FFmpeg/libavdevice/v4l2.c
Michel Bardiaux 48f7e1aeee Clarify the error message when video width, height, or framerate are not
specified.
Patch by Michel Bardiaux (mbardiaux AT mediaxim DOT be)

Originally committed as revision 11551 to svn://svn.ffmpeg.org/ffmpeg/trunk
2008-01-17 16:27:26 +00:00

644 lines
17 KiB
C

/*
* Video4Linux2 grab interface
* Copyright (c) 2000,2001 Fabrice Bellard.
* Copyright (c) 2006 Luca Abeni.
*
* Part of this file is based on the V4L2 video capture example
* (http://v4l2spec.bytesex.org/v4l2spec/capture.c)
*
* Thanks to Michael Niedermayer for providing the mapping between
* V4L2_PIX_FMT_* and PIX_FMT_*
*
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "avformat.h"
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/time.h>
#include <asm/types.h>
#include <linux/videodev2.h>
#include <time.h>
static const int desired_video_buffers = 256;
enum io_method {
io_read,
io_mmap,
io_userptr
};
struct video_data {
int fd;
int frame_format; /* V4L2_PIX_FMT_* */
enum io_method io_method;
int width, height;
int frame_rate;
int frame_rate_base;
int frame_size;
int top_field_first;
int buffers;
void **buf_start;
unsigned int *buf_len;
};
struct buff_data {
int index;
int fd;
};
struct fmt_map {
enum PixelFormat ff_fmt;
int32_t v4l2_fmt;
};
static struct fmt_map fmt_conversion_table[] = {
{
.ff_fmt = PIX_FMT_YUV420P,
.v4l2_fmt = V4L2_PIX_FMT_YUV420,
},
{
.ff_fmt = PIX_FMT_YUV422P,
.v4l2_fmt = V4L2_PIX_FMT_YUV422P,
},
{
.ff_fmt = PIX_FMT_YUYV422,
.v4l2_fmt = V4L2_PIX_FMT_YUYV,
},
{
.ff_fmt = PIX_FMT_UYVY422,
.v4l2_fmt = V4L2_PIX_FMT_UYVY,
},
{
.ff_fmt = PIX_FMT_YUV411P,
.v4l2_fmt = V4L2_PIX_FMT_YUV411P,
},
{
.ff_fmt = PIX_FMT_YUV410P,
.v4l2_fmt = V4L2_PIX_FMT_YUV410,
},
{
.ff_fmt = PIX_FMT_BGR24,
.v4l2_fmt = V4L2_PIX_FMT_BGR24,
},
{
.ff_fmt = PIX_FMT_RGB24,
.v4l2_fmt = V4L2_PIX_FMT_RGB24,
},
/*
{
.ff_fmt = PIX_FMT_RGB32,
.v4l2_fmt = V4L2_PIX_FMT_BGR32,
},
*/
{
.ff_fmt = PIX_FMT_GRAY8,
.v4l2_fmt = V4L2_PIX_FMT_GREY,
},
};
static int device_open(AVFormatContext *ctx, uint32_t *capabilities)
{
struct v4l2_capability cap;
int fd;
int res;
int flags = O_RDWR;
if (ctx->flags & AVFMT_FLAG_NONBLOCK) {
flags |= O_NONBLOCK;
}
fd = open(ctx->filename, flags, 0);
if (fd < 0) {
av_log(ctx, AV_LOG_ERROR, "Cannot open video device %s : %s\n",
ctx->filename, strerror(errno));
return -1;
}
res = ioctl(fd, VIDIOC_QUERYCAP, &cap);
// ENOIOCTLCMD definition only availble on __KERNEL__
if (res < 0 && errno == 515)
{
av_log(ctx, AV_LOG_ERROR, "QUERYCAP not implemented, probably V4L device but not supporting V4L2\n");
close(fd);
return -1;
}
if (res < 0) {
av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYCAP): %s\n",
strerror(errno));
close(fd);
return -1;
}
if ((cap.capabilities & V4L2_CAP_VIDEO_CAPTURE) == 0) {
av_log(ctx, AV_LOG_ERROR, "Not a video capture device\n");
close(fd);
return -1;
}
*capabilities = cap.capabilities;
return fd;
}
static int device_init(AVFormatContext *ctx, int *width, int *height, int pix_fmt)
{
struct video_data *s = ctx->priv_data;
int fd = s->fd;
struct v4l2_format fmt;
int res;
memset(&fmt, 0, sizeof(struct v4l2_format));
fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
fmt.fmt.pix.width = *width;
fmt.fmt.pix.height = *height;
fmt.fmt.pix.pixelformat = pix_fmt;
fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
res = ioctl(fd, VIDIOC_S_FMT, &fmt);
if ((*width != fmt.fmt.pix.width) || (*height != fmt.fmt.pix.height)) {
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);
