those tables don't need to be extern
[libav.git] / libavformat / v4l2.c
CommitLineData
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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 *
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13 * This file is part of FFmpeg.
14 *
15 * FFmpeg is free software; you can redistribute it and/or
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16 * modify it under the terms of the GNU Lesser General Public
17 * License as published by the Free Software Foundation; either
b78e7197 18 * version 2.1 of the License, or (at your option) any later version.
0a7b514f 19 *
b78e7197 20 * FFmpeg is distributed in the hope that it will be useful,
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21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23 * Lesser General Public License for more details.
24 *
25 * You should have received a copy of the GNU Lesser General Public
b78e7197 26 * License along with FFmpeg; if not, write to the Free Software
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27 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
28 */
29#include "avformat.h"
30#include <unistd.h>
31#include <fcntl.h>
32#include <sys/ioctl.h>
33#include <sys/mman.h>
34#include <sys/time.h>
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35#include <asm/types.h>
36#include <linux/videodev2.h>
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37#include <time.h>
38
39static const int desired_video_buffers = 256;
40
41enum io_method {
42 io_read,
43 io_mmap,
44 io_userptr
45};
46
47struct video_data {
48 int fd;
49 int frame_format; /* V4L2_PIX_FMT_* */
50 enum io_method io_method;
51 int width, height;
52 int frame_rate;
53 int frame_rate_base;
54 int frame_size;
55 int top_field_first;
56
57 int buffers;
58 void **buf_start;
59 unsigned int *buf_len;
60};
61
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62struct buff_data {
63 int index;
64 int fd;
65};
66
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67struct fmt_map {
68 enum PixelFormat ff_fmt;
69 int32_t v4l2_fmt;
70};
71
72static struct fmt_map fmt_conversion_table[] = {
73 {
74 .ff_fmt = PIX_FMT_YUV420P,
75 .v4l2_fmt = V4L2_PIX_FMT_YUV420,
76 },
77 {
78 .ff_fmt = PIX_FMT_YUV422P,
79 .v4l2_fmt = V4L2_PIX_FMT_YUV422P,
80 },
81 {
71e445fc 82 .ff_fmt = PIX_FMT_YUYV422,
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83 .v4l2_fmt = V4L2_PIX_FMT_YUYV,
84 },
85 {
86 .ff_fmt = PIX_FMT_UYVY422,
87 .v4l2_fmt = V4L2_PIX_FMT_UYVY,
88 },
89 {
90 .ff_fmt = PIX_FMT_YUV411P,
91 .v4l2_fmt = V4L2_PIX_FMT_YUV411P,
92 },
93 {
94 .ff_fmt = PIX_FMT_YUV410P,
95 .v4l2_fmt = V4L2_PIX_FMT_YUV410,
96 },
97 {
98 .ff_fmt = PIX_FMT_BGR24,
99 .v4l2_fmt = V4L2_PIX_FMT_BGR24,
100 },
101 {
102 .ff_fmt = PIX_FMT_RGB24,
103 .v4l2_fmt = V4L2_PIX_FMT_RGB24,
104 },
105 /*
106 {
71e445fc 107 .ff_fmt = PIX_FMT_RGB32,
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108 .v4l2_fmt = V4L2_PIX_FMT_BGR32,
109 },
110 */
111 {
112 .ff_fmt = PIX_FMT_GRAY8,
113 .v4l2_fmt = V4L2_PIX_FMT_GREY,
114 },
115};
116
cc58300e 117static int device_open(AVFormatContext *ctx, uint32_t *capabilities)
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118{
119 struct v4l2_capability cap;
120 int fd;
121 int res;
122
cc58300e 123 fd = open(ctx->filename, O_RDWR /*| O_NONBLOCK*/, 0);
0a7b514f 124 if (fd < 0) {
c7238c72 125 av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
cc58300e 126 ctx->filename, strerror(errno));
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127
128 return -1;
129 }
130
131 res = ioctl(fd, VIDIOC_QUERYCAP, &cap);
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132 // ENOIOCTLCMD definition only availble on __KERNEL__
133 if (res < 0 && errno == 515)
134 {
c7238c72 135 av_log(ctx, AV_LOG_ERROR, "QUERYCAP not implemented, probably V4L device but not supporting V4L2\n");
2b63c222 136 close(fd);
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137
138 return -1;
139 }
0a7b514f 140 if (res < 0) {
c7238c72 141 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
0a7b514f 142 strerror(errno));
2b63c222 143 close(fd);
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144
145 return -1;
146 }
147 if ((cap.capabilities & V4L2_CAP_VIDEO_CAPTURE) == 0) {
c7238c72 148 av_log(ctx, AV_LOG_ERROR, "Not a video capture device\n");
2b63c222 149 close(fd);
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150
151 return -1;
152 }
