2 * Video4Linux2 grab interface
3 * Copyright (c) 2000,2001 Fabrice Bellard
4 * Copyright (c) 2006 Luca Abeni
6 * Part of this file is based on the V4L2 video capture example
7 * (http://v4l2spec.bytesex.org/v4l2spec/capture.c)
9 * Thanks to Michael Niedermayer for providing the mapping between
10 * V4L2_PIX_FMT_* and PIX_FMT_*
13 * This file is part of FFmpeg.
15 * FFmpeg is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU Lesser General Public
17 * License as published by the Free Software Foundation; either
18 * version 2.1 of the License, or (at your option) any later version.
20 * FFmpeg is distributed in the hope that it will be useful,
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.
25 * You should have received a copy of the GNU Lesser General Public
26 * License along with FFmpeg; if not, write to the Free Software
27 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
30 #undef __STRICT_ANSI__ //workaround due to broken kernel headers
32 #include "libavformat/avformat.h"
35 #include <sys/ioctl.h>
38 #if HAVE_SYS_VIDEOIO_H
39 #include <sys/videoio.h>
41 #include <asm/types.h>
42 #include <linux/videodev2.h>
47 static const int desired_video_buffers
= 256;
57 int frame_format
; /* V4L2_PIX_FMT_* */
58 enum io_method io_method
;
65 unsigned int *buf_len
;
74 enum PixelFormat ff_fmt
;
78 static struct fmt_map fmt_conversion_table
[] = {
80 .ff_fmt
= PIX_FMT_YUV420P
,
81 .v4l2_fmt
= V4L2_PIX_FMT_YUV420
,
84 .ff_fmt
= PIX_FMT_YUV422P
,
85 .v4l2_fmt
= V4L2_PIX_FMT_YUV422P
,
88 .ff_fmt
= PIX_FMT_YUYV422
,
89 .v4l2_fmt
= V4L2_PIX_FMT_YUYV
,
92 .ff_fmt
= PIX_FMT_UYVY422
,
93 .v4l2_fmt
= V4L2_PIX_FMT_UYVY
,
96 .ff_fmt
= PIX_FMT_YUV411P
,
97 .v4l2_fmt
= V4L2_PIX_FMT_YUV411P
,
100 .ff_fmt
= PIX_FMT_YUV410P
,
101 .v4l2_fmt
= V4L2_PIX_FMT_YUV410
,
104 .ff_fmt
= PIX_FMT_RGB555
,
105 .v4l2_fmt
= V4L2_PIX_FMT_RGB555
,
108 .ff_fmt
= PIX_FMT_RGB565
,
109 .v4l2_fmt
= V4L2_PIX_FMT_RGB565
,
112 .ff_fmt
= PIX_FMT_BGR24
,
113 .v4l2_fmt
= V4L2_PIX_FMT_BGR24
,
116 .ff_fmt
= PIX_FMT_RGB24
,
117 .v4l2_fmt
= V4L2_PIX_FMT_RGB24
,
120 .ff_fmt
= PIX_FMT_BGRA
,
121 .v4l2_fmt
= V4L2_PIX_FMT_BGR32
,
124 .ff_fmt
= PIX_FMT_GRAY8
,
125 .v4l2_fmt
= V4L2_PIX_FMT_GREY
,
129 static int device_open(AVFormatContext
*ctx
, uint32_t *capabilities
)
131 struct v4l2_capability cap
;
136 if (ctx
->flags
& AVFMT_FLAG_NONBLOCK
) {
139 fd
= open(ctx
->filename
, flags
, 0);
141 av_log(ctx
, AV_LOG_ERROR
, "Cannot open video device %s : %s\n",
142 ctx
->filename
, strerror(errno
));
147 res
= ioctl(fd
, VIDIOC_QUERYCAP
, &cap
);
148 // ENOIOCTLCMD definition only availble on __KERNEL__
149 if (res
< 0 && errno
== 515)
151 av_log(ctx
, AV_LOG_ERROR
, "QUERYCAP not implemented, probably V4L device but not supporting V4L2\n");
157 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_QUERYCAP): %s\n",
163 if ((cap
.capabilities
& V4L2_CAP_VIDEO_CAPTURE
) == 0) {
164 av_log(ctx
, AV_LOG_ERROR
, "Not a video capture device\n");
169 *capabilities
= cap
.capabilities
;
174 static int device_init(AVFormatContext
*ctx
, int *width
, int *height
, int pix_fmt
)
176 struct video_data
*s
= ctx
->priv_data