*width = fmt.fmt.pix.width;
*height = fmt.fmt.pix.height;
}
return res;
}
static int first_field(int fd)
{
int res;
v4l2_std_id std;
res = ioctl(fd, VIDIOC_G_STD, &std);
if (res < 0) {
return 0;
}
if (std & V4L2_STD_NTSC) {
return 0;
}
return 1;
}
static uint32_t fmt_ff2v4l(enum PixelFormat pix_fmt)
{
int i;
for (i = 0; i < sizeof(fmt_conversion_table) / sizeof(struct fmt_map); i++) {
if (fmt_conversion_table[i].ff_fmt == pix_fmt) {
return fmt_conversion_table[i].v4l2_fmt;
}
}
return 0;
}
static enum PixelFormat fmt_v4l2ff(uint32_t pix_fmt)
{
int i;
for (i = 0; i < sizeof(fmt_conversion_table) / sizeof(struct fmt_map); i++) {
if (fmt_conversion_table[i].v4l2_fmt == pix_fmt) {
return fmt_conversion_table[i].ff_fmt;
}
}
return -1;
}
static int mmap_init(AVFormatContext *ctx)
{
struct video_data *s = ctx->priv_data;
struct v4l2_requestbuffers req;
int i, res;
memset(&req, 0, sizeof(struct v4l2_requestbuffers));
req.count = desired_video_buffers;
req.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
req.memory = V4L2_MEMORY_MMAP;
res = ioctl (s->fd, VIDIOC_REQBUFS, &req);
if (res < 0) {
if (errno == EINVAL) {
av_log(ctx, AV_LOG_ERROR, "Device does not support mmap\n");
} else {
av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_REQBUFS)\n");
}
return -1;
}
if (req.count < 2) {
av_log(ctx, AV_LOG_ERROR, "Insufficient buffer memory\n");
return -1;
}
s->buffers = req.count;
s->buf_start = av_malloc(sizeof(void *) * s->buffers);
if (s->buf_start == NULL) {
av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer pointers\n");
return -1;
}
s->buf_len = av_malloc(sizeof(unsigned int) * s->buffers);
if (s->buf_len == NULL) {
av_log(ctx, AV_LOG_ERROR, "Cannot allocate buffer sizes\n");
av_free(s->buf_start);
return -1;
}
for (i = 0; i < req.count; i++) {
struct v4l2_buffer buf;
memset(&buf, 0, sizeof(struct v4l2_buffer));
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
buf.index = i;
res = ioctl (s->fd, VIDIOC_QUERYBUF, &buf);
if (res < 0) {
av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QUERYBUF)\n");
return -1;
}
s->buf_len[i] = buf.length;
if (s->buf_len[i] < s->frame_size) {
av_log(ctx, AV_LOG_ERROR, "Buffer len [%d] = %d != %d\n", i, s->buf_len[i], s->frame_size);
return -1;
}
s->buf_start[i] = mmap (NULL, buf.length,
PROT_READ | PROT_WRITE, MAP_SHARED, s->fd, buf.m.offset);
if (s->buf_start[i] == MAP_FAILED) {
av_log(ctx, AV_LOG_ERROR, "mmap: %s\n", strerror(errno));
return -1;
}
}
return 0;
}
static int read_init(AVFormatContext *ctx)
{
return -1;
}
static void mmap_release_buffer(AVPacket *pkt)
{
struct v4l2_buffer buf;
int res, fd;
struct buff_data *buf_descriptor = pkt->priv;
memset(&buf, 0, sizeof(struct v4l2_buffer));
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
buf.index = buf_descriptor->index;
fd = buf_descriptor->fd;
av_free(buf_descriptor);
res = ioctl (fd, VIDIOC_QBUF, &buf);
if (res < 0) {
av_log(NULL, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF)\n");
}
pkt->data = NULL;
pkt->size = 0;
}
static int mmap_read_frame(AVFormatContext *ctx, AVPacket *pkt)
{
struct video_data *s = ctx->priv_data;
struct v4l2_buffer buf;
struct buff_data *buf_descriptor;
int res;
memset(&buf, 0, sizeof(struct v4l2_buffer));
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
/* FIXME: Some special treatment might be needed in case of loss of signal... */
while ((res = ioctl(s->fd, VIDIOC_DQBUF, &buf)) < 0 && (errno == EINTR));
if (res < 0) {