153 *capabilities = cap.capabilities;
154
155 return fd;
156}
157
c7238c72 158static int device_init(AVFormatContext *ctx, int *width, int *height, int pix_fmt)
0a7b514f 159{
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160 struct video_data *s = ctx->priv_data;
161 int fd = s->fd;
0a7b514f 162 struct v4l2_format fmt;
24300af4 163 int res;
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164
165 memset(&fmt, 0, sizeof(struct v4l2_format));
166 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
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167 fmt.fmt.pix.width = *width;
168 fmt.fmt.pix.height = *height;
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169 fmt.fmt.pix.pixelformat = pix_fmt;
170 fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
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171 res = ioctl(fd, VIDIOC_S_FMT, &fmt);
172 if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
c7238c72 173 av_log(ctx, AV_LOG_INFO, "The V4L2 driver changed the video from %dx%d to %dx%d\n", *width, *height, fmt.fmt.pix.width, fmt.fmt.pix.height);
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174 *width = fmt.fmt.pix.width;
175 *height = fmt.fmt.pix.height;
176 }
177
178 return res;
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179}
180
181static int first_field(int fd)
182{
183 int res;
184 v4l2_std_id std;
185
186 res = ioctl(fd, VIDIOC_G_STD, &std);
187 if (res < 0) {
188 return 0;
189 }
190 if (std & V4L2_STD_NTSC) {
191 return 0;
192 }
193
194 return 1;
195}
196
197static uint32_t fmt_ff2v4l(enum PixelFormat pix_fmt)
198{
199 int i;
200
201 for (i = 0; i < sizeof(fmt_conversion_table) / sizeof(struct fmt_map); i++) {
202 if (fmt_conversion_table[i].ff_fmt == pix_fmt) {
203 return fmt_conversion_table[i].v4l2_fmt;
204 }
205 }
206
207 return 0;
208}
209
210static enum PixelFormat fmt_v4l2ff(uint32_t pix_fmt)
211{
212 int i;
213
214 for (i = 0; i < sizeof(fmt_conversion_table) / sizeof(struct fmt_map); i++) {
215 if (fmt_conversion_table[i].v4l2_fmt == pix_fmt) {
216 return fmt_conversion_table[i].ff_fmt;
217 }
218 }
219
220 return -1;
221}
222
c7238c72 223static int mmap_init(AVFormatContext *ctx)
0a7b514f 224{
c7238c72 225 struct video_data *s = ctx->priv_data;
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226 struct v4l2_requestbuffers req;
227 int i, res;
228
229 memset(&req, 0, sizeof(struct v4l2_requestbuffers));
230 req.count = desired_video_buffers;
231 req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
232 req.memory = V4L2_MEMORY_MMAP;
233 res = ioctl (s->fd, VIDIOC_REQBUFS, &req);
234 if (res < 0) {
235 if (errno == EINVAL) {
c7238c72 236 av_log(ctx, AV_LOG_ERROR, "Device does not support mmap\n");
0a7b514f 237 } else {
c7238c72 238 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
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239 }
240
241 return -1;
242 }
243
244 if (req.count < 2) {
c7238c72 245 av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
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246
247 return -1;
248 }
249 s->buffers = req.count;
250 s->buf_start = av_malloc(sizeof(void *) * s->buffers);
251 if (s->buf_start == NULL) {
c7238c72 252 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
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253
254 return -1;
255 }
256 s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
257 if (s->buf_len == NULL) {
c7238c72 258 av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
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259 av_free(s->buf_start);
260
261 return -1;
262 }
263
264 for (i = 0; i < req.count; i++) {
265 struct v4l2_buffer buf;
266
267 memset(&buf, 0, sizeof(struct v4l2_buffer));
268 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
269 buf.memory = V4L2_MEMORY_MMAP;
270 buf.index = i;
271 res = ioctl (s->fd, VIDIOC_QUERYBUF, &buf);
272 if (res < 0) {
c7238c72 273 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
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274
275 return -1;
276 }
277
278 s->buf_len[i] = buf.length;
279 if (s->buf_len[i] < s->frame_size) {
c7238c72 280 av_log(ctx, AV_LOG_ERROR, "Buffer len [%d] = %d != %d\n", i, s->buf_len[i], s->frame_size);
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281
282 return -1;
283 }
284 s->buf_start[i] = mmap (NULL, buf.length,
285 PROT_READ | PROT_WRITE, MAP_SHARED, s->fd, buf.m.offset);
286 if (s->buf_start[i] == MAP_FAILED) {