;
178 struct v4l2_format fmt
;
181 memset(&fmt
, 0, sizeof(struct v4l2_format
));
182 fmt
.type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
183 fmt
.fmt
.pix
.width
= *width
;
184 fmt
.fmt
.pix
.height
= *height
;
185 fmt
.fmt
.pix
.pixelformat
= pix_fmt
;
186 fmt
.fmt
.pix
.field
= V4L2_FIELD_INTERLACED
;
187 res
= ioctl(fd
, VIDIOC_S_FMT
, &fmt
);
188 if ((*width
!= fmt
.fmt
.pix
.width
) || (*height
!= fmt
.fmt
.pix
.height
)) {
189 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
);
190 *width
= fmt
.fmt
.pix
.width
;
191 *height
= fmt
.fmt
.pix
.height
;
194 if (pix_fmt
!= fmt
.fmt
.pix
.pixelformat
) {
195 av_log(ctx
, AV_LOG_DEBUG
, "The V4L2 driver changed the pixel format from 0x%08X to 0x%08X\n", pix_fmt
, fmt
.fmt
.pix
.pixelformat
);
202 static int first_field(int fd
)
207 res
= ioctl(fd
, VIDIOC_G_STD
, &std
);
211 if (std
& V4L2_STD_NTSC
) {
218 static uint32_t fmt_ff2v4l(enum PixelFormat pix_fmt
)
222 for (i
= 0; i
< FF_ARRAY_ELEMS(fmt_conversion_table
); i
++) {
223 if (fmt_conversion_table
[i
].ff_fmt
== pix_fmt
) {
224 return fmt_conversion_table
[i
].v4l2_fmt
;
231 static enum PixelFormat
fmt_v4l2ff(uint32_t pix_fmt
)
235 for (i
= 0; i
< FF_ARRAY_ELEMS(fmt_conversion_table
); i
++) {
236 if (fmt_conversion_table
[i
].v4l2_fmt
== pix_fmt
) {
237 return fmt_conversion_table
[i
].ff_fmt
;
244 static int mmap_init(AVFormatContext
*ctx
)
246 struct video_data
*s
= ctx
->priv_data
;
247 struct v4l2_requestbuffers req
;
250 memset(&req
, 0, sizeof(struct v4l2_requestbuffers
));
251 req
.count
= desired_video_buffers
;
252 req
.type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
253 req
.memory
= V4L2_MEMORY_MMAP
;
254 res
= ioctl (s
->fd
, VIDIOC_REQBUFS
, &req
);
256 if (errno
== EINVAL
) {
257 av_log(ctx
, AV_LOG_ERROR
, "Device does not support mmap\n");
259 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_REQBUFS)\n");
266 av_log(ctx
, AV_LOG_ERROR
, "Insufficient buffer memory\n");
270 s
->buffers
= req
.count
;
271 s
->buf_start
= av_malloc(sizeof(void *) * s
->buffers
);
272 if (s
->buf_start
== NULL
) {
273 av_log(ctx
, AV_LOG_ERROR
, "Cannot allocate buffer pointers\n");
277 s
->buf_len
= av_malloc(sizeof(unsigned int) * s
->buffers
);
278 if (s
->buf_len
== NULL
) {
279 av_log(ctx
, AV_LOG_ERROR
, "Cannot allocate buffer sizes\n");
280 av_free(s
->buf_start
);
285 for (i
= 0; i
< req
.count
; i
++) {
286 struct v4l2_buffer buf
;
288 memset(&buf
, 0, sizeof(struct v4l2_buffer
));
289 buf
.type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
290 buf
.memory
= V4L2_MEMORY_MMAP
;
292 res
= ioctl (s
->fd
, VIDIOC_QUERYBUF
, &buf
);
294 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_QUERYBUF)\n");
299 s
->buf_len
[i
] = buf
.length
;
300 if (s
->buf_len
[i
] < s
->frame_size
) {
301 av_log(ctx
, AV_LOG_ERROR
, "Buffer len [%d] = %d != %d\n", i
, s
->buf_len
[i
], s
->frame_size
);
305 s
->buf_start
[i
] = mmap (NULL
, buf
.length
,
306 PROT_READ
| PROT_WRITE
, MAP_SHARED
, s
->fd
, buf
.m
.offset
);
307 if (s
->buf_start
[i
] == MAP_FAILED
) {
308 av_log(ctx
, AV_LOG_ERROR
, "mmap: %s\n", strerror(errno
));