if (errno == EAGAIN) {
pkt->size = 0;
return AVERROR(EAGAIN);
}
av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_DQBUF): %s\n", strerror(errno));
return -1;
}
assert (buf.index < s->buffers);
if (buf.bytesused != s->frame_size) {
av_log(ctx, AV_LOG_ERROR, "The v4l2 frame is %d bytes, but %d bytes are expected\n", buf.bytesused, s->frame_size);
return -1;
}
/* Image is at s->buff_start[buf.index] */
pkt->data= s->buf_start[buf.index];
pkt->size = buf.bytesused;
pkt->pts = buf.timestamp.tv_sec * INT64_C(1000000) + buf.timestamp.tv_usec;
pkt->destruct = mmap_release_buffer;
buf_descriptor = av_malloc(sizeof(struct buff_data));
if (buf_descriptor == NULL) {
/* Something went wrong... Since av_malloc() failed, we cannot even
* allocate a buffer for memcopying into it
*/
av_log(ctx, AV_LOG_ERROR, "Failed to allocate a buffer descriptor\n");
res = ioctl (s->fd, VIDIOC_QBUF, &buf);
return -1;
}
buf_descriptor->fd = s->fd;
buf_descriptor->index = buf.index;
pkt->priv = buf_descriptor;
return s->buf_len[buf.index];
}
static int read_frame(AVFormatContext *ctx, AVPacket *pkt)
{
return -1;
}
static int mmap_start(AVFormatContext *ctx)
{
struct video_data *s = ctx->priv_data;
enum v4l2_buf_type type;
int i, res;
for (i = 0; i < s->buffers; i++) {
struct v4l2_buffer buf;
memset(&buf, 0, sizeof(struct v4l2_buffer));
buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
buf.memory = V4L2_MEMORY_MMAP;
buf.index = i;
res = ioctl (s->fd, VIDIOC_QBUF, &buf);
if (res < 0) {
av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_QBUF): %s\n", strerror(errno));
return -1;
}
}
type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
res = ioctl (s->fd, VIDIOC_STREAMON, &type);
if (res < 0) {
av_log(ctx, AV_LOG_ERROR, "ioctl(VIDIOC_STREAMON): %s\n", strerror(errno));
return -1;
}
return 0;
}
static void mmap_close(struct video_data *s)
{
enum v4l2_buf_type type;
int i;
type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
/* We do not check for the result, because we could
* not do anything about it anyway...
*/
ioctl(s->fd, VIDIOC_STREAMOFF, &type);
for (i = 0; i < s->buffers; i++) {
munmap(s->buf_start[i], s->buf_len[i]);
}
av_free(s->buf_start);
av_free(s->buf_len);
}
static int v4l2_set_parameters( AVFormatContext *s1, AVFormatParameters *ap )
{
struct video_data *s = s1->priv_data;
struct v4l2_input input;
struct v4l2_standard standard;
int i;
if(ap->channel>=0) {
/* set tv video input */
memset (&input, 0, sizeof (input));
input.index = ap->channel;
if(ioctl (s->fd, VIDIOC_ENUMINPUT, &input) < 0) {
av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl enum input failed:\n");
return AVERROR(EIO);
}
av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set input_id: %d, input: %s\n",
ap->channel, input.name);
if(ioctl (s->fd, VIDIOC_S_INPUT, &input.index) < 0 ) {
av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set input(%d) failed\n",
ap->channel);
return AVERROR(EIO);
}
}
if(ap->standard) {
av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s\n",
ap->standard );
/* set tv standard */
memset (&standard, 0, sizeof (standard));
for(i=0;;i++) {
standard.index = i;
if (ioctl(s->fd, VIDIOC_ENUMSTD, &standard) < 0) {
av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
ap->standard);
return AVERROR(EIO);
}
if(!strcasecmp(standard.name, ap->standard)) {
break;
}
}
av_log(s1, AV_LOG_DEBUG, "The V4L2 driver set standard: %s, id: %"PRIu64"\n",
ap->standard, standard.id);
