video4linux2 input support
[libav.git] / libavformat / v4l2.c
1 /*
2 * Video4Linux2 grab interface
3 * Copyright (c) 2000,2001 Fabrice Bellard.
4 * Copyright (c) 2006 Luca Abeni.
5 *
6 * Part of this file is based on the V4L2 video capture example
7 * (http://v4l2spec.bytesex.org/v4l2spec/capture.c)
8 *
9 * Thanks to Michael Niedermayer for providing the mapping between
10 * V4L2_PIX_FMT_* and PIX_FMT_*
11 *
12 *
13 * This library is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU Lesser General Public
15 * License as published by the Free Software Foundation; either
16 * version 2 of the License, or (at your option) any later version.
17 *
18 * This library is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * Lesser General Public License for more details.
22 *
23 * You should have received a copy of the GNU Lesser General Public
24 * License along with this library; if not, write to the Free Software
25 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
26 */
27 #include "avformat.h"
28 #include <unistd.h>
29 #include <fcntl.h>
30 #include <sys/ioctl.h>
31 #include <sys/mman.h>
32 #include <sys/time.h>
33 #define _LINUX_TIME_H 1
34 #include <linux/videodev.h>
35 #include <time.h>
36
37 static const int desired_video_buffers = 256;
38
39 enum io_method {
40 io_read,
41 io_mmap,
42 io_userptr
43 };
44
45 struct video_data {
46 int fd;
47 int frame_format; /* V4L2_PIX_FMT_* */
48 enum io_method io_method;
49 int width, height;
50 int frame_rate;
51 int frame_rate_base;
52 int frame_size;
53 int top_field_first;
54
55 int buffers;
56 void **buf_start;
57 unsigned int *buf_len;
58 };
59
60 struct fmt_map {
61 enum PixelFormat ff_fmt;
62 int32_t v4l2_fmt;
63 };
64
65 static struct fmt_map fmt_conversion_table[] = {
66 {
67 .ff_fmt = PIX_FMT_YUV420P,
68 .v4l2_fmt = V4L2_PIX_FMT_YUV420,
69 },
70 {
71 .ff_fmt = PIX_FMT_YUV422P,
72 .v4l2_fmt = V4L2_PIX_FMT_YUV422P,
73 },
74 {
75 .ff_fmt = PIX_FMT_YUV422,
76 .v4l2_fmt = V4L2_PIX_FMT_YUYV,
77 },
78 {
79 .ff_fmt = PIX_FMT_UYVY422,
80 .v4l2_fmt = V4L2_PIX_FMT_UYVY,
81 },
82 {
83 .ff_fmt = PIX_FMT_YUV411P,
84 .v4l2_fmt = V4L2_PIX_FMT_YUV411P,
85 },
86 {
87 .ff_fmt = PIX_FMT_YUV410P,
88 .v4l2_fmt = V4L2_PIX_FMT_YUV410,
89 },
90 {
91 .ff_fmt = PIX_FMT_BGR24,
92 .v4l2_fmt = V4L2_PIX_FMT_BGR24,
93 },
94 {
95 .ff_fmt = PIX_FMT_RGB24,
96 .v4l2_fmt = V4L2_PIX_FMT_RGB24,
97 },
98 /*
99 {
100 .ff_fmt = PIX_FMT_RGBA32,
101 .v4l2_fmt = V4L2_PIX_FMT_BGR32,
102 },
103 */
104 {
105 .ff_fmt = PIX_FMT_GRAY8,
106 .v4l2_fmt = V4L2_PIX_FMT_GREY,
107 },
108 };
109
110 static int device_open(const char *devname, uint32_t *capabilities)
111 {
112 struct v4l2_capability cap;
113 int fd;
114 int res;
115
116 fd = open(devname, O_RDWR /*| O_NONBLOCK*/, 0);
117 if (fd < 0) {
118 av_log(NULL, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
119 devname, strerror(errno));
120
121 return -1;
122 }
123
124 res = ioctl(fd, VIDIOC_QUERYCAP, &cap);
125 if (res < 0) {
126 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
127 strerror(errno));
128
129 return -1;
130 }
131 if ((cap.capabilities & V4L2_CAP_VIDEO_CAPTURE) == 0) {
132 av_log(NULL, AV_LOG_ERROR, "Not a video capture device\n");
133
134 return -1;
135 }
136 *capabilities = cap.capabilities;
137
138 return fd;