317 static int read_init(AVFormatContext
*ctx
)
322 static void mmap_release_buffer(AVPacket
*pkt
)
324 struct v4l2_buffer buf
;
326 struct buff_data
*buf_descriptor
= pkt
->priv
;
328 if (pkt
->data
== NULL
) {
332 memset(&buf
, 0, sizeof(struct v4l2_buffer
));
333 buf
.type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
334 buf
.memory
= V4L2_MEMORY_MMAP
;
335 buf
.index
= buf_descriptor
->index
;
336 fd
= buf_descriptor
->fd
;
337 av_free(buf_descriptor
);
339 res
= ioctl (fd
, VIDIOC_QBUF
, &buf
);
341 av_log(NULL
, AV_LOG_ERROR
, "ioctl(VIDIOC_QBUF)\n");
347 static int mmap_read_frame(AVFormatContext
*ctx
, AVPacket
*pkt
)
349 struct video_data
*s
= ctx
->priv_data
;
350 struct v4l2_buffer buf
;
351 struct buff_data
*buf_descriptor
;
354 memset(&buf
, 0, sizeof(struct v4l2_buffer
));
355 buf
.type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
356 buf
.memory
= V4L2_MEMORY_MMAP
;
358 /* FIXME: Some special treatment might be needed in case of loss of signal... */
359 while ((res
= ioctl(s
->fd
, VIDIOC_DQBUF
, &buf
)) < 0 && (errno
== EINTR
));
361 if (errno
== EAGAIN
) {
364 return AVERROR(EAGAIN
);
366 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_DQBUF): %s\n", strerror(errno
));
370 assert (buf
.index
< s
->buffers
);
371 if (buf
.bytesused
!= s
->frame_size
) {
372 av_log(ctx
, AV_LOG_ERROR
, "The v4l2 frame is %d bytes, but %d bytes are expected\n", buf
.bytesused
, s
->frame_size
);
377 /* Image is at s->buff_start[buf.index] */
378 pkt
->data
= s
->buf_start
[buf
.index
];
379 pkt
->size
= buf
.bytesused
;
380 pkt
->pts
= buf
.timestamp
.tv_sec
* INT64_C(1000000) + buf
.timestamp
.tv_usec
;
381 pkt
->destruct
= mmap_release_buffer
;
382 buf_descriptor
= av_malloc(sizeof(struct buff_data
));
383 if (buf_descriptor
== NULL
) {
384 /* Something went wrong... Since av_malloc() failed, we cannot even
385 * allocate a buffer for memcopying into it
387 av_log(ctx
, AV_LOG_ERROR
, "Failed to allocate a buffer descriptor\n");
388 res
= ioctl (s
->fd
, VIDIOC_QBUF
, &buf
);
392 buf_descriptor
->fd
= s
->fd
;
393 buf_descriptor
->index
= buf
.index
;
394 pkt
->priv
= buf_descriptor
;
396 return s
->buf_len
[buf
.index
];
399 static int read_frame(AVFormatContext
*ctx
, AVPacket
*pkt
)
404 static int mmap_start(AVFormatContext
*ctx
)
406 struct video_data
*s
= ctx
->priv_data
;
407 enum v4l2_buf_type type
;
410 for (i
= 0; i
< s
->buffers
; i
++) {
411 struct v4l2_buffer buf
;
413 memset(&buf
, 0, sizeof(struct v4l2_buffer
));
414 buf
.type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
415 buf
.memory
= V4L2_MEMORY_MMAP
;
418 res
= ioctl (s
->fd
, VIDIOC_QBUF
, &buf
);
420 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno
));
426 type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
427 res
= ioctl (s
->fd
, VIDIOC_STREAMON
, &type
);
429 av_log(ctx
, AV_LOG_ERROR
, "ioctl(VIDIOC_STREAMON): %s\n", strerror(errno
));
437 static void mmap_close(struct video_data
*s
)
439 enum v4l2_buf_type type
;
442 type
= V4L2_BUF_TYPE_VIDEO_CAPTURE
;
443 /* We do not check for the result, because we could
444 * not do anything about it anyway...