c7238c72 287 av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
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288
289 return -1;
290 }
291 }
292
293 return 0;
294}
295
c7238c72 296static int read_init(AVFormatContext *ctx)
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297{
298 return -1;
299}
300
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301static void mmap_release_buffer(AVPacket *pkt)
302{
303 struct v4l2_buffer buf;
304 int res, fd;
305 struct buff_data *buf_descriptor = pkt->priv;
306
307 memset(&buf, 0, sizeof(struct v4l2_buffer));
308 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
309 buf.memory = V4L2_MEMORY_MMAP;
310 buf.index = buf_descriptor->index;
311 fd = buf_descriptor->fd;
312 av_free(buf_descriptor);
313
314 res = ioctl (fd, VIDIOC_QBUF, &buf);
315 if (res < 0) {
316 av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF)\n");
317 }
318 pkt->data = NULL;
319 pkt->size = 0;
320}
321
322static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
0a7b514f 323{
c7238c72 324 struct video_data *s = ctx->priv_data;
0a7b514f 325 struct v4l2_buffer buf;
41536a60 326 struct buff_data *buf_descriptor;
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327 int res;
328
329 memset(&buf, 0, sizeof(struct v4l2_buffer));
330 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
331 buf.memory = V4L2_MEMORY_MMAP;
332
333 /* FIXME: Some special treatment might be needed in case of loss of signal... */
334 while ((res = ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 &&
335 ((errno == EAGAIN) || (errno == EINTR)));
336 if (res < 0) {
c7238c72 337 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n", strerror(errno));
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338
339 return -1;
340 }
341 assert (buf.index < s->buffers);
7c7e7464 342 if (buf.bytesused != s->frame_size) {
c7238c72 343 av_log(ctx, AV_LOG_ERROR, "The v4l2 frame is %d bytes, but %d bytes are expected\n", buf.bytesused, s->frame_size);
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344
345 return -1;
346 }
347
0a7b514f 348 /* Image is at s->buff_start[buf.index] */
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349 pkt->data= s->buf_start[buf.index];
350 pkt->size = buf.bytesused;
351 pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
352 pkt->destruct = mmap_release_buffer;
353 buf_descriptor = av_malloc(sizeof(struct buff_data));
354 if (buf_descriptor == NULL) {
355 /* Something went wrong... Since av_malloc() failed, we cannot even
356 * allocate a buffer for memcopying into it
357 */
358 av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
359 res = ioctl (s->fd, VIDIOC_QBUF, &buf);
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360
361 return -1;
362 }
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363 buf_descriptor->fd = s->fd;
364 buf_descriptor->index = buf.index;
365 pkt->priv = buf_descriptor;
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366
367 return s->buf_len[buf.index];
368}
369
41536a60 370static int read_frame(AVFormatContext *ctx, AVPacket *pkt)
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371{
372 return -1;
373}
374
c7238c72 375static int mmap_start(AVFormatContext *ctx)
0a7b514f 376{
c7238c72 377 struct video_data *s = ctx->priv_data;
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378 enum v4l2_buf_type type;
379 int i, res;
380
381 for (i = 0; i < s->buffers; i++) {
382 struct v4l2_buffer buf;
383
384 memset(&buf, 0, sizeof(struct v4l2_buffer));
385 buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
386 buf.memory = V4L2_MEMORY_MMAP;
387 buf.index = i;
388
389 res = ioctl (s->fd, VIDIOC_QBUF, &buf);
390 if (res < 0) {
c7238c72 391 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno));
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392
393 return -1;
394 }
395 }
396
397 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
398 res = ioctl (s->fd, VIDIOC_STREAMON, &type);
399 if (res < 0) {
c7238c72 400 av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n", strerror(errno));
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401
402 return -1;
403 }
404
405 return 0;
406}
407
408static void mmap_close(struct video_data *s)
409{
410 enum v4l2_buf_type type;
411 int i;
412
413 type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
414 /* We do not check for the result, because we could
415 * not do anything about it anyway...