139 }
140
141 static int device_init(int fd, int width, int height, int pix_fmt)
142 {
143 struct v4l2_format fmt;
144
145 memset(&fmt, 0, sizeof(struct v4l2_format));
146 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
147 fmt.fmt.pix.width = width;
148 fmt.fmt.pix.height = height;
149 fmt.fmt.pix.pixelformat = pix_fmt;
150 fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
151 return ioctl (fd, VIDIOC_S_FMT, &fmt);
152 }
153
154 static int first_field(int fd)
155 {
156 int res;
157 v4l2_std_id std;
158
159 res = ioctl(fd, VIDIOC_G_STD, &std);
160 if (res < 0) {
161 return 0;
162 }
163 if (std & V4L2_STD_NTSC) {
164 return 0;
165 }
166
167 return 1;
168 }
169
170 static uint32_t fmt_ff2v4l(enum PixelFormat pix_fmt)
171 {
172 int i;
173
174 for (i = 0; i < sizeof(fmt_conversion_table) / sizeof(struct fmt_map); i++) {
175 if (fmt_conversion_table[i].ff_fmt == pix_fmt) {
176 return fmt_conversion_table[i].v4l2_fmt;
177 }
178 }
179
180 return 0;
181 }
182
183 static enum PixelFormat fmt_v4l2ff(uint32_t pix_fmt)
184 {
185 int i;
186
187 for (i = 0; i < sizeof(fmt_conversion_table) / sizeof(struct fmt_map); i++) {
188 if (fmt_conversion_table[i].v4l2_fmt == pix_fmt) {
189 return fmt_conversion_table[i].ff_fmt;
190 }
191 }
192
193 return -1;
194 }
195
196 static int mmap_init(struct video_data *s)
197 {
198 struct v4l2_requestbuffers req;
199 int i, res;
200
201 memset(&req, 0, sizeof(struct v4l2_requestbuffers));
202 req.count = desired_video_buffers;
203 req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
204 req.memory = V4L2_MEMORY_MMAP;
205 res = ioctl (s->fd, VIDIOC_REQBUFS, &req);
206 if (res < 0) {
207 if (errno == EINVAL) {
208 av_log(NULL, AV_LOG_ERROR, "Device does not support mmap\n");
209 } else {
210 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
211 }
212
213 return -1;
214 }
215
216 if (req.count < 2) {
217 av_log(NULL, AV_LOG_ERROR, "Insufficient buffer memory\n");
218
219 return -1;
220 }
221 s->buffers = req.count;
222 s->buf_start = av_malloc(sizeof(void *) * s->buffers);
223 if (s->buf_start == NULL) {
224 av_log(NULL, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
225
226 return -1;
227 }
228 s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
229 if (s->buf_len == NULL) {
230 av_log(NULL, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
231 av_free(s->buf_start);
232
233 return -1;
234 }
235
236 for (i = 0; i < req.count; i++) {
237 struct v4l2_buffer buf;
238
239 memset(&buf, 0, sizeof(struct v4l2_buffer));
240 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
241 buf.memory = V4L2_MEMORY_MMAP;
242 buf.index = i;
243 res = ioctl (s->fd, VIDIOC_QUERYBUF, &buf);
244 if (res < 0) {
245 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
246
247 return -1;
248 }
249
250 s->buf_len[i] = buf.length;
251 if (s->buf_len[i] < s->frame_size) {
252 av_log(NULL, AV_LOG_ERROR, "Buffer len [%d] = %d != %d\n", i, s->buf_len[i], s->frame_size);
253
254 return -1;
255 }
256 s->buf_start[i] = mmap (NULL, buf.length,
257 PROT_READ | PROT_WRITE, MAP_SHARED, s->fd, buf.m.offset);
258 if (s->buf_start[i] == MAP_FAILED) {
259 av_log(NULL, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
260
261 return -1;
262 }
263 }
264
265 return 0;
266 }
267
