv4l2", "use libv4l2 (v4l-utils) conversion functions", OFFSET(use_libv4l2), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, DEC }, 1015 { NULL }, 1016}; 1017 1018static const AVClass v4l2_class = { 1019 .class_name = "V4L2 indev", 1020 .item_name = av_default_item_name, 1021 .option = options, 1022 .version = LIBAVUTIL_VERSION_INT, 1023 .category = AV_CLASS_CATEGORY_DEVICE_VIDEO_INPUT, 1024}; 1025 1026AVInputFormat ff_v4l2_demuxer = { 1027 .name = "video4linux2,v4l2", 1028 .long_name = NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"), 1029 .priv_data_size = sizeof(struct video_data), 1030 .read_header = v4l2_read_header, 1031 .read_packet = v4l2_read_packet, 1032 .read_close = v4l2_read_close, 1033 .flags = AVFMT_NOFILE, 1034 .priv_class = &v4l2_class, 1035}; 1036