416 */
417 ioctl(s->fd, VIDIOC_STREAMOFF, &type);
418 for (i = 0; i < s->buffers; i++) {
419 munmap(s->buf_start[i], s->buf_len[i]);
420 }
421 av_free(s->buf_start);
422 av_free(s->buf_len);
423}
424
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425static int v4l2_set_parameters( AVFormatContext *s1, AVFormatParameters *ap )
426{
427 struct video_data *s = s1->priv_data;
428 struct v4l2_input input;
429 struct v4l2_standard standard;
430 int i;
431
0d6c0732 432 if(ap->channel>=0) {
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433 /* set tv video input */
434 memset (&input, 0, sizeof (input));
435 input.index = ap->channel;
436 if(ioctl (s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
437 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl enum input failed:\n");
438 return AVERROR_IO;
439 }
440
441 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set input_id: %d, input: %s\n",
442 ap->channel, input.name);
443 if(ioctl (s->fd, VIDIOC_S_INPUT, &input.index) < 0 ) {
444 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set input(%d) failed\n",
445 ap->channel);
446 return AVERROR_IO;
447 }
0d6c0732 448 }
f5ad81f5 449
0d6c0732 450 if(ap->standard) {
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451 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s\n",
452 ap->standard );
453 /* set tv standard */
454 memset (&standard, 0, sizeof (standard));
455 for(i=0;;i++) {
456 standard.index = i;
457 if (ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
458 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
459 ap->standard);
460 return AVERROR_IO;
461 }
462
463 if(!strcasecmp(standard.name, ap->standard)) {
464 break;
465 }
466 }
467
468 av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s, id: %"PRIu64"\n",
469 ap->standard, standard.id);
470 if (ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
471 av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
472 ap->standard);
473 return AVERROR_IO;
474 }
0d6c0732 475 }
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476
477 return 0;
478}
479
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480static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
481{
482 struct video_data *s = s1->priv_data;
483 AVStream *st;
484 int width, height;
485 int res, frame_rate, frame_rate_base;
486 uint32_t desired_format, capabilities;
0a7b514f 487
c04c3282 488 if (ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
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489 av_log(s1, AV_LOG_ERROR, "Missing/Wrong parameters\n");
490
491 return -1;
492 }
493
494 width = ap->width;
495 height = ap->height;
496 frame_rate = ap->time_base.den;
497 frame_rate_base = ap->time_base.num;
498
499 if((unsigned)width > 32767 || (unsigned)height > 32767) {
500 av_log(s1, AV_LOG_ERROR, "Wrong size %dx%d\n", width, height);
501
502 return -1;
503 }
504
505 st = av_new_stream(s1, 0);
506 if (!st) {
8fa36ae0 507 return AVERROR(ENOMEM);
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508 }
509 av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
510
511 s->width = width;
512 s->height = height;
513 s->frame_rate = frame_rate;
514 s->frame_rate_base = frame_rate_base;
515
0a7b514f 516 capabilities = 0;
cc58300e 517 s->fd = device_open(s1, &capabilities);
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518 if (s->fd < 0) {
519 av_free(st);
520
521 return AVERROR_IO;
522 }