446 ioctl(s
->fd
, VIDIOC_STREAMOFF
, &type
);
447 for (i
= 0; i
< s
->buffers
; i
++) {
448 munmap(s
->buf_start
[i
], s
->buf_len
[i
]);
450 av_free(s
->buf_start
);
454 static int v4l2_set_parameters( AVFormatContext
*s1
, AVFormatParameters
*ap
)
456 struct video_data
*s
= s1
->priv_data
;
457 struct v4l2_input input
;
458 struct v4l2_standard standard
;
462 /* set tv video input */
463 memset (&input
, 0, sizeof (input
));
464 input
.index
= ap
->channel
;
465 if(ioctl (s
->fd
, VIDIOC_ENUMINPUT
, &input
) < 0) {
466 av_log(s1
, AV_LOG_ERROR
, "The V4L2 driver ioctl enum input failed:\n");
470 av_log(s1
, AV_LOG_DEBUG
, "The V4L2 driver set input_id: %d, input: %s\n",
471 ap
->channel
, input
.name
);
472 if(ioctl (s
->fd
, VIDIOC_S_INPUT
, &input
.index
) < 0 ) {
473 av_log(s1
, AV_LOG_ERROR
, "The V4L2 driver ioctl set input(%d) failed\n",
480 av_log(s1
, AV_LOG_DEBUG
, "The V4L2 driver set standard: %s\n",
482 /* set tv standard */
483 memset (&standard
, 0, sizeof (standard
));
486 if (ioctl(s
->fd
, VIDIOC_ENUMSTD
, &standard
) < 0) {
487 av_log(s1
, AV_LOG_ERROR
, "The V4L2 driver ioctl set standard(%s) failed\n",
492 if(!strcasecmp(standard
.name
, ap
->standard
)) {
497 av_log(s1
, AV_LOG_DEBUG
, "The V4L2 driver set standard: %s, id: %"PRIu64
"\n",
498 ap
->standard
, (uint64_t)standard
.id
);
499 if (ioctl(s
->fd
, VIDIOC_S_STD
, &standard
.id
) < 0) {
500 av_log(s1
, AV_LOG_ERROR
, "The V4L2 driver ioctl set standard(%s) failed\n",
509 static int v4l2_read_header(AVFormatContext
*s1
, AVFormatParameters
*ap
)
511 struct video_data
*s
= s1
->priv_data
;
515 uint32_t desired_format
, capabilities
;
517 if (ap
->width
<= 0 || ap
->height
<= 0) {
518 av_log(s1
, AV_LOG_ERROR
, "Wrong size (%dx%d)\n", ap
->width
, ap
->height
);
525 if(avcodec_check_dimensions(s1
, ap
->width
, ap
->height
) < 0)
528 st
= av_new_stream(s1
, 0);
530 return AVERROR(ENOMEM
);
532 av_set_pts_info(st
, 64, 1, 1000000); /* 64 bits pts in us */
538 s
->fd
= device_open(s1
, &capabilities
);
542 av_log(s1
, AV_LOG_INFO
, "[%d]Capabilities: %x\n", s
->fd
, capabilities
);
544 desired_format
= fmt_ff2v4l(ap
->pix_fmt
);
545 if (desired_format
== 0 || (device_init(s1
, &width
, &height
, desired_format
) < 0)) {
550 desired_format
= fmt_conversion_table
[i
].v4l2_fmt
;
551 if (device_init(s1
, &width
, &height
, desired_format
) < 0) {
557 if (i
== FF_ARRAY_ELEMS(fmt_conversion_table
)) {
562 if (desired_format
== 0) {
563 av_log(s1
, AV_LOG_ERROR
, "Cannot find a proper format.\n");
568 s
->frame_format
= desired_format
;
570 if( v4l2_set_parameters( s1
, ap
) < 0 )
573 st
->codec
->pix_fmt
= fmt_v4l2ff(desired_format
);
574 s
->frame_size
= avpicture_get_size(st
->codec
->pix_fmt
, width
, height
);
575 if (capabilities
& V4L2_CAP_STREAMING
) {
576 s
->io_method
= io_mmap
;
579 res
= mmap_start(s1
);
582 s
->io_method
= io_read
;
590 s
->top_field_first
= first_field(s
->fd
);
592 st
->codec
->codec_type
= CODEC_TYPE_VIDEO
;
593 st
->codec
->codec_id
= CODEC_ID_RAWVIDEO
;
594 st
->codec
->width
= width
;
595 st
->codec
->height
= height
;
596 st
->codec
->time_base
.den
= ap
->time_base
.den
;
597 st
->codec
->time_base
.num
= ap
->time_base
.num
;
598 st
->codec
->bit_rate
= s
->frame_size
* 1/av_q2d(st
->codec
->time_base
) * 8;
603 static int v4l2_read_packet(AVFormatContext
*s1
, AVPacket
*pkt
)
605 struct video_data
*s
= s1
->priv_data
;
608 if (s
->io_method
== io_mmap
) {
610 res
= mmap_read_frame(s1
, pkt
);
611 } else if (s
->io_method
== io_read
) {
612 if (av_new_packet(pkt
, s
->frame_size
) < 0)
615 res
= read_frame(s1
, pkt
);
623 if (s1
->streams
[0]->codec
->coded_frame
) {
624 s1
->streams
[0]->codec
->coded_frame
->interlaced_frame
= 1;
625 s1
->streams
[0]->codec
->coded_frame
->top_field_first
= s
->top_field_first
;
628 return s
->frame_size
;
631 static int v4l2_read_close(AVFormatContext
*s1
)
633 struct video_data
*s
= s1
->priv_data
;
635 if (s
->io_method
== io_mmap
) {
643 AVInputFormat v4l2_demuxer
= {
645 NULL_IF_CONFIG_SMALL("Video4Linux2 device grab"),
646 sizeof(struct video_data
),
651 .flags
= AVFMT_NOFILE
,