268 static int read_init(struct video_data *s)
269 {
270 return -1;
271 }
272
273 static int mmap_read_frame(struct video_data *s, void *frame, int64_t *ts)
274 {
275 struct v4l2_buffer buf;
276 int res;
277
278 memset(&buf, 0, sizeof(struct v4l2_buffer));
279 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
280 buf.memory = V4L2_MEMORY_MMAP;
281
282 /* FIXME: Some special treatment might be needed in case of loss of signal... */
283 while ((res = ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 &&
284 ((errno == EAGAIN) || (errno == EINTR)));
285 if (res < 0) {
286 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n", strerror(errno));
287
288 return -1;
289 }
290 assert (buf.index < s->buffers);
291 assert(buf.bytesused == s->frame_size);
292 /* Image is at s->buff_start[buf.index] */
293 memcpy(frame, s->buf_start[buf.index], buf.bytesused);
294 *ts = buf.timestamp.tv_sec * int64_t_C(1000000) + buf.timestamp.tv_usec;
295
296 res = ioctl (s->fd, VIDIOC_QBUF, &buf);
297 if (res < 0) {
298 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF)\n");
299
300 return -1;
301 }
302
303 return s->buf_len[buf.index];
304 }
305
306 static int read_frame(struct video_data *s, void *frame, int64_t *ts)
307 {
308 return -1;
309 }
310
311 static int mmap_start(struct video_data *s)
312 {
313 enum v4l2_buf_type type;
314 int i, res;
315
316 for (i = 0; i < s->buffers; i++) {
317 struct v4l2_buffer buf;
318
319 memset(&buf, 0, sizeof(struct v4l2_buffer));
320 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
321 buf.memory = V4L2_MEMORY_MMAP;
322 buf.index = i;
323
324 res = ioctl (s->fd, VIDIOC_QBUF, &buf);
325 if (res < 0) {
326 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno));
327
328 return -1;
329 }
330 }
331
332 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
333 res = ioctl (s->fd, VIDIOC_STREAMON, &type);
334 if (res < 0) {
335 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n", strerror(errno));
336
337 return -1;
338 }
339
340 return 0;
341 }
342
343 static void mmap_close(struct video_data *s)
344 {
345 enum v4l2_buf_type type;
346 int i;
347
348 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
349 /* We do not check for the result, because we could
350 * not do anything about it anyway...
351 */
352 ioctl(s->fd, VIDIOC_STREAMOFF, &type);
353 for (i = 0; i < s->buffers; i++) {
354 munmap(s->buf_start[i], s->buf_len[i]);
355 }
356 av_free(s->buf_start);
357 av_free(s->buf_len);
358 }
359
360 static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
361 {
362 struct video_data *s = s1->priv_data;
363 AVStream *st;
364 int width, height;
365 int res, frame_rate, frame_rate_base;
366 uint32_t desired_format, capabilities;
367 const char *video_device;
368
369 if (!ap || ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
370 av_log(s1, AV_LOG_ERROR, "Missing/Wrong parameters\n");
371
372 return -1;
373 }
374
375 width = ap->width;
376 height = ap->height;
377 frame_rate = ap->time_base.den;
378 frame_rate_base = ap->time_base.num;
379
380 if((unsigned)width > 32767 || (unsigned)height > 32767) {
381 av_log(s1, AV_LOG_ERROR, "Wrong size %dx%d\n", width, height);
382
383 return -1;
384 }
385
386 st = av_new_stream(s1, 0);
387 if (!st) {
388 return -ENOMEM;