60023e32 523 av_log(s1, AV_LOG_INFO, "[%d]Capabilities: %x\n", s->fd, capabilities);
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524
525 desired_format = fmt_ff2v4l(ap->pix_fmt);
c7238c72 526 if (desired_format == 0 || (device_init(s1, &width, &height, desired_format) < 0)) {
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527 int i, done;
528
529 done = 0; i = 0;
530 while (!done) {
531 desired_format = fmt_conversion_table[i].v4l2_fmt;
c7238c72 532 if (device_init(s1, &width, &height, desired_format) < 0) {
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533 desired_format = 0;
534 i++;
535 } else {
536 done = 1;
537 }
538 if (i == sizeof(fmt_conversion_table) / sizeof(struct fmt_map)) {
539 done = 1;
540 }
541 }
542 }
543 if (desired_format == 0) {
544 av_log(s1, AV_LOG_ERROR, "Cannot find a proper format.\n");
545 close(s->fd);
546 av_free(st);
547
548 return AVERROR_IO;
549 }
550 s->frame_format = desired_format;
551
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552 if( v4l2_set_parameters( s1, ap ) < 0 )
553 return AVERROR_IO;
554
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555 st->codec->pix_fmt = fmt_v4l2ff(desired_format);
556 s->frame_size = avpicture_get_size(st->codec->pix_fmt, width, height);
557 if (capabilities & V4L2_CAP_STREAMING) {
558 s->io_method = io_mmap;
c7238c72 559 res = mmap_init(s1);
eaddc471 560 if (res == 0) {
c7238c72 561 res = mmap_start(s1);
eaddc471 562 }
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563 } else {
564 s->io_method = io_read;
c7238c72 565 res = read_init(s1);
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566 }
567 if (res < 0) {
568 close(s->fd);
569 av_free(st);
570
571 return AVERROR_IO;
572 }
573 s->top_field_first = first_field(s->fd);
574
575 st->codec->codec_type = CODEC_TYPE_VIDEO;
576 st->codec->codec_id = CODEC_ID_RAWVIDEO;
577 st->codec->width = width;
578 st->codec->height = height;
579 st->codec->time_base.den = frame_rate;
580 st->codec->time_base.num = frame_rate_base;
581 st->codec->bit_rate = s->frame_size * 1/av_q2d(st->codec->time_base) * 8;
582
583 return 0;
584}
585
586static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
587{
588 struct video_data *s = s1->priv_data;
589 int res;
590
0a7b514f 591 if (s->io_method == io_mmap) {
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592 av_init_packet(pkt);
593 res = mmap_read_frame(s1, pkt);
0a7b514f 594 } else if (s->io_method == io_read) {
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595 if (av_new_packet(pkt, s->frame_size) < 0)
596 return AVERROR_IO;
597
598 res = read_frame(s1, pkt);
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599 } else {
600 return AVERROR_IO;
601 }
602 if (res < 0) {
603 return AVERROR_IO;
604 }
605
606 if (s1->streams[0]->codec->coded_frame) {
607 s1->streams[0]->codec->coded_frame->interlaced_frame = 1;
608 s1->streams[0]->codec->coded_frame->top_field_first = s->top_field_first;
609 }
610
611 return s->frame_size;
612}
613
614static int v4l2_read_close(AVFormatContext *s1)
615{
616 struct video_data *s = s1->priv_data;
617
618 if (s->io_method == io_mmap) {
619 mmap_close(s);
620 }
621
622 close(s->fd);
623 return 0;
624}
625
ff70e601 626AVInputFormat v4l2_demuxer = {
0a7b514f
LA
627 "video4linux2",
628 "video grab",
629 sizeof(struct video_data),
630 NULL,
631 v4l2_read_header,
632 v4l2_read_packet,
633 v4l2_read_close,
634 .flags = AVFMT_NOFILE,
635};