if (ioctl(s->fd, VIDIOC_S_STD, &standard.id) < 0) {
av_log(s1, AV_LOG_ERROR, "The V4L2 driver ioctl set standard(%s) failed\n",
ap->standard);
return AVERROR(EIO);
}
}
return 0;
}
static int v4l2_read_header(AVFormatContext *s1, AVFormatParameters *ap)
{
struct video_data *s = s1->priv_data;
AVStream *st;
int width, height;
int res, frame_rate, frame_rate_base;
uint32_t desired_format, capabilities;
if (ap->width <= 0 || ap->height <= 0 || ap->time_base.den <= 0) {
av_log(s1, AV_LOG_ERROR, "Missing/Wrong width, height or framerate\n");
return -1;
}
width = ap->width;
height = ap->height;
frame_rate = ap->time_base.den;
frame_rate_base = ap->time_base.num;
if((unsigned)width > 32767 || (unsigned)height > 32767) {
av_log(s1, AV_LOG_ERROR, "Wrong size %dx%d\n", width, height);
return -1;
}
st = av_new_stream(s1, 0);
if (!st) {
return AVERROR(ENOMEM);
}
av_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
s->width = width;
s->height = height;
s->frame_rate = frame_rate;
s->frame_rate_base = frame_rate_base;
capabilities = 0;
s->fd = device_open(s1, &capabilities);
if (s->fd < 0) {
av_free(st);
return AVERROR(EIO);
}
av_log(s1, AV_LOG_INFO, "[%d]Capabilities: %x\n", s->fd, capabilities);
desired_format = fmt_ff2v4l(ap->pix_fmt);
if (desired_format == 0 || (device_init(s1, &width, &height, desired_format) < 0)) {
int i, done;
done = 0; i = 0;
while (!done) {
desired_format = fmt_conversion_table[i].v4l2_fmt;
if (device_init(s1, &width, &height, desired_format) < 0) {
desired_format = 0;
i++;
} else {
done = 1;
}
if (i == sizeof(fmt_conversion_table) / sizeof(struct fmt_map)) {
done = 1;
}
}
}
if (desired_format == 0) {
av_log(s1, AV_LOG_ERROR, "Cannot find a proper format.\n");
close(s->fd);
av_free(st);
return AVERROR(EIO);
}
s->frame_format = desired_format;
if( v4l2_set_parameters( s1, ap ) < 0 )
return AVERROR(EIO);
st->codec->pix_fmt = fmt_v4l2ff(desired_format);
s->frame_size = avpicture_get_size(st->codec->pix_fmt, width, height);
if (capabilities & V4L2_CAP_STREAMING) {
s->io_method = io_mmap;
res = mmap_init(s1);
if (res == 0) {
res = mmap_start(s1);
}
} else {
s->io_method = io_read;
res = read_init(s1);
}
if (res < 0) {
close(s->fd);
av_free(st);
return AVERROR(EIO);
}
s->top_field_first = first_field(s->fd);
st->codec->codec_type = CODEC_TYPE_VIDEO;
st->codec->codec_id = CODEC_ID_RAWVIDEO;
st->codec->width = width;
st->codec->height = height;
st->codec->time_base.den = frame_rate;
st->codec->time_base.num = frame_rate_base;
st->codec->bit_rate = s->frame_size * 1/av_q2d(st->codec->time_base) * 8;
return 0;
}
static int v4l2_read_packet(AVFormatContext *s1, AVPacket *pkt)
{
struct video_data *s = s1->priv_data;
int res;
if (s->io_method == io_mmap) {
av_init_packet(pkt);
res = mmap_read_frame(s1, pkt);
} else if (s->io_method == io_read) {
if (av_new_packet(pkt, s->frame_size) < 0)
return AVERROR(EIO);
res = read_frame(s1, pkt);
} else {
return AVERROR(EIO);
}
if (res < 0) {
return res;
}
if (s1->streams[0]->codec->coded_frame) {
s1->streams[0]->codec->coded_frame->interlaced_frame = 1;
s1->streams[0]->codec->coded_frame->top_field_first = s->top_field_first;
}
return s->frame_size;
}
static int v4l2_read_close(AVFormatContext *s1)
{
struct video_data *s = s1->priv_data;
if (s->io_method == io_mmap) {
mmap_close(s);
}
close(s->fd);
return 0;
}
AVInputFormat v4l2_demuxer = {
"video4linux2",
"video grab",
sizeof(struct video_data),
NULL,
v4l2_read_header,
v4l2_read_packet,
v4l2_read_close,
.flags = AVFMT_NOFILE,
};