389 }
390 av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
391
392 s->width = width;
393 s->height = height;
394 s->frame_rate = frame_rate;
395 s->frame_rate_base = frame_rate_base;
396
397 video_device = ap->device;
398 if (!video_device) {
399 video_device = "/dev/video";
400 }
401 capabilities = 0;
402 s->fd = device_open(video_device, &capabilities);
403 if (s->fd < 0) {
404 av_free(st);
405
406 return AVERROR_IO;
407 }
408 av_log(s1, AV_LOG_ERROR, "[%d]Capabilities: %x\n", s->fd, capabilities);
409
410 desired_format = fmt_ff2v4l(ap->pix_fmt);
411 if (desired_format == 0 || (device_init(s->fd, width, height, desired_format) < 0)) {
412 int i, done;
413
414 done = 0; i = 0;
415 while (!done) {
416 desired_format = fmt_conversion_table[i].v4l2_fmt;
417 if (device_init(s->fd, width, height, desired_format) < 0) {
418 desired_format = 0;
419 i++;
420 } else {
421 done = 1;
422 }
423 if (i == sizeof(fmt_conversion_table) / sizeof(struct fmt_map)) {
424 done = 1;
425 }
426 }
427 }
428 if (desired_format == 0) {
429 av_log(s1, AV_LOG_ERROR, "Cannot find a proper format.\n");
430 close(s->fd);
431 av_free(st);
432
433 return AVERROR_IO;
434 }
435 s->frame_format = desired_format;
436
437 st->codec->pix_fmt = fmt_v4l2ff(desired_format);
438 s->frame_size = avpicture_get_size(st->codec->pix_fmt, width, height);
439 if (capabilities & V4L2_CAP_STREAMING) {
440 s->io_method = io_mmap;
441 res = mmap_init(s);
442 res = mmap_start(s);
443 } else {
444 s->io_method = io_read;
445 res = read_init(s);
446 }
447 if (res < 0) {
448 close(s->fd);
449 av_free(st);
450
451 return AVERROR_IO;
452 }
453 s->top_field_first = first_field(s->fd);
454
455 st->codec->codec_type = CODEC_TYPE_VIDEO;
456 st->codec->codec_id = CODEC_ID_RAWVIDEO;
457 st->codec->width = width;
458 st->codec->height = height;
459 st->codec->time_base.den = frame_rate;
460 st->codec->time_base.num = frame_rate_base;
461 st->codec->bit_rate = s->frame_size * 1/av_q2d(st->codec->time_base) * 8;
462
463 return 0;
464 }
465
466 static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
467 {
468 struct video_data *s = s1->priv_data;
469 int res;
470
471 if (av_new_packet(pkt, s->frame_size) < 0)
472 return AVERROR_IO;
473
474 if (s->io_method == io_mmap) {
475 res = mmap_read_frame(s, pkt->data, &pkt->pts);
476 } else if (s->io_method == io_read) {
477 res = read_frame(s, pkt->data, &pkt->pts);
478 } else {
479 return AVERROR_IO;
480 }
481 if (res < 0) {
482 return AVERROR_IO;
483 }
484
485 if (s1->streams[0]->codec->coded_frame) {
486 s1->streams[0]->codec->coded_frame->interlaced_frame = 1;
487 s1->streams[0]->codec->coded_frame->top_field_first = s->top_field_first;
488 }
489
490 return s->frame_size;
491 }
492
493 static int v4l2_read_close(AVFormatContext *s1)
494 {
495 struct video_data *s = s1->priv_data;
496
497 if (s->io_method == io_mmap) {
498 mmap_close(s);
499 }
500
501 close(s->fd);
502 return 0;
503 }
504
505 static AVInputFormat v4l2_format = {
506 "video4linux2",
507 "video grab",
508 sizeof(struct video_data),
509 NULL,
510 v4l2_read_header,
511 v4l2_read_packet,
512 v4l2_read_close,
513 .flags = AVFMT_NOFILE,
514 };
515
516 int v4l2_init(void)
517 {
518 av_register_input_format(&v4l2_format);
519 return 0;
520 }